Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Br Poult Sci ; 65(1): 52-61, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37861101

RESUMO

1. The effects of limestone particle size on growth performance, gastrointestinal tract (GIT) traits, ileal morphology, duodenal gene expression of calbindin, apparent ileal digestibility coefficients (AIDC) of calcium (Ca) and phosphorus (P) and tibia characteristics in broilers and pullets were assessed in broilers and pullets. These birds have different growth rates and likely different responses to parameters, such as particle size.2. A total of 240 chicks aged one day, 120 Ross 308 female broilers, and 120 Hy-Line pullets were allocated randomly into four treatments in a 2 × 2 factorial arrangement with two bird types (broilers vs. pullets) and two limestone particle sizes (<0.5 mm versus 1-2 mm) to give six replicates containing 10 chicks in each from 1 to 21 d of age.3. Feed intake and weight gain were greater (P < 0.001) and feed per gain (FCR) was better (P < 0.001) in broilers compared to pullets from 1 to 21 d of age. Greater villus width (P < 0.01), villus height (P < 0.001) and crypt depth (P < 0.01) were seen for broilers compared to pullets.4. Pullets fed coarse Ca particles had higher calbindin gene expression at 21 d of age (P = 0.05). Both AIDC of Ca and P were higher (P < 0.001) in broilers compared to pullets. The AIDC of Ca from 0.463 to 0.516 was increased (P < 0.05) by feeding coarse limestone particles. A significant interaction was found between bird type and limestone particle size (P < 0.01), where pullets fed coarse Ca particles had higher bone P concentration in tibia than broilers.5. Broilers had better ileum absorptive capacity and growth performance compared to pullets. The AIDC of Ca and P was higher in broilers than in pullets. Increased limestone particle size elevated villus height, AIDC of Ca and concentration of P in the tibia.


Assuntos
Carbonato de Cálcio , Cálcio , Feminino , Animais , Galinhas/genética , Tamanho da Partícula , Fósforo , Cálcio da Dieta , Íleo , Calbindinas
2.
J Microsc ; 282(1): 3-12, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33047824

RESUMO

In this study, the average diameter of the grown CNTs on Ni-Cu NPs @ a-C:H substrates were increased by increasing of Cu content. The obtained results indicated that by increase of Cu content, all films exhibited high-absorption spectra; therefore, we were facing an increase in the energy gap of films. The values of dT/dλ and dR/dλ measurements for grown CNTs with 75% Cu shown that maximum values of optical band gap correspond to with values of 2.48 eV and 2.90 eV, respectively. It can be seen that with increase of average diameter of the grown CNTs,  the values of Urbach energy of films were increased. The RBS and EDAX measurements were confirmed presence of Ni and Cu atoms into films. The films deposited with 75% Cu were more smooth. Films deposited with 75% Cu have more disordered. Films deposited with 75% Cu atoms have maximum values of the oscillator strength f and the dispersion energy Ed about of 0.108 eV2 and 0.0543 eV, respectively.

3.
Cell Mol Biol (Noisy-le-grand) ; 62(3): 20-4, 2016 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-27064869

RESUMO

A protective response against tetanus toxin and toxoid demands efficient specific T cell and B cell responses. Tetanus neurotoxin (TeNT), a 150 kDa polypeptide, is the main cause of tetanus disease. TeNT consists of two structurally distinct chains, a 50 kDa N-terminal light (L) and a 100 kDa C-terminal heavy (H) chain. C-terminal heavy (H) chain (fragment C) has two sub-domains named as proximal HCN and carboxy sub-domain or HCC. Beside neural binding property, HCC has been recently found as an immunodominant module of TeNT. In the present study, we investigated the effects of recombinant HCC (rHCC) on the expression of lineage specific transcription factors and secretion of a panel of functional cytokines including IFN-γ, IL-4, and IL-17 from purified human T cells. Our results revealed that T-bet transcript level, as TH1 specific transcription factor, was significantly increased in the cells treated with 10 and 20 µg/ml of rHCC following 48 h treatment(p<0.05). Treated purified human T cells with rHCC showed significant increase in IFN-γ mRNA level and cytokine secretion, but not IL-4 and IL-17, following 48 h treatment. In conclusion, our results showed that treatment of T cells with r HCC resulted in development of Th1 lineage phenotype, which might lead to a specific and protective antibody mediated response against tetanus toxin.


Assuntos
Clostridium tetani/imunologia , Interferon gama/imunologia , Interleucina-17/imunologia , Metaloendopeptidases/imunologia , Linfócitos T/microbiologia , Toxina Tetânica/imunologia , Tétano/imunologia , Adulto , Humanos , Interferon gama/genética , Interleucina-4/imunologia , RNA Mensageiro/genética , Proteínas Recombinantes/imunologia , Proteínas com Domínio T/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo , Tétano/genética , Tétano/microbiologia , Ativação Transcricional
4.
BMJ Mil Health ; 169(6): 488-492, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34772689

RESUMO

INTRODUCTION: The COVID-19 pandemic has posed major challenges for infection control within training centres, both civilian and military. Here we present a narrative review of an outbreak that occurred at the Royal Military Academy Sandhurst (RMAS) in January-March 2021, in the context of the circulating, highly transmissible SARS-CoV-2 variant B.1.1.7. METHODS: Testing for SARS-CoV-2 was performed using a combination of reverse transcriptase PCR and Lateral Flow Devices (LFDs). Testing and isolation procedures were conducted in line with a pre-established symptom stratification system. Genomic sequencing was performed on 10 sample isolates. RESULTS: By the end of the outbreak, 185 cases (153 Officer Cadets, 32 permanent staff) had contracted confirmed COVID-19. This represented 15% of the total RMAS population. This resulted in 0 deaths and 0 hospitalisations, but due to necessary isolation procedures did represent an estimated 12 959 person-days of lost training. 9 of 10 (90%) of sequenced isolates had a reportable lineage. All of those reported were found to be the Alpha lineage B.1.1.7. CONCLUSIONS: We discuss the key lessons learnt from the after-action review by the Incident Management Team. These include the importance of multidisciplinary working, the utility of sync matrices to monitor outbreaks in real time, issues around Officer Cadets reporting symptoms, timing of high-risk training activities, infrastructure and use of LFDs. COVID-19 represents a vital learning opportunity to minimise the impact of potential future pandemics, which may produce considerably higher morbidity and mortality in military populations.


Assuntos
COVID-19 , Militares , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , Pandemias , Surtos de Doenças
5.
Poult Sci ; 96(3): 581-592, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-27578883

RESUMO

The effects of including 3% sunflower hulls (SFH) in the diet on growth performance, nutrient retention (TTAR), and gastrointestinal tract (GIT) traits were studied in chicks from zero to 21 d of age. Four treatments that resulted from the combination of 2 chicken lines (female broilers vs. brown pullets) and 2 levels of SFH (zero vs. 3%) were used. The control diet contained 2,980 kcal AMEn/kg, 1.25% digestible Lys, and 8.7% neutral detergent fiber. The experimental diet included 3% SFH at the expense (wt:wt) of the whole diet. Growth performance, TTAR of nutrients, and the AMEn of the diet were greater (P = 0.097 to P < 0.001) in broilers than in pullets. In absolute terms, all the organs of the GIT were heavier (P < 0.001) and the small intestine and cecum were longer (P < 0.001) in broilers than in pullets. At 21 d of age, however, the relative weight (% BW) of all the organs of the GIT (P < 0.001) and the relative length (cm/kg BW) of the small intestine and cecum (P < 0.01) were greater in pullets. Gizzard pH (P < 0.001), total short chain fatty acids concentration in the cecum (P = 0.098), and villus height (P < 0.001) and crypt depth (P < 0.05) of the ileum mucosa were higher in broilers. The inclusion of SFH increased (P < 0.05) the AMEn content of the diet but did not affect bird performance, moisture content of the excreta, or the concentration and profile of fatty acids in the cecum. Dietary SFH increased gizzard weight and reduced gizzard pH (P < 0.001) at both ages. In conclusion, broilers had better growth performance, nutrient retention, and ileum absorptive capacity than pullets. The inclusion of 3% SFH at the expense of the control diet did not have any negative effect on chick performance and, in fact, increased gizzard weight, reduced gizzard pH, and improved the energy content of the diet.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Galinhas/fisiologia , Dieta/veterinária , Digestão , Trato Gastrointestinal/fisiologia , Helianthus , Ração Animal/análise , Animais , Galinhas/crescimento & desenvolvimento , Trato Gastrointestinal/crescimento & desenvolvimento , Sementes
6.
J Am Soc Mass Spectrom ; 5(8): 740-7, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24222001

RESUMO

Two isomeric oligodeoxynucleotide hexamers, 5'-d(N-6meATGCAT)-3' and 5'-d(ATGSmeCAT)-3', were subjected to analysis by electrospray and ion trap mass spectrometry. In the case of the isomer with a modified adenine, location of the modified base in the sequence was straightforward and a triple mass spectrometry experiment provided information on the identity of the modification. In contrast, the isomer with the methylated cytosine did not yield definitive information on the location or identity of the modification. Tandem mass spectrometry data in this case could indicate that the modification was present on either the third or fourth nucleoside. The two isomers represent extremes in the facility with which modified bases can be identified and located in a small oligonucleotide via multiple mass spectrometry of multiply charged anions. A preference for loss of particular bases strongly influences which structurally diagnostic ions are formed upon collisional activation. The likelihood for locating and identifying a modified base is dependent, therefore, upon the likelihood that the base is lost directly from the parention.

7.
J Am Soc Mass Spectrom ; 6(2): 102-13, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24222072

RESUMO

Deoxymononucleoside and deoxydinucleoside monophosphate anions formed by electrospray have been subjected to ion trap collisional activation. The threshold for decomposition via loss of base is significantly lower for the deoxymononucleoside 3'-monophosphates than for the corresponding 5'-monophosphates, which indicates that the presence of a charged 3' phosphate group facilitates base loss. The behavior of the bases among each class of isomers shows slight variation in threshold and tandem mass spectrometry efficiency with tile notable exception of 2'-deoxyguanosine 5'-monophosphate. This ion is exceptionally stable toward decomposition via base loss, which reflects a strong hydrogen bonding interaction between the base and the phosphate group. All dinucleotides fragment via similar mechanisms, but the propensity for neutral base loss relative to loss of a charged base is highly dependent on the identities of both the 5' and 3' bases. The behavior of the dinucleotides under collisional activation conditions supports the proposal that base loss proceeds via a proton-bound dimer intermediate in which loss of the charged base directly competes with loss of the neutral base. Application of the kinetic method allows for quantitative predictions of the differences of the gas-phase acidities of the dimer components.

8.
Iran Red Crescent Med J ; 13(8): 574-7, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22737528

RESUMO

BACKGROUND: As a performance evaluating program, healthcare indicators of the Islamic Republic of Iran at the end year of the 4th five-year socioeconomic strategic plan (2008) were evaluated in comparison with the same indicators at the 1st year of the 9th government (2004). METHODS: The indicators were selected with the Delphi technique among the published indicators in the two period of time in 41 universities and in the country. Data gathering was done on the current health information system and were statistically analyzed assessing their trends. RESULTS: The provinces of Sistan and Baluchistan (3.4%), Kerman (2.84%), Hormozgan (2.83%), Tehran (2.63%) and Qom (2.07%) had the highest rate of population growth over these years. Improving access to primary health care (PHC) in rural areas in Iran was evident during these years. The average hospital bed index in 1998 was one bed per 1000 population in the country and it was 1.62 in 2008. This Index was the highest in the province of Yazd and lowest in Ilam during both periods. CONCLUSION: A significant ascending trend was observed for indicators in all medical universities. A promotion in healthcare indicators in the lesser developed provinces seems necessary.

9.
Anal Chem ; 66(20): 3416-22, 1994 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-7978315

RESUMO

Evidence for the accumulation and storage of ionized duplex DNA molecules in a quadrupole ion trap is presented. Aqueous solutions of complementary single-strand molecules of DNA were annealed to form duplexes in solution and subjected to electrospray ionization. The ions liberated in this process were transported through an atmosphere/vacuum interface and injected into a quadrupole ion trap operated with a bath gas present at a pressure of 1 mTorr. Despite the roughly 2 order of magnitude poorer signal levels noted for electrospray of aqueous solutions relative to those observed for single-strand oligonucleotides in methanol solutions, aqueous solutions were used to avoid denaturing the duplexes. Ion trap mass spectra are reported here for duplexes consisting of two complementary 20-mer single strands and two complementary 10-mers. Tandem mass spectrometry results are also reported for the 10-mer duplex. These results are significant in that they indicate that the ions are kinetically stable under the ion injection, storage, and mass analysis conditions of the quadrupole ion trap operated with a relatively high pressure of bath gas. The tools of ion trap mass spectrometry can therefore be applied to this important class of compounds.


Assuntos
DNA/análise , DNA/química , Sequência de Bases , Fenômenos Químicos , Físico-Química , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Íons , Dados de Sequência Molecular
10.
Anal Chem ; 68(23): 4228-36, 1996 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-8984892

RESUMO

To characterize combinatorial chemical libraries of small drug compounds, an automated column switching system incorporating an immunoaffinity extraction (IAE) column and two reversed-phase HPLC columns was coupled to a triple-quadrupole mass spectrometer. A Protein G column and antibodies to benzodiazepines were used to screen library components. A pH change in the mobile phase eluted the benzodiazepine-antibody complexes onto a C-18 restricted access media (RAM) column, thereby separating the selected benzodiazepines from the antibody. In a final step, backflushing the RAM column eluted the benzodiazepines onto a C-8 analytical reversed-phase column for separation before detection and preliminary structural characterization using ion spray mass spectrometry (MS) and tandem mass spectrometry (MS/ MS). A known 19-component library and an unknown 20-component library were analyzed. Full-scan IAE/LC/ LC/MS and IAE/LC/LC/MS/MS chromatograms suggested the feasibility of this combination of techniques, although the antibodies used were not highly specific. Inspection of MS/MS spectra of components in the unknown library compared to the MS/MS spectrum of a known standard (chlordiazepoxide) identified a subclass of benzodiazepines. Productions of the known standard and an unknown benzodiazepine were successively captured and fragmented (MSn experiments) using an iontrap mass spectrometer off-line, which confirmed that the unknown was an analogue of chlordiazepoxide.


Assuntos
Benzodiazepinas/química , Cromatografia de Afinidade/métodos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos
11.
Anal Chem ; 72(16): 3853-9, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10959973

RESUMO

Since selective inhibition of the inducible form of cyclooxygenase (COX-2) might retain all the benefits of classical nonsteroidal antiinflammatory agents while avoiding the major side effects associated with inhibition of the constitutive isoform COX-1, COX-2 has become an important target for the discovery and development of new antiinflammatory drugs. To aid in the discovery and characterization of such selective inhibitors, we have applied a mass spectrometry-based screening technique, pulsed ultrafiltration mass spectrometry, using COX-2 as the target. In a blind study, 18 samples enriched with one or more inhibitors of COX-2 were evaluated. The matrixes for the test samples consisted of DMSO, r DMSO solutions of a plant extract, or a bacterial fermentation broth extract. The composition of the samples was unknown during the assays, as were the concentrations of the COX-2 inhibitors. A soluble recombinant form of human COX-2 was incubated with each sample, and then an aliquot of each mixture was injected into the stirred ultrafiltration chamber fitted with a 30000 MW cutoff ultrafiltration membrane. After the unbound and weakly bound compounds were washed away, the ligand-receptor complexes were disrupted using an acidified 10% methanol solution. The released ligands were trapped on a C18 cartridge and then identified using liquid chromatography-negative ion electrospray mass spectrometry with the trapping cartridge as the HPLC column. Neither the plant matrix nor the fermentation broth extract were found to interfere with the assay. Two or three ligands for COX-2 were identified in each sample, which included polar and nonpolar compounds and inhibitors with IC50 values ranging from 100 microM to 10 nM.


Assuntos
Inibidores de Ciclo-Oxigenase/química , Isoenzimas/efeitos dos fármacos , Espectrometria de Massas/métodos , Prostaglandina-Endoperóxido Sintases/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase/farmacologia , Humanos , Proteínas de Membrana , Ultrafiltração
12.
Anal Biochem ; 230(2): 205-14, 1995 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-7503409

RESUMO

Recent advances in molecular biology are making it possible to diagnose genetic diseases and identify pathogens through the analysis of DNA. As clinical applications for molecular diagnosis increase, rapid, reliable methods for determination of DNA size will be needed. Mass spectrometry offers the potential of analyzing amplified DNA quickly and reliably, without the need for gel-based separation and sample labeling steps that are conventionally employed. Both electrospray ionization and matrix-assisted laser desorption/ionization have been evaluated for the size analysis of DNA using both synthetic oligonucleotides and PCR-amplified samples corresponding to bases 1626 to 1701 of the cystic fibrosis transmembrane conductance regulator gene. Both technologies have been demonstrated to have mass range and sensitivity required for the analysis of PCR-amplified DNA in this size range using minimal sample preparation. Steps required to incorporate either ionization technique into a reliable analytical scheme for the rapid, routine analysis of DNA are outlined.


Assuntos
DNA/análise , Reação em Cadeia da Polimerase , Sequência de Bases , Dados de Sequência Molecular , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA