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The article published in Marine Mammal Science explores the use of postmortem vitreous humor (VH) biochemistry as a proxy for antemortem blood analyte concentrations in delphinids. The study analyzed samples from stranded delphinids, including bottlenose dolphins, common dolphins, Risso's dolphins, and white-beaked dolphins. Results indicated that certain analytes, such as urea nitrogen (UN) and chloride (Cl), showed high agreement between VH and serum/plasma concentrations, while others like creatinine (CREA) and osmolality (Osmol_calc) displayed consistent differences. The study highlights the potential forensic utility of VH biochemistry in delphinids, providing valuable insights into antemortem health status and metabolic state. [Extracted from the article]

Pegcetacoplan is a complement C3/C3b inhibitor indicated for the treatment of geographic atrophy (GA). A population pharmacokinetic (PK)/pharmacodynamic (PD) analysis of pegcetacoplan used GA lesion area measurements from three clinical studies to determine the effect of pegcetacoplan exposure on GA progression. A base disease progression model was developed using data from sham‐treated eyes and untreated fellow eyes, followed by treatment effect assessment in dose–response and PK/PD models. In total, 1501 patients from FILLY (NCT02503332), OAKS (NCT03525613), and DERBY (NCT03525600) received intravitreal pegcetacoplan 15 mg monthly or every other month (EOM) or sham treatment monthly or EOM and were included in the population analysis of lesion area. Disease progression over time was adequately described as linear‐with‐time over the 24‐month maximal study duration. Disease‐specific covariates associated with slower lesion growth were unilateral, unifocal, and subfoveal GA lesions and >20 intermediate or large drusen groups (≥63 μm) at baseline. The dose–response model estimated 0.80‐fold (95% CI: 0.75, 0.84) and 0.83‐fold (95% CI: 0.78, 0.87) reductions in GA lesion growth rate with pegcetacoplan monthly and EOM, respectively, versus sham. A relationship between vitreous humor concentration and GA lesion growth rate was quantified as 2.6% per unit of log‐transformed vitreous pegcetacoplan concentration in the PK/PD model. PK/PD predictions of treatment effect based on exposure (pegcetacoplan monthly: 0.80 [90% CI: 0.77, 0.84]; pegcetacoplan EOM: 0.83 [90% CI: 0.80, 0.86]) were consistent with predictions based on dose response. These results support the benefit of pegcetacoplan administered monthly or EOM in slowing GA lesion growth. [ABSTRACT FROM AUTHOR]

Natural‐derived biomaterials can be used as substrates for the growth, proliferation, and differentiation of cells. In this study, bovine vitreous humor as a biological material was cross‐linked to silk fibroin with different concentration ratios to design a suitable substrate for corneal tissue regeneration. The cross‐linked samples were evaluated with different analyses such as structural, physical (optical, swelling, and degradation), mechanical, and biological (viability, cell adhesion) assays. The results showed that all samples had excellent transparency, especially those with higher silk fibroin content. Increasing the ratio of vitreous humor to silk fibroin decreased mechanical strength and increased swelling and degradation, respectively. There was no significant difference in the toxicity of the samples, and with the increase in vitreous humor ratio, adhesion and cell proliferation increased. Generally, silk fibroin with vitreous humor can provide desirable characteristics as a transparent film for corneal wound healing. [ABSTRACT FROM AUTHOR]

Transfer RNA‐derived fragments (tRFs) represent a novel class of non‐coding RNA transcripts that possess specific biological functions. However, the involvement of tRFs in retinal microvascular diseases remains poorly understood. In this study, we aimed to reveal whether modulation of tRF‐30 expression could attenuate pathological retinal neovascular diseases. Our findings demonstrate a significant upregulation of tRF‐30 expression levels in both in vivo models of diabetic retinopathy (DR) and in vitro endothelial sprouting models. Conversely, inhibition of tRF‐30 expression suppressed the formation of abnormal neovascularization in the retina in vivo, while reducing the proliferation and migration activity of retinal vascular endothelial cells in vitro. We also found that tRF‐30 modulates retinal neovascularization through the tRF‐30/TRIB3/signal transducer and activated transcription 3 signaling pathway. Furthermore, we validated a significant upregulation of tRF‐30 expression levels in the vitreous humor of DR patients, with high levels of both validity and specificity in diagnostic testing. Collectively, our findings highlight a pro‐angiogenic role for tRF‐30 in DR. Intervening in the tRF‐30 signaling pathway may represent a promising prevention and treatment strategy for retinal angiogenesis. [ABSTRACT FROM AUTHOR]

Extremely preterm infants are at risk of developing retinopathy of prematurity (ROP), characterized by neovascularization and neuroinflammation leading to blindness. Polyunsaturated fatty acid (PUFA) supplementation is recommended in preterm infants to lower the risk of ROP, however, with no significant improvement in visual acuity. Reasonably, this could be as a result of the non‐consideration of PUFA metabolizing enzymes. We hypothesize that abnormal metabolism of the arachidonic acid (AA) pathway may contribute to severe stages of ROP. The present study investigated the AA‐metabolizing enzymes in ROP pathogenesis by a targeted gene expression analysis of blood (severe ROP = 70, No/Mild = 56), placenta (preterm placenta = 6, full term placenta = 3), and human primary retinal cell cultures and further confirmed at the protein level by performing IHC in sections of ROP retina. The lipid metabolites were identified by LC–MS in the vitreous humor (VH; severe ROP = 15, control = 15). Prostaglandins D2 (p = 0.02), leukotrienes B5 (p = 0.0001), 11,12‐epoxyeicosatrienoic acid (p = 0.01), and lipid‐metabolizing enzymes of the AA pathway such as CYP1B1, CYP2C8, COX2, and ALOX15 were significantly upregulated while EPHX2 was significantly (0.04) downregulated in ROP cases. Genes involved in hypoxic stress, angiogenesis, and apoptosis showed increased expression in ROP. An increase in the metabolic intermediates generated from the AA metabolism pathway further confirmed the role of these enzymes in ROP, while metabolites for EPHX2 activity were low in abundance. Inflammatory lipid intermediates were higher compared to anti‐inflammatory lipids in VH and showed an association with enzyme activity. Both the placenta of preterm infants who developed ROP and hypoxic retinal cultures showed a reduced expression of EPHX2. These findings suggested a strong involvement of EPHX2 in regulating retinal neovascularization and inflammation. The study results underscore the role of arachidonic acid metabolism in the development of ROP and as a potential target for preventing vision loss among preterm‐born infants. [ABSTRACT FROM AUTHOR]

To date, synovial fluid has not been the subject of targeted analysis as a possible substrate to search for the presence of diatoms in the forensic context of drowning. However, its unique characteristics of production and isolation from the external environment could make it suitable for this purpose, similar to what has already been demonstrated in the literature for vitreous humor. By considering this, synovial fluid was analyzed in a specific case that came to our attention, where the coexisting signs of polytrauma and drowning were documented during autopsy, demonstrating a period of vitality during immersion. After a thin smear of the supernatant was obtained from the centrifugation of the synovial fluid sample, diatoms were successfully detected, consistent with those found in other organs and the water of the canal. The detection of diatoms in the synovial fluid was an objective finding, but its generalizability is limited because this was a pilot application. However, in cases where death by drowning is suspected and the body has multiple areas breached by trauma, the technique of analyzing diatoms in the synovial fluid could have great potential. Therefore, it is appropriate to further explore this technique in order to obtain more forensic evidence in such a setting. [ABSTRACT FROM AUTHOR]

This technical note reviews the plethora of concentration units used to report blood‐alcohol concentration (BAC) and breath‐alcohol concentrations (BrAC) for legal purposes in different countries. The choice of units sometimes causes confusion when scientific papers originating from a certain country might be introduced into evidence via expert testimony, such as when alcohol‐related crimes are prosecuted. The concentration units are also important to consider when blood/breath ratios (BBRs) of alcohol are calculated and compared between countries. Statutory BAC limits for driving in most nations are reported in mass/volume (m/v) units, such as g/100 mL (g%) in the United States, mg/100 mL (mg%) in the United Kingdom and Republic of Ireland, or g/L (mg/mL) in many EU nations. By contrast, Germany and the Nordic countries report BAC as mass/mass (m/m) units, hence g/kg or mg/g, which are ~5.5% lower than m/v units, because whole blood has an average density of 1.055 g/mL. There are historical reasons for reporting BAC in mass/mass units because the aliquots of blood analyzed were measured by weight rather than volume. The difference between m/m and m/v is also important in postmortem toxicology, such as when distribution ratios of ethanol between blood and other biological specimens, such as urine, vitreous humor, and cerebrospinal fluid, are reported. [ABSTRACT FROM AUTHOR]

Topotecan (TPT) is used in the treatment of retinoblastoma, the most common malignant intraocular tumor in children. TPT undergoes pH‐dependent hydrolysis of the lactone ring to the ring‐opened carboxylate form, with the lactone form showing antitumor activity. A selective, and highly sensitive ultra‐high‐performance liquid chromatography‐tandem mass spectrometry method was developed for the determination of both forms of TPT in one mobile phase composition in plasma and vitreous humor matrices. The method showed an excellent linear range of 0.375–120 ng/mL for the lactone. For the carboxylate, the linear range was from 0.75 to 120 ng/mL. The matrix effect and the recovery for the lactone ranged from 98.5% to 106.0% in both matrices, for the carboxylate form, it ranged from 94.9% to 101.2%. The dynamics of the transition between TPT lactone and TPT carboxylate were evaluated at different pH environments. The stability of TPT forms was assessed in plasma and vitreous humor at 8 and 37°C and a very fast conversion of lactone to carboxylate form occurred at 37°C in both matrices. The method developed facilitates the investigation of TPT pharmacodynamics and the release kinetics in the development of the innovative local drug delivery systems. [ABSTRACT FROM AUTHOR]

Purpose. The aim of this report is to present the onset of bilateral endophthalmitis negative to culture testing and vitreous tapping in a postpartum immunocompetent patient. Methods. A 33-year-old patient developed floaters and severe blurry vision in both eyes 3 weeks after childbirth. With no previous surgery, no comorbidities in her clinical history, and negative diagnostic reports, endogenous endophthalmitis was suspected. Two days later, a pars plana vitrectomy was performed in both eyes one week apart, and intravitreal antibiotics and antifungals were administered during the surgery. No infectious source was identified since the cultures from the aqueous and vitreous humor returned negative in both cases. Results. Residual fibrosis around the fovea in the right eye and on the optic disc in the left eye was described. Nevertheless, the best corrected visual acuity of the patient was 20/20 in both eyes 4 months after the onset of the presumed endogenous endophthalmitis. Conclusion. This is the first report presenting a bilateral case of postpartum endophthalmitis negative to culture testing and vitreous tapping in a healthy patient with no previous surgeries nor long-term treatment. Early pars plana vitrectomy was fundamental for the correct management of this condition. [ABSTRACT FROM AUTHOR]

Kratom is a plant originating in Southeast Asia that has been used for its dose‐dependent stimulant and opioid effects. The main active compound in kratom is mitragynine, an alkaloid with affinity for the mu‐opioid receptor. Toxicity and fatalities related to kratom use have increased substantially in recent years. In this case report, we describe a 44‐year‐old man who was found deceased in bed. The only significant finding at autopsy was abdominal distension with >4 L of ascites. Toxicology testing was performed on femoral blood which showed 79 ng/mL of hydromorphone, 560 ng/mL of mitragynine, and 240 ng/mL of olanzapine. In addition, creatinine and urea in vitreous humor were significantly elevated, consistent with renal impairment. Death was attributed to hydromorphone toxicity with mitragynine being a contributing factor. [ABSTRACT FROM AUTHOR]

Purpose: To demonstrate MR T1 mapping in vivo as a method to non‐invasively estimate vitreous oxygen concentration in ischemic eye disease. Methods: Patients with ischemic eye disease (central retinal vein occlusion, ocular ischemic syndrome, and proliferative diabetic retinopathy) were prospectively recruited. MRI was performed on each patient before any treatment, with T1 mapping acquired using an inversion recovery TrueFISP sequence at several inversion times, from a single slice positioned through the center of both eyes in the axial oblique plane. A phantom study measuring seven different concentrations of vitronectin, a protein released in ischemic eye disease, was undertaken to determine its potential confounding effect on T1. Results: Ten participants were recruited (eight central retinal vein occlusion, one ocular ischemic syndrome, and one proliferative diabetic retinopathy). Of the eight central retinal vein occlusion cases, there was a statistically different vitreous T1 in the diseased eye compared to the healthy control eye (4.306 vs. 4.518 s, p = 0.008). T1 times did not significantly alter across the range of vitronectin concentrations. Conclusions: Ischemic eye disease decreases vitreous T1, potentially implying an increase in vitreous partial pressure of oxygen (pO2) concentration given what is known from the relationship between 1/T1 and pO2. Potential theories for this unexpected result are discussed. This study provides further data on this technique, with potential clinical application in eye disease. [ABSTRACT FROM AUTHOR]

Subnuclear vacuoles in the proximal renal tubules have been reported as a histologic sign of ketoacidosis. Originally described in diabetic ketoacidosis, renal vacuoles can be found in other ketogenic states such as alcoholic ketoacidosis (AKA), starvation, and hypothermia, underpinned by deranged fatty acid metabolism. A retrospective analysis of 133 deaths associated with alcohol use disorder (AUD) examined at autopsy between 2017 and 2020 was undertaken. This study aimed to determine the prevalence of subnuclear vacuoles in deaths of those with AUD and their specificity for deaths from AKA, and to elucidate what demographic, biochemical, and pathologic findings are associated with subnuclear vacuoles. In each case, vitreous humor biochemistry including electrolytes, glucose, and beta‐hydroxybutyrate (BHB) was analyzed alongside postmortem hemoglobin A1c and renal and liver histology. Renal histology was graded for the presence of vacuoles as absent (0), scanty (1), or easily identifiable (2). Liver histology was graded for steatosis and for fibrosis if Masson trichrome staining was available. Vacuoles were commonly seen in the deaths of those with AUD. They were seen in deaths due to AKA but were not specific to that cause of death. With vacuoles present, lower vitreous sodium (139 vs. 142 mmol/L; p = 0.005), higher vitreous BHB (1.50 vs. 1.39 mmol/L; p = 0.04), severe hepatic steatosis, and severe hepatic fibrosis were seen, compared with those without renal vacuoles. [ABSTRACT FROM AUTHOR]

A fatal case of 1,4‐butanediol (1,4‐BD) oral ingestion is reported here, in which a 51‐year‐old man was found dead in his bed. According to the police report, the deceased was a known drug user. A glass bottle labeled (and later confirmed to be) "Butandiol 1,4" (1,4‐BD) was found in the kitchen. Furthermore, the deceased's friend stated that he consumed 1,4‐BD on a regular basis. The autopsy and histological examination of postmortem parenchymatous organ specimens did not revealed a clear cause of death. Chemical‐toxicological investigations revealed gammahydroxybutyrat (GHB) in body fluids and tissues in the following quantities: femoral blood 390 mg/L, heart blood 420 mg/L, cerebrospinal fluid 420 mg/L, vitreous humor 640 mg/L, urine 1600 mg/L, and head hair 26.7 ng/mg. In addition, 1,4‐BD was qualitatively detected in the head hair, urine, stomach contents, and the bottle. No other substances, including alcohol, were detected at pharmacologically relevant concentrations. 1,4‐BD is known as precursor substance that is converted in vivo into GHB. In the synoptic assessment of toxicological findings, the police investigations and having excluded other causes of death, a lethal GHB‐intoxication following ingestion of 1,4‐BD, can be assumed in this case. Fatal intoxications with 1,4‐BD have seldom been reported due to a very rapid conversion to GHB and, among other things, non‐specific symptoms after ingestion. This case report aims to give an overview to the published of fatal 1,4‐BD‐intoxications and to discuss the problems associated with detection of 1,4‐BD in (postmortem) specimens. [ABSTRACT FROM AUTHOR]

Biochemical analysis of vitreous humor has several forensic applications, including toxicology, estimation of the postmortem interval, and as proxy for select antemortem serum analytes. Estimation of postmortem interval from vitreous humor analytes such as potassium has potential to be a valuable forensic tool for marine mammal strandings, as time of death is essential to provide spatial and temporal context for anthropogenic interactions. The Abaxis VetScan VS2 (VetScan) chemistry analyzer is inexpensive, compact, and requires low sample volume (100 μl), making it ideal for organizations with limited resources and limited samples. This pilot study compared accuracy of the Vetscan on delphinid serum/plasma (n = 7) to the Beckman Coulter AU480, validated the precision of the Vetscan for biochemical analysis of delphinid vitreous humor using the described sample processing protocol, and assessed analyte stability at room temperature in delphinid vitreous humor. Pooled samples (n = 12) of delphinid vitreous humor were serially analyzed and the between‐run and within‐run coefficient of variation of the VetScan was acceptable for most analytes tested but was not for creatinine, total bilirubin, amylase, and alanine aminotransferase. These results demonstrated the precision of the VetScan for the analysis of glucose, albumin, globulin, total protein, urea nitrogen, sodium, potassium, calcium, and phosphorus in delphinid vitreous humor. [ABSTRACT FROM AUTHOR]

Vortioxetine is an antidepressant recently licensed in USA and EU for the treatment of major depressive disorder. Neither fatal case due to overdose nor data about postmortem concentrations on blood or other specimens have been reported. The aims of this study were the development and validation of a method for vortioxetine analysis by Liquid Chromatography Tandem Mass Spectrometry (LC–MS/MS) in postmortem samples and its application in an authentic case. The method was validated and applied on blood, vitreous humor, bile, brain, liver, kidney, and gastric content. After protein precipitation, the supernatant was directly injected into LC–MS/MS. Analysis was carried out by Multiple Reaction Monitoring (MRM) mode. The authentic case concerned a 38 years‐old woman, affected by depression, who was found hanged at home. The method determined an acceptable sensitivity, selectivity, linearity, precision, and accuracy for all matrices. No interference was shown for all matrices. The matrices do not significantly reduce the peak intensity of vortioxetine. No carryover was shown. Toxicological analysis of the authentic case showed vortioxetine in blood (234 ng/ml), vitreous humor (10.5 ng/ml), brain (490 ng/g), lung (479 ng/g), liver (3751 ng/g), kidney (798 ng/g), bile (2267 ng/ml) and gastric content (253 ng/ml). Our case suggests that even at blood concentrations of vortioxetine equal to 234 ng/ml, the subject was able to stage and carry out the hanging. Vortioxetine concentrations found in the other cadaveric samples (biological fluids, organs, and gastric content) may be helpful to evaluate further similar comparable cases. [ABSTRACT FROM AUTHOR]

Synthetic cathinones comprise a large amount of substances present on the dark market, which creates an undeniably worldwide problem and still is posing a threat. A 22‐year‐old man was brought to the Emergency Room from a party, where he had ingested orally 20 g of mephedrone. The man exhibited a disorder of consciousness with no logical verbal contact and dilated pupils. Moreover, a metabolic acidosis was present. The patient died after an hour from an admission to the ER. Blood and vitreous humor collected during an autopsy were analyzed with the use of an ultra‐high‐performance liquid chromatography‐tandem mass spectrometry (UHPLC‐QqQ‐MS/MS) with the use of C18 column in multiple reaction monitoring (MRM) mode. Both biological specimens were prepared using liquid–liquid extraction (LLE) with the use of ethyl acetate and 0.5 M ammonium carbonate water solution (pH 9). The limit of quantification (LOQ) of the method was 0.5 ng/ml in both matrices; precision and accuracy values did not exceed ±15%. Recovery of the method was in the range of 86.1%–102.7%. Determined concentrations of 4‐CMC were 8542 and 9874 ng/ml in blood and vitreous humor, respectively. Other substances present in both biological materials were: atropine, diazepam, lidocaine, and its metabolite norlidocaine, as well as methcathinone and ethyl alcohol. The concentration presented in here described case is the highest ever reported 4‐CMC concentration. Important aspect is also receiving other NPS by recreational users than intended, which lead to accidental poisoning (in presented case user assumed 4‐CMC was 4‐MMC). [ABSTRACT FROM AUTHOR]

Lateral integration and fusion of cartilage tissue interfaces remain significantly challenging and limits success of cartilage tissue engineering (TE) strategies. In this study, self‐assembled vitreous humor (VH) spheroids are fabricated by seeding clinically relevant human articular chondrocytes (hACs) or human mesenchymal stromal cells (hMSCs) in four VH hydrogels with different glycosaminoglycans (GAG) and protein content. Quantitative and qualitative analysis of the VH spheroids revealed that hAC‐VH spheroids are dependent on the initial GAG content of VH hydrogels to achieve successful chondrogenesis. Remarkably, uniform GAG and collagen type II distribution is found in all hMSC‐VH spheroids, independent of the VH donor. HMSC‐VH spheroids are therefore further evaluated for downstream applications by tracking cellular migration, and evaluating neotissue formation at the tissue‐tissue interface of cartilage spheroids 3D‐bioassembled into an in vitro fusion model to asses fusion and integration. hMSC‐VH spheroids enhanced multidirectional cellular migration of both hACs and hMSCs toward the tissue‐tissue interface, and consequently supported dense GAG and collagen type II deposition at the integration region. Ultimately, hMSC‐seeded VH spheroids display successful chondrogenesis and endorse fusion and integration of cartilage tissue interfaces through upregulated cellular migration of clinically relevant cell sources – key elements for clinical translation of cell‐based TE strategies. [ABSTRACT FROM AUTHOR]

A suicide pact is an agreement between people to commit suicide together, which usually takes place at the same time, in the same place, by using the same method. Social media serve as a way of communication between people. Thus, they use such platforms to find potential suicide pact partners. Chloroform, although being regarded to as a slightly forgotten poison, is still linked to homicide and suicide cases. Death due to an acute chloroform ingestion may be a result of central nervous system depression. In this paper, we present application of headspace gas chromatographic method using a dual column/dual flame ionization detector (HS‐GC‐FID/FID) for the determination of chloroform in two fatal intoxication cases, as well as chloroform stability study. Analysis of biological samples revealed chloroform concentrations of 135.8, 16.1, 8.1, and 37.1 µg/ml in blood, urine, vitreous humor, and bile, respectively. Kidney, liver, and muscle specimens contained 119.5, 99.6, and 28.4 µg/g of chloroform, respectively. The results of stability studies indicate the highest decrease of chloroform in room temperature, so it is advised to store samples in a freezer. The addition of sodium fluoride is recommended as in blood samples collected to the test tubes without any preservative agent, the detection of chloroform after 91 days is almost impossible. It is important to emphasize that even old poisons can cause a lot of concerns today, as here described cases are linked to chloroform intoxication, as well as with possible danger which social media bring about nowadays. [ABSTRACT FROM AUTHOR]

The incidence of paraquat poisoning has significantly decreased with the addition of odorizer and emetics to the liquid concentrate. Paraquat poisonings are usually attributed to suicidal and accidental or occupational exposure. Here, we report an unusual fatal case of homicidal paraquat poisoning. An intoxicated, a 37‐year‐old man consumed a mixture of white wine and paraquat prepared by his wife. This resulted in intermittent vomiting, which he attributed to being intoxicated. The man was admitted to the hospital for treatment 3 days later. Due to the lack of knowledge of paraquat exposure, the man did not receive effective treatment and died of respiratory failure 22 days later. High‐performance liquid chromatography‐tandem mass spectrometry (HPLC‐MS/MS) was applied to detect paraquat in 16 postmortem specimens: kidney (1.31 ug/g), urine (0.91 ug/ml), liver (0.62 ug/g), lung (0.39 ug/g), muscle (0.35 ug/g), bile (0.32 ug/ml), heart (0.28 ug/g), brain (0.22 ug/g), pancreas (0.22 ug/g), spleen (0.18 ug/g), cardiac blood (0.15 ug/ml), cerebrospinal fluid (0.14 ug/ml), pericardial effusion (0.12 ug/ml), pleural effusion (0.09 ug/ml), peripheral blood (0.08 ug/ml), and vitreous humor (0.06 ug/ml). The highest concentration of paraquat was detected in the kidney followed by the urine in all tissues and body fluids. At present, although the cases of paraquat poisoning have decreased, the high mortality rate resulting from its irreversible lung damage and respiratory failure makes paraquat poisoning, especially occult paraquat poisoning, still needs to be carefully identified in forensic practice and clinical diagnosis. [ABSTRACT FROM AUTHOR]

The constant emergence of novel psychoactive substances is troubling to both public health officials and legislators. Additionally, sufficient data collection for each new compound can take months up to years. Flualprazolam, a triazolobenzodiazepine, quickly garnered attention as a sedative drug that likely expresses adverse reactions similarly to alprazolam. This study focuses on the distribution of flualprazolam in multiple common postmortem matrices. Central blood, vitreous humor, liver homogenate, brain homogenate, gastric contents, and urine samples from death investigation cases were quantitated when available. Samples were screened with liquid chromatography quadrupole time‐of‐flight with limit of detection set at 4 ng/ml and quantitated on liquid chromatography tandem mass spectrometry, with concentration range from 4 to 256 ng/ml. From August 2018 to September 2020, 24 central blood samples were quantitated for flualprazolam. Central bloods of 22 cases had concentrations above the limit of quantitation. The average flualprazolam central blood concentration was 16.3 ng/ml with a median of 9.95 ng/ml (4.24–48.0). Additional analyses for unconjugated flualprazolam were performed on at a total of 15 urine samples (x¯ = 14.4, 4.07–36.1 ng/ml), 23 brain homogenates (x¯ = 23.2, 3.99–69.3 ng/g), 23 liver homogenates (x¯ = 50.7, 13.6–156 ng/g), five vitreous humor samples (x¯ = 7.70, 4.03–12 ng/ml), and 12 gastric contents samples (x¯ = 0.36, 0.02–2.51 mg). The cause of death for 13 of the 24 cases listed flualprazolam as a contributing factor of death. [ABSTRACT FROM AUTHOR]

The paper presents a method for the determination of methadone, EDDP, and EMDP in postmortem biological materials using liquid‐liquid extraction with ethyl acetate (pH9) and UHPLC‐MS/MS technique. Methadone‐d9 and EDDP‐d3 were used as the internal standards. The method validation results for blood and urine were as follows: linearity: 0.5–1000 ng/ml; R2 > 0.9993 for methadone, EDDP and R2 > 0.9944 for EMDP. Intra‐ and inter‐day precision: 0.1%–7.5% and 0.3%–8.6%, respectively; intra‐ and inter‐day accuracy: −11.8% to 13.9% and −9.3 to 14.8%, respectively; recovery: 91.5%–123.0%; matrix effect: 83.5%–123.9%. This study also describes 18 postmortem cases, where methadone concentrations ranged 2.3–1180 ng/ml in blood (n = 17), from 11.0 to >10,000 ng/ml in urine (n = 13) and 135.2–409.0 in vitreous humor (VH, n = 3). EDDP concentrations ranged from not detectable to 180 ng/mL in blood, from 42.4 to >10,000 ng/ml in urine and 18.3–36.5 in VH. EMDP concentrations were found in four cases in blood from below LLOQ to 1.8 ng/ml and in seven cases in urine, ranged 2.1–243.0 ng/ml. EMDP was not detected in VH samples. The EDDP/methadone ratios and blood/urine ratios for methadone and EDDP in EMDP‐positive and negative cases were performed. The paper presents mass spectra of other methadone metabolites, than EDDP and EMDP (ring hydroxylated methadone, ring hydroxylated EDDP, ring hydroxylated EMDP, methadol, and DDP). Simultaneous determination of methadone and its metabolites in order to unequivocally interpret the results of toxicological tests seems to be useful in cases related to prescription/illicit use of methadone. [ABSTRACT FROM AUTHOR]

Transient receptor potential vanilloid 4 (TRPV4) channels are mechanosensitive ion channels that regulate systemic endothelial cell (EC) functions such as vasodilation, permeability, and angiogenesis. TRPV4 is expressed in retinal ganglion cells, Müller glia, pigment epithelium, microvascular ECs, and modulates cell volume regulation, calcium homeostasis, and survival. TRPV4‐mediated physiological or pathological retinal angiogenesis remains poorly understood. Here, we demonstrate that TRPV4 is expressed, functional, and mechanosensitive in retinal ECs. The genetic deletion of TRPV4 did not affect postnatal developmental angiogenesis but increased pathological neovascularization in response to oxygen‐induced retinopathy (OIR). Retinal vessels from TRPV4 knockout mice subjected to OIR exhibited neovascular tufts that projected into the vitreous humor and displayed reduced pericyte coverage compared with wild‐type mice. These results suggest that TRPV4 is a regulator of retinal angiogenesis, its deletion augments pathological retinal angiogenesis, and that TRPV4 could be a novel target for the development of therapies against neovascular ocular diseases. [ABSTRACT FROM AUTHOR]

Background Information: Leukocytes migrate in an amoeboid fashion while patrolling our organism in the search for infection or tissue damage. Their capacity to migrate has been proven integrin independent, however, non‐specific adhesion or confinement remain a requisite in current models of cell migration. This idea has been challenged twice within the last decade with human neutrophils and effector T lymphocytes, which were shown to migrate in free suspension, a phenomenon termed swimming. While the relevance of leukocyte swimming in vivo remains under judgment, a growing amount of clinical evidence demonstrates that leukocytes are indeed found in liquid‐filled body cavities, occasionally with phagocyted pathogens, such as in the amniotic fluid, the cerebrospinal fluid (CSF), or the eye vitreous and aqueous humor. Results: We studied in vitro swimming of primary human neutrophils in the presence of live bacteria, in 2 and 3 dimensions. We show that swimming neutrophils perform phagocytosis of bacteria in suspension. By micropatterning live bacteria on a substrate with an optical technique, we further prove that they use chemotaxis to swim towards their targets. Moreover, we provide evidence that neutrophil navigation can alternate between adherent and non‐adherent modes. Conclusions: Our results suggest that human neutrophils do not rely on adhesion to carry out their functions, supporting a versatile phagocytic function adaptable to the various environmental conditions encountered in vivo, as already suggested by clinical data. Significance: We verified a claim stated 10 years ago and never reproduced, on the capacity of human neutrophils to swim and perform swimming chemotaxis. We further extended those results to prove that swimming neutrophils can phagocytise bacteria, disregarding adhesion nor confinement as a requisite for accomplishing their function, which differs with current paradigms of leukocyte migration. [ABSTRACT FROM AUTHOR]

We present results of our study on the stability of 4‐chloromethcathinone (4‐CMC) in authentic postmortem peripheral blood and vitreous humor samples. The stability of 4‐CMC was determined in postmortem blood samples (for a period of 90 days) and vitreous humor (30 days) at three different temperatures: −15°C, +4°C, and + 23°C. The analyses were carried out using ultra‐high‐performance liquid chromatography coupled with triple‐quadrupole tandem mass spectrometry (UHPLC‐QqQ‐MS/MS). In both materials, the lowest 4‐CMC stability was demonstrated at room temperature. The blood samples stored in a freezer (−15°C) showed stability for the entire study period (90 days), while in the case of the vitreous humor sample stored at the same temperature the concentration of the substance decreased by 53% after 30 days. The study carried out in authentic postmortem blood and vitreous humor samples confirms the previous reports of 4‐CMC instability in biological material. Authors suggest that the biological material should be stored frozen until analyses are carried out as soon as possible after collection of the material. [ABSTRACT FROM AUTHOR]

A retrospective, cross‐sectional analysis of vitreous beta‐hydroxybutyrate (BHB) on 967 forensic cases over a two‐year period was conducted. Cases were sorted into six categories of death: (i) sudden traumatic/non‐natural (ST), (ii) sudden natural (SN), (iii) prolonged traumatic/non‐natural (PT), (iv) prolonged natural (PN), (v) diabetic ketoacidosis (DKA), and (vi) alcoholic ketoacidosis (AKA). The mean BHB for all cases was 1.67 mmol/L (17.4 mg/dL; range: 0.11–18.02 mmol/L). The numbers of DKA, AKA, PN, PT, SN, and ST deaths were 21, 5, 155, 258, 275, and 253, respectively. Their mean vitreous BHBs were as follows: 11.04 mmol/L (DKA), 8.88 mmol/L (AKA), 1.56 mmol/L (PN), 1.55 mmol/L (PT), 1.26 mmol/L (SN), and 1.38 mmol/L (ST). There was a statistically significant difference between the mean BHBs of the PN and SN death groups (p < 0.001), as well as between those of the PT and ST death groups (p = 0.004). Given the overlapping ranges seen between the prolonged and sudden death groups, the identified differences did not hold clinical significance. In addition, we sought to determine a threshold value for vitreous BHB to definitely diagnose cases of ketoacidosis. BHB threshold concentrations between 2.5 and 5 mmol/L produced sensitivities >92% and specificities >96%. A receiver operator characteristic curve found 3.43 mmol/L to be the optimal cutoff value, demonstrating a specificity of 98.3% and a sensitivity of 96.2%. [ABSTRACT FROM AUTHOR]

Aim. To analyze the levels of B-cell-produced antibodies in the vitreous humor of patients with or without diabetic retinopathy (DR) both qualitatively and quantitatively. Methods. A total of 52 type 2 diabetes mellitus (T2DM) with DR patients and 52 control subjects without diabetes mellitus or inflammatory diseases were included in this prospective study. The levels of immunoglobulin (Ig)A, IgM, and IgG subtypes were measured using a magnetic color-bead-based multiplex assay. Results. The concentrations of IgA, IgM, and total antibodies in the DR group were significantly higher than those in the control group (all p < 0.001), but there was no significant difference in the 4 IgG subtypes between the two groups after Bonferroni correction. Pearson's correlation analysis revealed low negative correlations between levels of antibodies (IgA, IgM) and estimated glomerular filtration rate (eGFR, r = − 0.443 , r = − 0.377 , respectively, both p < 0.05). Furthermore, multiple linear regression analysis yielded three equations to predict the concentrations of IgA, IgM, and total antibodies in the vitreous humor according to eGFR and other clinical variables (r = 0.542 , r = 0.461 , and r = 0.312 , respectively, all p < 0.05). Conclusion. Increased levels of IgA, IgM, and total antibodies produced by B cells were observed in the vitreous humor of T2DM patients with DR. There were low negative correlations between levels of antibodies (IgA, IgM) and eGFR. [ABSTRACT FROM AUTHOR]

Only limited data exist concerning the utility of complementary specimens in heroin‐related deaths. As such, this report employed a validated LC‐MS‐MS method to quantify 6‐monoacetylmorphine (6‐MAM), 6‐acetylcodeine (6‐AC), and their metabolites morphine and codeine in blood with (BN) and without preservative (B) and the additional unpreserved specimens of vitreous humor, urine, stomach contents, and bile from 20 postmortem cases in which heroin was the primary cause of death. The median concentration of 6‐MAM in BN was 0.011 mg/L, B was 0.008 mg/L, urine was 0.186 mg/L, vitreous humor was 0.022 mg/L, stomach contents was 0.147 mg/L, and bile was 0.012 mg/L. Only one case was found to be positive for 6‐AC in B (case 6, 0.002 mg/L), and the median concentration of 6‐AC was 0.002 mg/L in BN, 0.012 mg/L in urine, 0.003 mg/L in vitreous humor, 0.057 mg/L in stomach contents, and 0.004 mg/L in bile. These findings present new information on the distribution of these analytes in complementary matrices and support their inclusion for accurately determining the role of heroin in opioid‐related deaths. [ABSTRACT FROM AUTHOR]

Urea, uric acid, and creatinine have been demonstrated to be relatively stable in postmortem blood (BL), thus being useful for diagnostic purposes. However, no studies have explored their levels in BL, vitreous humor (VH), and synovial fluid (SF) concurrently. Therefore, we measured and compared their levels in these fluids. We also determined the effects of various factors on their levels. The results indicated that BL urea, uric acid, and creatinine levels were significantly higher than VH and SF levels. VH and SF urea levels and SF creatinine levels had a strong correlation with BL urea and creatinine levels, respectively. BL creatinine levels were higher in men than in women. BL and SF creatinine levels were negatively correlated with age. SF uric acid and BL, VH, and SF creatinine levels exhibited a positive correlation with weight. Only VH creatinine levels were positively correlated with body mass index. None of urea, uric acid, and creatinine levels were correlated with postmortem interval. [ABSTRACT FROM AUTHOR]

Urea, uric acid, and creatinine have been demonstrated to be relatively stable in postmortem blood (BL), thus being useful for diagnostic purposes. However, no studies have explored their levels in BL, vitreous humor (VH), and synovial fluid (SF) concurrently. Therefore, we measured and compared their levels in these fluids. We also determined the effects of various factors on their levels. The results indicated that BL urea, uric acid, and creatinine levels were significantly higher than VH and SF levels. VH and SF urea levels and SF creatinine levels had a strong correlation with BL urea and creatinine levels, respectively. BL creatinine levels were higher in men than in women. BL and SF creatinine levels were negatively correlated with age. SF uric acid and BL, VH, and SF creatinine levels exhibited a positive correlation with weight. Only VH creatinine levels were positively correlated with body mass index. None of urea, uric acid, and creatinine levels were correlated with postmortem interval. [ABSTRACT FROM AUTHOR]

Fatalities implicating psychedelic mushrooms are not a common clinical situation in everyday forensic medicine. Despite classification as an illegal drug in many countries, psilocybin mushrooms have the reputation of being safe. We report the case of a young man who jumped from a second story balcony under the influence of psilocybin mushrooms. The psilocin assay was performed by gas chromatography coupled to an electron‐impact ionization time‐of‐flight detector (GC‐EI‐TOF) after solid‐phase extraction. Total psilocin was quantified in peripheral and cardiac blood as 60 and 67 ng/mL, respectively, and in urine (2230 ng/mL), bile (3102 ng/mL), and vitreous humor (57 ng/mL). This case report and review of literature highlights the danger of psilocybin mushrooms. Isolated use of psilocybin mushrooms by a regular consumer without psychiatric history, even under "safe" circumstances, can lead to a fatal outcome. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Abstract: Aging is a phenomenon that is associated with profound medical implications. Idiopathic epiretinal membrane (iEMR) and macular hole (MH) are the major vision‐threatening vitreoretinal diseases affecting millions of aging people globally, making these conditions an important public health issue. iERM is characterized by fibrous tissue developing on the surface of the macula, which leads to biomechanical and biochemical macular damage. MH is a small breakage in the macula and is associated with many ocular conditions. Although several individual factors and pathways are suggested, a systems pathology level understanding of the molecular mechanisms underlying these disorders is lacking. Therefore, we performed mass spectrometry‐based label‐free quantitative proteomics analysis of the vitreous proteomes from patients with iERM and MH to identify the key proteins, as well as the multiple interconnected biochemical pathways, contributing to the development of these diseases. We identified a total of 1,014 unique proteins, many of which are linked to inflammation and the complement cascade, revealing the inflammation processes in retinal diseases. Additionally, we detected a profound difference in the proteomes of iEMR and MH compared to those of diabetic retinopathy with macular edema and rhegmatogenous retinal detachment. A large number of neuronal proteins were present at higher levels in the iERM and MH vitreous, including neuronal adhesion molecules, nervous system development proteins, and signaling molecules, pointing toward the important role of neurodegenerative component in the pathogenesis of age‐related vitreoretinal diseases. Despite them having marked similarities, several unique vitreous proteins were identified in both iERM and MH, from which candidate targets for new diagnostic and therapeutic approaches can be provided. [ABSTRACT FROM AUTHOR]

Abstract: A method to determine postmortem interval (PMI) based on environmental temperature and the concentrations of vitreous humor (VH) molecules were explored. Rabbit carcasses were placed in a chamber at 5, 15, 25, or 35°C, and 80–100 μL of VH was collected with the double‐eye alternating micro‐sampling method every 12 h. A Roche DPPI biochemical analyzer was used to measure the concentrations of six substances in VH samples. The interpolation function model and mixed‐effect model were employed for data fitting to establish equations for PMI estimation. The concentrations of K+, P, Mg2+, creatinine (CRE), and urea nitrogen (UN) exhibited an upward trend with increasing PMI in all temperature groups, while the concentration of Ca2+ showed a downward trend. Validation results using K+ and Mg2+ ions revealed that the mixed‐effect model provided a better estimation than the interpolation function model using the data from our experiment. However, both models were able to estimate PMI using temperature and VH molecule concentrations. [ABSTRACT FROM AUTHOR]

Abstract: Hydrogels are made from natural or synthetic polymers and, currently, they have many biomedical applications. In this work, the conditions for obtaining a hydrogel with similar physicochemical characteristics to the vitreous humor were defined using polyvinyl alcohol (PVA) and glutaraldehyde (GLUT) as cross‐linker. The concentration of PVA and GLUT were modified, and their effect was analyzed in terms of the refractive index, density, and dynamic viscosity. The hydrogel which was obtained using 3.98% (w/V) of PVA, 3.13 mL (1.57 g) of GLUT in 100 mL, and the initial pH of 7.2 showed similar characteristics to the vitreous humor (density = 1.0174 ± 0.0050 g mL−1, dynamic viscosity = 3.7425 ± 0.1800 mPa s and refractive index = 1.3410 ± 0.0010). The hydrogels were further investigated by rheological measurements, infrared spectroscopy, differential scanning calorimetry, X‐ray diffraction and determination of swelling degree. The reticulation with GLUT promoted an increase in viscosity and glass transition temperature. On the other hand, it stimulated a decrease in the swelling degree, crystallinity, melting temperature, and intensity of the band related to the ‐OH bond, compared with the PVA without reticulation. The reticulated hydrogel displayed Newtonian behavior and a higher apparent viscosity than the PVA. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1558–1566, 2018. [ABSTRACT FROM AUTHOR]

Determination of time since death (TSD) plays very important role in forensic examination as it narrows down field of suspects and aids in deceased identification. This study utilizes the fluorescence property of vitreous humor (VH) tryptophan to determine TSD using o-phthalaldehyde (OPA). The detection limit of these fluorometric studies was found to be 8 ppb indicating sensitivity and high accuracy in TSD determination. The study was performed on selected 76 cadaver with known TSD ranging from 3 to 90 h. Excellent correlation between VH tryptophan and TSD was obtained with a coefficient of correlation R2 = 0.9590. Results showed statistically significant increase in vitreous tryptophan with TSD up to 90 h, and the proposed method was efficaciously applied for prediction of TSD as no systematic error exist. The regression equation obtained from the study is [Trp] = 2.21 + 2.98 * TSD. [ABSTRACT FROM AUTHOR]

Background and objective Conventional methods to treat intraocular diseases are invasive or associated with adverse effects. A minimally invasive means of sustained-release drug delivery to the vitreous is required. This study evaluated a novel device for subtenon drug delivery to the vitreous, relative to a single subconjunctival injection. Methods Sixty adult New Zealand White rabbits were randomly assigned to receive demethylvancomycin ( DMV) by continuous subtenon delivery with the flow rate of 0.1 ml/hr for 24 hr, or as a single 0.3 ml subconjunctival injection in the right eyes. Rabbits were killed in subgroups of six at 1, 3, 6, 12 and 24 hr. The DMV concentration of the vitreous humour of the right eye was analysed by high-performance liquid chromatography. Results Overall, the vitreous DMV concentration of the subtenon group was significantly higher than that of the subconjunctival group ( F = 25.928, p = 0.001). The DMV concentration of the subtenon group was also significantly higher than that of the subconjunctival group at 3, 6, 12 and 24 hr ( t = 2.457, 5.064, 3.085, 4.207; p = 0.04, 0.01, 0.018, 0.004, respectively). In the subtenon group, the DMV concentration reached maximum (2.41 ± 0.67 μg/ml) at 6 hr, and at 24 hr was 2.37 ± 1.23 μg/ml. In the subconjunctival group, the DMV concentration reached maximum (0.48 ± 0.27 μg/ml) at 1 hr and declined to 0.09 ± 0.05 μg/ml at 24 hr. Conclusion Subtenon application with this novel minimally invasive design is an effective method for delivering an appropriate drug to the vitreous in a sustained and controllable amount. [ABSTRACT FROM AUTHOR]

In forensic diagnosis, postmortem blood glucose is known to be susceptible to change after death. However, the 1,5-anhydroglucitol (1,5- AG) concentrations in plasma and cerebrospinal fluid ( CSF) reflect the mean blood glucose level for a short period of time. In this study, we compared the postmortem 1,5- AG concentrations in vitreous humor and CSF in 47 subjects to evaluate the utility of this concentration in the vitreous humor for forensic diagnosis. The postmortem 1,5- AG concentrations in vitreous humor (mean± SD: 20.2 ± 8.7 μg/ mL) and CSF (16.8 ± 8.7 μg/ mL) did not differ significantly and showed a strong correlation ( r2 = 0.87, p < 0.01). These results suggest that the vitreous humor 1,5- AG concentration provides useful information on the antemortem blood glucose level, in addition to the HbA1c value and the CSF 1,5- AG concentration. [ABSTRACT FROM AUTHOR]

Research into maximizing the speed, precision, and reliability of estimating the postmortem interval ( PMI) has been a recurring object of investigation and methodologies based on the vitreous humor ( VH) have provided good results. However, contamination from causes not readily apparent, such as blood, can occur, and thus lead not only to an erroneous estimation of PMI, but also interfere with the correct identification of other substances in the VH. We have developed a flow cytometry method which quantifies blood contamination and is able to detect erythrocytes in 1:750,000 dilution of contaminated VH which affects the results of hypoxanthine. It is an improvement on the previous more complex mass spectrometry method, being faster, more sensitive, and readily available. As such, it could be proposed for the rapid screening of appropriate samples by detecting and eliminating blood contaminated samples from PMI estimation. [ABSTRACT FROM AUTHOR]

The death of a person as a reaction to the death of another is known as Philemon and Baucis death and may represent a difficult challenge for pathologists, especially due to the decompositional changes that often characterized these situations. In this article, we describe two cases of Philemon and Baucis deaths, the first concerning a married couple and the second concerning a father and son. Postmortem investigations including radiology and biochemistry were performed. Based on the results of all investigations, deaths were attributed to natural causes. Third-party involvement could be excluded in both situations. In one case, biochemical analysis results revealed potentially contributing causes of death. The reported cases emphasize the importance of correlating findings from different postmortem investigations to identify causes of death, precipitating conditions and predisposing disorders, thus allowing the conclusion of natural death to be reached and third-party involvement to be excluded. [ABSTRACT FROM AUTHOR]

The use of magnesium as a parameter to estimate the time of death is controversial. In 32 traumatic deaths with known postmortem intervals ( PMIs), small quantities of vitreous humor ( VH) were sampled repetitively every 3 h until 24 h postmortem. The bodies were kept at the constant ambient temperature of 20°C (68°F). The concentrations of magnesium were in the range of 0.47-1.15 mM. A statistically significant correlation of the concentration of magnesium with the PMI was observed ( r = 0.453, p < 0.01), but with small predictive value-coefficient of variation for regression was 45.5%; the average of the paired differences between the estimated and actual PMIs was 5.24 + 3.19 h. Although useful results might be expected due to the large transmembrane gradient for magnesium, the results of this study strongly disprove the usefulness of measuring magnesium in VH to estimate the time of death. [ABSTRACT FROM AUTHOR]

The concentrations of 3-beta-hydroxybutyrate (3HB) in femoral blood, urine, vitreous humor as well as pericardial and cerebrospinal fluids were retrospectively examined in a series of medico-legal autopsies, which included cases of diabetic ketoacidosis, hypothermia fatalities without ethanol in blood, bodies presenting mild decompositional changes, and sudden deaths in chronic alcoholics. Similar increases in 3HB concentrations were observed in blood, vitreous, and pericardial fluid, irrespective of the cause of death, suggesting that pericardial fluid and vitreous can both be used as alternatives to blood for postmortem 3HB determination. Urine 3HB levels were higher than blood values in most cases. Cerebrospinal fluid 3HB levels were generally lower than concentrations in blood and proved to be diagnostic of underlying metabolic disturbances only when significant increases occurred. [ABSTRACT FROM AUTHOR]

ABSTRACT A simple method is presented for the simultaneous determination of morphine, 6-acetylmorphine, codeine, cocaine, benzoylecgonine, cocaethylene, methadone and 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) in vitreous humor by high-performance liquid chromatography with photodiode array detector after solid-phase extraction with Oasis® HLB cartridges and dichloromethane as eluent. The chromatographic process was carried out using an XTerra® RP8 column (250 × 4.6 mm i.d., 5 µm particle size) and a mobile phase composed of acetonitrile and pH 6.5 phosphate buffer in gradient mode. A linear response from the detector was obtained within the concentration range of 0.1-4 µg ml−1, with correlation coefficients higher than 0.99. The limits of detection were lower than 30 ng ml−1 for all the drugs studied, the coefficients of variation fluctuated between 0.1 and 12.4%, and the average recoveries were higher than 78% for all the drugs except for EDDP, with a value of 66.4%. Finally, the proposed method was applied to 15 vitreous humor samples coming from individuals who had died from opiate and/or cocaine overdose, showing consumption of cocaine in 14 cases, methadone in five cases and heroin in three cases. Average concentrations of 0.30 µg ml−1 for morphine, 0.24 µg ml−1 for 6-acetylmorphine, 0.10 µg ml−1 for codeine, 0.81 µg ml−1 for cocaine, 1.26 µg ml−1 for benzoylecgonine, 0.15 µg ml−1 for cocaethylene, 0.11 µg ml−1 for methadone and 0.68 µg ml−1 for EDDP were obtained. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Analytical solution of dispersion in rapidly oscillating flows becomes infeasible in complex geometries. Simulation over long durations can be prohibitively expensive when there is a wide separation between the oscillation and dispersion time scales. Here, we present a methodology based on an implicit envelope-tracking scheme coupled with telescopic projections. A test problem, with a known analytical solution, was simulated, and the effect of Péclet number on the dispersivities was investigated. The solution was unaffected by the time steps for telescopic projections while increasing Péclet numbers introduced errors. The error was found to decrease with mesh refinement, but a small inherent error was observed. The method was also applied to a practical problem of interest to us: drug dispersion due to sloshing in the vitreous humor of the eye. Relative to single-scale solution, the method, when applied to the vitreous sloshing problem, produced speedup values of up to 100. © 2011 American Institute of Chemical Engineers AIChE J, 2012 [ABSTRACT FROM AUTHOR]

Vitreous body is an intraocular structure, origin of diverse pathologies, but is also the place where cells and inflammatory mediators are released coming from several pathologic processes. These inflammatory reactions can happen in any other ocular location like choroid, retina, optic nerve, or ciliary body and vitreous humor constitutes a stagnant reservoir for these resulting substances and debris. Through the recent techniques of vitreous collecting, handling, and analysis, increasingly more sophisticated and with fewer complications, cellularity and molecules in the vitreous of challenging pathologies for the ophthalmologist can now be studied. Themost usefulness for vitreous diagnosis would be the masquerade syndromes, and the best exponent in this group is the primary vitreoretinal lymphoma (PVRL), in which cytology and an IL-10/IL-6 ratio more than 1 is fundamental for the diagnosis. [ABSTRACT FROM AUTHOR]

The human vitreous humour (VH) is a transparent, highly hydrated gel, which occupies the posterior segment of the eye between the lens and the retina. Physiological and pathological conditions of the retina are reflected in the protein composition of the VH, which can be sampled as part of routine surgical procedures. Historically, many studies have investigated levels of individual proteins in VH from healthy and diseased eyes. In the last decade, proteomics analyses have been performed to characterise the proteome of the human VH and explore networks of functionally related proteins, providing insight into the aetiology of diabetic retinopathy and proliferative vitreoretinopathy. Recent proteomic studies on the VH from animal models of autoimmune uveitis have identified new signalling pathways associated to autoimmune triggers and intravitreal inflammation. This paper aims to guide biological scientists through the different proteomic techniques that have been used to analyse the VH and present future perspectives for the study of intravitreal inflammation using proteomic analyses. [ABSTRACT FROM AUTHOR]

A bstract Background: To determine whether the status of a macular hole can be determined by spectral-domain optical coherence tomography in gas-filled eyes. Design: Prospective study, university hospital setting. Participants: Twenty-six eyes with a macular hole, seven eyes with a macular hole retinal detachment and four eyes with a macular hole and myopic traction maculopathy underwent vitreous surgery. Methods: The macular area was examined by spectral-domain optical coherence tomography (OCT-4000) on postoperative days 1, 3, 7 and 30. Main Outcome Measures: Detection of macular hole closure. Results: The status of macular hole was able to be assessed in 24 eyes (92%) on postoperative day 1 and 23 were closed. The condition of the macular hole could not be determined in the other two eyes with a lower volume of gas (≤60%). The macular hole of seven eyes could be seen only when the patients looked upward or downward ( P = 0.009). The 11 eyes with a macular hole retinal detachment or a myopic traction maculopathy had a posterior staphyloma, and the macular hole was visible in four eyes on day 1 ( P = 0.001). When a closure of the macular hole was detected on day 1, the macular hole remained closed in all of these eyes on day 30. Conclusions: The status of a macular hole can be determined by spectral-domain optical coherence tomography on postoperative day 1 even in gas-filled eyes. The visibility depends on the volume of intravitreal gas and the absence of a posterior staphyloma. [ABSTRACT FROM AUTHOR]

This work presents a study which aimed to quantify the intravitreally-injected vancomycin antibiotic using dispersive Raman spectroscopy and Partial Least Squares multivariate calibration. Eyes of New Zealand rabbits were injected with 5.0 mg vancomycin at different time intervals (8, 24 and 48 h groups). Distilled water was injected into the eyes of rabbits in the control group. The vitreous was then removed from each eyeball, placed into a quartz cuvette and submitted for dispersive Raman spectroscopy. The Raman equipment used a laser (80 mW, 830 nm), an imaging spectrograph and a CCD camera with exposure time of 50 s. A calibration curve was developed using the PLS method with vancomycin diluted in water in the range of 1.0-8.0 mg/ml. The spectrum of vancomycin was present in bands at the positions of C=C, amide I, CH3, amide III and vibrations of the carbon chain (C-C, aromatic ring breathing and C-O-C). The spectra of the injected vitreous bodies showed weak bands which were correlated with the pure drug. The PLS calibration model had a standard error of prediction of 0.8 mg/ml using one latent variable. The PLS showed changes in the predicted concentrations of the injected vitreous bodies depending on the time of injection, with an amount near zero for the water-injected group and ranging between 2 and 3 mg/ml for the drug-injected groups. Raman spectroscopy could be employed in the quantitative evaluation of intravitreally-injected vancomycin in future in vivo applications. [ABSTRACT FROM AUTHOR]

Scrapie, a transmissible spongiform encephalopathy (TSE) occurring naturally in sheep, characteristically shows a severe retinopathy that is well developed in the terminal phases of the disease. In this study, we set out to demonstrate similar retinal changes in our ruminant spiroplasmosis TSE model. The eyes from deer, sheep, and goats that were inoculated intracranially with the laboratory strain of spiroplasma (suckling mouse cataract [SMCA] strain of Spiroplasma mirum) or with Spiroplasma sp. isolated from the brains affected with scrapie or with chronic wasting disease were examined by light microscopy for pathologic changes and by immunocytochemistry for distribution of spiroplasma antigen. The eyes were also obtained from a research flock of sheep with terminal scrapie, from which the intraocular tissues were submitted aseptically for culture assay in M1D broth or as explants on bovine corneal endothelia (BCE). The eyes from the spiroplasmosis ruminant models showed retinopathy remarkably similar to eye lesions seen in sheep with scrapie. The spiroplasma antigen accrued in the ruminant model eye tissues, particularly in the retina, the vitreous humor, and the corneal endothelia. A Spiroplasma sp. grew out of the scrapie-affected eyes both in the M1D broth and in the BCE cultures but did not expand. These new spiroplasma isolates differed immunologically from SMCA. These data showed a clear association of spiroplasma with scrapie suggesting that these bacteria have a role in the pathogenesis of TSE and that the eye should be a research focus for future studies of TSE. [ABSTRACT FROM AUTHOR]

Study Objective. To determine whether daptomycin has the potential to be an effective alternative treatment to vancomycin for methicillin-resistant Staphylococcus aureus (MRSA) endogenous endophthalmitis by measuring daptomycin penetration into the vitreous humor. Design. Laboratory analysis of serum and intravitreal fluids to quantify the ratio between vitreous humor and serum daptomycin concentrations. Setting. Critical care unit in a university-affiliated tertiary care medical center. Patient. A 53-year-old woman treated with intravenous daptomycin for MRSA bacteremia, endophthalmitis, and pericarditis. Measurements and Main Results. After the first dose of intravenous daptomycin 10 mg/kg was administered to the patient, serum and intravitreal fluids were analyzed by using high-performance liquid chromatography to determine daptomycin concentrations; pericardial fluid was also analyzed to determine whether adequate levels were present in actively infected tissue. A vitreous concentration of approximately 28% of the serum concentration was achieved. Although therapeutic efficacy could not be assessed in the absence of intraocular cultures, the presence of adequate drug concentrations in the vitreous humor is promising. Ophthalmic infections caused by resistant isolates continue to increase, and effective alternatives to vancomycin, the standard of care, are needed. For endogenous endophthalmitis, these alternative therapies will need to reach therapeutic concentrations in the vitreous humor and adequately penetrate the terminal source of infection. In this analysis, the intravitreal concentration of daptomycin was comparable to concentrations previously reported with vancomycin; thus daptomcyin may be an attractive option when vancomycin therapy fails or is contraindicated. To our knowledge, this is the first report of intravitreal daptomycin concentrations measured in a patient receiving intravenous daptomycin. Conclusion. Adequate concentrations of daptomycm were achieved in the vitreous fluid after a single systemic dose of the drug. Daptomycin may be an effective alternative to vancomycin in patients with ophthalmic infections. Future clinical studies comparing daptomycin with vancomycin in this clinical setting are warranted. [ABSTRACT FROM AUTHOR]