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1.
BMC Emerg Med ; 20(1): 33, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32375637

RESUMO

BACKGROUND: The Kingdom of Eswatini, a lower-middle income nation of 1.45 million in southern Africa, has recently identified emergency care as a key strategy to respond to the national disease burden. We aimed to evaluate the current capacity of hospital emergency care areas using the WHO Hospital Emergency Unit Assessment Tool (HEAT) at government referral hospitals in Eswatini. METHODS: We conducted a cross-sectional study of three government referral hospital emergency care areas using HEAT in May 2018. This standardised tool assists healthcare facilities to assess the emergency care delivery capacity in facilities and support in identifying gaps and targeting interventions to strengthen care delivery within emergency care areas. Senior-level emergency care area employees, including senior medical officers and nurse matrons, were interviewed using the HEAT. RESULTS: All sites provided some level of emergency care 24 h a day, 7 days a week, though most had multiple entry points for emergency care. Only one facility had a dedicated area for receiving emergencies and a dedicated resuscitation area; two had triage areas. Facilities had limited capacity to perform signal functions (life-saving procedures that require both skills and resources). Commonly reported barriers included training deficits and lack of access to supplies, medications, and equipment. Sites also lacked formal clinical management and process protocols (such as triage and clinical protocols). CONCLUSIONS: The HEAT highlighted strengths and weaknesses of emergency care delivery within hospitals in Eswatini and identified specific causes of these system and service gaps. In order to improve emergency care outcomes, multiple interventions are needed, including training opportunities, improvement in supply chains, and implementation of clinical and process protocols for emergency care areas. We hope that these findings will allow hospital administrators and planners to develop effective change management plans.


Assuntos
Serviço Hospitalar de Emergência/organização & administração , Equipamentos e Provisões Hospitalares/provisão & distribuição , Recursos em Saúde/provisão & distribuição , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Número de Leitos em Hospital , Estudos Transversais , Essuatíni , Hospitais Rurais , Humanos , Organização Mundial da Saúde
2.
Opt Express ; 23(13): 17067-76, 2015 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-26191715

RESUMO

Whispering gallery modes (WGMs) within microsphere cavities enable highly sensitive label-free detection of changes in the surrounding refractive index. This detection modality is of particular interest for biosensing applications. However, the majority of biosensing work utilizing WGMs to date has been conducted with resonators made from either silica or polystyrene, while other materials remain largely uninvestigated. By considering characteristics such as the quality factor and sensitivity of the resonator, the optimal WGM sensor design can be identified for various applications. This work explores the choice of resonator refractive index and size to provide design guidelines for undertaking refractive index biosensing using WGMs.

3.
Nat Genet ; 11(1): 96-8, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7550325

RESUMO

Biotinidase deficiency is an autosomal recessive inherited disorder that is characterized by neurological and cutaneous symptoms. Biotinidase-deficient children cannot recycle endogenous biotin, an essential water-soluble B vitamin. Biotin is covalently attached to epsilon-amino groups of lysyl residues of four carboxylases. These carboxylases are subsequently degraded to biocytin (biotin-epsilon-lysine). Biotinidase cleaves biocytin to biotin and lysine, thereby completing the biotin cycle. The symptoms of biotinidase deficiency can be resolved or prevented by treatment with biotin. Therefore, it is important that biotinidase deficiency is diagnosed early so that permanent neurological damage can be prevented. Many states and countries currently perform newborn screening for biotinidase deficiency. We have recently isolated and characterized the cDNA for normal human biotinidase and localized the gene to chromosome 3p25 (ref. 9). We have now identified the first mutation that causes profound biotinidase deficiency. It occurs in a distinct region of the gene that encodes the putative signal peptide. Fifty percent of symptomatic children studied have a 7-bp deletion coupled with a 3-bp insertion in at least one of their alleles of the biotinidase gene. This mutation appears to be a common cause of biotinidase deficiency in symptomatic children.


Assuntos
Amidoidrolases/genética , Alelos , Amidoidrolases/deficiência , Sequência de Bases , Biotina/metabolismo , Biotinidase , Criança , Análise Mutacional de DNA , Feminino , Genes , Humanos , Recém-Nascido , Masculino , Dados de Sequência Molecular , Mutação , Linhagem , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples
4.
Mol Pharm ; 9(11): 3190-9, 2012 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-23067245

RESUMO

Protein aggregation is a major problem for biopharmaceuticals. While the control of aggregation is critically important for the future of protein pharmaceuticals, mechanisms of aggregate assembly, particularly the role that structure plays, are still poorly understood. Increasing evidence indicates that partially folded intermediates critically influence the aggregation pathway. We have previously reported the use of the basic leucine zipper (bZIP) domain of activating transcription factor 5 (ATF5) as a partially folded model system to investigate protein aggregation. This domain contains three regions with differing structural propensity: a N-terminal polybasic region, a central helical leucine zipper region, and a C-terminal extended valine zipper region. Additionally, a centrally positioned cysteine residue readily forms an intermolecular disulfide bond that reduces aggregation. Computational analysis of ATF5 predicts that the valine zipper region facilitates self-association. Here we test this hypothesis using a truncated mutant lacking the C-terminal valine zipper region. We compare the structure and aggregation of this mutant to the wild-type (WT) form under both reducing and nonreducing conditions. Our data indicate that removal of this region results in a loss of α-helical structure in the leucine zipper and a change in the mechanism of self-association. The mutant form displays increased association at low temperature but improved resistance to thermally induced aggregation.


Assuntos
Fatores Ativadores da Transcrição/química , Fatores Ativadores da Transcrição/metabolismo , Multimerização Proteica , Valina/química , Fatores Ativadores da Transcrição/genética , Benzotiazóis , Dicroísmo Circular , Fluorescência , Humanos , Zíper de Leucina , Mutação/genética , Ressonância Magnética Nuclear Biomolecular , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Espectroscopia de Infravermelho com Transformada de Fourier , Tiazóis/química
5.
Br J Anaesth ; 109(2): 219-24, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22617093

RESUMO

BACKGROUND: Recent work suggests that increased plasma concentrations of cardiac troponin I (cTnI) are common in critically ill patients and are associated with poor outcome. We measured the frequency of increased plasma cTnI concentrations during patients' stay in a mixed medical/surgical intensive care unit (ICU) and compared our findings with hospital mortality. METHODS: Basic details, organ support, and hospital mortality were recorded for all patients treated in ICU during a 6 month period. cTnI concentrations were sampled daily for all patients, using 0.04 µg litre(-1) as the upper limit of normal, and 0.12 µg litre(-1) as an additional stratification point. RESULTS: Of 663 patients, 54% were male, with a mean (sd) age of 60 (18) yr, 65% were surgical patients, and the median Acute Physiology and Chronic Ill Health II (APACHE II) score was 15 (inter-quartile range 12-20). Increased cTnI concentrations were found in 345 patients (52%) while in ICU. One hundred and twenty patients (18%) died in hospital. cTnI concentration >0.04 µg litre(-1) was associated with reduced odds of hospital survival, independent of age, medical admission, unplanned admission, APACHE II score, mechanical ventilation, and haemofiltration (adjusted odds ratio 0.25, 95% confidence interval 0.08-0.75, P=0.014). Stratification by the degree of cTnI increase revealed an incremental trend towards a lower odds of hospital survival, including for patients with 'minor' elevations of cTnI (0.05-0.12 µg litre(-1)). CONCLUSIONS: Increased serum cTnI concentrations during ICU stay independently predicts hospital mortality, even when the threshold is low. We found a trend towards an association between 'minor' elevations in cTnI and higher in-hospital mortality.


Assuntos
Estado Terminal/mortalidade , Unidades de Terapia Intensiva , Troponina I/sangue , APACHE , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Cuidados Críticos/métodos , Feminino , Mortalidade Hospitalar , Humanos , Tempo de Internação/estatística & dados numéricos , Londres/epidemiologia , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/sangue , Isquemia Miocárdica/mortalidade , Prognóstico , Adulto Jovem
6.
Sci Rep ; 12(1): 17379, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36253461

RESUMO

Orogenic gold deposits are comprised of complex quartz vein arrays that form as a result of fluid flow along transcrustal fault zones in active orogenic belts. Mineral precipitation in these deposits occurs under variable pressure conditions, but a mechanism explaining how the pressure regimes evolve through time has not previously been proposed. Here we show that extensional quartz veins at the Garrcon deposit in the Abitibi greenstone belt of Canada preserve petrographic characteristics suggesting that the three recognized paragenetic stages formed within different pressure regimes. The first stage involved the growth of interlocking quartz grains competing for space in fractures held open by hydrothermal fluids at supralithostatic pressures. Subsequent fluid flow at fluctuating pressure conditions caused recrystallization of the vein quartz and the precipitation of sulfide minerals through wall-rock sulfidation, with some of the sulfide minerals containing microscopic gold. These pressure fluctuations between supralithostatic to near-hydrostatic conditions resulted in the post-entrapment modification of the fluid inclusion inventory of the quartz. Late fluid flow occurred at near-hydrostatic conditions and resulted in the formation of fluid inclusions that have not been affected by post-entrapment modification as pressure conditions never returned to supralithostatic conditions. This late fluid flow is interpreted to have formed the texturally late, coarse native gold that occurs along quartz grain boundaries and in open spaces. The systematic evolution of the pressure regimes in orogenic gold deposits such as Garrcon can be explained by relative movement of fault-fracture meshes across the base of the upper crustal brittle-ductile transition zone. We conclude that early vein quartz in orogenic deposits is precipitated at near-lithostatic conditions whereas the paragenetically late gold is introduced at distinctly lower pressure.

7.
Phys Med Biol ; 67(16)2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35905731

RESUMO

Cone-beam computed tomography (CBCT) imaging is becoming increasingly important for a wide range of applications such as image-guided surgery, image-guided radiation therapy as well as diagnostic imaging such as breast and orthopaedic imaging. The potential benefits of non-circular source-detector trajectories was recognized in early work to improve the completeness of CBCT sampling and extend the field of view (FOV). Another important feature of interventional imaging is that prior knowledge of patient anatomy such as a preoperative CBCT or prior CT is commonly available. This provides the opportunity to integrate such prior information into the image acquisition process by customized CBCT source-detector trajectories. Such customized trajectories can be designed in order to optimize task-specific imaging performance, providing intervention or patient-specific imaging settings. The recently developed robotic CBCT C-arms as well as novel multi-source CBCT imaging systems with additional degrees of freedom provide the possibility to largely expand the scanning geometries beyond the conventional circular source-detector trajectory. This recent development has inspired the research community to innovate enhanced image quality by modifying image geometry, as opposed to hardware or algorithms. The recently proposed techniques in this field facilitate image quality improvement, FOV extension, radiation dose reduction, metal artifact reduction as well as 3D imaging under kinematic constraints. Because of the great practical value and the increasing importance of CBCT imaging in image-guided therapy for clinical and preclinical applications as well as in industry, this paper focuses on the review and discussion of the available literature in the CBCT trajectory optimization field. To the best of our knowledge, this paper is the first study that provides an exhaustive literature review regarding customized CBCT algorithms and tries to update the community with the clarification of in-depth information on the current progress and future trends.


Assuntos
Radioterapia Guiada por Imagem , Cirurgia Assistida por Computador , Algoritmos , Tomografia Computadorizada de Feixe Cônico/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas
8.
Nat Med ; 2(2): 216-23, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8574968

RESUMO

The introduction and expression of genes in somatic cells is an innovative therapy for correcting genetic deficiency diseases and augmenting immune function. A potential obstacle to gene therapy is the elimination of such gene-modified cells by an immune response to novel protein products of the introduced genes. We are conducting an immunotherapy trial in which individuals seropositive for human immunodeficiency virus (HIV) receive CD8+ HIV-specific cytotoxic T cells modified by retroviral transduction to express a gene permitting positive and negative selection. However, five of six subjects developed cytotoxic T-lymphocyte responses specific for the novel protein and eliminated the transduced cytotoxic T cells. The rejection of genetically modified cells by these immunocompromised hosts suggests that strategies to render gene-modified cells less susceptible to host immune surveillance will be required for successful gene therapy of immunocompetent hosts.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Citotoxicidade Imunológica , Antígenos HIV/imunologia , Infecções por HIV/terapia , Imunoterapia Adotiva , Apresentação de Antígeno , Sequência de Bases , Linfócitos T CD8-Positivos/transplante , Infecções por HIV/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Dados de Sequência Molecular
10.
Rhinology ; 49(5): 538-45, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22125784

RESUMO

BACKGROUND: A symptom-based questionnaire (the `Lac-Q` questionnaire) for adult patients undergoing lacrimal drainage surgery was developed. The questionnaire yields a numerical score that can be used to assess severity of symptoms. METHODOLOGY: In this study, the questionnaire was evaluated in 17 consecutive patients undergoing 22 dacryocystorhinostomy (DCR) procedures. The questionnaire was administered pre- and postoperatively. The pathology encountered at operation was recorded. The success of surgery was judged by patient satisfaction, endoscopic evaluation of DCR stomal patency, and objective lacrimal drainage testing using the functional endoscopic dye test (FEDT). In a further group of 12 pre-operative cases, the questionnaire was repeated after 4-6 weeks but before surgery, to assess test-retest reliability in the absence of clinical change. RESULTS: The Lac-Q questionnaire was based on two broad categories of eye-specific scores and social impact scores. A numerical score, the `Lac-Q` score, was generated pre- and postoperatively. When compared to pre-operative scores, the reduction in Lac-Q scores postoperatively was significant. Postoperative scores also correlated well with objective lacrimal drainage testing using the FEDT. Analysis of symptom scores shows that the questionnaire was reliable with regard to content validity, internal consistency, test-retest reliability, and responsiveness to clinical change. CONCLUSIONS: We conclude that the Lac-Q questionnaire is a useful clinical tool to evaluate outcomes after adult lacrimal surgery.


Assuntos
Doenças do Aparelho Lacrimal/cirurgia , Inquéritos e Questionários , Adulto , Dacriocistorinostomia , Humanos , Reprodutibilidade dos Testes , Resultado do Tratamento
11.
J Exp Med ; 169(2): 369-77, 1989 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-2536065

RESUMO

Chromosomal translocations in lymphoid tumors frequently result from recombination between a normally rearranging antigen receptor gene and a normally non-rearranging second locus. The possibility that the lymphocyte recombinase apparatus plays a role in determining the position of breakage at the second locus has been a matter of controversy because of the inconsistent presence of heptamer-like recognition sequences adjoining breakpoints at this site. To further investigate this issue, sites of DNA recombination were analyzed in both the der(9) and der(7) products of t(7;9)(q34;q32), a recurrent translocation of human acute lymphoblastic leukemias (T-ALL). In each of three separate cases, the translocation has divided the TCR-beta locus, juxtaposing chromosome 9 DNA 5' to a J-region in the der(9) product and 3' to a D-region in the der(7) product, with variably sized N-insertions and small deletions detectable at the junctions. All three cases contain breakpoints in chromosome 9 DNA tightly clustered between two closely spaced, and oppositely oriented heptamer sequences, CAC(A/T)GTG, which perfectly match the consensus heptamer sequence recognized by the lymphocyte recombinase apparatus in normal antigen receptor gene rearrangement. In no case was there evidence of directly duplicated sequences in the two reciprocal products, as is often associated with recombination involving random staggered breakage of DNA. Taken together, these results support a mechanism for this particular translocation proceeding by recombinase-mediated breakage of both participating chromosomes.


Assuntos
Cromossomos Humanos Par 7 , Cromossomos Humanos Par 9 , DNA Nucleotidiltransferases/fisiologia , Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T , Leucemia-Linfoma de Células T do Adulto/genética , Recombinação Genética , Translocação Genética , Sequência de Bases , Sondas de DNA , Humanos , Mapeamento por Restrição , VDJ Recombinases
12.
BJOG ; 117(11): 1411-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20716252

RESUMO

OBJECTIVE: To monitor the effectiveness of the cervical screening programme and identify suboptimal management in order to improve patient care. DESIGN: Retrospective study. SETTING: A university hospital serving a population of 1 million people. POPULATION: All women diagnosed with a cervical cancer between 2003 and 2006. METHODS: Analysis of data from invasive cervical cancer reviews. MAIN OUTCOME MEASURE: Categorisation of cervical cancer cases according to the Invasive Cervical Cancer Audit classification. RESULTS: Eighty-seven women were diagnosed with cervical cancer during the 3-year study period. The 'lapsed attender' group accounted for the greatest number of cases (30%), followed by screen detected (26%), interval cancers (13%), never attended (12%), lost to follow-up (10%) and never invited (9%). Women who had never attended for cytology presented with higher stage disease, stage-II or above, compared with the screen-detected cases: 60% were stage II or above, compared with 13.0%, Chi-square P = 0.018. The most frequently identified screening programme problem was patient compliance, which was determined to be the principle contributing factor in 39 cases (45%) and a secondary factor in a further ten cases. CONCLUSIONS: The categorisation of cervical cancer cases has the potential of yielding invaluable information for improving programme effectiveness. Patient compliance is the greatest challenge to the screening programme, and the need for regular screening and adherence to follow-up regimens needs to be reinforced in order to maximise the efficacy of the national screening programme.


Assuntos
Adenocarcinoma/prevenção & controle , Carcinoma de Células Escamosas/prevenção & controle , Programas de Rastreamento/organização & administração , Neoplasias do Colo do Útero/prevenção & controle , Adenocarcinoma/patologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Auditoria Médica , Pessoa de Meia-Idade , Cooperação do Paciente , Estudos Retrospectivos , Reino Unido , Neoplasias do Colo do Útero/patologia , Esfregaço Vaginal , Adulto Jovem
13.
Br J Anaesth ; 105(3): 318-25, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20630889

RESUMO

BACKGROUND: Recent studies have found plasma C-reactive protein (CRP) to be a predictor of outcome after discharge from the intensive care unit (ICU). To assess the generalizability of this finding, we assessed the value of CRP on the day of ICU discharge as a predictor of unplanned ICU readmission and unexpected death within 2 weeks. Plasma albumin and white cell count at discharge were also considered as markers associated with ongoing inflammation. METHODS: This was a single-centre observational study involving a medical-surgical ICU in a university teaching hospital. Data were prospectively collected from 1487 admissions involving 1401 patients over a 12 month period. Patients' admission details and APACHE II score were collected in addition to plasma CRP, white cell count, and albumin values from the day of discharge from ICU. We assessed the difference in these variables between patients who were readmitted, who died unexpectedly, and those who did not. RESULTS: We found that 9.9% of patients discharged were either readmitted (7.0%) or died unexpectedly (2.9%). Patients who were readmitted had a lower plasma albumin concentration [20 (16, 24) vs 22 (19, 27), P<0.001] and a higher admission APACHE II score [median (inter-quartile range, IQR) 16.5 (13, 21) vs 15 (12, 18), P=0.02]. Patients who died unexpectedly on the ward were older [mean (sd): 76 (12) vs 59 (19), P<0.001] and had a higher APACHE II score [21 (17.25, 26) vs 15 (12, 18), P<0.001]. There was not a statistically significant difference in CRP concentration between patients who either required ICU readmissions or died unexpectedly on the ward and those who did not. CONCLUSIONS: In a mixed medical-surgical intensive care, plasma CRP measured at the day of discharge from intensive care is not a predictor of readmissions or deaths.


Assuntos
Proteína C-Reativa/análise , Unidades de Terapia Intensiva , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Cuidados Críticos/métodos , Métodos Epidemiológicos , Hospitais de Ensino , Humanos , Tempo de Internação , Pessoa de Meia-Idade , Alta do Paciente , Readmissão do Paciente , Prognóstico , Albumina Sérica/análise , Adulto Jovem
14.
J Cell Biol ; 133(6): 1307-19, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8682866

RESUMO

A novel gene, designated byr4, was identified in Schizosaccharomyces pombe that affects the mitotic cell cycle and shows genetic interactions with the ras1 signaling pathways. Null alleles of byr4 cause cell cycle arrest in late mitosis and permit multiple rounds of septation. The multiple septa typically divide two nuclei, but the nuclei frequently do not stain equally with 4',6-diamidino-2-phenylindole (DAPI), suggesting that byr4 is required for proper karyokinesis. Overexpression of byr4 inhibits cytokinesis, but cell cycle progression continues leading to multinucleate cells. When byr4 is overexpressed, the early steps in the cytokinesis pathway, including formation of the medial F-actin ring, occur normally; however, the later steps in the pathway, including contraction of the F-actin ring, septation, and rearrangement of the medial F-actin following mitosis, rarely occur, byr4 shows two genetic interactions with ras1. The inhibition of cytokinesis by byr4 overexpression was exacerbated by null alleles of ras1 and scd1, suggesting a link between pathways needed for cell polarity and cytokinesis. Overexpression of byr4 also partially bypasses the need for ras1 for sporulation. The electrophoretic mobility of the byr4 protein varied in response to mutants that perturb cytokinesis and karyokinesis, suggesting interactions between byr4 and these gene products. A more rapidly migrating byr4 protein was found in cells with mutations in cdc16, which undergo repeated septation, and in cdc15, which fail to form a medial F-actin ring in mitosis. A slower migrating byr4 protein was found in cells with a mutation in the beta-tubulin gene, which arrests cells at the metaphase-anaphase transition.


Assuntos
Proteínas Fúngicas/genética , Genes Fúngicos/genética , Genes Supressores/genética , Genes ras/genética , Fatores de Troca do Nucleotídeo Guanina , Proteínas Repressoras , Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces/citologia , Actinas/análise , Sequência de Aminoácidos , Proteínas de Ciclo Celular/genética , Divisão Celular/genética , Núcleo Celular/química , Polaridade Celular , DNA Fúngico/análise , Proteínas Fúngicas/análise , Proteínas Fúngicas/biossíntese , Genes cdc/genética , Mitose/genética , Dados de Sequência Molecular , Proteínas Proto-Oncogênicas/genética , RNA Fúngico/análise , RNA Mensageiro/análise , Schizosaccharomyces/genética , Schizosaccharomyces/fisiologia , Esporos Fúngicos , Proteínas ras/genética
15.
J Cell Biol ; 143(4): 935-46, 1998 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-9817752

RESUMO

The yeast alpha-1,3-mannosyltransferase (Mnn1p) is localized to the Golgi by independent transmembrane and lumenal domain signals. The lumenal domain is localized to the Golgi complex when expressed as a soluble form (Mnn1-s) by exchange of its transmembrane domain for a cleavable signal sequence (Graham, T. R., and V. A. Krasnov. 1995. Mol. Biol. Cell. 6:809-824). Mutants that failed to retain the lumenal domain in the Golgi complex, called lumenal domain retention (ldr) mutants, were isolated by screening mutagenized yeast colonies for those that secreted Mnn1-s. Two genes were identified by this screen, HOG1, a gene encoding a mitogen-activated protein kinase (MAPK) that functions in the high osmolarity glycerol (HOG) pathway, and LDR1. We have found that basal signaling through the HOG pathway is required to localize Mnn1-s to the Golgi in standard osmotic conditions. Mutations in HOG1 and LDR1 also perturb localization of intact Mnn1p, resulting in its loss from early Golgi compartments and a concomitant increase of Mnn1p in later Golgi compartments.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Glicosiltransferases/metabolismo , Complexo de Golgi/enzimologia , Manosiltransferases , Proteínas Quinases Ativadas por Mitógeno , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae , Proteínas Quinases Dependentes de Cálcio-Calmodulina/genética , Parede Celular/química , Parede Celular/enzimologia , Clonagem Molecular , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Teste de Complementação Genética , MAP Quinase Quinase Quinases , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Mutagênese/fisiologia , Concentração Osmolar , Fenótipo , Proteína Quinase C/metabolismo , Estrutura Terciária de Proteína , Pirofosfatases/metabolismo , Transdução de Sinais/fisiologia , Leveduras/enzimologia , Leveduras/genética
16.
Science ; 291(5505): 878-81, 2001 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-11157168

RESUMO

Biofilms are formed by the aggregation of microorganisms into multicellular structures that adhere to surfaces. Here we show that bakers' yeast Saccharomyces cerevisiae can initiate biofilm formation. When grown in low-glucose medium, the yeast cells adhered avidly to a number of plastic surfaces. On semi-solid (0.3% agar) medium they formed "mats": complex multicellular structures composed of yeast-form cells. Both attachment to plastic and mat formation require Flo11p, a member of a large family of fungal cell surface glycoproteins involved in adherence. The ability to study biofilm formation in a tractable genetic system may facilitate the identification of new targets for antifungal therapy.


Assuntos
Biofilmes/crescimento & desenvolvimento , Proteínas Nucleares , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/fisiologia , Ágar , Adesão Celular , Meios de Cultura , Proteínas Fúngicas/genética , Proteínas Fúngicas/fisiologia , Genes Fúngicos , Glucose , Lipoproteínas/fisiologia , Sistema de Sinalização das MAP Quinases/genética , Sistema de Sinalização das MAP Quinases/fisiologia , Fator de Acasalamento , Glicoproteínas de Membrana , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , Peptídeos/fisiologia , Feromônios , Plásticos , Ploidias , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Transativadores/genética , Transativadores/fisiologia
17.
Int J Clin Pract ; 63(12): 1785-91, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19930335

RESUMO

BACKGROUND: The current paradigm for cardiovascular risk screening is one of screen and treat; i.e. a risk calculation is used to screen the population to determine who should receive therapy. This is marginally effective with somewhere between 199 and 999 people receiving lipid-lowering therapy and consequently being exposed to the drug-related risk without receiving any benefit. HYPOTHESIS: New evidence suggests that a diagnostic test could be applied to decide which patients will benefit from treatment. CONCLUSION: Changing the paradigm from 'screen and treat' to 'screen, diagnose and treat' could save large amounts of money by avoiding drugs and could prevent many people from being exposed to side effects.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico , Doença das Coronárias/sangue , Doença das Coronárias/prevenção & controle , Doença das Coronárias/terapia , Humanos , Hipolipemiantes/efeitos adversos , Hipolipemiantes/uso terapêutico , Medição de Risco , Fatores de Risco , Sensibilidade e Especificidade
18.
J Obstet Gynaecol ; 29(4): 337-9, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19835505

RESUMO

SUMMARY: The reported uptake of the intrauterine device (IUD) as emergency contraception is very low despite its superior efficacy when compared with levonorgestrel emergency contraception. A prospective study was conducted to investigate the methods of emergency contraception offered to and accepted by women attending South Staffordshire Sexual Health Clinics. A total of 240 women attended the clinic for emergency contraception during the 2-month study period. The IUD as a method of emergency contraception was not offered to the majority of women presenting within 72 h of an episode of unprotected intercourse. Nulliparous women presenting before 72 h were significantly less likely to be offered an IUD compared with parous women, p < 0.01. This study shows that the IUD is not offered to the majority of patients, in particular nulliparous women, attending for emergency contraception. Also, the low rate of the uptake of the emergency IUD is related, at least in part, to the counselling patients receive from clinicians.


Assuntos
Instituições de Assistência Ambulatorial/estatística & dados numéricos , Anticoncepção Pós-Coito/métodos , Anticoncepção Pós-Coito/estatística & dados numéricos , Dispositivos Intrauterinos/estatística & dados numéricos , Aconselhamento/estatística & dados numéricos , Feminino , Humanos , Gravidez , Estudos Prospectivos , Infecções Sexualmente Transmissíveis/epidemiologia , Reino Unido/epidemiologia , Adulto Jovem
19.
Sci Rep ; 9(1): 20282, 2019 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-31889063

RESUMO

Timber is the only widely used construction material we can grow. The wood from which it comes has evolved to provide structural support for the tree and to act as a conduit for fluid flow. These flow paths are crucial for engineers to exploit the full potential of timber, by allowing impregnation with liquids that modify the properties or resilience of this natural material. Accurately predicting the transport of these liquids enables more efficient industrial timber treatment processes to be developed, thereby extending the scope to use this sustainable construction material; moreover, it is of fundamental scientific value - as a fluid flow within a natural porous medium. Both structural and transport properties of wood depend on its micro-structure but, while a substantial body of research relates the structural performance of wood to its detailed architecture, no such knowledge exists for the transport properties. We present a model, based on increasingly refined geometric parameters, that accurately predicts the time-dependent ingress of liquids within softwood timber, thereby addressing this long-standing scientific challenge. Moreover, we show that for the minimalistic parameterisation the model predicts ingress with a square-root-of-time behaviour. However, experimental data show a potentially significant departure from this [Formula: see text] behaviour - a departure which is successfully predicted by our more advanced parametrisation. Our parameterisation of the timber microstructure was informed by computed tomographic measurements; model predictions were validated by comparison with experimental data. We show that accurate predictions require statistical representation of the variability in the timber pore space. The collapse of our dimensionless experimental data demonstrates clear potential for our results to be up-scaled to industrial treatment processes.

20.
J Appl Microbiol ; 105(6): 1973-81, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19120644

RESUMO

AIMS: To identify factors associated with the Staphylococcus aureus pine-oil disinfectant-reduced-susceptibility (PD(RS)) mechanism and to describe one possible PD(RS) model. METHODS AND RESULTS: Comparative genomic sequencing (CGS) and microarray analysis were utilized to detect mutations and transcriptome alterations that occur in a S. aureus PD(RS) mutant. Mutant analysis, antimicrobial gradient plates, growth studies and 3-hydroxy-3-methylglutaryl coenzyme A synthase assays were then performed to confirm the biological consequences of the 'omics' alterations detected in a PD(RS) mutant. CGS uncovered three mutations in a PD(RS) mutant in a(n): alcohol dehydrogenase (adh), catabolite control protein A (ccpA) and an NADPH-flavin oxidoreductase (frp). These mutations lead to increased growth rates; increased transcription of an NAD-dependent D-lactate dehydrogenase gene (ddh); and increased flux through the mevalonate pathway. PD(RS) mutants demonstrated reduced susceptibility to bacitracin and farnesol, and one PD(RS) mutant displayed upregulation of bacA, a bacitracin-resistance gene. Collectively, this evidence demonstrates altered undecaprenol metabolism in PD(RS) mutants. CONCLUSIONS: The PD(RS) mechanism proposed results from increased catabolic capabilities and increased flux through the mevalonate pathway as well as altered bactoprenol physiology. SIGNIFICANCE AND IMPACT OF THE STUDY: A novel mechanism that bacteria utilize to overcome the killing effects of PD formulations is proposed that is unique from the PD(RS) mechanism of the enterobacteraciae.


Assuntos
Desinfetantes/farmacologia , Farmacorresistência Bacteriana/genética , Pinus/química , Óleos de Plantas/farmacologia , Staphylococcus aureus/genética , Proteínas de Bactérias/genética , Análise Mutacional de DNA , Farmacorresistência Bacteriana/fisiologia , Hidroximetilglutaril-CoA Sintase/metabolismo , Lactato Desidrogenases/genética , Lactato Desidrogenases/metabolismo , Análise em Microsséries , Testes de Sensibilidade Microbiana , Proteínas Repressoras/genética , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia
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