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1.
Forensic Sci Int ; 319: 110643, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33321384

RESUMO

Latent fingermarks are routinely visualised by subjecting them to one or more CSI/crime lab processes to maximise the recovery of ridge flow and minutiae permitting an identification. In the last decade mass spectrometric imaging (MSI) techniques have been applied to fingermarks to provide information about a suspect and/or on the circumstances of the crime as well as yielding additional images of the ridge pattern. In some cases, these techniques have shown the ability to provide further ridge detail, "filling in the gaps" of the developed mark. Matrix Assisted Laser Desorption Ionisation Mass Spectrometry Imaging (MALDI MSI) is presently the most advanced of the so-called 'surface analysis' techniques, in terms of compatibility with a number of fingermark enhancement processes and implementation in operational casework. However, for the use of this technique in major crimes to become widespread, compatibility with sequential processing must be demonstrated. This short study has assessed compatibility with a number fingermark processing sequences applied to natural marks on the adhesive side of brown (parcel) and clear tapes. Within the study undertaken, the results confirm the possibility to use MALDI MSI in sequence with multiple processes offering in some instances, complementary ridge detail with respect to that recovered from marks developed by conventional sequence processing.

2.
Sci Rep ; 8(1): 8765, 2018 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-29884869

RESUMO

In September 2016, the UK adopted a new Bank of England (BoE) £5 polymer banknote, followed by the £10 polymer banknote in September 2017. They are designed to be cleaner, stronger and have increased counterfeit resilience; however, fingermark development can be problematic from the polymer material as various security features and coloured/textured areas have been found to alter the effectiveness of conventional fingermark enhancement techniques (FETs). As fingermarks are one of the most widely used forms of identification in forensic cases, it is important that maximum ridge detail be obtained in order to allow for comparison. This research explores the use of matrix-assisted laser desorption/ionisation mass spectrometry (MALDI-MS) profiling and imaging for the analysis of fingermarks deposited on polymer banknotes. The proposed methodology was able to obtain both physical and chemical information from fingermarks deposited in a range of scenarios including; different note areas, depletion series, aged samples and following conventional FETs. The analysis of forensically important molecular targets within these fingermarks was also explored, focussing specifically on cocaine. The ability of MALDI-MS to provide ridge detail and chemical information highlights the forensic applicability of this technique and potential for the analysis of fingermarks deposited onto this problematic surface.

3.
Analyst ; 142(14): 2518-2546, 2017 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-28639631

RESUMO

Since 2009, when Matrix Assisted Laser Desorption Ionisation Mass Spectrometry Imaging (MALDI MSI) was firstly reported for the molecular mapping of latent fingermarks, the range of information and operational capabilities have steadily increased. Pioneering work from our Fingermark Research Group exploited different modalities, including Profiling (MALDI MSP), tandem mass spectrometry (MS/MS) and Ion Mobility MS/MS; a number of methodologies were also developed to conquer a main challenge, namely profiling the suspect and their actions prior to or whilst committing the crime. Suspect profiling here is no longer based on behavioural science but complements this discipline and the investigations by detecting and visualising the molecular make-up of fingermarks onto the identifying ridges. This forensic opportunity provides the link between the biometric information (ridge detail) and the corpus delicti or intelligence on the circumstances of the crime. In 2013, a review was published covering the research work and developments of four years supported by the Home Office, UK, and the local regional Police with some insights (and comparison) into similar research being reported employing other mass spectrometric techniques. The present review is an extensive update on the MALDI MS based methods' achievements, limitations and work in progress in fingermark analysis; it also offers an outlook on further necessary research into this subject. The main highlights are the increased number of possible information retrievable around a suspect and the more extended compatibility of this technology. The latter has allowed MALDI MS based methods to integrate well with current forensic fingerprinting, leading to the investigation of real police casework.

4.
Analyst ; 142(9): 1581-1590, 2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28387396

RESUMO

In the study presented here, four examples of crime scene fingermarks analysed by Matrix Assisted Laser Desorption Ionisation Mass Spectrometry Imaging (MALDI MSI), in collaboration with the local Police Force, are reported. These marks are associated to high profile crimes such as drug dealing, murder and harassment. Following the application of forensic enhancement techniques by the CSI or the crime lab, one of the marks could be directly analysed on the surface of deposition and the others were analysed as primary lifts. In one case, no physical or molecular information was obtained whereas in two cases both ridge detail (albeit not useful for identification purposes) and molecular information could be retrieved. In one case, the intelligence gathered around the suspect's state of mind is, to date the most accomplished demonstration of the benefits and the operational feasibility MALDI MS based methods. These four casework examples are to be considered a first insight into the limitations, benefits and feasibility of MALDI MS based methods in the field; due to the extreme variability in the state of the mark, comprehensive evaluation of these aspects can only be undertaken upon the analysis of a large number of crime scene marks. However, this work does represent a significant advancement, compared to previous published work, as it demonstrates operational feasibility, with different levels of success, despite uncontrollable, unknown and unaccountable environmental and donor variability.

5.
Sci Rep ; 5: 11716, 2015 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-26118853

RESUMO

Despite the proven capabilities of Matrix Assisted Laser Desorption Ionisation Mass Spectrometry (MALDI MS) in laboratory settings, research is still needed to integrate this technique into current forensic fingerprinting practice. Optimised protocols enabling the compatible application of MALDI to developed fingermarks will allow additional intelligence to be gathered around a suspect's lifestyle and activities prior to the deposition of their fingermarks while committing a crime. The detection and mapping of illicit drugs and metabolites in latent fingermarks would provide intelligence that is beneficial for both police investigations and court cases. This study investigated MALDI MS detection and mapping capabilities for a large range of drugs of abuse and their metabolites in fingermarks; the detection and mapping of a mixture of these drugs in marks, with and without prior development with cyanoacrylate fuming or Vacuum Metal Deposition, was also examined. Our findings indicate the versatility of MALDI technology and its ability to retrieve chemical intelligence either by detecting the compounds investigated or by using their ion signals to reconstruct 2D maps of fingermark ridge details.


Assuntos
Dermatoglifia , Ciências Forenses/métodos , Drogas Ilícitas/metabolismo , Metaboloma , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Humanos
6.
Sci Justice ; 54(2): 110-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24630320

RESUMO

The determination of the presence of blood in fingermarks constitutes important intelligence in a criminal investigation as it helps to reconstruct the events that have taken place at a scene of crime. Various methodologies have been reported and are currently employed for the detection of the presence of blood including optical, spectroscopic and chemical development approaches. However, most methods only give an indication that blood may be present and, therefore, these methods are described as presumptive tests. Here we show the use of Matrix-Assisted Laser Desorption Ionisation Mass Spectrometry Profiling and Imaging (MALDI MSP and MALDI MSI) for the determination of the presence of blood in fingermarks by specifically detecting the molecules of haem and haemoglobin through their mass-to-charge ratios. Furthermore, preliminary experiments are shown which demonstrate that this technology is compatible with other methods currently employed for enhancing fingermarks in blood (or contaminated by blood). The application of the developed protocols to a crime scene blood trace, demonstrates the feasibility of using this technology in routine casework. These findings open up a new line of research for the development of robust MALDI MSP and MALDI MSI protocols for the detection and chemical imaging of bloodied marks.


Assuntos
Análise Química do Sangue , Manchas de Sangue , Heme/análise , Hemoglobinas/análise , Medicina Legal , Heme/química , Hemoglobinas/química , Humanos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Coloração e Rotulagem
7.
Health Promot Pract ; 15(1 Suppl): 64S-70S, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24578368

RESUMO

This article describes a public health leadership certificate curriculum developed by the Commonwealth Public Health Training Center for employees in public health and medical trainees in primary care to share didactic and experiential learning. As part of the program, trainees are involved in improving the health of their communities and thus gain a blended perspective on the effectiveness of interprofessional teams in improving population health. The certificate curriculum includes eight one-credit-hour didactic courses offered through an MPH program and a two-credit-hour, community-based participatory research project conducted by teams of trainees under the mentorship of health district directors. Fiscal sustainability is achieved by sharing didactic courses with MPH degree students, thereby enabling trainees to take advantage of a reduced, continuing education tuition rate. Public health employee and primary care trainees jointly learn knowledge and skills required for community health improvement in interprofessional teams and gain an integrated perspective through opportunities to question assumptions and broaden disciplinary approaches. At the same time, the required community projects have benefited public health in Virginia.


Assuntos
Certificação , Currículo , Educação Profissional em Saúde Pública , Comunicação Interdisciplinar , Liderança , Atenção Primária à Saúde , Educação Continuada , Feminino , Humanos , Masculino , Estados Unidos
8.
Sci Total Environ ; 470-471: 934-44, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24239814

RESUMO

The role that deficient institutional relationships have played in aggravating drinking water incidents over the last 30 years has been identified in several inquiries of high profile drinking water safety events, peer-reviewed articles and media reports. These indicate that collaboration between water utilities and public health agencies (PHAs) during normal operations, and in emergencies, needs improvement. Here, critical elements of these interagency collaborations, that can be integrated within the corporate risk management structures of water utilities and PHAs alike, were identified using a grounded theory approach and 51 semi-structured interviews with utility and PHA staff. Core determinants of effective interagency relationships are discussed. Intentionally maintained functional relationships represent a key ingredient in assuring the delivery of safe, high quality drinking water.


Assuntos
Comportamento Cooperativo , Água Potável/normas , Relações Interinstitucionais , Poluição da Água/legislação & jurisprudência , Qualidade da Água/normas , Abastecimento de Água/normas , Água Potável/química , Saúde Pública , Poluição da Água/prevenção & controle , Poluição da Água/estatística & dados numéricos , Abastecimento de Água/estatística & dados numéricos
9.
Analyst ; 138(15): 4215-28, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23658933

RESUMO

After over a century, fingerprints are still one of the most powerful means of biometric identification. The conventional forensic workflow for suspect identification consists of (i) recovering latent marks from crime scenes using the appropriate enhancement technique and (ii) obtaining an image of the mark to compare either against known suspect prints and/or to search in a Fingerprint Database. The suspect is identified through matching the ridge pattern and local characteristics of the ridge pattern (minutiae). However successful, there are a number of scenarios in which this process may fail; they include the recovery of partial, distorted or smudged marks, poor quality of the image resulting from inadequacy of the enhancement technique applied, extensive scarring/abrasion of the fingertips or absence of suspect's fingerprint records in the database. In all of these instances it would be very desirable to have a technology able to provide additional information from a fingermark exploiting its endogenous and exogenous chemical content. This opportunity could potentially provide new investigative leads, especially when the fingermark comparison and match process fails. We have demonstrated that Matrix Assisted Laser Desorption Ionisation Mass Spectrometry and Mass Spectrometry Imaging (MALDI MSI) can provide multiple images of the same fingermark in one analysis simultaneous with additional intelligence. Here, a review on the pioneering use and development of MALDI MSI for the analysis of latent fingermarks is presented along with the latest achievements on the forensic intelligence retrievable.


Assuntos
Dermatoglifia , Ciências Forenses/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Ciências Forenses/tendências , Humanos , Preparações Farmacêuticas/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/tendências
10.
Anal Chem ; 85(10): 5240-8, 2013 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-23621442

RESUMO

Curcumin, 1,7-bis-(4-hydroxy-3-methoxy-phenyl)-hepta-1,6-diene-3,5-dione, is a polyphenolic compound naturally present in the Curcuma longa plant, also known as tumeric. Used primarily as a coloring agent and additive in food, curcumin has also long been used for its therapeutic properties in a number of medical scenarios. Here, we report on an entirely novel use of curcumin; its extended structure of conjugated double bonds suggested the potential of this compound to be a good matrix assisted laser desorption ionization mass spectrometry (MALDI MS) matrix candidate. In the quest for novel and more efficient MALDI MS matrices, curcumin is revealed to be a versatile and multipurpose matrix. It has been applied successfully for the analysis of pharmaceuticals and drugs, for imaging lipids in skin and lung tissues, and for the analysis of a number of compound classes in fingermarks. In each case, the use of curcumin is shown to promote analyte ionization very efficiently as well as provide excellent mass spectral image quality.


Assuntos
Curcumina/química , Imagem Molecular/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Dermatoglifia , Pulmão/citologia , Ratos , Pele/citologia
11.
Adv Biol Regul ; 53(1): 87-96, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23266087

RESUMO

Receptor tyrosine kinases (RTKs) function through protein kinase entities located in the intracellular domain of each protomer. Following activation by ligand binding, they selectively form phosphotyrosine residues by autocatalytic modification. Some of these sites are involved in maintaining the active conformation of the kinase, while others become docking sites for various adaptor/effector/scaffold proteins, which, after complexing with the receptor, then initiate further responses through cascades of post-translational modifications and the generation of lipid second messengers. Although there is substantial overlap in the pathways and activities stimulated by this superfamily, the molecular features of the endodomains of the sub-families and the moieties that they interact with to perpetrate their signals are surprisingly distinct, which may play a significant role in the regulation and responses of the individual RTK types. Some use large scaffold proteins as the basis for most, if not all, of their signal-generating interactions, while others have numerous receptor endodomain phosphotyrosine sites that are quite overlapping in specificity. The members of the Trk family of receptors each have several tyrosine residues that are phosphorylated following stimulation, including those in the kinase activation loop, but there are only two established sites (Y490 and Y785 on TrkA) that are known to be directly involved in signal propagation. Taking advantage of this limited repertoire of docking sites, we have applied phosphoproteomic methods to dissect the signaling responses of both the native protein and derivatives that have had these two sites modified. Interestingly, a clear subset that was not dependent on either docking site was identified. A comparison with a similar set of data for EGFR indicates a considerable degree of similarity in the downstream signaling profile between these two RTKs.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Fosfoproteínas/metabolismo , Fosfotirosina/metabolismo , Processamento de Proteína Pós-Traducional , Receptor trkA/metabolismo , Transdução de Sinais , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Regulação da Expressão Gênica , Humanos , Ligantes , Fosfoproteínas/genética , Fosforilação , Fosfotirosina/genética , Regiões Promotoras Genéticas , Ligação Proteica , Proteoma , Receptor trkA/genética
12.
Forensic Sci Int ; 222(1-3): 318-26, 2012 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-22889915

RESUMO

Latent fingermarks are impressions of the skin ridge pattern that are transferred by the accidental contact of fingertips with a deposition surface. The ability to enhance, lift and produce an image of a latent fingermark, for comparison and suspect match against a central fingerprint database, provides forensic investigators with what is still considered one of the most powerful means of biometric identification to date. Identification relies on the recovery, visualisation, extraction and comparison of local characteristics of the ridge pattern (minutiae) that are unique to individuals. Therefore, both for manual inspection of the minutiae and using automated ridge extraction algorithms, the clearer the ridge details, the more reliable and successful the match. Overlapping fingermarks pose a remarkable challenge in this context and are often encountered when developing marks from crime scenes. Here we propose the use of Matrix Assisted Laser Desorption Ionisation Mass Spectrometry Imaging (MALDI MSI) to separate overlapping fingermarks using ion signals that are characteristic of each fingermark and that may be endogenous or exogenous in nature. In this work we show that the methodology works in a number of different scenarios both using manual inspection of the spectrum profile or a much quicker multivariate statistical analysis.


Assuntos
Dermatoglifia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Cafeína/análise , Estimulantes do Sistema Nervoso Central/análise , Humanos , Análise Multivariada , Sebo/química , Suor/química
13.
Anal Chem ; 83(14): 5585-91, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21667965

RESUMO

Matrix deposition is a crucial aspect for successful matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI MSI) analysis. The search for more efficient protocols over the years has resulted in the devising of "dry matrix methods" in which the matrix is solely or preliminarily deposited as powder and acts in most cases as a seeding agent. Although not fully embraced by the MALDI MSI community, these methods have proven to be more efficient in terms of ion intensity, ion abundance, and ion images in the experimental circumstances they were employed. Here we report a novel two-step matrix application method, that we have named the "dry-wet" method, where the matrix is dusted onto the sample followed by solvent spray using a robotic device. The new method has been successfully applied to the detection and mapping of several analyte classes within latent fingermarks. Dusting the matrix generated the added advantage of enhancing the latent fingermarks which are invisible. This allows not only for an optical image to be taken of the fingermark in situ but also bridges the gap in the application of MALDI MSI technology in this field; with the use of the methodology reported, fingermark enhancement, recovery, and analysis from different surfaces is now compatible with subsequent MALDI MSI analysis thus allowing visual and chemical information to be obtained simultaneously.

14.
Ann N Y Acad Sci ; 1077: 63-74, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17124115

RESUMO

High-temperature measurement and study of reactive materials can be difficult with conventional processing methods because contamination from the measuring apparatus and container walls can adversely affect measurements. Containerless processing techniques can be employed to isolate samples from their environment, reducing contamination. Benefits of containerless processing include reduction in heterogeneous nucleation sites, which in turn delays the onset of solidification and allows the study of meta-stable undercooled phases. However, property measurements must use noncontact methods as well. Fortunately, several optical-based methods have been developed and successfully employed to measure thermophysical properties, including surface tension, viscosity, density, and thermal expansion. Combining these techniques with the electrostatic levitator (ESL) located at the NASA Marshall Space Flight Center (MSFC) has resulted in an excellent facility to perform containerless material studies which support microgravity flight projects. Currently, studies of the thermophysical properties of liquid quasi-crystal forming and related alloys ranging from superheated to deeply undercooled states are being done with this facility in support of the NASA-funded flight project Quasi-crystalline Undercooled Alloys for Space Investigation (QUASI). While the primary purpose of these measurements is to support planned flight experiments, they are also a desirable resource for future manufacturing considerations and for fundamental insight in the physics of icosahedral ordering in liquids and solids. Presented here is an overview of the contactless measuring methods for surface tension, viscosity, density, and thermal expansion applied to Zr54Ti8Cu20Al10Ni8, for the superheated and meta-stable undercooled liquid phases, in support of QUASI.

15.
J Am Acad Dermatol ; 55(1): 23-31, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16781288

RESUMO

BACKGROUND: We evaluated military personnel who developed dermatologic reactions suggestive of generalized vaccinia (GV) after smallpox vaccination. METHODS: We conducted surveillance and retrospective analysis of cases from the Vaccine Adverse Event Reporting System (a passive reporting system managed by the Centers for Disease Control and Prevention), and the military's preventive medicine channels, vaccine healthcare centers, clinical laboratory network, dermatology clinics, and pathology departments from December 2002 to December 2004. RESULTS: Of 74 cases investigated in 753,226 vaccinations, 50 (67.6%) met the case definition of possible GV (rate 66/million), 95% confidence interval (49-88/million), consistent with historically reported rates. Cases of possible GV occurred more frequently in primary vaccinees (81/million) than in those revaccinated (32/million) (relative risk 2.6, 95% confidence interval 1.2-5.9, P = .013). None met the case definition of probable or confirmed GV, including 15 with virologically negative laboratory evaluations (eg, culture, skin biopsy, or polymerase chain reaction). LIMITATIONS: The methods of case collection and retrospective nature of this study are its limitations. The clinical diagnosis of possible GV was made on the basis of the authors' interpretation of clinical notes and adverse events submitted by more than 100 different providers. Only 15 of the 74 cases of possible GV had laboratory attempts for virological confirmation. CONCLUSION: GV is still a rarely reported complication of smallpox vaccination. True GV, strictly defined, may be even less common than previously reported. We named one self-limited dermatologic manifestation confused with GV "postvaccinial nonviral pustulosis." Properly screened individuals considering smallpox vaccination may be assured most exanthemata after vaccination are benign.


Assuntos
Militares , Vacina Antivariólica/efeitos adversos , Vacínia/epidemiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População , Estudos Retrospectivos , Estados Unidos
16.
Mol Cell Proteomics ; 3(5): 429-40, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-14752058

RESUMO

Protein sulfonation on serine and threonine residues is described for the first time. This post-translational modification is shown to occur in proteins isolated from organisms representing a broad span of eukaryote evolution, including the invertebrate mollusk Lymnaea stagnalis, the unicellular malaria parasite Plasmodium falciparum, and humans. Detection and structural characterization of this novel post-translational modification was carried out using liquid chromatography coupled to electrospray tandem mass spectrometry on proteins including a neuronal intermediate filament and a myosin light chain from the snail, a cathepsin-C-like enzyme from the parasite, and the cytoplasmic domain of the human orphan receptor tyrosine kinase Ror-2. These findings suggest that sulfonation of serine and threonine may be involved in multiple functions including protein assembly and signal transduction.


Assuntos
Cadeias Leves de Miosina/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia , Proteínas de Protozoários/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Cromatografia Líquida , Clonagem Molecular , Humanos , Lymnaea/metabolismo , Espectrometria de Massas , Peptídeos/metabolismo , Plasmodium falciparum/metabolismo , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase , Serina/metabolismo , Treonina/metabolismo
17.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 3342-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-17270998

RESUMO

On-demand" information has been chosen by clinicians as one of their preferred modes of interaction with computers when in need of information about evidence-based practices. However, most of the clinicians' information needs remain unmet, especially due to a lack of easy access to resources that are able to satisfy these needs in a timely manner. We present three scenarios indicating opportunities for a clinical information system to present interdisciplinary standards at the point-of-care. In each scenario, we highlight the importance of context of use and the opportunities offered by the clinical workflow for providing access to relevant "on-demand" information. We also present an XML model for structuring non-physician interdisciplinary standards, in an effort to fulfill the requirements exposed by the three scenarios.

18.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 3350-3, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-17271000

RESUMO

As part of an enterprise effort to develop new clinical information systems at Intermountain Health Care, we are developing a Knowledge Authoring Tool that facilitates the development of medical knowledge. At present, users of the application can compose order sets and other clinical knowledge documents based upon XML schemas. The flexible nature of the application allows for the authoring of new types of documents once an XML schema and accompanying web form have been developed and stored in a shared repository. The need for a knowledge acquisition tool stems largely from the desire for medical practitioners to be able to write their own content for clinical use. We hypothesize that knowledge content for clinical use can be successfully implemented around XML-based document frameworks containing structured and coded knowledge.

19.
East Afr Med J ; 80(5): 253-9, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-16167741

RESUMO

OBJECTIVES: To investigate the epidemiology of falciparum malaria in workers from a highland tea plantation in western Kenya with very seasonally limited malaria transmission to determine what factors are associated with increased risk of malaria transmission in the Kenyan highlands. DESIGN: A cross-sectional study with rolling, random subject enrollment from April 1998 through October 1999. SETTING: Highland tea plantation located at 0 degrees 22' south and 35' 17' east in the Rift Valley highlands of western Kenya, an area with seasonally limited malaria transmission. SUBJECTS: The data for the study were obtained from enrollment of outpatients from the healthcare system of a major tea company, which has 18 estates with 22,000 workers and approximately 50,000 persons eligible for health care. Of the 2796 patients evaluated during the study period, 798 cases of malaria were confirmed by positive peripheral blood smear; 1998 smear-negative patients were pressured to be non-infected and served as controls (Ratio: 2.52: 1). INTERVENTIONS: Tea estate workers do not receive malaria chemoprophylaxis, but were given easily available free treatment for any symptomatic infections. MAIN OUTCOME MEASURES: Smear-positive cases were compared with smear-negative patients for multiple demographic and disease variables, including sex, age, travel history, ethnic origin, home district transmission risk index and length of residence. Disease characteristics, including parasite types, counts and clinical symptoms, and treatments administered were described. RESULTS: Malaria was predominantly P. falciparum (>99%); asexual parasite counts ranged from 1-10,440 per mm3, with a mean of 803.6 (95% confidence interval: 695.2, 912.0). Gametocytemia was present in 7.5% of smear-positive malaria cases, but was rare in the absence of blood asexual forms (0.5%). Prior use of a variety of antimalarial drugs was extremely common and negatively predictive of parasitemia in patients presenting for clinical treatment (Pearson Chi-square 50.81, p < 0.001), as was a subjective history of previous malaria infection in the past year (F = 26.65, 14 df, p < 0.001; univariate ANOVA). Amodiaquine was the most commonly used drug to treat cases of either smear-proven or clinically suspected malaria, accounting for 56% of therapy; pyrimethamine/sulfadoxine was used to treat 27%, artemesinin 8% and chloroquine was administered to only 3%, while combination therapy was used in 5% of cases, and only a single treatment (0.1 %) was recorded using quinine. Subjects with a prior history of treatment for malaria were statistically less likely to be infected again (Pearson Chi-square 50.81, p < 0.001). Presenting with symptoms suggestive of malaria was statistically associated with parasitemia, particularly fever, headache and dizziness, (p <0.001 for all, univariate ANOVA), but in general, clinical symptoms were not an effective discriminator of malarial disease. Ethnic group predicted malaria infection with groups traditionally from the Lake Victoria lowland regions having a greater prevalence of parasitemia (F = 2.04, 4. df, p = 0.002, univariate ANOVA). Parasitemia was significantly associated with age less than ten years (Pearson Chi-Square 145.99, p < 0.001), with a history of travel more than twenty kilometers from site within six weeks (Pearson Chi-square 58.28, p < 0.001) and with time since arrival on the plantation of one year or less (Pearson Chi-square 185.12, p <0.001) CONCLUSION: Lower infection rates in persons with a history of prior infection implies a protective effect; the predilection of malaria for young and immunologically naive victims was confirmed. The proclivity in some ethnic groups for travel to holoendemic areas also accounts for the strong associations between recent travel, lowland ethnic group and infection. These findings taken together suggest that importation of malaria to the highlands, as well as travel away from the highlands, are important sources of new infections among persons living and working there.


Assuntos
Malária/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Animais , Antimaláricos/uso terapêutico , Criança , Pré-Escolar , Estudos Transversais , Etnicidade/estatística & dados numéricos , Feminino , Humanos , Quênia/epidemiologia , Malária/sangue , Malária/tratamento farmacológico , Malária/parasitologia , Masculino , Pessoa de Meia-Idade , Plasmodium falciparum/isolamento & purificação , Plasmodium malariae/isolamento & purificação , Plasmodium ovale/isolamento & purificação , Distribuição por Sexo , Viagem/estatística & dados numéricos
20.
Chemosphere ; 49(8): 845-63, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12430662

RESUMO

Fire regimes have changed during the Holocene due to changes in climate, vegetation, and in human practices. Here, we hypothesise that changes in fire regime may have affected the global CO2 concentration in the atmosphere through the Holocene. Our data are based on quantitative reconstructions of biomass burning deduced from stratified charcoal records from Europe, and South-, Central- and North America, and Oceania to test the fire-carbon release hypothesis. In Europe the significant increase of fire activity is dated approximately 6000 cal. yr ago. In north-eastern North America burning activity was greatest before 7500 years ago, very low between 7500-3000 years, and has been increasing since 3000 years ago. In tropical America, the pattern is more complex and apparently latitudinally zonal. Maximum burning occurred in the southern Amazon basin and in Central America during the middle Holocene, and during the last 2000 years in the northern Amazon basin. In Oceania, biomass burning has decreased since a maximum 5000 years ago. Biomass burning has broadly increased in the Northern and Southern hemispheres throughout the second half of the Holocene associated with changes in climate and human practices. Global fire indices parallel the increase of atmospheric CO2 concentration recorded in Antarctic ice cores. Future issues on carbon dynamics relatively to biomass burning are discussed to improve the quantitative reconstructions.


Assuntos
Carbono/química , Carvão Vegetal/química , Evolução Planetária , Solo/análise , América , Sudeste Asiático , Biomassa , Dióxido de Carbono/química , Europa (Continente) , Incêndios
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