15 results on '"Alves NC"'
Search Results
2. Action of swim-up and caffeine on equine frozen sperm.
- Author
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Alves NC, Diniz SA, Viegas RN, Arigoni AL, Freitas MM, Lana ÂQ, and Lagares MA
- Abstract
Cryopreservation of equine semen is crucial to semen commercialization. However, it reduces sperm motility and longevity. Thus, sperm selection methods and addition of motility-activating substances to sperm, such as caffeine, may improve sperm quality of equine frozen semen. The objective of the current work was to evaluate the effects of caffeine on recovery and quality parameters of frozen-thawed sperm subjected to swim-up selection to be used in intracytoplasmic sperm injection (ICSI) in assisted reproductive techniques. Stallion semen were frozen and after thawing different caffeine concentrations were added to the samples performing four treatments control (no caffeine), 3, 5, and 7.5 mM caffeine. Sperm kinematic and motility were assessed by computer-assisted sperm analysis (CASA). Then, the four treated samples were submitted to the swim-up sperm selection, and the number of recovered sperm and morphology were evaluated at four times 20, 40, 60, and 80 min. The swim-up increased the recovery proportion of normal morphology sperm without (80.1±1%) or with caffeine addition (3mM: 81.2±1%, 5mM: 79.9±1% and 7.5 mM 78.9±1%) compared to the thawed semen (70±2%). However, the addition of 5 mM caffeine induced an increase in sperm motility (38.9±2.8 vs. 32.6±3.4%, P<0.05), and sperm recovery after swim-up (7.9x10
6 vs. 3.4x106 sperm/ml, P<0.05) compared to the control. The addition of 5 mM caffeine to frozen-thawed equine semen before swim-up selection improved sperm motility and increased the sperm recovery rate while not decreasing the percentage of morphologically normal sperm. Thus, caffeine addition to frozen-thawed equine semen before swim-up selection has potential clinical application in improving sperm quality for use in ICSI., Competing Interests: Conflicts of interest: The authors have no conflict of interest to declare.- Published
- 2022
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3. L-carnitine added to post-thawed semen acts as an antioxidant and a stimulator of equine sperm metabolism.
- Author
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Lagares MA, da Silva GC, Cortes SF, Moreira FHM, Neves FCD, Alves NC, Viegas RN, Diniz TF, Lemos VS, de Rezende ASC, Freitas MM, Stahlberg R, and Nicolino RR
- Subjects
- Animals, Antioxidants pharmacology, Carnitine pharmacology, Cryopreservation veterinary, Female, Fertility, Horses, Insemination, Artificial veterinary, Male, Pregnancy, Sperm Motility, Spermatozoa, Semen, Semen Preservation veterinary
- Abstract
The objective of this study was to enhance the in vitro sperm quality and in vivo fertility of frozen-thawed equine semen by the addition of l-carnitine (LC) to post-thawed semen. Different concentrations of LC were added to thawed samples to obtain four treatments control and 0.5, 1 and 2 mM LC. In the in vitro experiments, sperm motility and kinematics, membrane integrity and intracellular calcium ion concentration ([Ca
2+ ]i ) were investigated, and the antioxidant bioactivity of LC was assessed by measuring hydrogen peroxide and nitrite concentrations (NO2 - ). The fertility rate was assessed via the artificial insemination of mares. The treatment with 1 mM LC increased sperm [Ca2+ ]i (60.6 ± 0.05 AU), reduced nitrite concentration (39.1 ± 14.9 µM/µg protein), increased the sperm straightness percentage (STR: 78.3 ± 5.3%) and increased the pregnancy rate (75%) as compared to the control ([Ca2+ ]i 48.4 ± 0.05 AU, NO2 - concentration 63.1 ± 14.4 µM/µg protein, STR 67.5 ± 7.9%, 12.5% pregnancy rate, p < 0.05). These results suggest that 1 mM LC acts as an antioxidant and stimulator of sperm metabolism in post-thawed equine semen, increasing the fertility rate. Thus, addition of LC might be an alternative to improve the fertility of poor quality post-thawed equine semen., (© 2021 Wiley-VCH GmbH.)- Published
- 2022
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4. Addition of caffeine to equine thawed sperm increases motility and decreases nitrite concentration.
- Author
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Alves NC, Diniz SA, Viegas RN, Cortes SF, Costa ED, Freitas MM, Martins-Filho OA, Araújo MSS, Lana ÂMQ, Wenceslau RR, and Lagares MA
- Subjects
- Animals, Caffeine pharmacology, Cryopreservation, Female, Horses, Humans, Insemination, Artificial veterinary, Male, Nitrites, Pregnancy, Spermatozoa, Semen Preservation veterinary, Sperm Motility
- Abstract
The aim of this study was to improve the quality of frozen-thawed equine sperm by the addition of caffeine to it. Semen from nine stallions was frozen and different concentrations of caffeine (3, 5 and 7.5 mM) were added to frozen-thawed semen. The sperm kinetic parameters, membrane functionality and integrity, and acrosome integrity and spontaneous acrosome reacted sperm were evaluated with a computer-assisted sperm analysis, a hypoosmotic swelling test and epifluorescent microscopy, respectively. Nitrite and hydroperoxide concentrations of frozen-thawed semen were measured using spectrophotometry. Sperm fertility was evaluated by artificial insemination (AI) of 16 mares with thawed ejaculates (control and 5 mM caffeine-treated groups). Compared to that in the control, the addition of 5 mM caffeine induced an increase in sperm motility (38.9 ± 2.8 versus 32.6 ± 3.4%), and a decrease in nitrite concentration (11.4 ± 2.1 versus 12.8 ± 2.9 µM/µg protein, p < .05). Moreover, the pregnancy rate from AI in the caffeine group was significantly higher (62.5%) than that in the control group (12.5%). These data suggest that caffeine reduced the nitrite concentration and enhanced sperm motility in thawed equine sperm, thus increasing the fertility rate in mares inseminated with caffeine-treated equine semen., (© 2020 Wiley-VCH GmbH.)
- Published
- 2021
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5. Does Coenzyme Q10 Exert Antioxidant Effect on Frozen Equine Sperm?
- Author
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de Albuquerque Lagares M, Silva GCD, Cortes SF, Luz SB, de Resende AC, Alves NC, Wenceslau RR, and Stahlberg R
- Subjects
- Animals, Freezing, Horses, Hydrogen Peroxide, Male, Sperm Motility, Spermatozoa, Ubiquinone analogs & derivatives, Antioxidants pharmacology, Semen Preservation veterinary
- Abstract
During semen cryopreservation, the sensitivity of equine sperm to oxidative stress is increased by the eliminated seminal plasma. Thus, antioxidant addition to the semen extender can be helpful to the sperm survival after freezing and thawing. This work aimed to test whether coenzyme Q10 (CoQ10) added in different concentrations to the INRA 82 freezing extender has antioxidant function on equine sperm to improve its fertilizing ability. Semen samples from five stallions were frozen with the extenders: (T1) INRA 82, control, (T2) T1+ 5 μM CoQ10, (T3) T1+ 25 μM CoQ10, and (T4) T1+ 50 μM CoQ10. After sample thawing, sperm motility and kinetics characteristics were evaluated using a computer-assisted sperm analysis and sperm membrane functionality and integrity were evaluated with a hypo-osmotic swelling test and an epifluorescence microscopy, respectively. The nitrite (NO
2 - ) and hydrogen peroxide (H2 O2 ) concentrations of the semen samples were measured with spectrophotometry. There was no difference on the sperm characteristics among all treatments (P > .05). However, the 25 μM CoQ10 (T3) decreased NO2 - concentration (6.7 ± 2.2 μM/μg protein) compared with the treatments T1, T2, and T4 (64.3 ± 3.7, 59.4 ± 5.3, 45.1 ± 8.6 μM/μg protein), respectively, as well H2 O2 concentration (1.8 ± 0.3 μM/μg protein) compared with the control (4.6 ± 0.4 μM/μg protein) and 5 μM CoQ10 treatments (4.8 ± 0.2 μM/μg protein, P < .05). In conclusion, 25 μM CoQ10 plays a significant role as antioxidant to the frozen equine sperm, decreasing NO2 - and H2 O2 concentrations. Thus, its addition to the INRA 82 freezing extender may be beneficial to the fertilizing ability of equine semen., (Copyright © 2020 Elsevier Inc. All rights reserved.)- Published
- 2020
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6. Influence of Temperature on the Cyclic Fatigue Resistance of Reciproc Blue Instruments.
- Author
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Vieira TM, Alves NC, de Andrade Silva S, de Almeida AC, Telles CT, and Albuquerque DS
- Subjects
- Equipment Design, Equipment Failure, Temperature, Dental Instruments, Root Canal Preparation
- Abstract
Aim: To evaluate the cyclic fatigue resistance of Reciproc blue (RB) 40/0.06 instruments tested at room temperature (20° ± 0.5°C) and at body temperature (37° ± 0.5°C) in a simulated stainless steel canal., Materials and Methods: Twenty-four new RB 40/0.06 instruments were randomly divided into two groups ( n = 12) according to the temperature used. Dynamic fatigue testing was performed using an artificial stainless steel canal with a 60° curvature angle and a 5-mm radius of curvature. The temperature was controlled throughout the experiment with an underwater thermometer and a thermostat. The data were analyzed descriptively using the IBM SPSS 23.0 program, considering p < 0.05., Results: The time to fracture of the RB instruments differed significantly between the two temperatures (1083.82 seconds at 20°C and 403.80 seconds at 37°C). No significant differences were found in fragment size., Conclusion: An increase in temperature reduces the cyclic fatigue resistance of RB 40/0.06 instruments. The results of the study suggest that an intracanal cooling system can be favorable to the fracture resistance of the tested instruments., Clinical Significance: A cooling system of the root canal system is important in endodontic as it favors the cyclic fatigue resistance of Ni-Ti instruments.
- Published
- 2020
7. The quality of life of family health professionals: a systematic review and meta-synthesis.
- Author
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Pennisi PRC, Alves NC, Michelin PS, Medeiros-Souza L, Herval ÁM, and Paranhos LR
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- Humans, Workload psychology, Workload standards, Workplace psychology, Workplace standards, Family Health trends, Health Personnel psychology, Quality of Life psychology
- Abstract
Objectives: to perform a systematic review and meta-synthesis of qualitative studies about the work-related quality of life of Family Health Strategy professionals., Methods: this systematic review was developed to answer the following PVO question: "Which factors (variables) are associated with the work-related quality of life (outcome) of Family Health Strategy professionals (population)?" The PubMed, Scopus, Embase, SciELO, Web of Science, LILACS, Science Direct, OpenThesis, OpenGrey, and OATD databases were selected. The meta-synthesis analyzed the main codes and secondary codes of all included studies., Results: the database search resulted in 1,744 reports; six were considered eligible for the meta-synthesis. Four factors were considered for the quality of work life: working conditions; work processes; interpersonal relationships; and personal aspects., Conclusions: although this study confirms the adequacy of aspects commonly related to the quality of work life, other factors are important in the case of FHS professionals, especially work context.
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- 2020
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8. Influence of Temperature on the Cyclic Fatigue of Nickel-Titanium Instruments with Different Heat Treatments on Severely Curved Canals.
- Author
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Cardoso RM, Carvalho Alves NC, de Menezes SEAC, Batista SM, Vieira TM, Elgarten Rocha GN, de Melo Monteiro GQ, and de Albuquerque DS
- Subjects
- Dental Instruments, Equipment Design, Fatigue, Hot Temperature, Humans, Root Canal Preparation, Temperature, Nickel, Titanium
- Abstract
Aim: This study aims to investigate the influence of temperatures of 20 °C and 37 °C on the resistance to cyclic fatigue of NiTi instruments with different heat treatments, as tested in severely curved simulated canals., Materials and Methods: Seventy-two instruments were distributed according to the temperature used (20 °C and 37 °C): XP-endo Shaper (30/0.01), ProDesign Logic (30/0.05), and iRaCe (30/0.04). The instruments were rotated freely until the occurrence of fracture inside an artificial severely curved stainless steel canal, which had a 90° angle of curvature and a curvature radius of 5 mm. Kolmogorov-Smirnov, Wilcoxon, ANOVA, and Kruskal-Wallis tests were performed. A p value of <0.05 was considered statistically significant., Results: XP-endo Shaper instruments presented higher NCF values and time to failure compared with ProDesign Logic and iRaCe instruments at 20 °C and 37 °C ( p < 0.001)., Conclusion: Within the limitations of this study, the results show that the body temperature (37 °C) significantly lowers the resistance to cyclic fatigue of all instruments compared with 20 °C., Clinical Significance: Body temperature is an important factor in the results of cyclic fatigue tests.
- Published
- 2019
9. hsa-miR-29c and hsa-miR-135b differential expression as potential biomarker of gastric carcinogenesis.
- Author
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Vidal AF, Cruz AM, Magalhães L, Pereira AL, Anaissi AK, Alves NC, Albuquerque PJ, Burbano RM, Demachki S, and Ribeiro-dos-Santos Â
- Subjects
- Adenocarcinoma microbiology, Adenocarcinoma pathology, Adenomatous Polyposis Coli Protein genetics, Area Under Curve, Carcinogenesis pathology, Case-Control Studies, DNA (Cytosine-5-)-Methyltransferases genetics, DNA Methyltransferase 3A, Epigenesis, Genetic, Gastric Mucosa chemistry, Gastric Mucosa pathology, Gastritis, Atrophic microbiology, Gastritis, Atrophic pathology, Gene Expression Profiling, Gene Expression Regulation, Neoplastic, Helicobacter pylori isolation & purification, Humans, Kruppel-Like Factor 4, Kruppel-Like Transcription Factors genetics, Metaplasia, Predictive Value of Tests, ROC Curve, Stomach Neoplasms microbiology, Stomach Neoplasms pathology, Adenocarcinoma genetics, Biomarkers, Tumor genetics, Carcinogenesis genetics, Gastritis, Atrophic genetics, MicroRNAs genetics, Stomach Neoplasms genetics
- Abstract
Aim: To investigate the expression profiles of hsa-miR-29c and hsa-miR-135b in gastric mucosal samples and their values as gastric carcinogenesis biomarkers., Methods: The expression levels of hsa-miR-29c and hsa-miR-135b in normal gastric mucosa, non-atrophic chronic gastritis, intestinal metaplasia and intestinal-type gastric adenocarcinoma were analysed using quantitative real-time PCR. The difference between hsa-miR-29c and hsa-miR-135b expression profiles in the grouped samples was evaluated by ANOVA and Student's t-test tests. The results were adjusted for multiple testing by using Bonferroni's correction. P values ≤ 0.05 were considered statistically significant. To evaluate hsa-miR-29c and hsa-miR-135b expressions as potential biomarkers of gastric carcinogenesis, we performed a receiver operating characteristic curve analysis and the derived area under the curve, and a Categorical Principal Components Analysis. In silico identification of the genetic targets of hsa-miR-29c and hsa-miR-135b was performed using different prediction tools, in order to identify possible genes involved in gastric carcinogenesis., Results: The expression levels of hsa-miR-29c were higher in normal gastric mucosal samples, and decreased progressively in non-atrophic chronic gastritis samples, intestinal metaplasia samples and intestinal-type gastric adenocarcinoma samples. The expression of hsa-miR-29c in the gastric lesions showed that non-atrophic gastritis have an intermediate profile to gastric normal mucosa and intestinal-type gastric adenocarcinoma, and that intestinal metaplasia samples presented an expression pattern similar to that in intestinal-type gastric adenocarcinoma. This microRNA (miRNA) has a good discriminatory accuracy between normal gastric samples and (1) intestinal-type gastric adenocarcinoma; and (2) intestinal metaplasia, and regulates the DMNT3A oncogene. hsa-miR-135b is up-regulated in non-atrophic chronic gastritis and intestinal metaplasia samples and down-regulated in normal gastric mucosa and intestinal-type gastric adenocarcinoma samples. Non-atrophic chronic gastritis and intestinal metaplasia are significantly different from normal gastric mucosa samples. hsa-miR-135b expression presented a greater discriminatory accuracy between normal samples and gastric lesions. This miRNA was associated with Helicobacter pylori presence in non-atrophic chronic gastritis samples and regulates the APC and KLF4 tumour suppressor genes., Conclusion: Our results provide evidence of epigenetic alterations in non-atrophic chronic gastritis and intestinal metaplasia and suggest that hsa-miR-29c and hsa-miR-135b are promising biomarkers of gastric carcinogenesis.
- Published
- 2016
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10. Nicotinic α5 subunits drive developmental changes in the activation and morphology of prefrontal cortex layer VI neurons.
- Author
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Bailey CD, Alves NC, Nashmi R, De Biasi M, and Lambe EK
- Subjects
- Animals, Male, Membrane Potentials genetics, Mice, Mice, Inbred C57BL, Mice, Knockout, Mice, Transgenic, Prefrontal Cortex cytology, Prefrontal Cortex physiology, Receptors, Nicotinic genetics, Membrane Potentials physiology, Neurons cytology, Prefrontal Cortex growth & development, Receptors, Nicotinic physiology
- Abstract
Background: Nicotinic signaling in prefrontal layer VI pyramidal neurons is important to the function of mature attention systems. The normal incorporation of α5 subunits into α4β2* nicotinic acetylcholine receptors augments nicotinic signaling in these neurons and is required for normal attention performance in adult mice. However, the role of α5 subunits in the development of the prefrontal cortex is not known., Methods: We sought to answer this question by examining nicotinic currents and neuronal morphology in layer VI neurons of medial prefrontal cortex of wild-type and α5 subunit knockout (α5(-/-)) mice during postnatal development and in adulthood., Results: In wild-type but not in α5(-/-) mice, there is a developmental peak in nicotinic acetylcholine currents in the third postnatal week. At this juvenile time period, the majority of neurons in all mice have long apical dendrites extending into cortical layer I. Yet, by early adulthood, wild-type but not α5(-/-) mice show a pronounced shift toward shorter apical dendrites. This cellular difference occurs in the absence of genotype differences in overall cortical morphology., Conclusions: Normal developmental changes in nicotinic signaling and dendritic morphology in prefrontal cortex depend on α5-comprising nicotinic acetylcholine receptors. It appears that these receptors mediate a specific developmental retraction of apical dendrites in layer VI neurons. This finding provides novel insight into the cellular mechanisms underlying the known attention deficits in α5(-/-) mice and potentially also into the pathophysiology of developmental neuropsychiatric disorders such as attention-deficit disorder and autism., (Copyright © 2012 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.)
- Published
- 2012
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11. [The nurse providing care to trauma victims in pain: the fifth vital sign].
- Author
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Ribeiro NC, Barreto SC, Hora EC, and de Sousa RM
- Subjects
- Adult, Female, Humans, Male, Pain etiology, Pain Measurement, Vital Signs, Wounds and Injuries complications, Pain nursing, Wounds and Injuries nursing
- Abstract
This qualitative study evaluated nurses' knowledge regarding pain in trauma victims. This study was developed at a public hospital, using a questionnaire and a knowledge test, both of which were treated using Content Analysis. The sample as comprised by 27 nurses, mainly women (92.6%), with an average age of 31±10.3 years and most with less than one year since their graduation (51.8%). Results evinced pain as an unpleasant sensation, a warning sign and a subjective experience. Pain measurement is seen from subjective and objective perspectives. Most nurses (59.3%) are not familiar with the evaluation instruments and, among those with some familiarity, the numerical scale was the most referred. The strategies for pain control mentioned by the nurses were measured as pharmacologic and non-pharmacologic and associated. All nurses considered that pain measurement is important and that is a pathway to a humanized and qualified treatment that guides the therapeutic conduct and reestablished the patients' well-being.
- Published
- 2011
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12. Developmental sex differences in nicotinic currents of prefrontal layer VI neurons in mice and rats.
- Author
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Alves NC, Bailey CD, Nashmi R, and Lambe EK
- Subjects
- Acetylcholine pharmacology, Animals, Carbachol pharmacology, Female, Immunohistochemistry, Luminescent Proteins genetics, Luminescent Proteins metabolism, Male, Membrane Potentials drug effects, Mice, Mice, Inbred C57BL, Microscopy, Fluorescence, Nicotinic Agonists pharmacology, Patch-Clamp Techniques, Prefrontal Cortex cytology, Rats, Rats, Sprague-Dawley, Receptors, Nicotinic genetics, Receptors, Nicotinic metabolism, Sex Factors, Species Specificity, Time Factors, Neurons physiology, Nicotine pharmacology, Prefrontal Cortex physiology, Receptors, Nicotinic physiology
- Abstract
Background: There is a large sex difference in the prevalence of attention deficit disorder; yet, relatively little is known about sex differences in the development of prefrontal attention circuitry. In male rats, nicotinic acetylcholine receptors excite corticothalamic neurons in layer VI, which are thought to play an important role in attention by gating the sensitivity of thalamic neurons to incoming stimuli. These nicotinic currents in male rats are significantly larger during the first postnatal month when prefrontal circuitry is maturing. The present study was undertaken to investigate whether there are sex differences in the nicotinic currents in prefrontal layer VI neurons during development., Methodology/principal Findings: Using whole cell recording in prefrontal brain slice, we examined the inward currents elicited by nicotinic stimulation in male and female rats and two strains of mice. We found a prominent sex difference in the currents during the first postnatal month when males had significantly greater nicotinic currents in layer VI neurons compared to females. These differences were apparent with three agonists: acetylcholine, carbachol, and nicotine. Furthermore, the developmental sex difference in nicotinic currents occurred despite male and female rodents displaying a similar pattern and proportion of layer VI neurons possessing a key nicotinic receptor subunit., Conclusions/significance: This is the first illustration at a cellular level that prefrontal attention circuitry is differently affected by nicotinic receptor stimulation in males and females during development. This transient sex difference may help to define the cellular and circuit mechanisms that underlie vulnerability to attention deficit disorder.
- Published
- 2010
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13. Assessing lay beliefs about generic medicines: Development of the generic medicines scale.
- Author
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Figueiras MJ, Alves NC, Marcelino D, Cortes MA, Weinman J, and Horne R
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Portugal, United States, Young Adult, Drugs, Generic, Health Knowledge, Attitudes, Practice, Surveys and Questionnaires
- Abstract
The aims of this study were to develop a scale to assess lay beliefs about generic medicines, and to investigate whether these beliefs differ according to demographic factors in an opportunistic general public sample. In the pilot study, the participants were 92 men and 136 women, and in the main study there were 314 men and 505 women. At both stages, the participants completed a questionnaire measuring beliefs about generic medicines, preference for medicines and demographic information. The scale has good face validity, showing a satisfactory level of internal consistency. An exploratory principal component analysis revealed a two-factor structure concerning beliefs about generic medicines, comprising two core themes (efficacy and similarity to brand medicines), in two different samples. Older participants showed a stronger belief in similarity with brand names than the younger group. Higher educated participants showed a stronger belief in the efficacy of generics. The opportunity to assess beliefs about generic medicines may have implications for adherence, for the implementation of health policies and for decision making about medicines.
- Published
- 2009
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14. Developmental excitation of corticothalamic neurons by nicotinic acetylcholine receptors.
- Author
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Kassam SM, Herman PM, Goodfellow NM, Alves NC, and Lambe EK
- Subjects
- Acetylcholine pharmacology, Age Factors, Analysis of Variance, Animals, Animals, Newborn, Cholinergic Agents pharmacology, Dose-Response Relationship, Drug, Electric Stimulation methods, Excitatory Amino Acid Antagonists pharmacology, Male, Membrane Potentials drug effects, Membrane Potentials physiology, Membrane Potentials radiation effects, Neural Pathways physiology, Neurons classification, Patch-Clamp Techniques methods, Rats, Rhodamines metabolism, Sodium Channel Blockers pharmacology, Statistics, Nonparametric, Tetrodotoxin pharmacology, Neurons physiology, Prefrontal Cortex cytology, Prefrontal Cortex growth & development, Receptors, Nicotinic physiology, Thalamus cytology, Thalamus growth & development
- Abstract
In this study, we show robust nicotinic excitation of pyramidal neurons in layer VI of prefrontal cortex. This layer contains the corticothalamic neurons, which gate thalamic activity and play a critical role in attention. Our experiments tested nicotinic excitation across postnatal development, using whole-cell recordings in prefrontal brain slices from rats. These experiments showed that layer VI neurons have peak nicotinic currents during the first postnatal month, a time period of intensive cortical development in rodents. We demonstrate that these currents are mediated directly by postsynaptic nicotinic receptors and can be suppressed by a competitive antagonist of alpha(4)beta(2)* nicotinic receptors. To record from identified corticothalamic neurons, we performed stereotaxic surgery to label the neurons projecting to medial dorsal thalamus. As hypothesized, recordings from these retrogradely labeled neurons in layer VI showed prominent nicotinic currents. Finally, we examined the effects of the drug nicotine on layer VI neurons and probed for the potential involvement of the accessory subunit, alpha(5), in their receptors. A level of nicotine similar to that found in the blood of smokers elicits a stable inward current in layer VI neurons, yet this exposure desensitizes approximately 50% of the subsequent current elicited by acetylcholine. An allosteric modulator of alpha(4)beta(2)alpha(5) receptors resulted in a 2.5-fold potentiation of submaximal nicotinic currents. This result is consistent with the expression of the relatively rare alpha(5) nicotinic subunit in layer VI. In summary, we show that layer VI corticothalamic neurons can be strongly excited during development by an unusual subtype of nicotinic receptor.
- Published
- 2008
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15. [Microbiological analysis of mineral water and drinking water of reservoir supplies, Brazil].
- Author
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Alves NC, Odorizzi AC, and Goulart FC
- Subjects
- Brazil, Fresh Water microbiology, Urban Health, Water Purification, Enterobacteriaceae isolation & purification, Mineral Waters microbiology, Water Microbiology, Water Supply standards
- Abstract
The aim of this study was to evaluate the microbiological quality of different commercial mineral water brands, wells and reservoir supplies in surrounding areas of the city of Marília, Brazil, to determine the amount of total and fecal coliforms. Eighteen samples of each source (mineral and reservoir supplies) were analyzed using Colilert Technique in cellophane. The results revealed that one sample of mineral water and one sample collected from the reservoir supply had been contaminated by a bacterium of the total coliform group, and there were found one bacterium/100 ml of water. None of the water samples showed contamination by fecal coliforms.
- Published
- 2002
- Full Text
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