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1.
J Therm Biol ; 76: 1-7, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30143283

RESUMO

Feed intake (FI) level affects body heat production in thermo-neutral pigs; exposure of pigs to heat stress (HS) also increases body temperature (BT). However remains unclear whether the FI level affects the heat production of HS pigs. This study analyzed the effect of FI level on BT of 9 HS pigs (46.3 ±â€¯2.6 kg body weight) implanted with a thermometer set to register the BT at 5-min intervals into the ileum. Pigs were divided in two groups randomly allotted to two FI treatments: high FI (HFI, 1.20 kg/d), and low FI (LFI, 0.96 kg/d), according to a two-period crossover experimental design. Pigs were fed 3-times a day (0600, 1200, and 2200 h), same amount each time (400 g or 320 g). Ambient temperature (AT) ranged from 29.0 to 35.4 °C. The BT of both HFI and LFI pigs followed a similar pattern along a 24-h period, but the BT of HFI pigs was higher than that of LFI pigs (P < 0.05). Postprandial afternoon and evening BT was higher than that after the morning meal (P < 0.05). The postprandial BT increment differed between meal times and AT, but not between FI levels. The BT of HFI and LFI pigs increased up to 0.18 and 0.22 °C, 0.60 and 0.61 °C, and 0.24 and 0.35 °C after the morning, afternoon, and evening meal, respectively, compared with the preprandial BT (P < 0.05). Hence, the dissipation capacity of feeding-related body heat appears to depend on the thermal load of HS pigs before consuming their meals; presumably, the thermal load during 6-h before the morning meal (AT below 32 °C) was lower than before the evening meal (AT above 32 °C). In conclusion, FI level affects the postprandial BT of HS pigs and its magnitude is larger after the evening and afternoon meals. These data suggest that HS pigs may reduce the voluntary FI during the afternoon and evening hours.


Assuntos
Temperatura Corporal , Ingestão de Alimentos , Resposta ao Choque Térmico , Sus scrofa/fisiologia , Ração Animal , Animais , Regulação da Temperatura Corporal , Período Pós-Prandial , Temperatura
2.
Int Endod J ; 49(3): 255-70, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25816688

RESUMO

This systematic review and meta-analysis investigated the influence of the number of files (full-sequence rotary-file versus reciprocating single-file systems) used during root canal preparation on the apical extrusion of debris and its biological relationship with the occurrence of symptomatic apical periodontitis. An extensive literature research was carried out in the Medline, ISI Web of Science and Cochrane databases, for relevant articles with the keyword search strategy. Based on inclusion and exclusion criteria, two reviewers independently rated the quality of each study determining the level of evidence of the articles selected. The primary outcome for the meta-analysis was determined by the amount of debris extruded into the periapical tissue during root canal preparation with multiple- or single-file systems in four laboratory studies. Analysis of in vivo release of neuropeptides (SP and CGRP) after root canal preparation with single- or multiple-file systems was also carried out. Amongst the 128 articles initially found, 113 were excluded for being nonrelevant or not fulfilling the selection criteria. Another four articles were excluded after methodology evaluation. Finally, nine laboratory studies and two in vivo studies were included in the systematic review. Four of the laboratory studies were further included for meta-analysis that revealed greater debris extrusion after the use of single-file techniques when compared to multiple-file systems. Analysis of in vivo neuropeptide expression in the periodontal ligament suggests that the design of the instrument is more important than the number of files used. Both rotary and reciprocating single-file systems generate apical extrusion of debris in laboratory studies, or expression of neuropeptides in vivo. Available evidence is limited, but supports the fact that this inflammatory reaction is not influenced by the number of files but the type of movement and the instrument design.


Assuntos
Instrumentos Odontológicos , Periodontite Periapical/etiologia , Preparo de Canal Radicular/instrumentação , Desenho de Equipamento , Humanos , Ápice Dentário
3.
Spinal Cord ; 53(12): 887-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26238317

RESUMO

STUDY DESIGN: Two case studies. OBJECTIVES: To determine whether 6 weeks of regular pelvic floor muscle training (PFMT) can improve the strength and endurance of voluntary contractions in incomplete spinal cord injury and reduce neurogenic detrusor over-activity (NDO) and incontinence. SETTING: The London Spinal Cord Injury Centre, Stanmore, London, UK. METHODS: A 6-week programme of PFMT was conducted in two male subjects with stable supra-sacral motor incomplete (AIS C and D) spinal cord injuries. Clinical evaluations before and after training comprised measures of strength and endurance of voluntary pelvic floor contractions both objectively by anal canal-pressure measurements and subjectively using the modified Oxford grading system. NDO was determined by standard urodynamic tests of bladder function and incontinence measured by the International Consultation on Incontinence Questionnaire-Urology. RESULTS: Both subjects improved the strength and endurance of their pelvic floor muscle contractions by over 100% at the end of training. After training, Subject 1 (AIS D) was able to reduce bladder pressure during over-activity almost completely by voluntarily contracting the pelvic floor muscles. Subject 2 (AIS C) achieved a lesser reduction overall after training. Continence improved only in subject 1. CONCLUSION: These case studies provide evidence that a 6-week programme of PFMT may have a beneficial effect on promoting voluntary control of NDO and reduce incontinence in selected cases with a motor incomplete spinal cord lesion.


Assuntos
Terapia por Exercício/efeitos adversos , Músculo Liso/fisiologia , Diafragma da Pelve/fisiopatologia , Traumatismos da Medula Espinal/complicações , Bexiga Urinária Hiperativa/etiologia , Incontinência Urinária/etiologia , Área Sob a Curva , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Incontinência Urinária/reabilitação
4.
Res Sq ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38798642

RESUMO

Cryptosporidium spp. are protozoan parasites that cause severe illness in vulnerable human populations. Obtaining pure Cryptosporidium DNA from clinical and environmental samples is challenging because the oocysts shed in contaminated feces are limited in quantity, difficult to purify efficiently, may derive from multiple species, and yield limited DNA (<40 fg/oocyst). Here, we develop and validate a set of 100,000 RNA baits (CryptoCap_100k) based on six human-infecting Cryptosporidium spp. (C. cuniculus, C. hominis, C. meleagridis, C. parvum, C. tyzzeri, and C. viatorum) to enrich Cryptosporidium spp. DNA from a wide array of samples. We demonstrate that CryptoCap_100k increases the percentage of reads mapping to target Cryptosporidium references in a wide variety of scenarios, increasing the depth and breadth of genome coverage, facilitating increased accuracy of detecting and analyzing species within a given sample, while simultaneously decreasing costs, thereby opening new opportunities to understand the complex biology of these important pathogens.

5.
bioRxiv ; 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38585809

RESUMO

Cryptosporidium spp. are protozoan parasites that cause severe illness in vulnerable human populations. Obtaining pure Cryptosporidium DNA from clinical and environmental samples is challenging because the oocysts shed in contaminated feces are limited in quantity, difficult to purify efficiently, may derive from multiple species, and yield limited DNA (<40 fg/oocyst). Here, we develop and validate a set of 100,000 RNA baits (CryptoCap_100k) based on six human-infecting Cryptosporidium spp. ( C. cuniculus , C. hominis , C. meleagridis , C. parvum , C. tyzzeri , and C. viatorum ) to enrich Cryptosporidium spp. DNA from a wide array of samples. We demonstrate that CryptoCap_100k increases the percentage of reads mapping to target Cryptosporidium references in a wide variety of scenarios, increasing the depth and breadth of genome coverage, facilitating increased accuracy of detecting and analyzing species within a given sample, while simultaneously decreasing costs, thereby opening new opportunities to understand the complex biology of these important pathogens.

6.
Spinal Cord ; 51(5): 375-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23318558

RESUMO

STUDY DESIGN: Retrospective review. OBJECTIVES: The International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) assesses cutaneous sensibility through light touch (LT) and sharp-dull discrimination, referred to as pin prick (PP). This project aimed to confirm a tendency for LT to score higher than PP in SCI subjects and discuss possible reasons for such disparity. SETTING: Single site cohort study, the London Spinal Cord Injury Centre, United Kingdom. METHODS: A retrospective analysis of LT and PP scores of 99 spinal cord injury subjects at the time of discharge (median 5 months) from acute care and rehabilitation in the London Spinal Cord Injury Centre was conducted. Subjects were aged 10-88 years (median 44 years; 78 men, 74 traumatic, 25 non-traumatic). There were 40 American Spinal Injury Association (ASIA) Impairment Scale (AIS) A, 7 B, 18 C and 34 D subjects. RESULTS: A disparity (P<0.001) was found between LT (64.5±3.2, mean±s.e.) and PP (54.7±2.9) AIS sensory scores. A similar difference in score (LT>PP) was registered both for traumatic and non-traumatic injury, but was greater for incomplete than for complete injury. Despite the difference, LT was well correlated with PP (R=0.87, P<0.001). Spinal segmental level of injury was determined more frequently by PP alone (43 of 99) than by LT (10 of 99) alone. CONCLUSION: The discrepancies between LT and PP could relate to the greater complexity of the PP test or a difference in the extent of injury to the posterior columns (LT) and spinothalamic (PP) tracts. Further interpretation would benefit from additional electrophysiological sensory tests.


Assuntos
Exame Neurológico/métodos , Exame Neurológico/normas , Traumatismos da Medula Espinal/classificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tato , Adulto Jovem
7.
J Trop Med ; 2022: 4716151, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432549

RESUMO

While Tanzania is among the high TB burden countries to reach the WHO's End TB 2030 milestones, 41% of the people estimated to have had TB in 2020 were not diagnosed and notified. As part of the response to close the TB treatment coverage gap, SHDEPHA+ Kahama conducted a TB REACH active case-finding (ACF) intervention among rural and mining communities in Northwest Tanzania to increase TB/HIV case notification from July 2017 to June 2020. The intervention successfully linked marginalized mining communities with integrated TB/HIV screening, diagnostic, and referral services, screening 144,707 people for TB of whom 24,200 were tested for TB and 4,478 were tested for HIV, diagnosing 1,499 people with TB and 1,273 people with HIV (including at least 154 people with TB/HIV coinfection). The intervention revealed that community-based ACF can ensure high rates of linkage to care among hard-to-reach populations for TB. Providing integrated TB and HIV screening and diagnostic services during evening hours (Moonlight Events) in and around mining settlements can yield a large number of people with undiagnosed TB and HIV. For TB, this is true not only amongst miners but also FSW living in the same communities, who appear to be at similar or equally high risk of infection. Local NGOs can help to bridge the TB treatment coverage gap and to improve TB and HIV health outcomes by linking these marginalized groups with public sector services. Capturing the number of referrals arriving at CTCs is an important next step to identify how well the integrated TB/HIV outreach services operate and how they can be strengthened.

8.
Nat Med ; 6(8): 916-9, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10932230

RESUMO

One hallmark of Alzheimer disease is the accumulation of amyloid beta-peptide in the brain and its deposition as plaques. Mice transgenic for an amyloid beta precursor protein (APP) mini-gene driven by a platelet-derived (PD) growth factor promoter (PDAPP mice), which overexpress one of the disease-linked mutant forms of the human amyloid precursor protein, show many of the pathological features of Alzheimer disease, including extensive deposition of extracellular amyloid plaques, astrocytosis and neuritic dystrophy. Active immunization of PDAPP mice with human amyloid beta-peptide reduces plaque burden and its associated pathologies. Several hypotheses have been proposed regarding the mechanism of this response. Here we report that peripheral administration of antibodies against amyloid beta-peptide, was sufficient to reduce amyloid burden. Despite their relatively modest serum levels, the passively administered antibodies were able to enter the central nervous system, decorate plaques and induce clearance of preexisting amyloid. When examined in an ex vivo assay with sections of PDAPP or Alzheimer disease brain tissue, antibodies against amyloid beta-peptide triggered microglial cells to clear plaques through Fc receptor-mediated phagocytosis and subsequent peptide degradation. These results indicate that antibodies can cross the blood-brain barrier to act directly in the central nervous system and should be considered as a therapeutic approach for the treatment of Alzheimer disease and other neurological disorders.


Assuntos
Doença de Alzheimer/terapia , Peptídeos beta-Amiloides/imunologia , Anticorpos/administração & dosagem , Anticorpos/metabolismo , Doença de Alzheimer/imunologia , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/genética , Animais , Modelos Animais de Doenças , Humanos , Imunização , Técnicas In Vitro , Camundongos , Camundongos Transgênicos , Fagocitose , Placa Amiloide/imunologia , Placa Amiloide/patologia
9.
J Exp Med ; 175(5): 1307-16, 1992 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-1314886

RESUMO

To study the processes of thymic development, we have established transgenic mice expressing and alpha/beta T cell antigen receptor (TCR) specific for cytochrome c associated with class II major histocompatibility complex (MHC) molecules. The transgenic TCR chains are expressed by most of the thymocytes in these mice, and these cells have been shown to efficiently mature in association with Ek- and Ab-encoded class II MHC molecules. This report describes a characterization of the negative selection of these transgenic thymocytes in vivo that is associated with the expression of As molecules. Negative selection by As molecules appears to result in the deletion of a late stage of CD4/CD8 double-positive thymocytes in that there is a virtual absence of transgenic TCR bearing CD4 single-positive thymocytes. This phenotype is accompanied by the appearance of CD4/CD8 double-negative thymocytes and peripheral T cells that are functionally antigen reactive. The process of negative selection has also been investigated using an in vitro culture system. Upon presentation of cytochrome c by Eb-expressing nonthymic antigen-presenting cells, there occurs an antigen dose-dependent deletion of the majority of CD4/CD8 double-positive thymocytes. In contrast, presentation of Staphylococcal enterotoxin A by Eb in vitro results in minimal deletion of double-positive thymocytes. In addition, we use this in vitro model to examine the effects of cyclosporin A on negative selection. In contrast to its effects on mature T cells, and the findings of others in vivo, cyclosporin A does not inhibit antigen-induced deletion of double-positive thymocytes. Finally, a comparison of the antigen dose responses for thymocyte deletion and for peripheral T cell activation indicates that double-positive thymocyte recognition is more sensitive than mature T cells to antigen recognition.


Assuntos
Timo/citologia , Animais , Antígenos CD/imunologia , Antígenos CD/metabolismo , Morte Celular , Células Cultivadas , Células Clonais , Ciclosporina/farmacologia , Grupo dos Citocromos c/metabolismo , Citometria de Fluxo , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Tolerância Imunológica , Linfócitos/citologia , Linfócitos/efeitos dos fármacos , Camundongos , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Baço/citologia , Baço/imunologia , Linfócitos T/imunologia , Timo/enzimologia , Timo/metabolismo
10.
Theriogenology ; 158: 267-276, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33002770

RESUMO

Diacylglycerol acyltransferase-1 (DGAT1) is one of the DGAT enzymes that catalyzes the final step in the synthesis of triacylglycerol, which is a major component of the lipid droplets in embryos. Intracellular lipids accumulated in embryos produced in vitro have been associated with reduced cryotolerance and quality. The objective of the present study was to investigate the influence of DGAT1 inhibition on embryo development, quality, and post-vitrification survival, in addition to expression profiles of selected lipid metabolism-regulating and oxidative stress genes. Bovine cumulus-oocyte complexes were matured and fertilized in vitro and were cultured in synthetic oviduct fluid (SOF) supplemented with 5% fetal calf serum (FCS) alone (Control) or with 1, 5, 10 or 50 µM DGAT1 inhibitor (A922500®; D1, D5, D10, and D50, respectively) or 0.1% dimethyl sulfoxide (CDMSO: vehicle for DGAT1 inhibitor dilution) from 54 h post-insemination until Day 8 post insemination. No differences were found in blastocyst yield on days 7 and 8 in Control, CDMSO, D10, and D50 groups. Embryos cultured with 10 or 50 µM DGAT1 inhibitor had greater mitochondrial activity (P < 0.01), and increased number of cells (P < 0.05), while the cytoplasmic lipid content was reduced (P < 0.01), the latter associated with altered expression profiles of selected genes regulating lipid metabolism or genes related with oxidative stress (transcript abundance increased for SLC2A1 and SLC2A5 and decreased for DGAT1 and GPX1). Importantly, the survival rate of blastocysts produced with 10 µM DGAT1 was higher than that of Control, CDMSO and D50 groups at 72 h after vitrification and warming (73.8 vs 57.1, 55.9 and 56.1%, respectively, P < 0.001). In conclusion, inhibition of DGAT1 synthesis in bovine embryos produced in vitro abrogates the negative effect of FCS by decreasing their lipid content, increasing mitochondria activity and improving embryo cryotolerance, as well as favoring the expression of lipid metabolism regulating and oxidative stress-related transcripts.


Assuntos
Diacilglicerol O-Aciltransferase , Técnicas de Cultura Embrionária , Animais , Blastocisto , Bovinos , Criopreservação/veterinária , Diacilglicerol O-Aciltransferase/genética , Técnicas de Cultura Embrionária/veterinária , Fertilização in vitro/veterinária , Lipídeos
11.
J Anim Sci ; 96(4): 1419-1429, 2018 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-29471400

RESUMO

Heat stress (HS) pigs reduce their voluntary feed intake (VFI) and ingestion of indispensable amino acids (AA). Increasing the dietary crude protein (CP) content may help to correct the reduced AA intake by HS pigs, but it may further increase their body heat load. Increasing the AA intake by adding free AA to the diet does not affect the heat load of HS pigs. Two 21-d experiments were conducted. In Exp. 1, 30 pigs (31.1 ± 1.2 kg initial body weight) were used to determine the performance depression because of HS. Treatments were: thermo neutral pigs fed a 22% CP control diet (TN-C); HS pigs fed the control diet (HS-C); HS pigs fed a 14% CP, AA supplemented diet (HS-AA). HS pigs had lower ADG and Lys utilization efficiency, and consumed 20 and 25% less Lys and Thr, respectively, than the TN-C pigs (P < 0.05). In Exp. 2 (comparative slaughter), 25 pigs (33.6 ± 0.65 kg initial body weight) were used to evaluate the effect of extra dietary AA either as protein-bound or free AA on the performance and carcass traits of HS pigs. Treatments were: control wheat-SBM-free Lys, Thr and Met diet (CON); diet with 30% more CP than CON (HSxP); diet added with free AA to contain at least 25% more of each AA than the recommended level (HSxAA). Ambient temperature (AT) ranged from 27.7 to 37.7°C, and body temperature (39.9 to 41.2°C) followed a similar daily pattern as the AT did. There was no dietary treatment effect on daily feed and NE intake (P > 0.10), but the Lys, Thr, and Met intake was higher in pigs fed the HSxP or HSxAA diets than in pigs fed the CON diet (P < 0.05). The daily weight gain (ADG) was not affected (P > 0.10) but G:F tended to be higher and the Lys utilization efficiency (ADG, g/g Lys intake) tended to be lower in HSxP pigs than in CON pigs (P < 0.10). The HSxAA pigs had higher ADG (P < 0.05), and tended to have higher weight of hot carcass and leg muscle, and the weight gain of hot carcass and leg muscle than the CON pigs (P < 0.10). The weight and daily weight gain of loin muscle was higher in the HSxAA than in the HSxP pigs (P < 0.05). Kidney weight and serum urea in HSxP pigs were higher than in CON and HSxAA pigs, but spleen weight was higher in HSxAA pigs than in CON and HSxP pigs (P < 0.05). These results confirm that HS reduces the VFI, and show that increased levels of AA either as free or protein-bound do not additionally reduce the VFI of HS pigs. These also show that extra free AA supply rather than protein-bound AA better ameliorate the reduced growth performance of HS pigs.


Assuntos
Aminoácidos/administração & dosagem , Ração Animal/análise , Proteínas Alimentares/administração & dosagem , Suplementos Nutricionais , Resposta ao Choque Térmico , Suínos/fisiologia , Animais , Nitrogênio da Ureia Sanguínea , Dieta/veterinária , Ingestão de Alimentos , Feminino , Temperatura Alta , Masculino , Suínos/crescimento & desenvolvimento , Aumento de Peso/efeitos dos fármacos
12.
Aliment Pharmacol Ther ; 24 Suppl 3: 11-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16961738

RESUMO

We review the evidence that strongly suggests a role of the intestinal microbiota in the onset and perpetuation of inflammatory bowel disease (IBD). Experimental studies consisted of suppressing micro-organisms from the microbiota (using germ-free or gnotoxenic animals or antibiotics), introducing new micro-organisms or microbial components (e.g. probiotics, CpG-DNA) or selectively increasing some endogenous bacteria (e.g. using prebiotics). Intervention studies were performed in patients or animal models of spontaneous or chemically-induced colitis. Information was also obtained from observational studies that described the composition of the faecal and mucosal microbiota at various stages of the disease process and in controls. Many have used culture-independent techniques that identify bacteria based on the nucleic acid sequence of ribosomal RNA molecules. Microbiota in patients with IBD seem to be characterized by high concentrations of bacteria in contact with the mucosa, instability, the presence of high numbers of unusual bacteria and sometimes a reduction in the biodiversity. Studies searching for a generalized or localized dysbiosis in IBD are discussed, as well as those trying to identify bacterial molecules and receptors, which may be implicated in triggering the inflammatory process.


Assuntos
Infecções Bacterianas , Doenças Inflamatórias Intestinais/microbiologia , Humanos , Probióticos/uso terapêutico
14.
Prev Vet Med ; 134: 211-215, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27726887

RESUMO

In South America little is known regarding influenza virus circulating in backyard poultry and swine populations. Backyard productive systems (BPS) that breed swine and poultry are widely distributed throughout Chile with high density in the central zone, and several BPS are located within the "El Yali" (EY) ecosystem, which is one of the most important wetlands in South America. Here, 130 different wild bird species have been described, of them, at least 22 species migrate yearly from North America for nesting. For this reason, EY is considered as a high-risk zone for avian influenza virus. This study aims to identify if backyard poultry and swine bred in the EY ecosystem have been exposed to influenza A virus and if so, to identify influenza virus subtypes. A biosecurity and handling survey was applied and samples were collected from BPS in two seasons (spring 2013 and fall 2014) for influenza seroprevalence, and in one season (fall 2014) for virus presence. Seroprevalence at BPS level was 42% (95% CI:22-49) during spring 2013 and 60% (95% CI 43-72) in fall 2014. rRT-PCR for the influenza A matrix gene indicated a viral prevalence of 27% (95% CI:14-39) at BPS level in fall 2014. Eight farms (73% of rRT-PCR positive farms) were also positive to the Elisa test at the same time. One BPS was simultaneously positive (rRT-PCR) in multiple species (poultry, swine and geese) and a H1N2 virus was identified from swine, exemplifying the risk that these BPS may pose for generation of novel influenza viruses.


Assuntos
Vírus da Influenza A/isolamento & purificação , Infecções por Orthomyxoviridae/veterinária , Doenças das Aves Domésticas/virologia , Doenças dos Suínos/virologia , Animais , Chile/epidemiologia , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/virologia , Aves Domésticas , Doenças das Aves Domésticas/epidemiologia , Prevalência , Estudos Soroepidemiológicos , Suínos , Doenças dos Suínos/epidemiologia , Áreas Alagadas
15.
Artigo em Inglês | MEDLINE | ID: mdl-26319306

RESUMO

The main objective of this work was to evaluate a comprehensive two-dimensional gas chromatographic (GCxGC) coupled to quadrupole mass spectrometry (qMS) method in the field of biomarker candidates' discovery. To this purpose we developed a GCxGC-qMS method suitable for the separation of organic acids and other classes of compounds with silylable polar hydrogen such as sugars, amino-acids, and vitamins. As compared to those obtained by a widely used 1D-GC method, the urinary chromatographic profiles performed by the proposed 2D-GC method exhibit higher resolution and sensitivity, leading to the detection of up to 92 additional compounds in some urine samples including some well-known biomarkers. In order to validate the proposed method we focused on three metabolites of interest with various functional groups and polarities including CH3-malonic acid (MMA: biomarker of methylmalonic acidemia), 3-hydroxy-3-methyl-glutaric acid (3-OHMGA: biomarker of 3-hydroxy-3-methylglutaric acidemia), and phenylpiruvic acid (PhPA: marker of phenylketonuria). While these three metabolites can be considered as representative of organic acids classically determined by 1D-GC, they cannot be representative of new detected metabolites. Thus, we also focused on quinolic acid (QUIN), taken as an example of biomarker not detected at basal levels with the classical 1D GC-qMS method. In order to obtain sufficient recoveries for all tested compounds, we developed a sample preparation protocol including a step of urea removal followed by two extraction steps using two solvents of different polarity and selectivity. Recoveries with the proposed method reached more than 80% for all targeted compounds and the linearity was satisfactory up to 50µmol/L. The CVs of the within-run and within-laboratory precisions were less than 8% for all tested compounds. The limits of quantification (LOQs) were 0.6µmol/L for MMA, 0.4µmol/L for 3-OHMGA, 0.7µmol/L for PhPA, and 1µmol/L for QUIN. The LOQs of these metabolites obtained by a classical GC-MS method under the same chromatographic conditions were 5µmol/L for MMA, 4µmol/L for 3-OHMGA, 6µmol/L for PhPA while QUIN was below the limit of detection. As compared to 1D-GC, these results highlight the enhanced detectability of urine metabolites by the 2D-GC technique. Our results also show that for each new detected compound it is necessary to develop and validate an appropriate sample preparation procedure.


Assuntos
Cromatografia Gasosa/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Ácidos Quinolínicos/urina , Criança , Humanos
16.
Mol Cell Endocrinol ; 41(2-3): 237-46, 1985 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2991044

RESUMO

We have produced monoclonal antibodies which bind specifically to mouse bone cells and then selected these monoclonal antibodies for their ability to inhibit parathyroid hormone (PTH) responses in mouse cranial bone treated with the (1-34) amino terminal peptide of bovine PTH [bPTH(1-34)]. One clone, designated 3-6, characterized as an IgM(kappa), significantly inhibited the accumulation of cAMP in response to bPTH(1-34) at concentrations of hormone between 10(-9) and 10(-7) M. This antibody was subsequently isolated by gel filtration and shown to bind to intact mouse calvariae, with saturation binding occurring at 3 micrograms/ml IgM. A maximal inhibition of approximately 70% of the cAMP accumulation produced in response to 2.5 X 10(-9) M (100 ng/ml) bPTH(1-34) was obtained with 7 micrograms/ml of the purified 3-6 IgM. At this concentration of 3-6 IgM, the half-maximal dose of PTH for activation of cAMP accumulation was increased from 5 X 10(-9) M to 2 X 10(-8) M with no reduction in maximal levels of cAMP production. The utility of this antibody as an inhibitor was further tested by its ability to block the binding of an iodinated PTH analogue, 125I-[Nle8, Nle18, Tyr34]-bPTH(1-34) to mouse cranial bone. The 3-6 IgM at a concentration of 5 X 10(-8) M inhibited 70% of the specific binding of the 125I-labeled analogue. In the absence of parathyroid hormone, 2 X 10(-8) M 3-6 IgM produced a 4-fold increase in cAMP above basal levels, as compared to 40-fold maximal increases observed with PTH, indicating a partial PTH agonist activity of this antibody. When tested for effects on other hormones, 3-6 IgM did not inhibit cAMP accumulation produced in response to salmon calcitonin, epinephrine, prostaglandin E2 or cholera toxin. We propose that the 3-6 monoclonal IgM is specific for the PTH receptor or a component of the PTH receptor-adenylate cyclase system and that this or similar antibodies will serve as useful reagents for future molecular characterization of this receptor.


Assuntos
Adenilil Ciclases/imunologia , Anticorpos Monoclonais/imunologia , Osso e Ossos/imunologia , Hormônio Paratireóideo/imunologia , Receptores de Superfície Celular/imunologia , Animais , Especificidade de Anticorpos , Ligação Competitiva , Osso e Ossos/fisiologia , Linhagem Celular , Toxina da Cólera/farmacologia , AMP Cíclico/metabolismo , Dinoprostona , Epinefrina/farmacologia , Camundongos , Hormônio Paratireóideo/metabolismo , Hormônio Paratireóideo/farmacologia , Prostaglandinas E/farmacologia , Receptores de Superfície Celular/efeitos dos fármacos , Receptores de Hormônios Paratireóideos
17.
Ann N Y Acad Sci ; 920: 274-84, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11193164

RESUMO

In AD certain brain structures contain a pathological density of A beta protein deposited into plaques. The effect of genetic mutations found in early onset AD patients was an overproduction of A beta 42, strongly suggesting that overproduction of A beta 42 is associated with AD. We hypothesized that an immunological response to A beta 42 might alter its turnover and metabolism. Young PDAPP transgenic mice were immunized with A beta 1-42, which essentially prevented amyloid deposition; astrocytosis was dramatically reduced and there was reduction in A beta-induced inflammatory response as well. A beta 1-42 immunization also appeared to arrest the progression of amyloidosis in older PDAPP mice. A beta immunization appears to increase clearance of amyloid plaques, and may therefore be a novel and effective approach for the treatment of AD.


Assuntos
Doença de Alzheimer/patologia , Doença de Alzheimer/prevenção & controle , Peptídeos beta-Amiloides/imunologia , Peptídeos beta-Amiloides/metabolismo , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Doença de Alzheimer/microbiologia , Amiloidose/prevenção & controle , Animais , Formação de Anticorpos , Astrócitos/patologia , Encéfalo/patologia , Gliose , Hipocampo/patologia , Humanos , Imunoterapia , Camundongos , Camundongos Transgênicos , Neuritos/patologia
18.
J Psychiatr Res ; 16(4): 259-65, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7348279

RESUMO

A mathematical model is developed based on several assumptions to predict frequency of admission for apparent unipolar mania given that such patients have the same illness as bipolars. The model is compared with data from previous studies of unipolar mania and with data from the author's own study of 77 unipolar manic patients. The observations generally supported the model. It is concluded that the DSM III convention of classifying unipolar manics under the heading "Bipolar disorder" is upheld.


Assuntos
Transtornos Psicóticos Afetivos/diagnóstico , Transtorno Bipolar/diagnóstico , Matemática , Transtorno Bipolar/psicologia , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/psicologia , Diagnóstico Diferencial , Hospitais Psiquiátricos , Humanos , Modelos Psicológicos , Probabilidade
19.
Plant Cell Rep ; 19(2): 111-117, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30754735

RESUMO

The effect of germination conditions on the morphology of Coffea arabica L. somatic embryos mass-produced in a 1-l temporary immersion bioreactor (RITA®) was studied with emphasis on direct sowing in soil. Using germinated embryos, direct sowing resulted in a highly successful conversion of embryos into plants. A culture density above 1600 embryos per 1-l bioreactor positively affected embryo morphology by causing higher embryonic axis elongation (+4-5 mm). At this density, the addition of a high concentration of sucrose (234 mM) 2 weeks before sowing promoted an increase in effective plant conversion in soil (78%) and a vigorous vegetative growth of the resulting plants. Furthermore, direct sowing reduced handling time to 13% and shelving area requirements to 6.3% of the values obtained by conventional acclimatization of plants developed on gel media.

20.
Mar Pollut Bull ; 46(2): 224-31, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12586118

RESUMO

Herein we report on the abundance and composition of floating marine debris (FMD) in coastal waters of the SE-Pacific (off the Chilean coast) during the austral summer 2002. The observed FMD consisted mainly of plastic material (86.9%). Densities of FMD were highest between 20 degrees S and 40 degrees S, corresponding to the main concentrations of human population and activities. Low densities of FMD were found in the south between 40 degrees S and 50 degrees S (<1 item km(-2)). Generally, the highest densities were recorded in nearshore waters of major port cities (>20 items km(-2)), but occasionally high concentrations of debris were also found 50 km offshore. Densities of FMD in coastal waters of the SE-Pacific are of similar magnitudes as those found in coastal waters or inland seas of highly populated regions in the northern hemisphere, indicating the need for improved regulation and legislation in the countries of the SE-Pacific.


Assuntos
Resíduos de Alimentos , Plásticos , Movimentos da Água , Poluentes da Água/análise , Chile , Humanos , Oceano Pacífico , Eliminação de Resíduos , Estações do Ano
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