Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 787
Filtrar
1.
Forensic Sci Int ; 306: 110055, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31785512

RESUMO

Body fluid analysis has played a crucial role in ascertaining various characteristics and has greatly aided in reconstructing events during crime scene investigation. It is often presumed that crimes that involve violence and mental disturbances such as murder or sexual assault provide good sources of body fluids such as blood, saliva, semen, vaginal secretions, urine and tears. Tears are secreted in response to any emotional or stressful situations and may be found deposited on surfaces such as bedding, tissue paper or cloth. In the absence of the commonly noted body fluids such as blood or saliva, tears can play an important role that can lead to personal identification by examining the biochemistry and molecular aspects to obtain a full DNA profile. Additionally, identification of an individual may be done by carefully observing certain unique eye characteristics such as heterochromia which is highly individualistic. Characteristics of eyewear such as spectacles and contact lenses have unique properties and prescription criteria for correcting an individual's eyesight that can provide vital clues in understanding the visual ability of an individual. In crime scene investigation, the presence or absence of eyewear provides immense evidentiary value that has greatly aided in solving cases such as Janet Abaroa's Murder. This paper provides a systematic review of the possibility of using tears and eyewear for the purpose of forensic investigation and to statistically support the inferences with prescription databases which may be initiated across different populations. Forensic Optometry is yet to get streamlined along with the routinely followed investigative techniques and scientifically explored although no standard protocols exist to analyse eyewear. The use of behavioural optometry is gaining attention in the context of driving laws of different countries and is a simple but powerful indicator of abnormal behaviour. It is speculated that the last seen image referred to as an 'Optogram' of an individual may be captured in the retina since our eyes functions like a camera. Although this claim is considerably unexplored, it is quite possible that the last seen image of a criminal, objects or a place may be noted that can positively help in linking individuals at the scene of crime or identify the primary crime location. In this review, the potential for new insights into the analysis of tears, eye and eyewear characteristics have been explored.


Assuntos
Lentes de Contato , Impressões Digitais de DNA , DNA/isolamento & purificação , Óculos , Ciências Forenses/métodos , Lágrimas/química , Bases de Dados Factuais , Epitélio Anterior/química , Olho/patologia , Movimentos Oculares , Humanos , Mudanças Depois da Morte , Prescrições , Manejo de Espécimes , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Corpo Vítreo/química
2.
Nat Commun ; 10(1): 5631, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31822669

RESUMO

In nature, various types of animals will form self-organised large-scale structures. Through designing wireless actuation methods, microrobots can emulate natural swarm behaviours, which have drawn extensive attention due to their great potential in biomedical applications. However, as the prerequisite for their in-vivo applications, whether microrobotic swarms can take effect in bio-fluids with complex components has yet to be fully investigated. In this work, we first categorise magnetic active swarms into three types, and individually investigate the generation and navigation behaviours of two types of the swarms in bio-fluids. The influences of viscosities, ionic strengths and mesh-like structures are studied. A strategy is then proposed to select the optimised swarms in different fluidic environments based on their physical properties, and the results are further validated in various bio-fluids. Moreover, we also realise the swarm generation and navigation in bovine eyeballs, which also validates the proposed prediction in the ex-vivo environment.


Assuntos
Líquidos Corporais/química , Magnetismo , Robótica , Animais , Bovinos , Locomoção , Campos Magnéticos , Nanopartículas/química , Reprodutibilidade dos Testes , Corpo Vítreo/química
3.
Forensic Sci Int ; 305: 109999, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31671355

RESUMO

In the US, the use of synthetic opioids (e.g. fentanyl and derivatives) has become an increasing health issue with thousands of overdose deaths being observed since 2013. With the high mortality rate associated with these substances, postmortem analyses and interpretation of synthetic opioids has become extremely important. However, due to the novelty of these compounds, the available data are limited and provides challenges to toxicologists. The objectives of this study were (1) to develop and validate analytical methods for the determination of synthetic opioids in vitreous humor and brain, and (2) to investigate the postmortem distribution of new synthetic opioids in blood, vitreous humor, and brain tissue. Vitreous humor (0.5mL) and brain tissue (5g) homogenized in water (diluted 1:3, w/w) were extracted by mixed mode cation exchange-reversed phase solid phase extraction. Extracts were analyzed by liquid chromatography tandem mass spectrometry (LC-MSMS). The chromatographic separation was performed by reversed-phase with 0.1% formic acid in water and in acetonitrile as mobile phases in gradient mode, with a total run time of 21min. Data were acquired with ESI+ in dynamic multiple reaction mode (dMRM), monitoring 2 transitions per compound. The methods were succesfully validated following SWGTOX guidelines, with limits of quantification of 0.1ng/mL in vitreous humor and 0.1ng/g in brain. Fifty-eight authentic case samples from the New York City Office of the Chief Medical Examiner (NYC-OCME) were analyzed to assess the distribution and detectability of synthetic opioids in these postmortem samples. Of the fifteen synthetic opioids included in the method, six synthetic opioids and metabolites (4-ANPP, acetylfentanyl, fentanyl, furanylfentanyl, norfentanyl, U-47700) were detected in the authentic cases. Concentrations for most analytes were within the 0.1 to 100ng/mL or ng/g calibration range across all three matrices, with only concentrations from acetylfentanyl and U-47700 exceeding 100ng/mL or ng/g. The highest concentrations were observed in brain (except norfentanyl), followed by blood and vitreous humor. Most analytes were detected in all three matrices in a given case. This was followed by detection of an analyte in combinations of brain and another matrix or brain only. Through the case analyses, vitreous humor and brain demonstrated to be viable alternatives to blood when performing postmortem analyses of synthetic opioids. Brain exhibited a higher detectability for most analytes when compared to blood and vitreous humor.


Assuntos
Analgésicos Opioides/análise , Química Encefálica , Medicamentos Sintéticos/análise , Corpo Vítreo/química , Analgésicos Opioides/farmacocinética , Cromatografia Líquida , Toxicologia Forense , Humanos , Psicotrópicos/análise , Psicotrópicos/farmacocinética , Extração em Fase Sólida , Medicamentos Sintéticos/farmacocinética , Espectrometria de Massas em Tandem
4.
Zhonghua Yan Ke Za Zhi ; 55(10): 769-776, 2019 Oct 11.
Artigo em Chinês | MEDLINE | ID: mdl-31607066

RESUMO

Objective: To identify differentially expressed proteins between the patients with proliferative diabetic retinopathy (PDR) and vitreous floaters, and explore treatment target for PDR based on isobaric tags for relative and absolute quantification (iTRAQ) LC-MS/MS Proteomics. Method: Vitreous samples were collected from 28 eyes of patients with PDR and 4 eyes with vitreous floaters, which served as controls. For quantitative proteomics, vitreous samples were combined and proteins extracted and labeled with iTRAQ peptide-tagging reagents. Samples were fractionated by liquid chromatography (LC), analyzed by tandem mass spectrometry (MS/MS) and Gene Ontology (GO) analyses performed on differentially expressed proteins identified in the PDR samples. Results: In the PDR vitreous, 26 proteins were identified that were differentially expressed when compared to the controls. Of these, 7 showed a significant increase (P<0.05) and 19 a significant decrease (P<0.05)in expression in PDR patients. These included some high abundance proteins including Retinoic acid receptor reactive protein 2 (PDR 1=85.0, PDR 2=83.0, Control 1=119.6, Control 2=120.2, FC=0.710, P=0.001), Semaphorin-4B(PDR 1=64.4, PDR 2=68.8, Control 1=135.4, Control 2=146.0, FC=0.473, P=0.023), Apolipoprotein B (PDR 1=104.4, PDR 2=106.6, Control 1=89.0, Control 2=85.3, FC=1.211, P=0.024), and Heat shock protein 70 (PDR 1=69.3, PDR 2=75.0, Control 1=137.7, Control 2=138.3, FC=0.523, P=0.026), which are closely related to the pathological mechanism of PDR. GO analysis clustered the differentially expressed genes into three major functional domains: Biological Processes, Molecular Function and Cellular Component. Differential gene expression was found in the categories of cellular metabolism, organonitrogen compound and carbohydrate derivative metabolic processes, transferase activity and transmembrane signaling receptor activity. KEGG Pathway analysis indicate that Chemerin signaling through Akt, Sema4B signaling via PI3K, and HIF-1α signal pathways were all altered in the PDR samples. Conclusions: In this study we identified variations in expression of genes extensively involved in key biological processes in the retina including neovascularization, cellular metabolism and transmembrane signaling, which provide new insights into the pathophysiology of PDR. Extracellular matrix was degraded and endothelial cell migration was induced by Chemerin, in addition, the destruction of blood-retinal barrier and neuronal apoptosis were induced by ApoB. Chemerin and ApoB accelerated the development of PDR. Sema 4B participated in vascular protection, HSP70 conducted anti-apoptosis. These two cytokines protected the retinal neurovascular in PDR patients. Therefore, Chemerin, Sema 4B, ApoB and HSP70 may be the treatment target for PDR. (Chin J Ophthalmol, 2019, 55:769-776).


Assuntos
Diabetes Mellitus Tipo 2/complicações , Retinopatia Diabética/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Corpo Vítreo/metabolismo , Biomarcadores/metabolismo , Estudos de Casos e Controles , Quimiocinas/metabolismo , Cromatografia Líquida/métodos , Diabetes Mellitus Tipo 2/metabolismo , Ensaio de Imunoadsorção Enzimática , Humanos , Proteoma/análise , Espectrometria de Massas em Tandem/métodos , Corpo Vítreo/química
5.
J Forensic Leg Med ; 68: 101868, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31585334

RESUMO

The aim of this study was to analyze the prevalence of ethanol in individuals (277) subjected to a mandatory medico-legal autopsy in the Institute of Legal Medicine of Las Palmas (Canary Islands, Spain) during 2016-2017, comparing the results with data published in 2015. Blood and/or vitreous humor samples were analyzed by gas chromatography. 31.8% of the individuals were positive to ethanol. We observed a decrease in the prevalence of ethanol among males (p = 0.002). While the prevalence of ethanol was reduced, the concentration among those positive subjects has increased. 11.9% of the series died in a traffic accident and the percentage of positive to ethanol decreased in relation to 2015 (64.3, 25.0, and 35.3%). The number of suicides remains constant, although the age of the suiciders has been significantly reduced (p = 0.022). The results of this study indicate that ethanol is still heavily involved in non-natural deaths.


Assuntos
Acidentes de Trânsito/mortalidade , Depressores do Sistema Nervoso Central/análise , Etanol/análise , Violência/estatística & dados numéricos , Corpo Vítreo/química , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Distribuição por Sexo , Espanha/epidemiologia , Adulto Jovem
6.
Pol J Vet Sci ; 22(3): 445-455, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31560465

RESUMO

Eye fluids (aqueous humour and vitreous humour) may be helpful in estimating ante-mortem blood levels, since some parameters measured in these fluids have proved to be stable or to change in a predictable way after death. This would help in diagnosing the cause of death in some diseases or to evaluate ante-mortem blood levels in certain animals not easy to handle or with difficult access. In order to establish reference values of some parameters in blood and eye fluids (aqueous humour and vitreous humour), as well as the possible correlation among these three different fluids, various minerals and electrolytes (Ca, P, Mg, K, Na, Fe, Cr, Co, Ni, Cu, Zn, Se and Mo) were measured in 15 four to five year-old Lidia bulls, all dying after a period of significant stress and major exertion. Plasmatic values of Mg and P were much greater than reported in the literature. In general, mineral plasmatic values were greater than those found in ocular fluids (aqueous and vitreous), while Na, K and Cr were similar in the three fluids. We have verified the existence of correlations in P, Co and Mo among the three fluids measured, and between Se of plasma and vitreous humour. But the most marked correlations were observed in Mo (plasma -aqueous humour, r = 0.893, plasma-vitreous humour, r = 0.945, HA -HV, r = 0.849), in P (plasma-vitreous humour, r = 0.726) and in Co (plasma-vitreous humour, r = 879).


Assuntos
Humor Aquoso/química , Bovinos/sangue , Bovinos/fisiologia , Minerais/sangue , Condicionamento Físico Animal , Corpo Vítreo/química , Animais , Masculino , Minerais/química
7.
Anal Chim Acta ; 1083: 150-156, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31493805

RESUMO

Most of the on-site approaches for inferring of the post-mortem interval are still based on observative data from the direct body inspection, whereas, objective and quantitative analyses, such as potassium in the vitreous humor, are require laboratory instrumentation and skilled personnel. The present paper presents a simple and low cost analytical method suitable for use at the crime scene for inferring the time since death. The method uses a microfluidic paper-based device (µPAD) for the determination of ammonium in the vitreous humor (VH) based on the selective interaction between the ammonium and the Nessler's reagent. The color change was measured in terms of "RGB distance" by using a simple and free smartphone application. The optimized device showed a limit of detection of 0.4 mmol L-1, with between days precision less than 9.3% expressed as relative standard deviation, and accuracy between days from 94.5% to 104.5%. The selectivity of the Nessler's reaction was tested towards the main vitreous humor compounds, and no significant interferences were found. This paper-based analytical device was successfully used for the determination of ammonium ion in VH samples from forensic autopsies. The results obtained with the proposed method, although for a limited number of cases (n = 25), showed a close correlation with the data obtained with an instrumental analysis based on capillary electrophoresis. Moreover, in order to make the evaluation of results as simple as possible, a direct correlation between the color intensity, expressed as RGB distance, and the post-mortem interval was studied and a significant correlation was found (R2 > 0.78). In conclusion, the present preliminary study showes that the proposed device could be an additional tool to the traditional methods for a more accurate, although still presumptive, estimation of the time of death directly at the crime scene.


Assuntos
Compostos de Amônio/análise , Medicina Legal/métodos , Papel , Mudanças Depois da Morte , Corpo Vítreo/química , Adulto , Idoso , Colorimetria/instrumentação , Colorimetria/métodos , Medicina Legal/instrumentação , Humanos , Iodetos/química , Limite de Detecção , Compostos de Mercúrio/química , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Pessoa de Meia-Idade , Estudo de Prova de Conceito , Reprodutibilidade dos Testes , Fatores de Tempo , Adulto Jovem
8.
Leg Med (Tokyo) ; 40: 22-25, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31307009

RESUMO

Insulin overdoses have been mostly described in literature as accidental and suicidal deaths, especially in diabetic patients. The present case study deals with a 68 years old male found dead in his bedroom. The victim worked as health care professional in a rescue team, suffering from depression for several years. At the death scene, two ampoules of soluble insulin were recovered close to the body, one of which was empty. At autopsy, no signs of trauma and no injection marks were found at common sub-cutaneous or intravenous injection sites. No other remarkable findings, but hemorrhagic pulmonary edema along with astrogliosis and neuronal degeneration/necrosis in the subcortical regions and corpus callosum were observed. The blood specimen was inadequate due to hemolysis, since it was not centrifugated soon after sampling. Biochemical analysis was performed on bilateral samples of vitreous humor by using electro-chemiluminescence immunoassay (CLEIA). The insulin concentration was 61.11 mU/L in the right vitreous humor and 74.23 mU/L in the left one; the C-peptide concentration was 0.166 ng/mL in right vitreous and 0.157 ng/mL in the left one. The results are in agreement with levels of insulin and C-peptide detected in previous case studies. Based on these findings the cause of death was determined as suicidal insulin overdoses probably by sublingual administration. This way of self-administration was a diagnosis for exclusion as it has been demonstrated that sublingual human insulin has hypoglycemic effects similar to insulin injected. The case study emphasizes the potential role of vitreous humor as reliable alternative substrate for biochemical analysis compared to post-mortem serum or blood samples in cases of fatal insulin intoxication. Furthermore, the CLEIA is an encouraging analytical method to be considered in such cases, although still not validated to perform quantitative analysis of post-mortem fluids.


Assuntos
Overdose de Drogas/diagnóstico , Insulina/administração & dosagem , Suicídio , Corpo Vítreo/química , Idoso , Autopsia , Diagnóstico Diferencial , Humanos , Masculino
9.
Forensic Sci Int ; 300: e34-e37, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31056341

RESUMO

The significant increase in the number of new psychoactive substances on the drug market has recently been a serious problem. The manuscript presents a fatal case of suicide poisoning with 3-MMC (3-methylmethcathinone). The biological material collected during the autopsy of a 19-year-old woman, transferred to the toxicological Laboratory in Katowice ToxLab, was subjected to a chemical and toxicological analysis. The toxicological analysis of blood, vitreous humor and gastric contents revealed 3-methylmetcatinone at a concentration of 800 ng/ml, 153 ng/ml and 5,5 mg, respectively. The presence of 3-MMC has also been confirmed in physical evidence secured on site. 3-methylmethcathinone is a dangerous psychoactive substance that caused the death of the 19-year-old.


Assuntos
Drogas Desenhadas/envenenamento , Metanfetamina/análogos & derivados , Psicotrópicos/envenenamento , Drogas Desenhadas/análise , Feminino , Conteúdo Gastrointestinal/química , Humanos , Metanfetamina/análise , Metanfetamina/envenenamento , Psicotrópicos/análise , Suicídio , Corpo Vítreo/química , Adulto Jovem
10.
J Forensic Sci ; 64(3): 778-785, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30931532

RESUMO

Vitreous humor (VH) and synovial fluid (SF) become optional postmortem samples for biochemistry investigation. However, few studies have explored SF as a potential source, and there is still controversy whether the biochemical concentrations in bilateral VH are the same. We explored the concentrations of biochemical substances in both VH and SF, and compared between both sides and between the fluids. We also correlated the biochemical concentrations in both fluids. All samples were centrifuged after collection and the supernatant fluids were used for the analysis. The results indicated no significant difference in the constituent concentrations between the fluids from both sides (p > 0.05). Sodium, potassium, chloride, and magnesium concentrations were significantly higher in the VH, but in vice versa for glucose, uric acid, and creatinine concentrations (p < 0.001). Sodium, potassium, glucose, lactate, urea, uric acid, and creatinine concentrations between both fluids showed significant correlation (p < 0.05), but not chloride and magnesium concentrations.


Assuntos
Líquido Sinovial/química , Corpo Vítreo/química , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cloretos/análise , Estudos de Coortes , Correlação de Dados , Creatinina/análise , Feminino , Medicina Legal , Glucose/análise , Humanos , Lactatos/análise , Magnésio/análise , Masculino , Pessoa de Meia-Idade , Potássio/análise , Análise de Regressão , Sódio/análise , Ácido Úrico/análise , Adulto Jovem
11.
J Forensic Leg Med ; 63: 18-25, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30844584

RESUMO

BACKGROUND: In South Africa, violence-related injury and mortality contributes highly to the nation's burden of injury. Drug abuse, which is also reported to be rife across the county, has been associated with violence, resulting injury, and death. While post-mortem toxicological investigations are comprehensive and routine in violent fatalities internationally; this is not currently the case in South Africa. OBJECTIVES: To conduct a post-mortem toxicological investigation on a cohort of violent fatalities in the West-Metropole of Cape Town, Western Cape. METHODS: The study included a prospective toxicological analysis and a retrospective review of the corresponding blood alcohol results on a small cohort of victims of violent death (whether homicidal, non-overdose suicidal, or accidental) admitted to the Salt River State Mortuary in Cape Town. Biological specimens were collected from the victims following informed consent from the next-of-kin, and a targeted screening approach using liquid chromatography coupled to tandem mass spectrometry was used for the qualitative toxicology analysis. At the Forensic Chemistry National Laboratory, blood alcohol testing was conducted using a headspace gas chromatography with flame ionisation detector according to national standards. Data was analysed with regards to demographics, circumstances of death, and toxicological results. RESULTS: Consent was obtained for 104 violent death cases, autopsied between August-October 2015, most were male victims of homicide (n = 92, 88%). Volatiles analysis for ethanol was performed on 98% of cases, with 41% testing positive (>0.01 g/100 mL). Other drugs of abuse were detected in 63 (61%) cases and more than one substance were present in 51 (49%) cases. The most commonly detected substances were combinations of methamphetamine, diphenhydramine, and methaqualone. CONCLUSIONS: A high prevalence of drugs of abuse was identified in a cohort of victims of violent death. Objective drug trends observed were consistent with national self-reported rehabilitation centre data and research on self-reported drug user. This study was limited by the sampling strategy, including challenges associated with obtaining consent and the rapid turnover of violent fatalities. Despite this - and to the authors' knowledge - this study provided the first prospective post-mortem toxicological investigation into violent death in South Africa. Contextually, it highlights the need for routine and comprehensive toxicology in these cases to strengthen research and service provision, so as to better understand the role of drugs in violent death.


Assuntos
Acidentes/mortalidade , Etanol/análise , Homicídio/estatística & dados numéricos , Entorpecentes/análise , Preparações Farmacêuticas/análise , Suicídio/estatística & dados numéricos , Adolescente , Adulto , Idoso , Bile/química , Depressores do Sistema Nervoso Central/análise , Criança , Cromatografia Gasosa , Cromatografia Líquida , Estudos de Coortes , Feminino , Ionização de Chama , Toxicologia Forense , Humanos , Masculino , Pessoa de Meia-Idade , África do Sul/epidemiologia , Detecção do Abuso de Substâncias , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Espectrometria de Massas em Tandem , Corpo Vítreo/química , Adulto Jovem
12.
Acta Diabetol ; 56(7): 797-805, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30911832

RESUMO

AIMS: To compare the vitreous levels of chemokines in diabetic patients with and without retinopathy. To find the relationship between stages of diabetic retinopathy (DR) and levels of vitreous chemokines. METHODS: The study involved 20 non-diabetic and 20 diabetic patients without clinical signs of DR (NDR) and 40 diabetic patients with proliferative diabetic retinopathy (PDR). The vitreous humor was collected and the levels of 40 chemokines were measured using magnetic color-bead-based multiplex assay. RESULTS: The control group, NDR group, PDR with vitreous hemorrhage (VH) group, and PDR with tractional retinal detachment group comprised 20, 20, 21, and 19 eyes, respectively. Only the concentration of CCL3 was significantly higher in the NDR group compared with the controls (p = 0.038). Twenty-five types of chemokines were statistically higher in the PDR with VH group in comparison to NDR group (all p < 0.05). All chemokines were statistically higher in the PDR with TRD group in comparison to NDR group (all p < 0.05) apart from 3 chemokines: GM-CSF, MIF, and CCL3(p = 0.086, p = 0.109, p = 0.094, respectively). The concentration of CCL21, CCL15 in PDR with TRD group was significantly higher compared with PDR with VH group, while other 36 chemokines were not significantly different between PDR with VH group and PDR with TRD group. CONCLUSIONS: The inflammation gradually worsen with the progression of DR. CCL3 may be associated with the onset of early diabetic retinal damage, and CCL15 and CCL21 may be closely related to the formation of fibrovascular membrane and the progression of the end stage of DR.


Assuntos
Quimiocinas/análise , Quimiocinas/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Retinopatia Diabética/metabolismo , Corpo Vítreo/química , Adulto , Idoso , Estudos de Casos e Controles , Quimiocinas CC/análise , Quimiocinas CC/metabolismo , Diabetes Mellitus Tipo 2/patologia , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/patologia , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Proteínas Inflamatórias de Macrófagos/análise , Proteínas Inflamatórias de Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Corpo Vítreo/metabolismo , Corpo Vítreo/patologia
13.
J Anal Toxicol ; 43(7): 505-511, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-30926990

RESUMO

The analysis of biological specimens collected at autopsy for the presence of exogenous insulin(s) is of special interest in select death investigations as they may be suspected in the cause of a death. Technical challenges include the limited stability of insulin, and the forensic requirement of differentiating endogenous insulin from pharmaceutical analogs. A novel method was developed for the detection and quantification of human insulin, Glulisine, Lispro, Aspart, Glargine and Detemir in vitreous fluid. An immunoaffinity extraction procedure is performed followed by separation of the insulin α- and ß-chains. Liquid chromatography tandem mass spectrometry analysis of the ß-chain allows for the unequivocal identification of each insulin analog. The analytical measurement range for each insulin was 0.5-25 ng/mL. The method was evaluated for accuracy, precision, carryover, interferences and stability. Eight vitreous fluid samples collected from cases where untoward insulin use was suspected were subjected to analysis. Positive results were obtained from three samples, and a detailed case history is provided for one of these cases. Even though insulin instability in postmortem biological fluid remains a challenge, this method allows for a reliable forensic-level analysis in vitreous fluid.


Assuntos
Overdose de Drogas/diagnóstico , Toxicologia Forense/métodos , Insulina/análogos & derivados , Insulina/análise , Corpo Vítreo/química , Adulto , Feminino , Toxicologia Forense/instrumentação , Humanos , Insulina Aspart , Insulina Glargina , Insulina Lispro , Suicídio , Fluxo de Trabalho
14.
J Forensic Sci ; 64(4): 1105-1111, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30731020

RESUMO

Gabapentin, a GABA analogue, is a nonopioid prescribed for seizure control and neuralgic pain. Its abuse for recreational purposes has been increasing in recent years as the number of prescriptions also increases. In our series, we review 104 cases of decedents who tested positive for gabapentin in postmortem blood samples and an additional 53 nonfatal cases of motor vehicle drivers suspected of driving under the influence. In 47.1% of the fatality cases, gabapentin was directly involved in death. Most gabapentin fatalities had several other intoxicants present (opioids, over-the-counter medications, antianxiety, and antidepressant medications). In cases in which gabapentin was determined to be a cause of death, the blood concentrations ranged from 1.1 to 134.0 mg/L. Persons who died of a gabapentin-related drug death were prescribed the drug legitimately 91.4% of the time, with 84.2% of those also having a known prior history of abuse or misuse of prescription medications.


Assuntos
Gabapentina/efeitos adversos , Gabapentina/análise , Uso Indevido de Medicamentos sob Prescrição/mortalidade , Transtornos Relacionados ao Uso de Substâncias/mortalidade , Acidentes/mortalidade , Cromatografia Líquida , Dirigir sob a Influência/estatística & dados numéricos , Overdose de Drogas , Feminino , Homicídio/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Mudanças Depois da Morte , Estudos Retrospectivos , Detecção do Abuso de Substâncias , Transtornos Relacionados ao Uso de Substâncias/sangue , Suicídio/estatística & dados numéricos , Espectrometria de Massas em Tandem , Virginia/epidemiologia , Corpo Vítreo/química
15.
Clin Microbiol Infect ; 25(11): 1364-1369, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30771529

RESUMO

BACKGROUND: Adjunctive systemic antibiotic therapy for treatment of bacterial endophthalmitis is controversial but common practice due to the severity of the disease. In the absence of guidance documents, several antibiotic regimens are being used without applying evidence-based prescribing, leading to inappropriate treatment of this serious eye condition. OBJECTIVES: To summarize available data on intravitreal penetration of systemically administered antibiotics and to discuss their usefulness from a microbiological and pharmacological point of view. SOURCES: We performed a systematic PubMed search of studies investigating antibiotic concentrations in the vitreous after systemic administration in humans, and selected animal models. CONTENT: The best-documented agents achieving therapeutic levels in the vitreous are meropenem, linezolid and moxifloxacin. Vancomycin, cefazoline, ceftriaxone, ceftazidime, imipenem and trimethoprim-sulfamethoxazole reach levels justifying their use in specific situations. Available data do not support the use of ciprofloxacin, levofloxacin, aminoglycosides, aminopenicillins, piperacillin, cefepime and clarithromycin. With very limited but available promising data, the use of daptomycin and rifampicin deserves further investigation. IMPLICATIONS: The choice of the adjunctive systemic antibiotic agent-in situations where it is considered relevant for treatment-must to date be made on an individual basis, considering microbiological aspects as well as operative status and inflammation of the eye. This review gives a systematic overview of antibiotic options and provides guidance to the clinician striving for optimal systemic antibiotic treatment of bacterial endophthalmitis.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Infecções Bacterianas/tratamento farmacológico , Endoftalmite/tratamento farmacológico , Corpo Vítreo/química , Administração Intravenosa , Animais , Modelos Animais de Doenças , Humanos
16.
PLoS One ; 14(1): e0209217, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30615640

RESUMO

PURPOSE: To characterize the biophysical properties of an artificial vitreous body substitute (VBS), which consists of a biocompatible, cross-linked, hyaluronic acid (HA)-based hydrogel, by analysing the VBS's influence on intraocular pressure (IOP) and retinal integrity in distinct ex vivo eye models in order to evaluate the its potential for in vivo biocompatibility testing. METHODS: Pig eyes were obtained immediately postmortem, and VBS was injected after core-vitrectomy. IOP was followed for 24 h (n = 5). VBS influence on retinal integrity was investigated using isolated bovine retinas superfused with an oxygen saturated nutrient solution. An electroretinogram (ERG) was recorded on explanted bovine retinae using silver/silver chloride electrodes; after application of VBS for 2 min, a washout period of 70 min was employed. The percentage of a-and b-wave reduction at the end of the washout phase was compared to baseline values (n = 5). Data were calculated throughout as the mean and the standard deviation. qRT-PCR (Bax/Bcl-2-ratio, GFAP- and PGP9.5-levels) or western blot analysis was used to test for toxicity of Princess Volume after 24 h (and ß-3 tubulin with GAPDH as a control gene). Significance was estimated by Student´s t-test; p ≤0.05 was considered to be statistically significant. RESULTS: The IOP increased non-significantly by 10% after 24 h. Short-term biocompatibility testing using isolated superfused bovine retinas showed neither significant reductions of the b-wave nor the a-wave amplitudes (b-wave reduction 14.2%, p>0.05; a-wave reduction 23.9%, p>0.05). qRT-PCR and western blot analysis did not reveal significant toxicity after 24 h. CONCLUSIONS: The manufactured HA-based hydrogel showed highly favourable biophysical characteristics in the explored ex vivo models, justifying in vivo studies enabling the assessment of biocompatibility.


Assuntos
Materiais Biocompatíveis/química , Corpo Vítreo/química , Animais , Fenômenos Biofísicos , Bovinos , Reagentes para Ligações Cruzadas , Eletrorretinografia , Ácido Hialurônico/química , Hidrogéis/química , Técnicas In Vitro , Pressão Intraocular , Teste de Materiais , Refratometria , Retina/fisiologia , Reologia , Sus scrofa , Vitrectomia , Corpo Vítreo/fisiologia , Corpo Vítreo/cirurgia
17.
Forensic Sci Int ; 295: 157-168, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30611119

RESUMO

The estimation of the time elapsed since death is of paramount importance in the field of forensic sciences and criminal investigation, owing, among other factors, to the possible legal repercussions. Over the past few years various formulae have been developed to calculate this interval using a combination of different statistical methods and the concentrations of substances found in the vitreous humor. Corrective factors, such as ambient temperature, cause of death or age, which can modify the concentration of these substances and therefore the estimation of the postmortem interval, have been incorporated into models. In this paper five simple and reliable models to estimate PMI based the on the analysis of potassium, hypoxanthine and urea in the vitreous humor are presented. Corrective factors, such as body weight, rectal temperature and ambient temperature, which can influence the estimation of this interval have been incorporated into the formulae. Finally, the R2 and the mean squared error have been calculated for each model in order to select the best of the five. A free software program which calculates the PMI from the model and parameters used is available from the authors. It provides quick and reliable results as well as the error committed and R2 for each case.


Assuntos
Temperatura Corporal , Peso Corporal , Mudanças Depois da Morte , Corpo Vítreo/química , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Hipoxantina/análise , Pessoa de Meia-Idade , Modelos Estatísticos , Potássio/análise , Ureia/análise , Adulto Jovem
18.
Am J Forensic Med Pathol ; 40(3): 258-261, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30663990

RESUMO

To ascribe a cause of death from drowning in a body immersed in water can be difficult because of the absence of specific postmortem findings and unreliable ancillary tests. Postmortem vitreous biochemical analysis is documented to be a useful adjunct ancillary test to aid the diagnosis of saltwater drowning. A major confounding factor in using postmortem vitreous is the effect of electrolyte diffusion and water osmosis during immersion. A recent animal study suggested that cerebrospinal fluid (CSF) biochemical analysis, which is unaffected by immersion, may be an alternative. However, to date, there are no human data to support this. We report a saltwater drowning death from presumed suicide in which the postmortem CSF sodium and chloride level was elevated compared with nonimmersion deaths. This case gives evidence to support the potential use of postmortem CSF sodium and chloride level as an adjunct to the diagnosis of saltwater drowning.


Assuntos
Cloretos/líquido cefalorraquidiano , Afogamento/diagnóstico , Água do Mar , Sódio/líquido cefalorraquidiano , Suicídio , Biomarcadores/líquido cefalorraquidiano , Medicina Legal , Humanos , Masculino , Pessoa de Meia-Idade , Corpo Vítreo/química
19.
J Anal Toxicol ; 43(5): 385-391, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30668758

RESUMO

Mercury is a heavy metal with high toxicity, the level of which depends on the form of the metal. One of the newer techniques for determining trace amounts of total mercury in various materials, including biological samples, is thermal decomposition, amalgamation and atomic absorption spectrometry (TDA AAS). The TDA AAS method was optimized and validated using a mercury analyzer (DMA-80). The limits of detection for mercury were 0.10 and 0.20 µg/L (nickel and quartz boats, respectively). The working range of the calibration curve was at least from 0.6 to 200 ng Hg/mL; the intra-day precision in samples (RSD)-in the range of: 1.66-6.86% (blood), 0.82-1.47% (urine) and 2.01-3.44% (hair); the inter-day precision (over 8 days): 2.51%, and 2.5% (blood spiked with 2.5 and 10 ng Hg, respectively), 5.10% and 3.16% (urine spiked with 2.0 and 6.0 ng Hg, respectively). The accuracy (as relative error, mean value) determined on the basis of the study of reference materials of blood (Seronorm Trace Elements Whole Blood L-1, L-2, L-3), urine (Seronorm Trace Elements Urine, Urine L-2), and hair (Human Hair NIES CRM No. 13) was: 2.00% (blood), 0.50% (urine) and 0.86% (hair); recovery of 2.5 ng Hg (blood): 93-97%. The method was used for the determination of mercury in 76 samples of various biological matrices, including samples of whole blood, urine, hair, bile and vitreous humor. Mercury concentrations in postmortem blood (n = 24) were in the range: 0.61-12.4 µg/L (median 3.02 µg/L); urine (n = 12): 0.16-2.19 µg/L (median 0.81 µg/L); hair (n = 14): 0.08-0.53 µg/g (median 0.22 µg/g); bile (n = 12): 1.15-7.11 µg/L (median 2.41 µg/L and vitreous humor (n = 13): 0.22-1.01 µg/L (median 0.47 µg/L). The method is suitable for the purposes of forensic toxicology analysis.


Assuntos
Toxicologia Forense/métodos , Intoxicação por Mercúrio/diagnóstico , Mercúrio/análise , Espectrofotometria Atômica , Bile/química , Calibragem , Toxicologia Forense/instrumentação , Cabelo/química , Humanos , Limite de Detecção , Mercúrio/sangue , Mercúrio/urina , Intoxicação por Mercúrio/sangue , Intoxicação por Mercúrio/urina , Mudanças Depois da Morte , Padrões de Referência , Reprodutibilidade dos Testes , Corpo Vítreo/química
20.
Eur J Pharm Biopharm ; 136: 102-107, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30660691

RESUMO

The intravitreal route faces many challenges in rapidly and effectively reaching posterior eye pathology, with administered therapeutics experiencing non-specific distribution around and premature clearance from ocular tissues. Nanobubbles and ultrasound may improve outcomes of intravitreally administered drugs by influencing the directionality of drug-containing particle migration. In this study, we assessed the impact of trans-scleral or corneal ultrasound application on the distribution of intravitreally-injected nanobubbles. Rhodamine-tagged gas entrapped nanobubble formulations were prepared and injected into ex vivo bovine and porcine eyes and subjected to ultrasound (1 MHz, 0-2.5 W/cm2, 50-100% duty, 60 s). Bovine eyes were partially dissected to visualize the vitreous humor and particle migration was evaluated via optical fluorescence spectroscopy. Directional migration in porcine eyes was evaluated using a snap freezing protocol complemented by quantification of regional fluorescence. The impact on nanobubble migration following pars-plana injection and sequential ultrasound cycle application from scleral or corneal-surface positions was also assessed. Administration of ultrasound significantly enhanced the directional migration of nanobubbles in both ex vivo models, with multiple corneal ultrasound cycles promoting greater migration of dye-filled nanobubbles to posterior regions of the vitreous. Moreover, particles moved in a directional manner away from the ultrasound wave source demonstrating an ability to effectively control the rate and path of nanobubble migration. These findings establish an encouraging new and safe modality enabling rapid distribution of intravitreally-injected therapeutics where expeditious therapeutic intervention is warranted.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Corantes Fluorescentes/análise , Injeções Intravítreas/métodos , Nanocápsulas/análise , Ondas Ultrassônicas , Corpo Vítreo/química , Animais , Bovinos , Corantes Fluorescentes/administração & dosagem , Corantes Fluorescentes/metabolismo , Nanocápsulas/administração & dosagem , Espectrometria de Fluorescência/métodos , Suínos , Corpo Vítreo/efeitos dos fármacos , Corpo Vítreo/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA