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2.
Front Endocrinol (Lausanne) ; 13: 980505, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36187134

RESUMO

The COVID-19 pandemic has stimulated a rapid shift towards telemedicine, which has had tremendous repercussions on all domains of the healthcare ecosystem. The effects of the transition to telemedicine on post-graduate medical education and on patient care provided by trainees have not been fully elucidated. Focusing on the multifaceted scope of endocrinology teaching clinics, the experience garnered by endocrinology fellows, preceptors, and patients through the adoption of virtual visits has shed new light on relevant challenges that require specific attention. First, we identified a divergent trend in glycated hemoglobin in people with type 1 diabetes according to their use of continuous glucose monitoring (CGM). Second, the patient's perspective highlighted positive aspects, including expanded options for clinical care, but also limitations in communication with clinicians for people without access to videoconferencing tools or EHR-based portals. Finally, regarding medical training evaluation and skills-based learning, academic centers, professional organizations, and clinical educators should develop new teaching curricula suitable for a telemedicine-based environment. While simultaneously facing numerous pressures, fellows can potentially spearhead new models of care delivery and innovative approaches to clinical education leveraging telemedicine.


Assuntos
COVID-19 , Glicemia , Automonitorização da Glicemia , COVID-19/epidemiologia , Ecossistema , Educação de Pós-Graduação em Medicina , Hemoglobinas Glicadas , Humanos , Pandemias
3.
J Glob Health ; 12: 04044, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35788091

RESUMO

Background: Intensive Care Unit (ICU) patients are exposed to various medications, especially during infusion, and the amount of infusion drugs and the rate of their application may negatively affect their health status. A deep learning model can monitor a patient's continuous reaction to tranquillizer therapy, analyze the treatment plans of experts to avoid severe situations such as reverse medication associations, work with a convenient mediator, and change the treatment plans of specialists as needed. Methods: Generally, patients' treatment histories are linked together via a period grouping connection, which is usually burdened by missing information. Displaying time-succession via Repetitive Neural Organization (RNO) is the best available solution. However, it's possible that a patient's treatment may be prolonged, which RNN may not be able to demonstrate in this manner. Results: We propose the use of the LSTM-RNN driven by heterogeneous medicine events to predict the patient's outcome, as well as the Regular Language Handling and Gaussian Cycle, which can handle boisterous, deficient, inadequate, heterogeneous, and unevenly tested prescription records of patients while addressing the missing value issue using a piece-based Gaussian cycle. Conclusions: We emphasize the semantic relevance of every medication event and the grouping of drug events on patients in our study. We will focus specifically on LSTM-RNN and Phased LSTM-RNN for showing treatment results and information attribution using bit-based Gaussian cycles. We worked on Staged LSTM-RNN.


Assuntos
Big Data , Aprendizado Profundo , Humanos , Unidades de Terapia Intensiva , Redes Neurais de Computação , Medição de Risco
4.
Braz J Biol ; 84: e262662, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35830134

RESUMO

A socio-economic study was conducted in district Mardan of the Khyber Pakhtunkhwa (KP) province of Pakistan to get a comprehensive knowledge of the agroforestry tree species grown on the farmlands, their yield, and carbon stock. For yield and carbon stock estimation, data were collected from 59 sample plots by measuring the diameter, height, volume, and biomass of selected agroforestry tree species through D-tape and Haga altimeter. A total of 59 sample plots were inventoried using 2.5 percent sampling intensity. Each sample plot has an area of 0.5 ha, where each tree with a Diameter at Breast Height (DBH) ≥ 5 cm was inventoried. The calculated amount of volume of each tree species was then converted to biomass by multiplying it by the density of wood and the Biomass Expansion Factor (BEF). Total yield and C stock for the selected agroforestry tree species were 11535.2 metric tons and 2102.2 metric tons, respectively. Populus euroamericana is classified as the main tree with 28% growing stock prior to Morus alba by 21%, while Melia azedarach, Eucalyptus camaldulensis, Dalbergia sissoo, Acacia nilotica, Salix tetrasperma, and Bombax ceiba consist of 15%, 12%, 8%, 6%,7% and 3% growing stock respectively. Among the species found in different sampling plots the yield of Populus euroamericana was found to be 4747.5 metric tons and it was followed by the species Morus alba found at 2027.3 metric tons. Similarly, the volume for Melia azedarach, Eucalyptus camaldulensis, Dalbergia sissoo, Salix spp, Boombox ceiba, and Acacia nilotica was 1532.2 tons,1503 ton,745.7,203.5ton, 555.4ton and 220.5ton, respectively. The carbon stock for Populus euroamericana was calculated as 777.8 ton/ha, while for Eucalyptus camaldulensis, Melia azedarach, Morus alba, Dalbergia sissoo, Acacia nilotica, Salix species, and Bombax ceiba it was calculated as 312.3ton/ha, 272.1ton/ha, 363ton/ha, 245.1ton/ha, 51.4ton/ha, 27.3ton/ha and 53.2ton/ha, respectively. The questionnaire survey conducted for price dynamics showed that the majority of respondents purchase timber from the market for construction. But they use farm trees with low-quality city construction. They dislike using local timber in the conventional building as timber from farm trees is liable to insect attack. Rs. 50,000-100000, (33.33%) of daily sales was concluded from 50% of the trader while (16.7%) of the traders have their sales between Rs.150,000-200,000. Therefore, it is concluded by the authors that both provincial and federal government should promote agroforestry in Pakistan through different incentives because it has the potential to cope with dilemma of deforestation of natural forests and improve the livelihood of local peoples. It is strongly recommended that special projects just like the Ten Billion Tree Afforestation Project (T-BTTP) should be launched for agroforestry plantation and promotion in the country to sustain the ecological harmony and uplift the socio-economic condition of the peoples of Pakistan.


Assuntos
Eucalyptus , Árvores , Biomassa , Carbono/análise , Florestas , Paquistão
5.
Braz J Biol ; 84: e260615, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35544796

RESUMO

This article describes the environmental impacts of producing a single seedling in forest nurseries of selected districts (i.e., Haripur, Abbottabad, and Mansehra) of Hazara Division of Khyber Pakhtunkhwa, Pakistan using the life cycle assessment (LCA) approach. This study was based on the cradle-to-gate approach which begins with the pre-nursery stage and progresses toward the main nursery before transplanting seedlings into the plantation site. Data or life cycle inventory (LCI) of seedling production were collected through questionnaire surveys and personal meetings with forest nurseries managers and workers regarding consumption of different inputs such as electricity, diesel, fertilizers, herbicides, and polyethylene bags, organic manure, and water consumption. The SimaPro software version 8.5 and the CML2000 v2.05 environmental model was applied to perform life cycle impact assessment (LCIA) for a single seedling production in forest nurseries in the study area. In line with the objectives of the study, primary data regarding inputs and outputs of the nurseries were collected from 35 nurseries in the study area by using a random questionnaire method. In addition, secondary data were taken from online databases such as Eco-invent v.3.2 CORRIM and peer-reviewed published literature. For this study, a functional unit of a single seedling was considered. Production weighted average data were modeled in the latest environmental modeling software i.e., SimaPro v.8.5 for ten US-EPA most wanted environmental impacts, such as global warming potential (GWP), abiotic depletion (AD), eutrophication potential (EP), acidification potential (AP), freshwater aquatic eco-toxicity (FAE), marine water eco-toxicity (MWE), terrestrial eco-toxicity (TE), ozone layer depletion (OLD), photochemical oxidation (PO), and human toxicity (HT). The results showed that the highest environmental impact posed by a single seedling was marine aquatic eco-toxicity (11.31360 kg 1,4-DB eq), followed by global warming potential (0.02945 kg CO2 eq) and (0.01227 kg 1,4-DB eq) human toxicity. The primary reason for these environmental burdens was the use of synthetic fertilizers in forest nurseries and the consumption of fossil fuels in nursery mechanization and transportation activities. The total cumulative energy demand for a single seedling was (0.800 MJ) with more than 90% contribution from fossil fuel energy resources such as petrol and diesel. It is therefore highly recommended to use renewable energy resources and organic fertilizers instead of chemical fertilizers in forest nurseries to avoid and minimize greenhouse gas emissions (GHS) and other toxic emissions in the study area.


Assuntos
Fertilizantes , Plântula , Florestas , Combustíveis Fósseis , Humanos , Paquistão
6.
Braz J Biol ; 84: e260614, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35475996

RESUMO

Payment for ecosystem services (PES) is a mechanism where a consumer is able and ready to pay for the protection of the precise ecosystem service and there must be a provider such as local societies receiving an economic resource, who in return, must have the ability to maintain that ecosystem service. Economic valuation provides basis for payment for ecosystem services. Therefore, objective of this study was to evaluate tourism and carbon stock services of the Islamabad Capital Territory (ICT), Pakistan. Two forest zones (Chirpine and Scrub) of Islamabad capital territory (ICT) were selected for estimation of carbon stock and their carbon credits and carbon worth, a questionnaire-based survey was conducted for tourism as a payment for ecosystem services. The method for carbon stock assessment was systematic sampling for Chirpine forest whereas random sampling was done for scrub forest. The size of sampling plot was 17.84 m radius, and a total of 93 plots (49 Scrub zone and 44 Chirpine zone) was taken in the study area. The carbon stock of both zones (Chirpine and Scrub zone) is 22556.75 ton/ha (Chirpine 20105.79, Scrub 2450.96) and total carbon dioxide sequestered by both zone is 82557.72 ton/ha (Chirpine 73587.2, Scrub 8970.52), total carbon credits of both zone is 302160.87 (Chirpine 269328.97, Scrub 32831.9) and the carbon worth of both Chirpine and scrub zone is 4532418.92 $ (Chirpine 4039937.09$, Scrub 492481.83$). Similarly, from tourism point of view, in Shakar Parian, 94% tourists were agreed for PES whereas 6% were disagreed for the PES (the 6% tourist were disagreed to contribute for PES, 40% were agreed for Rs.5 contribution and 54% for Rs.10.). moreover, in Lake view Park, 97% tourists were agreed and 3% are disagreed (In Lake View Park 5% tourists were disagreed for the PES contribution whereas 32% were agreed for Rs.5 and 63% were for Rs.10). In Damen e Koh, around 87% tourist were agreed and 13% were disagreed, (24% were agreed for the contribution of Rs.5 and 63% tourists were agreed for the contribution of Rs.10). In Marghazar Zoo, 93% tourists were agreed (22% were agreed for contribution of Rs.5 and 71% tourist were agreed for contribution of Rs.10) and 7% are disagreed for PES whereas 7% tourists were not agreed for contribution. PES may implement to compensate forest and parks manager to ensure better management of the forests and parks. Due to prime location and scenic beauty of the ICT, it has huge potential for implementation of PES mechanism for sustainable forest management and conservation. Therefore, it is recommended that Capital Development Authority (CDA) Islamabad should devise a plan for implementation of PES in forests and parks of ICT for its sustainable management of recreational and forest resources.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Conservação dos Recursos Naturais/métodos , Florestas , Lagos , Paquistão
7.
Br J Dermatol ; 186(2): 227-235, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34319589

RESUMO

BACKGROUND: Previous studies have found conflicting results about the association of atopic dermatitis (AD) with hypertension. OBJECTIVES: To determine whether AD and AD severity are associated with hypertension. METHODS: A systematic review was performed of published studies in Ovid MEDLINE, Embase, Scopus, Web of Science, and GREAT (Global Resource for EczemA Trials) databases. At least two reviewers conducted title/abstract, full-text review and data extraction. Quality of evidence was assessed using the Newcastle-Ottawa Scale. RESULTS: Fifty-one studies met the inclusion criteria and 19 had sufficient data for meta-analysis. AD was associated with higher odds of hypertension compared with healthy controls [increased in nine of 16 studies; pooled prevalence 16·4% vs. 13·8%; random-effects regression, pooled unadjusted odds ratio (OR) 1·16, 95% confidence interval (CI) 1·04-1·30], but lower odds of hypertension compared with psoriasis [decreased in five of eight studies; 15·4% vs. 24·8% (OR 0·53, 95% CI 0·37-0·76)]. In particular, moderate-to-severe AD was associated with hypertension compared with healthy controls [increased in four of six studies; 24·9% vs. 14·7% (OR 2·33, 95% CI 1·10-4·94)]. Hypertension was commonly reported as an adverse event secondary to AD treatments, particularly systemic ciclosporin A. Limitations include lack of longitudinal studies or individual-level data, and potential confounding. CONCLUSIONS: AD, particularly moderate-to-severe disease, was associated with increased hypertension compared with healthy controls, but with lower odds than for psoriasis.


Assuntos
Dermatite Atópica , Eczema , Hipertensão , Dermatite Atópica/complicações , Dermatite Atópica/epidemiologia , Humanos , Hipertensão/complicações , Hipertensão/epidemiologia , Anamnese , Prevalência
9.
Biomed Res Int ; 2021: 9968602, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34285920

RESUMO

BACKGROUND: Chemotherapeutic drugs cause severe toxicities if administered unprotected, without proper targeting, and controlled release. In this study, we developed topotecan- (TPT-) loaded solid lipid nanoparticles (SLNs) for their chemotherapeutic effect against colorectal cancer. The TPT-SLNs were further incorporated into a thermoresponsive hydrogel system (TRHS) (TPT-SLNs-TRHS) to ensure control release and reduce toxicity of the drug. Microemulsion technique and cold method were, respectively, used to develop TPT-SLNs and TPT-SLNs-TRHS. Particle size, polydispersive index (PDI), and incorporation efficiency (IE) of the TPT-SLNs were determined. Similarly, gelation time, gel strength, and bioadhesive force studies of the TPT-SLNs-TRHS were performed. Additionally, in vitro release and pharmacokinetic and antitumour evaluations of the formulation were done. RESULTS: TPT-SLNs have uniformly distributed particles with mean size in nanorange (174 nm) and IE of ~90%. TPT-SLNs-TRHS demonstrated suitable gelation properties upon administration into the rat's rectum. Moreover, drug release was exhibited in a control manner over an extended period of time for the incorporated TPT. Pharmacokinetic studies showed enhanced bioavailability of the TPT with improved plasma concentration and AUC. Further, it showed significantly enhanced antitumour effect in tumour-bearing mice as compared to the test formulations. CONCLUSION: It can be concluded that SLNs incorporated in TRHS could be a potential source of the antitumour drug delivery with better control of the drug release and no toxicity.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Hidrogéis/química , Lipídeos/química , Substâncias Macromoleculares/química , Nanopartículas/química , Temperatura , Topotecan/uso terapêutico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Masculino , Camundongos Nus , Mucosa/efeitos dos fármacos , Mucosa/patologia , Nanopartículas/ultraestrutura , Tamanho da Partícula , Ratos Sprague-Dawley , Reto/efeitos dos fármacos , Reto/patologia , Topotecan/sangue , Topotecan/farmacocinética , Topotecan/farmacologia
10.
Sci Rep ; 10(1): 577, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31953500

RESUMO

The present study aimed to explore a new source of montmorillonite and to develop an extraction and purification protocol for its isolation from raw clay samples acquired from the Koh-e-Suleiman mountain range in Pakistan. The process involved the collection of raw clay from the source, identification and quantification of montmorillonite. Granulometric extraction and purification protocols increased the montmorillonite content from 21.8-25.1% in the raw clay to 90.1-93.9% after small-scale extraction and 85.33-89.33% on a larger scale. A techno-economic analysis highlighted the practicality and economic benefits of large-scale extraction for industrial applications. This study highlights the existence of a substantial new source of this valuable clay which is currently used across multiple industries including construction, pottery making, pharmaceuticals, cosmetics and engineering. It is intuitively expected that the large-scale extraction of the material will improve the economic condition of the region by providing employment opportunities to locals and may be a valuable resource for export.

11.
Leuk Res ; 46: 51-60, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27123834

RESUMO

Mixed lineage leukemias have a relatively poor prognosis and arise as a result of translocations between the MLL(KMT2A) gene and one of multiple partner genes. Downstream targets of MLL are aberrantly upregulated and include the developmentally important HOX genes and MEIS1, as well as multiple microRNAs (miRNAs), including the miR-17∼92 cluster. Here we examined the contribution of specific miRNAs to MLL leukemias through knockdown studies utilizing custom anti-microRNA oligonucleotides. Combinatorial treatment against miR-17-5p and miR-19a-3p of the miR-17∼92 cluster dramatically reduces colony forming ability of MLL-fusion containing cell lines relative to non-MLL acute myeloid leukemia (AML) controls. To determine the mechanism by which these miRNAs contribute to leukemia, we validated PKNOX1 as a target of both miR-17-5p and miR-19a-3p. MEIS1 and PKNOX1 are TALE domain proteins that participate in ternary complexes with HOX and PBX partners. Here we establish the competitive relationship between PKNOX1 and MEIS1 in PBX-containing complex formation and determine the antagonistic role of PKNOX1 to leukemia in a murine MLL-AF9 model. These data implicate the miR-17∼92 cluster as part of a regulatory mechanism necessary to maintain MEIS1/HOXA9 -mediated transformation in MLL leukemia, indicating that targeting multiple non-homologous miRNAs may be utilized as a novel therapeutic regimen.


Assuntos
Histona-Lisina N-Metiltransferase , Leucemia/patologia , MicroRNAs/fisiologia , Proteína de Leucina Linfoide-Mieloide , Animais , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Leucemia/etiologia , Camundongos , Proteína Meis1 , Proteínas de Neoplasias/metabolismo
13.
Artigo em Inglês | MEDLINE | ID: mdl-26736971

RESUMO

In this paper, an enhanced approach of a class E amplifier being insensitive to coil impedance variations is presented. While state of the art class E amplifiers widely being used to supply implanted systems show a strong degradation of efficiency when powering distance, coil orientation or the implant current consumption deviate from the nominal design, the presented concept is able to detect these deviations on-line and to reconfigure the amplifier automatically. The concept is facilitated by a new approach of sensing the load impedance without interruption of the power supply to the implant, while the main components of the class E amplifier are programmable by software. Therefore, the device is able to perform dynamic impedance matching. Besides presenting the operational principle and the design equations, we show an adaptive prototype reader system which achieves a drain efficiency of up to 92% for a wide range of reflected coil impedances from 1 to 40 Ω. The integrated communication concept allows downlink data rates of up to 500 kBit/s, while the load modulation based uplink from implant to reader was verified of providing up to 1.35 MBit/s.


Assuntos
Amplificadores Eletrônicos , Fontes de Energia Elétrica , Próteses e Implantes , Tecnologia sem Fio/instrumentação , Simulação por Computador , Impedância Elétrica , Humanos , Software , Análise de Ondaletas
14.
J Dairy Sci ; 97(11): 6964-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25242419

RESUMO

Lactococcus species are counted among a large and closely related group of environmental streptococci and streptococci-like bacteria that include bovine mastitis pathogenic Streptococcus, Enterococcus, and Aerococcus species. Phenotypic and biochemical identification methods can be inaccurate and unreliable for species within this group, particularly for Lactococcus spp. As a result, the incidence of Lactococcus spp. on the farm may have been historically underreported and consequently little is known about the clinical importance of this genus as a mastitis pathogen. We used molecular genetic identification methods to accurately differentiate 60 environmental streptococci and streptococci-like bacteria isolated from cows with high somatic cell count and chronic intramammary infection (IMI; >2 somatic cell scores above 4) among 5 geographically distinct farms in New York and Minnesota that exhibited an observed increase in IMI. These isolates were phenotypically identified as Streptococcus uberis and Streptococcus spp. Genetic methods identified 42 isolates (70%) as Lactococcus lactis ssp. lactis, including all 10 isolates originally phenotypically identified as Streptococcus uberis. Antibiotic inhibition testing of all Lc. lactis ssp. lactis showed that 7 isolates were resistant to tetracycline. In the present study, a predominance of Lc. lactis ssp. lactis was identified in association with chronic, clinical bovine IMI among all 5 farms and characterized antimicrobial resistance for treatment therapies. Routine use by mastitis testing labs of molecular identification methods for environmental streptococci and streptococci-like bacteria can further define the role and prevalence of Lc. lactis ssp. lactis in association with bovine IMI and may lead to more targeted therapies.


Assuntos
Infecções por Bactérias Gram-Positivas/veterinária , Lactococcus lactis/fisiologia , Mastite Bovina/epidemiologia , Mastite Bovina/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus/fisiologia , Animais , Antibacterianos/farmacologia , Bovinos , Contagem de Células/veterinária , Contagem de Colônia Microbiana/veterinária , Farmacorresistência Bacteriana , Feminino , Infecções por Bactérias Gram-Positivas/complicações , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Lactococcus lactis/classificação , Lactococcus lactis/efeitos dos fármacos , Lactococcus lactis/genética , Lactococcus lactis/isolamento & purificação , Minnesota , New York , Reação em Cadeia da Polimerase/veterinária , Infecções Estreptocócicas/complicações , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/microbiologia , Streptococcus/classificação , Streptococcus/efeitos dos fármacos , Streptococcus/genética , Streptococcus/isolamento & purificação
15.
Curr Drug Targets ; 11(7): 801-11, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20370647

RESUMO

MicroRNAs (miRNA) are small non-coding RNAs of approximately 22 nucleotides that regulate the translation and stability of mRNA to control different functions of the cell. Misexpression of miRNA has been linked to disruption of normal cellular functions, which results in various disorders including cancers such as leukemias. MicroRNA involvement in disease has been the subject of much attention and is increasing our current understanding of disease biology. Such linkages have been determined by high-throughput studies, which provide a framework for characterizing differential miRNA expression levels correlating to different cytogenetic abnormalities and their corresponding malignancies. In addition, functional studies of particular miRNAs have begun to define the effects of miRNA on predicted mRNA targets. It is clear that miRNAs can serve as molecular markers of leukemias and the hope is that they can also serve as new therapeutic targets. Studies are beginning to elucidate how to deliver therapeutic antagonists to attenuate overexpressed miRNAs and to replace underexpressed miRNAs. In this review, we: i) discuss the current understanding of miRNA function and expression in normal hematopoiesis, ii) provide examples of miRNAs that are misregulated in leukemias, and iii) evaluate the current status and potential future directions for the burgeoning field of antisense oligonucleotides and other therapeutic attempts to intervene in miRNA disregulation in leukemias.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Leucemia/diagnóstico , Leucemia/tratamento farmacológico , MicroRNAs/antagonistas & inibidores , MicroRNAs/análise , Desenho de Fármacos , Regulação Leucêmica da Expressão Gênica/genética , Hematopoese/genética , Humanos , Leucemia/genética , Modelos Genéticos , Oligonucleotídeos Antissenso/uso terapêutico
16.
J Anim Physiol Anim Nutr (Berl) ; 93(1): 35-43, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19386006

RESUMO

A number of 252, 70 week old, single comb white leghorn hens at the end of their first production cycle were divided into two groups: group-I; molted by fasting and group-II; by high dietary zinc to obtain the second and third production cycle. Sampling was carried out at 5%, peak and end of the second production cycle and at 5% and peak of the third production cycle. Serum zinc decreased at the peak of the second production cycle, while increased at the 5% of the third production cycle in zinc-molted group. Serum copper and manganese increased at the 5% and peak of the second production cycle in zinc-molted group. Egg albumin zinc and copper increased at the 5% and peak of the second as well as third production cycles in zinc-molted group. Egg albumin manganese increased at 5% during the second production cycle in fasting molted group. Egg yolk zinc increased at the peak of the second production cycle in zinc-molted group. Egg yolk copper increased at the 5% of second production cycle but decreased during the third production cycle in zinc-molted group. Egg yolk manganese increased at the 5% and at the end of the second production cycle in zinc molted group. Egg yolk manganese and iron decreased during the third production cycle in zinc-molted group. Eggshell zinc decreased at the end of the second production cycle in the zinc-molted group, while eggshell copper increased at the peak of the second as well as third production cycles in fasting molted group.


Assuntos
Galinhas/fisiologia , Ovos/análise , Muda , Oviposição/efeitos dos fármacos , Zinco/farmacologia , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas/sangue , Feminino , Privação de Alimentos , Muda/efeitos dos fármacos , Muda/fisiologia , Oviposição/fisiologia , Distribuição Aleatória , Oligoelementos/metabolismo , Zinco/administração & dosagem
17.
J Biol Chem ; 279(2): 1003-9, 2004 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-14559917

RESUMO

The aim of this study was to determine whether functional heteromeric channels can be formed by co-assembly of rat SK3 (rSK3) potassium channel subunits with either SK1 or SK2 subunits. First, to determine whether rSK3 could co-assemble with rSK2 we created rSK3VK (an SK3 mutant insensitive to block by UCL 1848). When rSK3VK was co-expressed with rSK2 the resulting currents had an intermediate sensitivity to UCL 1848 (IC50 of approximately 5 nM compared with 120 pM for rSK2 and >300 nM for rSK3VK), suggesting that rSK3 and rSK2 can form functional heteromeric channels. To detect co-assembly of SK3 with SK1, we initially used a dominant negative construct of the human SK1 subunit (hSK1YP). hSK1YP dramatically reduced the SK3 current, supporting the idea that SK3 and SK1 subunits also interact. To determine whether these assemblies were functional we created rSK3VF, an rSK3 mutant with an enhanced affinity for tetraethylammonium chloride (TEA) (IC50 of 0.3 mM). Co-transfection of rSK3VF and hSK1 produced currents with a sensitivity to TEA not different from that of hSK1 alone (IC50 approximately 15 mM). These results suggest that hSK1 does not produce functional cell-surface assemblies with SK3. Antibody-staining experiments suggested that hSK1 may reduce the number of functional SK3 subunits reaching the cell surface. Additional experiments showed that co-expression of the rat SK1 gene with SK3 also dramatically suppressed SK current. The pharmacology of the residual current was consistent with that of homomeric SK3 assemblies. These results demonstrate interactions that cause changes in protein trafficking, cell surface expression, and channel pharmacology and strongly suggest heteromeric assembly of SK3 with the other SK channel subunits.


Assuntos
Canais de Potássio Cálcio-Ativados , Canais de Potássio/química , Animais , Cálcio/metabolismo , Linhagem Celular , Relação Dose-Resposta a Droga , Eletrofisiologia , Genes Dominantes , Humanos , Imuno-Histoquímica , Concentração Inibidora 50 , Microscopia Confocal , Mutação , Canais de Potássio/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Compostos de Quinolínio/farmacologia , Ratos , Canais de Potássio Ativados por Cálcio de Condutância Baixa , Tetraetilamônio/farmacologia , Transfecção
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