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1.
J Environ Radioact ; 196: 153-163, 2019 Jan.
Article in English | MEDLINE | ID: mdl-28789811

ABSTRACT

Nuclear sites around the world are being decommissioned and remedial actions are being undertaken to enable the sites or parts of the sites to be reused. Although this is relatively straightforward for most sites, experience has suggested that preventative action is needed to minimise the impact of remediation activities on the environment and the potential burden to future generations. Removing all contamination in order to make a site suitable for any use generates waste and has associated environmental, social and economic detriments and benefits that should be taken into account. Recent experience of OECD Nuclear Energy Agency (NEA) member countries in the remediation of contaminated land, predominantly contaminated soil and groundwater, on nuclear sites during decommissioning has been assessed by an NEA task group. The experience was used to identify strategic considerations for nuclear site remediation, to consider the application of sustainability principles to nuclear site remediation, to describe good practice, and to make recommendations for further research and development. The key aspects that were identified were that 1) site remediation should be sustainable by resulting in an overall net benefit; and 2) an adaptive approach is essential in order to take into account the inherent uncertainty associated with the decommissioning and site remediation timescales. A report describing the findings was published by OECD/NEA in 2016. The conclusions provide insights to decision makers, regulators, implementers and stakeholders involved in nuclear site decommissioning so that they can achieve sustainable remediation of nuclear sites, now and in the future.


Subject(s)
Environmental Restoration and Remediation , Nuclear Power Plants , Environmental Policy
2.
HIV Med ; 19(1): 1-6, 2018 01.
Article in English | MEDLINE | ID: mdl-28657199

ABSTRACT

OBJECTIVES: The National Health Service in England (NHS England) does not provide pre-exposure prophylaxis (PrEP) against HIV, forcing people to purchase generic versions on the internet. However, there are concerns about the authenticity of medicines purchased online. We established an innovative service offering plasma tenofovir (TFV) and emcitrabine (FTC) therapeutic drug monitoring for people buying generic PrEP online, to ensure that drug concentrations in vivo were consistent with those of propriety brands and previously published data. METHODS: TFV/FTC concentrations were measured by ultra-performance liquid chromatography ultraviolet detection. Evaluation of renal function and testing for HIV, hepatitis B virus (HBV) and hepatitis C virus (HCV) were also carried out, at baseline and every 3-6 months, with risk reduction advice. RESULTS: A total of 293 individuals presented having purchased PrEP on the internet: 85% were white, 84% were taking daily PrEP, and 16% were event-driven. Most were on generic TFV disoproxil fumarate (TDF)/FTC from Cipla Ltd. Median (range) TFV and FTC plasma concentrations were 104 (21-597) ng/mL and 140 (17-1876) ng/mL, respectively. All concentrations were above our established plasma TFV and FTC targets, based on previously published data. Renal function was normal in all evaluable individuals and no new cases of HIV, HBV or HCV infection were seen. CONCLUSIONS: In a population at high risk of HIV acquisition, who cannot yet access PrEP on the NHS, concentrations of TFV and FTC in generic formulations purchased over the internet were similar to (or slightly higher than) those measured in phase I studies with the original formulation from Gilead (Truvada™), which has demonstrated high levels of protection against HIV infection in previous PrEP clinical trials.


Subject(s)
Anti-HIV Agents/administration & dosage , Chemoprevention/methods , Disease Transmission, Infectious/prevention & control , Emtricitabine/administration & dosage , HIV Infections/prevention & control , Pre-Exposure Prophylaxis/methods , Tenofovir/administration & dosage , Adolescent , Adult , Aged , Anti-HIV Agents/adverse effects , Anti-HIV Agents/pharmacokinetics , Chromatography, Liquid , Emtricitabine/adverse effects , Emtricitabine/pharmacokinetics , Female , Humans , London , Male , Middle Aged , Plasma/chemistry , Tenofovir/adverse effects , Tenofovir/pharmacokinetics , Treatment Outcome , Young Adult
3.
Forensic Sci Int ; 281: 161-170, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29156218

ABSTRACT

Gunshot residues (GSR) are important physical evidence in firearm-related crimes. Recently developed non-toxic ammunition, however, requires a new methodology for its characterization. To overcome this drawback, the introduction of noncommercial luminescent markers in ammunition was proposed. These markers, synthesized and added to the gunpowder, presented as a versatile tool for GSR analysis, since they require UV radiation alone to visualize the luminescent GSR (LGSR). This has opened up new perspectives for understanding GSR behavior at a crime scene. This work aims to expand previous studies performed with the luminescent markers in forensic contexts, exploring four different important aspects related to GSR behavior. Using LGSR amount/dispersion and a series of blind tests with marked ammunition, we tried to (1) identify the shooter position; (2) estimate the shooting distance; (3) evaluate the influence of the pistol type on the LGSR distribution on the shooter's hands and guns; and (4) study the transference of LGSR by a chain of handshaking. For this purpose, a portable UV lamp (λ=254nm) and/or techniques such as video spectral comparator (VSC) and scanning electron microscopy with energy dispersive X-ray analysis (SEM/EDS) were used to visualize and analyze the residues. As a result, the observation of the LGSR enabled accurate determination of the shooter position and the firing distance without any chemicals. Besides, the LGSR were visualized on different kinds of pistols, regardless of firing mechanism. And finally, this study evidenced transference of residues from shaking hands with the shooter, which should be carefully considered when interpreting the results of a GSR analysis.

4.
Forensic Sci Int ; 275: 8-13, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28285091

ABSTRACT

This work describes the incorporation of luminescent taggants in cartridges of ammonium nitrate-fuel oil (ANFO) to allow easy identification and collection of post-blast residues. Metal-Organic Frameworks taggants proved to be appropriate for explosive marking when ANFO proportions were above 3.0wt.%. Lanthanide-based light emission enabled in situ retrieval of explosive residues as well as chemical identification, allowing the creation of a coding system using Energy Dispersive Spectroscopy (EDS). The proposed method will accelerate laboratory analysis and support forensic investigations, connecting evidence to suspects and/or to the explosive origin.

5.
Forensic Sci Int ; 244: 276-84, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25305530

ABSTRACT

Chemical evaluation of gunshot residues (GSR) produced by non-toxic lead-free ammunition (NTA) has been a challenge to forensic analyses. Our group developed some luminescent markers specific to the detection of GSR. Here, we evaluated the performance of selected markers in experiments that mimic forensic context and/or routines in which luminescent characteristics would be very useful. We evaluated the influence of markers' addition on the bullet's speed, the rate of shot failure (i.e., when the cartridge case is not fully ejected and/or a new ammunition is not automatically replaced in the gun chamber) as a function of marker percentage, the possibility of collecting luminescent gunshot residue (LGSR) in unconventional locations (e.g. the shooters' nostrils), the LGSR lifetime after hand washing, the transfer of LGSR to objects handled by the shooter, and the dispersion of LGSR at the crime scene and on simulated victims. It was observed that high amounts of marker (10 wt%) cause high rates of failure on pistols, as well as a substantial decrease in bullet speed. However, the use of 2 wt% of marker minimizes these effects and allows LGSR detection, collection and analysis. Moreover, in all conditions tested, markers showed high performance and provided important information for forensic analyses. For instance, the LGSR particles were found on the floor, ranging from 0 to 9.4 m away from the shooter, on the door panel and seats after a car shooting experiment, and were found easily on a pig leg used to simulate a victim. When a selective tagging was done, it was possible to obtain positive or negative correlation between the victim and shooter. Additionally LGSR possesses a fairly long lifetime (9 h) and good resistance to hand washing (up to 16 washes).


Subject(s)
Forensic Ballistics/methods , Luminescence , Wounds, Gunshot , Aluminum/analysis , Clothing , Coordination Complexes/analysis , Dicarboxylic Acids/analysis , Hand Disinfection , Humans , Pyridines/analysis , Skin/chemistry , Ultraviolet Rays , Zinc/analysis
6.
An. pediatr. (2003, Ed. impr.) ; 80(5): 299-303, mayo 2014. tab
Article in Spanish | IBECS | ID: ibc-122029

ABSTRACT

INTRODUCCIÓN: El citomegalovirus (CMV) es principal virus causante de infecciones congénitas y posnatales en la población pediátrica. El objetivo de este estudio es evaluar la utilidad de una PCR cuantitativa en tiempo real en el diagnóstico de estas infecciones utilizando la orina como única muestra. PACIENTES Y MÉTODOS: Se estudiaron todas aquellas muestras de orina de recién nacidos (< 7 días) con sospecha de infección congénita y las orinas de pacientes con sospecha de infección posnatal (orina al nacer negativa). Las orinas se han estudiado de forma simultánea mediante cultivo celular, PCR cualitativa (PCRc) y PCR cuantitativa en tiempo real (PCRq). RESULTADOS: Se han analizado 332 orinas (270 para descartar infección congénita y 62 infección posnatal). De las primeras 22, fueron positivas en la PCRq, 19 en la PCRc y 17 en el cultivo. Al comparar el cultivo con el resto de técnicas, la PCRq presentó una sensibilidad del 100%. Si se utiliza la PCRq como referencia, el cultivo presentó una sensibilidad del 77,2% y la PCRc del 86,3%. En los casos de infección posnatal, la PCRq detectó 16 positivas, la PCRc 12 y el cultivo celular 10 orinas como positivas. Las orinas presentaron unas cargas virales que oscilaban entre 2.178 y 116.641 copias/ml. CONCLUSIONES: La técnica de amplificación genómica PCRq en tiempo real se ha mostrado más sensible que las otras técnicas analizadas. Esta técnica debería ser considerada como de referencia (gold standard), dejando al cultivo celular como técnica secundaria. El bajo coste y la automatización de la PCRq permitirían realizar el cribado de infección por CMV a grandes poblaciones neonatales y posnatales


INTRODUCTION: Cytomegalovirus (CMV) is the main virus causing congenital and postnatal infections in the pediatric population. The aim of this study is to evaluate the usefulness of a quantitative real-time PCR in the diagnosis of these infections using urine as a single sample. PATIENTS AND METHODS: We studied all the urine samples of newborns (< 7 days) with suspected congenital infection, and urine of patients with suspected postnatal infection (urine negative at birth). Urines were simultaneously studied by cell culture, qualitative PCR (PCRc), and quantitative real-time PCR (PCRq). RESULTS: We analyzed 332 urine samples (270 to rule out congenital infection and 62 postnatal infections). Of the first, 22 were positive in the PCRq, 19 in the PCRc, and 17 in the culture. PCRq had a sensitivity of 100%, on comparing the culture with the rest of the techniques. Using the PCRq as a reference method, culture had a sensitivity of 77.2%, and PCRc 86.3%. In cases of postnatal infection, PCRq detected 16 positive urines, the PCRq 12, and the cell culture 10.The urines showed viral loads ranging from 2,178 to 116,641 copies/ml. CONCLUSIONS: The genomic amplification technique PCRq in real time was more sensitive than the other techniques evaluated. This technique should be considered as a reference (gold standard), leaving the cell culture as a second diagnostic level. The low cost and the automation of PCRq would enable the screening for CMV infection in large neonatal and postnatal populations


Subject(s)
Humans , Male , Female , Infant, Newborn , Polymerase Chain Reaction , Cytomegalovirus Infections/congenital , Nucleic Acid Amplification Techniques , Cytomegalovirus/isolation & purification , Urinalysis/methods , Sensitivity and Specificity
7.
An Pediatr (Barc) ; 80(5): 299-303, 2014 May.
Article in Spanish | MEDLINE | ID: mdl-24103236

ABSTRACT

INTRODUCTION: Cytomegalovirus (CMV) is the main virus causing congenital and postnatal infections in the pediatric population. The aim of this study is to evaluate the usefulness of a quantitative real-time PCR in the diagnosis of these infections using urine as a single sample. PATIENTS AND METHODS: We studied all the urine samples of newborns (< 7 days) with suspected congenital infection, and urine of patients with suspected postnatal infection (urine negative at birth). Urines were simultaneously studied by cell culture, qualitative PCR (PCRc), and quantitative real-time PCR (PCRq). RESULTS: We analyzed 332 urine samples (270 to rule out congenital infection and 62 postnatal infections). Of the first, 22 were positive in the PCRq, 19 in the PCRc, and 17 in the culture. PCRq had a sensitivity of 100%, on comparing the culture with the rest of the techniques. Using the PCRq as a reference method, culture had a sensitivity of 77.2%, and PCRc 86.3%. In cases of postnatal infection, PCRq detected 16 positive urines, the PCRq 12, and the cell culture 10. The urines showed viral loads ranging from 2,178 to 116,641 copies/ml. CONCLUSIONS: The genomic amplification technique PCRq in real time was more sensitive than the other techniques evaluated. This technique should be considered as a reference (gold standard), leaving the cell culture as a second diagnostic level. The low cost and the automation of PCRq would enable the screening for CMV infection in large neonatal and postnatal populations.


Subject(s)
Cytomegalovirus Infections/congenital , Cytomegalovirus Infections/diagnosis , Real-Time Polymerase Chain Reaction , Cells, Cultured , Cytomegalovirus Infections/urine , Humans , Infant, Newborn , Prospective Studies
8.
Epidemiol Infect ; 140(9): 1632-6, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22123531

ABSTRACT

Accurate data on West Nile virus (WNV) cases help guide public health education and control activities, and impact regional WNV blood product screening procedures. During an outbreak of WNV disease in Arizona, records from patients with meningitis or encephalitis were reviewed to determine the proportion tested for WNV. Of 60 patients identified with meningitis or encephalitis, 24 (40%) were tested for WNV. Only 12 (28%) of 43 patients aged <50 years were tested for WNV compared to 12 (71%) of 17 patients aged ≥50 years (P<0·01). Patients with clinical signs of weakness or paralysis, elevated CSF protein, admitted to an inpatient facility, or discharged to a rehabilitation facility were also more likely to have WNV testing performed. The lack of testing in younger age groups and in those with less severe disease probably resulted in substantial underestimates of WNV neuroinvasive disease burden.


Subject(s)
Disease Outbreaks , Encephalitis, Viral/virology , Meningitis, Viral/virology , Population Surveillance , West Nile Fever/epidemiology , West Nile Fever/virology , West Nile virus/isolation & purification , Adolescent , Adult , Aged , Aged, 80 and over , Arizona/epidemiology , Cities , Encephalitis, Viral/epidemiology , Female , Humans , Male , Meningitis, Viral/epidemiology , Middle Aged
9.
Epidemiol Infect ; 139(8): 1239-45, 2011 Aug.
Article in English | MEDLINE | ID: mdl-20875199

ABSTRACT

In 2005, over 600 clinically diagnosed typhoid fever cases occurred in South Africa, where an outbreak had been previously described in 1993. Case-control and molecular investigations, including Salmonella enterica serovar Typhi (S. Typhi) isolates from that area from 1993, 2005 and later, were undertaken. Controls were significantly older than cases (P=0·003), possibly due to immunity from previous infection, and a significantly larger proportion had attended a gathering (P=0·035). Exposure to commercial food outlets and person-to-person transmission was not significant. Pulsed-field gel electrophoresis and multi-locus tandem repeat analysis revealed common clusters of S. Typhi strains identified in 1993 and 2005 as well as in 2007 and 2009. This outbreak probably occurred in a non-immune population due to faecally contaminated water. S. Typhi strains appeared to be related to strains from 1993; failure to address unsafe water may lead to further outbreaks in the area if the current population immunity wanes or is lost.


Subject(s)
Disease Outbreaks , Salmonella typhi/classification , Salmonella typhi/genetics , Typhoid Fever/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Case-Control Studies , Child , Child, Preschool , Electrophoresis, Gel, Pulsed-Field , Female , Humans , Male , Middle Aged , Molecular Epidemiology , Molecular Typing , Salmonella typhi/isolation & purification , South Africa/epidemiology , Young Adult
10.
Eur J Pediatr Surg ; 21(2): 124-7, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21157693

ABSTRACT

BACKGROUND: We report on our experience of repair of congenital duodenal obstruction using a circumumbilical incision. The aim of this report is to describe how a Bianchi approach provides a safe and invisible alternative to transverse abdominal incision for the repair of duodenal atresia. METHODS: Between January 2005 and December 2009, we treated 13 cases with congenital duodenal obstruction using a circumumbilical incision (Group I) and 14 cases with this condition repaired using a standard transverse right upper abdominal incision (Group II). Surgical procedures included a diamond-shaped duodenoduodenostomy as originally described by Kimura and standard duodenal web excision. The circumumbilical incision utilized at our institution is a classic Bianchi procedure. The 2 groups were compared with regard to patient demographics, operative reports and postoperative outcomes. RESULTS: There were no differences in preoperative parameters such as gestational age, age at surgery, or body weight at operation between the 2 groups. The circumumbilical cohort and transverse incision cohort had similar rates of congenital anomalies (61.54% vs. 64.29%), Kimura diamond-shaped anastomosis (61.54% vs. 64.29%) with only a slight female predominance in Group I. The mean operating time in Group I was 65.0 min while mean duration of the operation in Group II was 64.64 min. The difference between groups was statistically not significant (p>0.05). The mean time to full enteral feeding for patients with an umbilical incision was significantly shorter (p<0.0001) compared to patients with a standard incision (6.92 days vs. 11.86 days). Mean postoperative hospital stay was longer for patients in Group II (19.71 days vs. 12.38 days; p<0.0001). The postoperative course was uneventful for all patients. There were no intra- or postoperative complications. CONCLUSION: We report on a first series comparing umbilical and transverse right upper abdominal incision for the treatment of congenital duodenal obstruction. Our results suggest that an umbilical incision offers all the benefits of a minimal access approach, including earlier feeding and shorter times to discharge. We consider our approach an intermediate step, with laparoscopy likely to become the "gold standard" for the treatment of congenital duodenal obstruction.


Subject(s)
Digestive System Surgical Procedures/methods , Duodenal Obstruction/surgery , Duodenum/surgery , Anastomosis, Surgical/methods , Duodenal Obstruction/congenital , Duodenal Obstruction/diagnosis , Duodenum/abnormalities , Female , Follow-Up Studies , Humans , Infant, Newborn , Male , Retrospective Studies , Treatment Outcome , Umbilicus/surgery
12.
Nuklearmedizin ; 47(4): 153-6, 2008.
Article in English | MEDLINE | ID: mdl-18690374

ABSTRACT

AIM: This study was performed to analyse the impact of the choice of antithyroid drugs (ATD) on the outcome of ablative radioiodine therapy (RIT) in patients with Graves' disease. PATIENTS, MATERIAL, METHODS: A total of 571 consecutive patients were observed for 12 months after RIT between July 2001 and June 2004. Inclusion criteria were the confirmed diagnosis of Graves' disease, compensation of hyperthyroidism and withdrawal of ATD two days before preliminary radioiodine-testing and RIT. The intended dose of 250 Gy was calculated from the results of the radioiodine test and the therapeutically achieved dose was measured by serial uptake measurements. The end-point measure was thyroid function 12 months after RIT; success was defined as elimination of hyperthyroidism. The pretreatment ATD was retrospectively correlated with the results achieved. RESULTS: Relief from hyperthyroidism was achieved in 96% of patients. 472 patients were treated with carbimazole or methimazole (CMI) and 61 with propylthiouracil (PTU). 38 patients had no thyrostatic drugs (ND) prior to RIT. The success rate was equal in all groups (CMI 451/472; PTU 61/61; ND 37/38; p = 0.22). CONCLUSION: Thyrostatic treatment with PTU achieves excellent results in ablative RIT, using an accurate dosimetric approach with an achieved post-therapeutic dose of more than 200 Gy.


Subject(s)
Graves Disease/radiotherapy , Iodine Radioisotopes/therapeutic use , Adolescent , Adult , Aged , Aged, 80 and over , Antithyroid Agents/therapeutic use , Carbimazole/therapeutic use , Combined Modality Therapy , Dose-Response Relationship, Radiation , Female , Graves Disease/drug therapy , Humans , Hyperthyroidism/epidemiology , Male , Methimazole/therapeutic use , Middle Aged , Propylthiouracil/therapeutic use , Recurrence , Retrospective Studies , Treatment Outcome
13.
Nuklearmedizin ; 47(1): 13-7, 2008.
Article in English | MEDLINE | ID: mdl-18278207

ABSTRACT

AIM: This study was performed to determine the results of ablative radioiodine therapy (RIT) when the achieved dose in the thyroid was above 200 Gy and to characterize predictive factors for treatment outcome. PATIENTS, METHODS: A total of 571 consecutive patients were observed for 12 months between July 2001 and June 2004. Inclusion criteria were a confirmed diagnosis Graves' disease, compensation of hyperthyroidism and withdrawal of antithyroid drugs two days before preliminary radioiodine-testing and RIT. The intended dose was 250 Gy and the therapeutically achieved dose was calculated from serial uptake measurements. The end-point measure was thyroid function 12 months after RIT; success was defined as elimination of hyperthyroidism. The relation between success rate and the achieved dose, thyroid volume, age and sex of patients, TSH- and TRAb-values and presence of ophthalmopathy was analysed. RESULTS: Relief from hyperthyroidism was achieved in 96% of patients who received more than 200 Gy, even for thyroid volumes >40 ml. The success of ablative RIT was not influenced by age or sex of patients, or by TSH- or TRAb values or concomitant ophthalmopathy. The mean achieved dose in the thyroid was 298 Gy with a standard deviation of 74.6 Gy. CONCLUSION: To achieve a dose of over 200 Gy with the above standard deviation, we recommend calculating an intended dose of 250 Gy and using a dosimetric approach with early and late uptake values in the radioiodine test, to allow early therapeutic intervention should the posttherapeutic thyroid dose fall unexpectedly below 200 Gy.


Subject(s)
Graves Disease/radiotherapy , Iodine Radioisotopes/therapeutic use , Radiotherapy/methods , Adult , Humans , Middle Aged , Organ Size , Radioisotopes/therapeutic use , Radiotherapy Dosage , Retrospective Studies , Thyroid Gland/anatomy & histology , Thyroid Gland/radiation effects , Thyrotropin/blood
14.
AJNR Am J Neuroradiol ; 29(2): 388-91, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17974608

ABSTRACT

BACKGROUND AND PURPOSE: The evidence for traumatic brain injury in amateur boxers is controversial. Hypothetically, sudden acceleration of the head due to the impact of the blow during the boxing fight might result in diffuse axonal injury or contusion. We wanted to determine whether cerebral microhemorrhages occur more often in amateur boxers than in nonboxers. MATERIALS AND METHODS: In 42 male, classical amateur boxers and in 37 healthy, nonboxing male volunteers we performed cranial MR imaging at 3T. The study protocol included a transverse dual spin-echo MR imaging sequence, a 3D sagittal magnetization-prepared rapid acquisition of gradient echo sequence, a coronal T2*-weighted sequence, and an axial time-of-flight MR angiography sequence. MR imaging data were made anonymous before 2 neuroradiologists independently evaluated the images. In addition, the following risk factors were assessed: total numbers of fights and knockouts, weight division, and duration of boxing. We compared the group proportions of microhemorrhages with Fisher test of exact probability. RESULTS: There was a statistically higher prevalence of cerebral microhemorrhages in the group of boxers (3 of 42; 7.1%) than in nonboxing persons (0 of 37; 0%). This difference was not statistically significant, however (P = .2479; Fisher exact test). CONCLUSION: Although we detected more microhemorrhages in amateur boxers than in nonboxing persons, this difference did not prove to be significant.


Subject(s)
Boxing/injuries , Boxing/statistics & numerical data , Brain Injuries/epidemiology , Brain Injuries/pathology , Cerebral Hemorrhage/epidemiology , Cerebral Hemorrhage/pathology , Risk Assessment/methods , Adolescent , Adult , Aged , Comorbidity , Germany/epidemiology , Humans , Magnetic Resonance Imaging/statistics & numerical data , Male , Microcirculation/pathology , Middle Aged , Prevalence , Risk Factors
15.
Acta Crystallogr Sect F Struct Biol Cryst Commun ; 63(Pt 12): 1003-7, 2007 Dec 01.
Article in English | MEDLINE | ID: mdl-18084079

ABSTRACT

The sodA gene of Bacillus subtilis was expressed in Escherichia coli, purified and crystallized. The crystal structure of MnSOD was solved by molecular replacement with four dimers per asymmetric unit and refined to an R factor of 21.1% at 1.8 A resolution. The dimer structure is very similar to that of the related enzyme from B. anthracis. Larger structural differences were observed with the human MnSOD, which has one less helix in the helical domain and a longer loop between two beta-strands and also showed differences in three amino acids at the intersubunit interface in the dimer compared with the two bacterial MnSODs. These structural differences can be exploited in the design of drugs that selectively target the Bacillus enzymes.


Subject(s)
Bacillus subtilis/enzymology , Superoxide Dismutase/chemistry , Superoxide Dismutase/metabolism , Amino Acid Sequence , Bacillus subtilis/genetics , Binding Sites , Cloning, Molecular , Crystallography, X-Ray , Humans , Models, Molecular , Molecular Sequence Data , Protein Structure, Quaternary , Protein Structure, Tertiary , Protein Subunits/chemistry , Protein Subunits/genetics , Protein Subunits/metabolism , Structural Homology, Protein , Superoxide Dismutase/genetics , Superoxide Dismutase/isolation & purification
18.
Science ; 317(5836): 345-7, 2007 Jul 20.
Article in English | MEDLINE | ID: mdl-17641194

ABSTRACT

Eucrites are a group of meteorites that represent the first planetary igneous activity following metal-silicate differentiation on an early planetesimal, similar to Asteroid 4 Vesta, and, thus, help date geophysical processes occurring on such bodies in the early solar system. Using the short-lived radionuclide (182)Hf as a relative chronometer, we demonstrate that eucrite zircon crystallized quickly within 6.8 million years of metal-silicate differentiation. This implies that mantle differentiation on the eucrite parent body occurred during a period when internal heat from the decay of (26)Al and (60)Fe was still available. Later metamorphism of eucrites took place at least 8.9 million years after the zircons crystallized and was likely caused by heating from impacts, or by burial under hot material excavated by impacts, rather than from lava flows. Thus, the timing of eucrite formation and of mantle differentiation is constrained.

19.
Food Chem Toxicol ; 45(9): 1709-18, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17459552

ABSTRACT

UNLABELLED: Effects of common anaesthetics such as ether, methoxyflurane, isoflurane, carbon dioxide (at 100%, 80% or 60% admixed with O(2)) on toxicity and clinical pathology parameters in rats were investigated. Ether, methoxyflurane and 100% CO(2) induced toxicity in some animals. Erythrocyte, haemoglobin and haematocrit were reduced in females by 100% CO(2), methoxyflurane and isoflurane. Glucose was increased by 60% CO(2), 80% CO(2), ether, isoflurane and methoxyflurane in males. Chloride was reduced by isoflurane and all CO(2) concentrations in females. Serum proteins were reduced by isoflurane and methoxyflurane. Sodium, inorganic phosphate, calcium and magnesium were reduced by methoxyflurane and isoflurane, but increased by all CO(2) concentrations. Potassium was reduced by ether, methoxyflurane or isoflurane. Triiodothyronine and thyroxine were reduced by all anaesthetics. Prolactin was reduced by methoxyflurane, but raised by ether and isoflurane. Erythrocyte cholinesterase (E-ChE) activity is markedly reduced (20-40%) after anaesthesia with all CO(2) concentrations in both sexes. E-ChE was unaffected by ether, methoxyflurane, or isoflurane. Serum and brain cholinesterase activities were not affected. E-ChE inhibition correlated with decreased blood pH, suggesting that this was caused by acidosis. This is of practical relevance in the risk assessment of cholinesterase inhibitors. CONCLUSIONS: Clinical pathology data were affected by all anaesthetics. CO(2)/O(2) (80%/20%) and isoflurane are the most suitable anaesthetics. If E-ChE activity is to be determined, isoflurane is the anaesthetic of choice.


Subject(s)
Anesthetics, Inhalation/pharmacology , Cholinesterases/metabolism , Erythrocytes/enzymology , Rats/physiology , Animals , Blood Chemical Analysis , Carbon Dioxide/pharmacology , Cholinesterases/drug effects , Dose-Response Relationship, Drug , Ether/pharmacology , Female , Hematologic Tests , Isoflurane/pharmacology , Male , Methoxyflurane/pharmacology , Random Allocation , Rats/blood
20.
J Dairy Sci ; 90(4): 1929-42, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17369233

ABSTRACT

The objective of this study was to investigate the effects of varying dietary forage particle size on chewing activity, ruminal mat characteristics, passage, and in situ ruminal and total tract digestion in dairy cows at a low- and high-concentrate inclusion. The experiment was designed as a 4 x 4 Latin square with a 2 x 2 factorial arrangement of treatments. Four ruminally cannulated late-lactating dairy cows were restrictively fed (17 kg of dry matter/d), in four 23-d periods, 1 of 4 different diets varying in the theoretical particle size (6 and 30 mm) of hay (56.6% NDF of dry matter) and in the levels (approximately 20 and 60%, dry matter basis) of a cereal-based concentrate. Ingredients of the ration were offered separately to the cows; dietary hay and low-level concentrate were offered twice daily at 0800 and 1600 h, whereas concentrate of the high-level treatment was offered in 4 meals a day at 0800, 1200, 1600, and 1900 h. This study showed that altering the forage particle size from 6 to 30 mm in a low-concentrate diet significantly increased the rumination time and ruminal mat consistency without affecting ruminal fermentation and passage. Further, particle breakdown and proportion of mat in the rumen increased, and in situ hay dry matter degradability improved, which in turn indicated a higher capacity of ruminal digesta to degrade fiber. On the other hand, increasing the forage particle size in a diet containing a high amount of concentrate increased the proportion of dry matter retained on a 1.18-mm screen from 37.5 to 42.0% and extended the rumination time by 100 min/d, as well as increasing the ruminal mat consistency. However, ruminal particle breakdown, short-term ruminal pH, fibrolytic capacity of the digesta, and proportion of mat in the rumen decreased. This was also reflected in a higher bailable liquid pool, increased fractional passage rate of solid digesta from the reticulorumen, and increased retention time in the hindgut, which in turn indicated a shift of fiber digestion from the rumen to the lower digestive tract. This study showed that the response of chewing or ruminating activity alone seemed to be insufficient to assess the dietary physical effectiveness or fiber adequacy in limit-fed dairy cows when high-concentrate diets were fed separately. Based on the results of this study, we concluded that inclusion of coarsely chopped hay in the high-concentrate diet did not appear to further improve rumen conditions and digestion when the rations were formulated to exceed the fiber requirements in limit-fed dairy cows.


Subject(s)
Cattle/physiology , Diet/veterinary , Mastication/physiology , Particle Size , Rumen/metabolism , Animal Feed/analysis , Animals , Body Weight/physiology , Digestion/physiology , Eating/physiology , Fatty Acids, Volatile/analysis , Female , Fermentation/physiology , Gastrointestinal Contents/chemistry , Hydrogen-Ion Concentration , Rumen/chemistry , Time Factors
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