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1.
Int J Life Cycle Assess ; 28(3): 221-233, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36686846

RESUMO

Purpose: There is an increasing interest in the use of non-nutritive sweeteners to replace added sugar in food and beverage products for reasons of improving consumer health. Much work has been done to understand safety of sweeteners, but very little on sustainability. To address that gap, this study presents the results of a life cycle assessment (LCA) of production of rebaudioside A 60%, 95% pure (RA60) steviol glycoside mix from Stevia rebaudiana leaf grown in Europe. Methods: An attributional cradle-to-factory-gate life cycle assessment was conducted on growing of stevia leaves and extraction of steviol glycosides in Europe. Primary data were used from a case study supply chain. Results are reported in impact categories from the ReCiPe 2016 (H) method, with focus given to global warming potential, freshwater eutrophication, water consumption, and land use. Impacts are expressed both in terms of production mass and sweetness equivalence, a common metric for understanding high intensity sweetener potency. Sweetness equivalence of RA60 is typically 200 to 300 times that of sugar. Comparison of environmental impact is made to sugar (sucrose) produced from both cane and beets. The research is part of the EU project SWEET (sweeteners and sweetness enhancers: impact on health, obesity, safety, and sustainability). Results and discussion: Global warming potential for production of RA60 was found to be 20.25 kgCO2-eq/kgRA60 on a mass basis and 0.081 kgCO2-eq/kgSE on a sweetness equivalence basis. Field production of stevia leaves was found to be the main source of impact for most impact categories, and for all four focus categories. Extraction of the RA60 was the main source of impact for the others. Leaf processing and seedling propagation were minor contributors to life cycle impact. Removal of international transport from the supply chain reduced global warming potential by 18.8%. Compared with sugar on a sweetness equivalence basis, RA60 has approximately 5.7% to 10.2% the impact for global warming potential, 5.6% to 7.2% the impact for land use, and is lower across most other impact categories. Conclusion: This is the first LCA of steviol glycoside mix RA60 produced from leaf in Europe. The results indicate that RA60 can be used to reduce environmental impact of providing a sweet taste by replacing sugar across all impact categories. However, it is important to note that specific formulations in which RA60 is used will have a bearing on the final environmental impact of any food or beverage products. For solid foods, this requires further research. Supplementary Information: The online version contains supplementary material available at 10.1007/s11367-022-02127-9.

2.
Philos Trans A Math Phys Eng Sci ; 379(2189): 20200011, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33280561

RESUMO

Laser-direct drive (LDD), along with laser indirect (X-ray) drive (LID) and magnetic drive with pulsed power, is one of the three viable inertial confinement fusion approaches to achieving fusion ignition and gain in the laboratory. The LDD programme is primarily being executed at both the Omega Laser Facility at the Laboratory for Laser Energetics and at the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory. LDD research at Omega includes cryogenic implosions, fundamental physics including material properties, hydrodynamics and laser-plasma interaction physics. LDD research on the NIF is focused on energy coupling and laser-plasma interactions physics at ignition-scale plasmas. Limited implosions on the NIF in the 'polar-drive' configuration, where the irradiation geometry is configured for LID, are also a feature of LDD research. The ability to conduct research over a large range of energy, power and scale size using both Omega and the NIF is a major positive aspect of LDD research that reduces the risk in scaling from OMEGA to megajoule-class lasers. The paper will summarize the present status of LDD research and plans for the future with the goal of ultimately achieving a burning plasma in the laboratory. This article is part of a discussion meeting issue 'Prospects for high gain inertial fusion energy (part 2)'.

3.
Appl Opt ; 59(26): 7994-8002, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32976475

RESUMO

The full-beam in-tank (FBIT) diagnostic has been deployed to directly measure the target-plane beam fluence profile, when operated at high energy, of the OMEGA Laser System at the University of Rochester's Laboratory for Laser Energetics. This paper presents the results of early measurements taken with this diagnostic and discusses an improvement that has overcome performance limitations discovered during the initial testing. The diagnostic gives new insight into the ability of the OMEGA Laser System to provide uniform fluence profiles that are consistent across all 60 beams in the laser. The ultimate goal of the FBIT diagnostic is to allow accurate assessment of the fluence uniformity on a spherical target in 60-beam implosion experiments.

4.
Phys Rev Lett ; 125(6): 065001, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32845678

RESUMO

A new class of ignition designs is proposed for inertial confinement fusion experiments. These designs are based on the hot-spot ignition approach, but instead of a conventional target that is comprised of a spherical shell with a thin frozen deuterium-tritium (DT) layer, a liquid DT sphere inside a wetted-foam shell is used, and the lower-density central region and higher-density shell are created dynamically by appropriately shaping the laser pulse. These offer several advantages, including simplicity in target production (suitable for mass production for inertial fusion energy), absence of the fill tube (leading to a more-symmetric implosion), and lower sensitivity to both laser imprint and physics uncertainty in shock interaction with the ice-vapor interface. The design evolution starts by launching an ∼1-Mbar shock into a DT sphere. After bouncing from the center, the reflected shock reaches the outer surface of the sphere and the shocked material starts to expand outward. Supporting ablation pressure ultimately stops such expansion and subsequently launches a shock toward the target center, compressing the ablator and fuel, and forming a shell. The shell is then accelerated and fuel is compressed by appropriately shaping the drive laser pulse, forming a hot spot using the conventional or shock ignition approaches. This Letter demonstrates the feasibility of the new concept using hydrodynamic simulations and discusses the advantages and disadvantages of the concept compared with more-traditional inertial confinement fusion designs.

5.
Nature ; 565(7741): 581-586, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30700868

RESUMO

Focusing laser light onto a very small target can produce the conditions for laboratory-scale nuclear fusion of hydrogen isotopes. The lack of accurate predictive models, which are essential for the design of high-performance laser-fusion experiments, is a major obstacle to achieving thermonuclear ignition. Here we report a statistical approach that was used to design and quantitatively predict the results of implosions of solid deuterium-tritium targets carried out with the 30-kilojoule OMEGA laser system, leading to tripling of the fusion yield to its highest value so far for direct-drive laser fusion. When scaled to the laser energies of the National Ignition Facility (1.9 megajoules), these targets are predicted to produce a fusion energy output of about 500 kilojoules-several times larger than the fusion yields currently achieved at that facility. This approach could guide the exploration of the vast parameter space of thermonuclear ignition conditions and enhance our understanding of laser-fusion physics.

6.
Sci Rep ; 6: 21916, 2016 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-26902912

RESUMO

The Laetoli site (Tanzania) contains the oldest known hominin footprints, and their interpretation remains open to debate, despite over 35 years of research. The two hominin trackways present are parallel to one another, one of which is a composite formed by at least two individuals walking in single file. Most researchers have focused on the single, clearly discernible G1 trackway while the G2/3 trackway has been largely dismissed due to its composite nature. Here we report the use of a new technique that allows us to decouple the G2 and G3 tracks for the first time. In so doing we are able to quantify the mean footprint topology of the G3 trackway and render it useable for subsequent data analyses. By restoring the effectively 'lost' G3 track, we have doubled the available data on some of the rarest traces directly associated with our Pliocene ancestors.


Assuntos
Antepé Humano/anatomia & histologia , Fósseis , Hominidae/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Paleontologia/métodos , Algoritmos , Animais , Fenômenos Biomecânicos , Antepé Humano/fisiologia , Marcha/fisiologia , Hominidae/fisiologia , Processamento de Imagem Assistida por Computador/instrumentação , Locomoção/fisiologia , Paleontologia/instrumentação , Software , Tanzânia , Caminhada/fisiologia
7.
J R Soc Interface ; 10(83): 20130009, 2013 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-23516064

RESUMO

Footprints are the most direct source of evidence about locomotor biomechanics in extinct vertebrates. One of the principal suppositions underpinning biomechanical inferences is that footprint geometry correlates with dynamic foot pressure, which, in turn, is linked with overall limb motion of the trackmaker. In this study, we perform the first quantitative test of this long-standing assumption, using topological statistical analysis of plantar pressures and experimental and computer-simulated footprints. In computer-simulated footprints, the relative distribution of depth differed from the distribution of both peak and pressure impulse in all simulations. Analysis of footprint samples with common loading inputs and similar depths reveals that only shallow footprints lack significant topological differences between depth and pressure distributions. Topological comparison of plantar pressures and experimental beach footprints demonstrates that geometry is highly dependent on overall print depth; deeper footprints are characterized by greater relative forefoot, and particularly toe, depth than shallow footprints. The highlighted difference between 'shallow' and 'deep' footprints clearly emphasizes the need to understand variation in foot mechanics across different degrees of substrate compliance. Overall, our results indicate that extreme caution is required when applying the 'depth equals pressure' paradigm to hominin footprints, and by extension, those of other extant and extinct tetrapods.


Assuntos
Pé/fisiologia , Locomoção , Fenômenos Biomecânicos , Antepé Humano/fisiologia , Postura , Pressão , Suporte de Carga
8.
Sex Transm Infect ; 83(3): 189-92, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17244664

RESUMO

OBJECTIVE: To evaluate the molecular typing system for Treponema pallidum using cerebrospinal fluid (CSF) specimens obtained from patients with neurosyphilis in Pretoria, South Africa. METHODS: CSF specimens were collected from 32 men and 18 women with suspected late neurosyphilis. Typing of T pallidum involved PCR amplification and restriction analysis of the tprE, G and J genes and determination of the number of 60 base pair tandem repeats within the arp gene by PCR amplification. RESULTS: Of 13 typeable specimens, 4 strain types were identified: 2i, 3e, 14a and 17e. Subtype 14a was identified in 7 specimens (53.8%), subtype 3e in 4 specimens (30.7%) and subtypes 17e and 2i in 1 specimen (7.6%) each. CONCLUSIONS: This study shows that the typing system can be applied to specimens which may contain low numbers of spirochaetes such as CSF.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , DNA Bacteriano/líquido cefalorraquidiano , Neurossífilis/diagnóstico , Treponema pallidum/classificação , Feminino , Humanos , Masculino , Neurossífilis/líquido cefalorraquidiano , Técnicas de Amplificação de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase/métodos , Sensibilidade e Especificidade , Sorodiagnóstico da Sífilis/métodos , Treponema pallidum/genética , Treponema pallidum/isolamento & purificação
9.
Brain Inj ; 19(9): 699-710, 2005 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-16195184

RESUMO

PRIMARY OBJECTIVE: Attentional deficits are common following TBI in adults. This study examined whether these skills are also vulnerable following early childhood injury, when such skills are rapidly developing. RESEARCH DESIGN: This study investigated attention 30 months post-TBI in pre-schoolers (n=56) and age-matched controls (n=26). TBI children were divided into mild, moderate and severe injury groups. METHODS AND PROCEDURE: Pre-injury data were collected at time of injury. Assessment of attention included the Continuous Performance Test, Wechsler Intelligence Scale and Personality Inventory for Children. MAIN OUTCOMES AND RESULTS: Severe TBI was associated with reduced accuracy and slowed processing, particularly on complex motor responses. Sustained attention was more intact. Parental reports indicate internalized behavioural problems and somatic complaints. CONCLUSIONS: Young children with severe TBI are at risk for severe, persisting attentional impairments. Children with mild and moderate TBI show better outcome, with pre-injury behaviour and age also predictive of attentional skills at 30 months post-injury.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/etiologia , Lesões Encefálicas/complicações , Adaptação Psicológica , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Lesões Encefálicas/psicologia , Criança , Feminino , Humanos , Testes de Inteligência , Masculino , Inventário de Personalidade , Testes Psicológicos , Desempenho Psicomotor , Índice de Gravidade de Doença , Inquéritos e Questionários
10.
J Urban Health ; 82(3): 378-88, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16000654

RESUMO

Catastrophic disasters create surge capacity needs for health care systems. This is especially true in the urban setting because the high population density and reliance on complex urban infrastructures (e.g., mass transit systems and high rise buildings) could adversely affect the ability to meet surge capacity needs. To better understand responsiveness in this setting, we conducted a survey of health care workers (HCWs) (N =6,428) from 47 health care facilities in New York City and the surrounding metropolitan region to determine their ability and willingness to report to work during various catastrophic events. A range of facility types and sizes were represented in the sample. Results indicate that HCWs were most able to report to work for a mass casualty incident (MCI) (83%), environmental disaster (81%), and chemical event (71%) and least able to report during a smallpox epidemic (69%), radiological event (64%), sudden acute respiratory distress syndrome (SARS) outbreak (64%), or severe snow storm (49%). In terms of willingness, HCWs were most willing to report during a snow storm (80%), MCI (86%), and environmental disaster (84%) and least willing during a SARS outbreak (48%), radiological event (57%), smallpox epidemic (61%), and chemical event (68%). Barriers to ability included transportation problems, child care, eldercare, and pet care obligations. Barriers to willingness included fear and concern for family and self and personal health problems. The findings were consistent for all types of facilities. Importantly, many of the barriers identified are amenable to interventions.


Assuntos
Desastres , Pessoal de Saúde/psicologia , Mão de Obra em Saúde , Adolescente , Adulto , Idoso , Feminino , Instalações de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque
11.
J Neurol Neurosurg Psychiatry ; 76(3): 401-8, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15716536

RESUMO

OBJECTIVE: To examine the contributions of injury severity, physical and cognitive disability, child and family function to outcome 30 months after traumatic brain injury (TBI) in children. DESIGN: A prospective, longitudinal, between group design, comparing function before and after injury across three levels of injury severity. SUBJECTS: One hundred and fifty children, 3.0-12.11 years old, admitted to hospital with a diagnosis of TBI. The sample was divided according to injury severity: mild (n = 42), moderate (n = 70), severe (n = 38). Children with a history of neurological, developmental, and psychiatric disorders were excluded from participation. MAIN OUTCOME MEASURES: Post injury physical function, cognitive ability (incorporating intellect, memory, and attention), behavioural and family functioning, and level of family burden. RESULTS: A dose-response relation was identified for injury severity and physical and cognitive outcome, with significant recovery documented from acute to six months after TBI. Behavioural functioning was not related to injury severity, and where problems were identified, little recovery was noted over time. Family functioning remained unchanged from preinjury to post injury assessments. The level of family burden was high at both six and 30 months after injury, and was predicted by injury severity, functional impairment, and post injury child behavioural disturbance. CONCLUSIONS: These results suggest ongoing problems for the child and significant family burden 30 months after TBI. The nature and severity of the physical and cognitive problems are closely related to injury severity, with child and family function predicted by psychosocial and premorbid factors.


Assuntos
Lesões Encefálicas/reabilitação , Transtornos Cognitivos/etiologia , Efeitos Psicossociais da Doença , Saúde da Família , Adaptação Psicológica , Adulto , Criança , Pré-Escolar , Feminino , Nível de Saúde , Humanos , Masculino , Prognóstico , Estudos Prospectivos , Índice de Gravidade de Doença
12.
Rev Sci Tech ; 23(2): 443-51, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15702712

RESUMO

Emerging infectious diseases can be defined as infections that have newly appeared in a population or are rapidly increasing in incidence or geographic range. Many of these diseases are zoonoses, including such recent examples as avian influenza, severe acute respiratory syndrome, haemolytic uraemic syndrome (a food-borne infection caused by certain strains of Escherichia coli) and probably human immunodeficiency virus/acquired immune deficiency syndrome. Specific factors precipitating the emergence of a disease can often be identified. These include ecological, environmental or demographic factors that place people in increased contact with the natural host for a previously unfamiliar zoonotic agent or that promote the spread of the pathogen. These factors are becoming increasingly prevalent, suggesting that infections will continue to emerge and probably increase. Strategies for dealing with the problem include focusing special attention on situations that promote disease emergence, especially those in which animals and humans come into contact, and implementing effective disease surveillance and control.


Assuntos
Doenças Transmissíveis Emergentes/epidemiologia , Saúde Global , Agricultura , Animais , Evolução Biológica , Comércio , Doenças Transmissíveis Emergentes/etiologia , Humanos , Indústrias , Dinâmica Populacional , Fatores de Risco , Viagem , Zoonoses/epidemiologia
13.
Infection and Immunity ; 72(7): 4290-4292, 2004.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1063415

RESUMO

Intranasal challenge of C57BL/6 mice with Streptococcus pneumoniae serotypes 6B, 14, and 23F produced colonization of the middle ear and NP. Intranasal vaccination with ethanol-killed nonencapsulated cells with adjuvant protected both sites. Of four nontoxic adjuvants tested, the cholera toxin B subunit was most effective and least nonspecifically protective


Assuntos
Animais , Camundongos , Infecções Pneumocócicas/imunologia , Infecções Pneumocócicas/prevenção & controle , Streptococcus pneumoniae/efeitos da radiação , Streptococcus pneumoniae/imunologia , Vacinas Pneumocócicas/farmacologia , Vacinas Pneumocócicas/imunologia , Adjuvantes Imunológicos/farmacologia , Doenças Nasofaríngeas/imunologia , Doenças Nasofaríngeas/microbiologia , Otopatias/imunologia , Otopatias/microbiologia , Otopatias/prevenção & controle
14.
Sex Transm Infect ; 79(3): 202-7, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12794202

RESUMO

OBJECTIVES: To determine the aetiology of genital ulcer disease (GUD) and its association with HIV infection in the mining community of Carletonville, South Africa, from two cross sectional surveys of consecutive men presenting with genital lesions during October 1993 to January 1994 and July to November 1998. METHODS: A multiplex polymerase chain reaction (M-PCR) assay combined with amplicon detection was used to identify DNA specific sequences of Treponema pallidum, herpes simplex virus (HSV), and Haemophilus ducreyi. A real time PCR assay was used to differentiate between HSV-1 and HSV-2. RESULTS: M-PCR detected T pallidum, HSV, and H ducreyi in 10.3%, 17.2%, and 69.4% of 232 GUD patients during 1993-4 and in 12.4%, 36.0%, and 50.5% of 186 GUD patients in 1998. The proportion of patients with more than one agent increased significantly from 7.3% (17/232) in 1993-4 to 16.7% (31/186) in 1998 (p <0.01). HSV-2 was detected in a higher proportion of ulcer specimens from HIV infected patients than in specimens from HIV uninfected patients during both time periods (1993-4: 26.2% v 6.7%, p <0.001; 1998: 42.1% v 29.6%, p >0.09). CONCLUSIONS: Based on two cross sectional surveys, 4 years apart, chancroid remained the leading cause of GUD in men who presented at the STD clinic with genital ulcers in the mining community of Carletonville, South Africa. The relative prevalence of primary syphilis has remained low. However, HSV-2 has emerged as a more significant cause of GUD and the proportion of GUD patients infected with more than one agent also increased significantly. HSV-2 DNA was detected in a significantly higher proportion of ulcer specimens from HIV positive patients than from HIV negative patients. No association was found between HIV infection status and the relative prevalence of chancroid or syphilis.


Assuntos
Herpes Genital/epidemiologia , Herpesvirus Humano 2 , Adulto , Cancroide/epidemiologia , Estudos Transversais , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Haemophilus ducreyi , Herpes Genital/virologia , Herpesvirus Humano 2/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Mineração , Reação em Cadeia da Polimerase/métodos , Prevalência , África do Sul/epidemiologia , Sífilis/epidemiologia , Treponema pallidum/isolamento & purificação , Úlcera/epidemiologia , Úlcera/virologia
15.
J Clin Microbiol ; 40(1): 256-8, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11773125

RESUMO

We evaluated a molecular subtyping system for Treponema pallidum for its ability to differentiate between strains obtained from male patients with primary syphilis in South Africa. Of 201 T. pallidum-positive specimens, 161 were typeable, revealing 35 subtypes. The unique subtypes identified in Durban, Cape Town, and Carletonville and the total number of subtypes suggested that the strain population was very diverse and varied geographically.


Assuntos
Reação em Cadeia da Polimerase/métodos , Sífilis/epidemiologia , Sífilis/microbiologia , Treponema pallidum/classificação , Treponema pallidum/genética , Técnicas de Tipagem Bacteriana , Estudos Transversais , DNA Bacteriano/análise , Humanos , Masculino , África do Sul/epidemiologia
16.
J Hum Hypertens ; 16(12): 819-27, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12522462

RESUMO

Obesity-associated hypertension is a common disease that involves a complex pathogenesis. Failure to control hypertension (HTN) in obese subjects provides a great threat to their renal and cardiovascular functions. The treatment of obesity-associated HTN is often difficult, and requires nonpharmacological and/or pharmacological approaches. Weight reduction is the cornerstone of the therapies of obesity-HTN, as it reverses the multiple components of its pathogenesis. When weight loss cannot be sustained or fails, pharmacological means should then be used. Angiotensin-converting enzyme inhibitors (ACEI) are the drug of choice: they can reduce blood pressure, protect the kidney and heart, and improve the metabolic abnormalities in obese subjects. Angiotensin-2 type-1 receptor blockers have a renoprotective benefit similar to ACEI, and they provide an important alternative to the use of ACEI. Diuretics are very effective in African-American obese hypertensives, but small doses should be used to avoid adverse effects on metabolic profiles. Long-acting calcium channel blockers are also effective and have the advantage of no adverse metabolic effects. Nondihydropyridine calcium channel blockers may provide additional renal and cardiovascular protective effects. The beta-adrenergic receptor blockers can cause further weight gain and metabolic abnormalities in obese subjects; therefore, careful monitoring is needed. There are few clinical data that support the efficacy and benefit of centrally acting alpha-2 agonists and alpha-adrenergic receptor antagonists in the treatment of obesity-HTN.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Hipertensão/fisiopatologia , Hipertensão/terapia , Rim/fisiologia , Obesidade/fisiopatologia , Obesidade/terapia , Ensaios Clínicos como Assunto , Humanos , Hipertensão/epidemiologia , Obesidade/epidemiologia , Fatores de Risco , Resultado do Tratamento , Estados Unidos/epidemiologia , Redução de Peso/fisiologia
17.
Exp Cell Res ; 269(2): 275-86, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11570820

RESUMO

The casein kinase I (CKI) family consists of at least seven vertebrate genes, some of which can be alternatively spliced. Previously, we have studied the four splice variants of the chicken CKIalpha gene. The four proteins differ only by the presence or absence of two peptides, a 28-amino-acid "L" insert in the catalytic domain and a 12-amino-acid "S" insert near the extreme C-terminus. Here cells were transfected with DNA encoding all four isoforms fused to the green fluorescent protein (GFP) and the localization of each protein was examined. We noted that the L insert includes the sequence PVGKRKR, which has the characteristics of a nuclear localization signal (NLS), and we show that the CKIalphaL and CKIalphaLS isoforms which contain this sequence are targeted to the nucleus, where a fraction becomes associated with nuclear speckles. In contrast the two isoforms lacking the L insert remain predominantly cytoplasmic. Mutation of the first lysine in the putative NLS to asparagine prevented the nuclear entry of GFP-CKIalphaL. Therefore different CKIalpha isoforms are targeted to different cellular compartments in a fashion modulated by alternate transcription and in these locations presumably phosphorylate and regulate different cellular substrates.


Assuntos
Núcleo Celular/metabolismo , Citoplasma/metabolismo , Proteínas Quinases/biossíntese , Proteínas Quinases/química , Células 3T3 , Processamento Alternativo , Sequência de Aminoácidos , Animais , Asparagina/química , Sequência de Bases , Western Blotting , Células COS , Caseína Quinases , Citoesqueleto/metabolismo , Proteínas de Fluorescência Verde , Proteínas Luminescentes/metabolismo , Lisina/química , Camundongos , Microscopia de Fluorescência , Modelos Genéticos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Mutação , Sinais de Localização Nuclear , Fosforilação , Plasmídeos/metabolismo , Ligação Proteica , Isoformas de Proteínas , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/metabolismo , Transfecção
18.
Adv Perit Dial ; 17: 235-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11510283

RESUMO

Acidosis has been implicated in increased protein catabolism and malnutrition of dialysis. The present study examines the effect of acid-base balance on the nutrition status of peritoneal dialysis (PD) patients. We followed 43 PD patients for one year. Blood chemistries were measured monthly. Patients were divided on the basis of subjective global assessment (SGA) into well-nourished (A), mildly-to-moderately malnourished (B), and severely malnourished (C) groups. Mean serum bicarbonate and albumin concentrations were, for group A (n = 16), 23.5 mmol/L and 3.96 g/dL respectively; for group B (n = 17), 27.2 mmol/L and 3.50 g/dL respectively; and for group C (n = 10), 25.9 mmol/L and 2.9 g/dL respectively. In group A, mean serum bicarbonate was significantly lower, and albumin concentration significantly higher as compared with the other groups. Interestingly, of 9 patients with serum HCO3 < 22 mmol/L, 6 were in group A and 2 were in group B. Of 6 patients with serum HCO3 > 29 mmol/L, 5 were in group B and 4 were in group C. The data suggest that well-nourished PD patients tend to be more acidotic. Malnutrition in alkalotic PD patients may be due to low protein intake resulting in decreased acid production; however, an effect of alkalosis on protein metabolism cannot be excluded.


Assuntos
Equilíbrio Ácido-Base , Estado Nutricional , Diálise Peritoneal , Bicarbonatos/sangue , Nitrogênio da Ureia Sanguínea , Creatinina/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Distúrbios Nutricionais/diagnóstico , Distúrbios Nutricionais/etiologia , Albumina Sérica/análise , Ureia/metabolismo
19.
FEMS Microbiol Lett ; 202(1): 67-71, 2001 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-11506909

RESUMO

A search of the gonococcal genome database using the known zinc-binding protein (znuA) sequences from Escherichia coli and Haemophilus influenzae identified an open reading frame encoding a putative gonococcal ZnuA. The consensus amino acid sequence of this open reading frame possessed a characteristic 30-amino acid histidine-rich metal-binding motif (repetitive HDH sequence) containing 43% histidine and 37% aspartic acid and glutamic acid. Subsequently, two adjacent open reading frames with homology to E. coli and H. influenzae znuB and znuC were located upstream of znuA. When partially purified from sonicated cell-free supernatants by CM-Sepharose chromatography, the mature gonococcal ZnuA had an estimated molecular mass of 38 kDa by SDS-PAGE. The presence of a DNA sequence encoding a 19-amino acid signal peptide and the solubility of the mature ZnuA suggested that this protein was located in the periplasm. Inactivation of the Neisseria gonorrhoeae F62 znuA by insertional mutagenesis resulted in a mutant that had a growth rate lower than that of the wild-type parent strain and that required high concentrations of ZnCl2 (> or = 200 microM) for optimal growth. Using a chemically defined agar medium, the gonococcal ZnuA mutant grew only in the presence of Zn(2+), whereas Mg(2+), Ca(2+), Ni(2+), Fe(2+), Cu(2+), Mn(2+) and Cd(2+) had either no effect or were growth inhibitory.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Transporte de Cátions , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/metabolismo , Zinco/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Transporte Biológico , Proteínas de Transporte/química , Proteínas de Transporte/isolamento & purificação , Clonagem Molecular , Bases de Dados de Ácidos Nucleicos , Eletroforese em Gel de Poliacrilamida , Escherichia coli/genética , Vetores Genéticos , Dados de Sequência Molecular , Neisseria gonorrhoeae/efeitos dos fármacos , Neisseria gonorrhoeae/crescimento & desenvolvimento , Fases de Leitura Aberta/genética , Homologia de Sequência , Zinco/farmacologia
20.
J Infect Dis ; 183(11): 1601-6, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11343208

RESUMO

A molecular-based subtyping system for Treponema pallidum was used during an investigation of increasing syphilis in Maricopa County, Arizona. Genital ulcer or whole blood specimens from patients with syphilis were assayed by a polymerase chain reaction (PCR) amplification of a T. pallidum DNA polymerase I gene. Positive specimens were typed on the basis of PCR amplification of 2 variable genes. In all, 41 (93%) of 44 of ulcer specimens and 4 (27%) of 15 blood specimens yielded typeable T. pallidum DNA. Twenty-four (53%) of 45 specimens were subtype 14f; other subtypes identified included 4f, 4i, 5f, 12a, 12f, 14a, 14d, 14e, and 14i. Only 2 specimens were from epidemiologically linked patients. This investigation demonstrates that multiple subtypes of T. pallidum can be found in an area with high syphilis morbidity, although 1 subtype (14f) was predominant. Four typeable specimens were from blood, a newly identified specimen source for subtyping.


Assuntos
Úlcera Cutânea/microbiologia , Sífilis/microbiologia , Treponema pallidum/genética , Arizona/epidemiologia , DNA Polimerase I/genética , DNA Bacteriano/genética , Feminino , Genitália/microbiologia , Humanos , Masculino , Epidemiologia Molecular , Razão de Chances , Manejo de Espécimes , Sífilis/sangue , Sífilis/epidemiologia
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