ABSTRACT
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.
ABSTRACT
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)'.
ABSTRACT
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.
ABSTRACT
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 â¼1-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.
ABSTRACT
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.
ABSTRACT
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.
Subject(s)
Forefoot, Human/anatomy & histology , Fossils , Hominidae/anatomy & histology , Image Processing, Computer-Assisted/methods , Paleontology/methods , Algorithms , Animals , Biomechanical Phenomena , Forefoot, Human/physiology , Gait/physiology , Hominidae/physiology , Image Processing, Computer-Assisted/instrumentation , Locomotion/physiology , Paleontology/instrumentation , Software , Tanzania , Walking/physiologyABSTRACT
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.
Subject(s)
Foot/physiology , Locomotion , Biomechanical Phenomena , Forefoot, Human/physiology , Posture , Pressure , Weight-BearingABSTRACT
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.
Subject(s)
Bacterial Typing Techniques/methods , DNA, Bacterial/cerebrospinal fluid , Neurosyphilis/diagnosis , Treponema pallidum/classification , Female , Humans , Male , Neurosyphilis/cerebrospinal fluid , Nucleic Acid Amplification Techniques/methods , Polymerase Chain Reaction/methods , Sensitivity and Specificity , Syphilis Serodiagnosis/methods , Treponema pallidum/genetics , Treponema pallidum/isolation & purificationABSTRACT
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.
Subject(s)
Attention Deficit Disorder with Hyperactivity/etiology , Brain Injuries/complications , Adaptation, Psychological , Attention Deficit Disorder with Hyperactivity/psychology , Brain Injuries/psychology , Child , Female , Humans , Intelligence Tests , Male , Personality Inventory , Psychological Tests , Psychomotor Performance , Severity of Illness Index , Surveys and QuestionnairesABSTRACT
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.
Subject(s)
Disasters , Health Personnel/psychology , Health Workforce , Adolescent , Adult , Aged , Female , Health Facilities , Humans , Male , Middle Aged , New York CityABSTRACT
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.
Subject(s)
Brain Injuries/rehabilitation , Cognition Disorders/etiology , Cost of Illness , Family Health , Adaptation, Psychological , Adult , Child , Child, Preschool , Female , Health Status , Humans , Male , Prognosis , Prospective Studies , Severity of Illness IndexABSTRACT
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.
Subject(s)
Communicable Diseases, Emerging/epidemiology , Global Health , Agriculture , Animals , Biological Evolution , Commerce , Communicable Diseases, Emerging/etiology , Humans , Industry , Population Dynamics , Risk Factors , Travel , Zoonoses/epidemiologyABSTRACT
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
Subject(s)
Animals , Mice , Pneumococcal Infections/immunology , Pneumococcal Infections/prevention & control , Streptococcus pneumoniae/radiation effects , Streptococcus pneumoniae/immunology , Pneumococcal Vaccines/pharmacology , Pneumococcal Vaccines/immunology , Adjuvants, Immunologic/pharmacology , Nasopharyngeal Diseases/immunology , Nasopharyngeal Diseases/microbiology , Ear Diseases/immunology , Ear Diseases/microbiology , Ear Diseases/prevention & controlABSTRACT
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.
Subject(s)
Herpes Genitalis/epidemiology , Herpesvirus 2, Human , Adult , Chancroid/epidemiology , Cross-Sectional Studies , HIV Infections/complications , HIV Infections/epidemiology , Haemophilus ducreyi , Herpes Genitalis/virology , Herpesvirus 2, Human/isolation & purification , Humans , Male , Middle Aged , Mining , Polymerase Chain Reaction/methods , Prevalence , South Africa/epidemiology , Syphilis/epidemiology , Treponema pallidum/isolation & purification , Ulcer/epidemiology , Ulcer/virologyABSTRACT
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.
Subject(s)
Polymerase Chain Reaction/methods , Syphilis/epidemiology , Syphilis/microbiology , Treponema pallidum/classification , Treponema pallidum/genetics , Bacterial Typing Techniques , Cross-Sectional Studies , DNA, Bacterial/analysis , Humans , Male , South Africa/epidemiologyABSTRACT
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.
Subject(s)
Cardiovascular Physiological Phenomena , Hypertension/physiopathology , Hypertension/therapy , Kidney/physiology , Obesity/physiopathology , Obesity/therapy , Clinical Trials as Topic , Humans , Hypertension/epidemiology , Obesity/epidemiology , Risk Factors , Treatment Outcome , United States/epidemiology , Weight Loss/physiologyABSTRACT
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.
Subject(s)
Cell Nucleus/metabolism , Cytoplasm/metabolism , Protein Kinases/biosynthesis , Protein Kinases/chemistry , 3T3 Cells , Alternative Splicing , Amino Acid Sequence , Animals , Asparagine/chemistry , Base Sequence , Blotting, Western , COS Cells , Casein Kinases , Cytoskeleton/metabolism , Green Fluorescent Proteins , Luminescent Proteins/metabolism , Lysine/chemistry , Mice , Microscopy, Fluorescence , Models, Genetic , Molecular Sequence Data , Mutagenesis, Site-Directed , Mutation , Nuclear Localization Signals , Phosphorylation , Plasmids/metabolism , Protein Binding , Protein Isoforms , Protein Structure, Tertiary , Recombinant Fusion Proteins/metabolism , TransfectionABSTRACT
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.
Subject(s)
Acid-Base Equilibrium , Nutritional Status , Peritoneal Dialysis , Bicarbonates/blood , Blood Urea Nitrogen , Creatinine/metabolism , Female , Humans , Male , Middle Aged , Nutrition Disorders/diagnosis , Nutrition Disorders/etiology , Serum Albumin/analysis , Urea/metabolismABSTRACT
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.
Subject(s)
Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Carrier Proteins/genetics , Carrier Proteins/metabolism , Cation Transport Proteins , Neisseria gonorrhoeae/genetics , Neisseria gonorrhoeae/metabolism , Zinc/metabolism , Amino Acid Sequence , Bacterial Proteins/chemistry , Bacterial Proteins/isolation & purification , Biological Transport , Carrier Proteins/chemistry , Carrier Proteins/isolation & purification , Cloning, Molecular , Databases, Nucleic Acid , Electrophoresis, Polyacrylamide Gel , Escherichia coli/genetics , Genetic Vectors , Molecular Sequence Data , Neisseria gonorrhoeae/drug effects , Neisseria gonorrhoeae/growth & development , Open Reading Frames/genetics , Sequence Homology , Zinc/pharmacologyABSTRACT
OBJECTIVE: To examine the relative contributions of injury severity, level of physical and cognitive disability, child behavior and family function to short-term outcome 6 months following traumatic brain injury (TBI) in children. DESIGN: Prospective, longitudinal, between-group design, comparing preinjury and postinjury measures of functional outcome across three levels of injury severity. SUBJECTS: One hundred and twelve children, aged 2-12 years admitted to the Royal Children's Hospital, Melbourne, with a diagnosis of TBI. The sample was divided into three groups, according to injury severity: mild TBI (n = 31), moderate TBI (n = 52) and severe TBI (n = 29). Children with a history of neurologic, developmental and psychiatric disorder were excluded from participation. MAIN OUTCOME MEASURES: Levels of postinjury functioning in the following domains: physical function, cognitive ability (incorporating intellect, memory and attention), behavioral and family functioning, and level of family burden. RESULTS: A clear dose-response relationship for physical and cognitive outcomes was found, with severe TBI associated with greater impairment of physical, intellectual, memory and attentional function. For psychosocial outcome, results were less clearly linked to injury severity. Preinjury behavioral and family functioning were closely related to postinjury function in these domains, with an interaction identified between family function and child behavior at 6 months postinjury. Family functioning remained unchanged postinjury, although level of burden was high, and predicted by injury severity, functional impairment and postinjury behavioral disturbance. CONCLUSIONS: These results suggest ongoing functional problems for the child and significant family burden 6 months following TBI. The nature and severity of physical and cognitive problems are most closely related to injury severity, with family functioning and child behavior better predicted by psychosocial and premorbid factors.