Vasopressin in Sepsis and Other Shock States: State of the Art.

This review of the use of vasopressin aims to be comprehensive and highly practical, based on the available scientific evidence and our extensive clinical experience with the drug. It summarizes controversies about vasopressin use in septic shock and other vasodilatory states. Vasopressin is a natural hormone with powerful vasoconstrictive effects and is responsible for the regulation of plasma osmolality by maintaining fluid homeostasis. Septic shock is defined by the need for vasopressors to correct hypotension and lactic acidosis secondary to infection, with a high mortality rate. The Surviving Sepsis Campaign guidelines recommend vasopressin as a second-line vasopressor, added to norepinephrine. However, these guidelines do not address specific debates surrounding the use of vasopressin in real-world clinical practice.

Association between use of enhanced recovery after surgery protocols and postoperative complications after gastric surgery for cancer (POWER 4): a nationwide, prospective multicentre study / Asociación entre el uso de protocolos de recuperación intensificada y complicaciones postoperatorias tras cirugía gástrica por cáncer (POWER 4): estudio nacional, prospective multicéntrico

Introduction: The effectiveness of the Enhanced Recovery After Surgery (ERAS) protocols in gastric cancer surgery remains controversial. Methods: Multicentre prospective cohort study of adult patients undergoing surgery for gastric cancer. Adherence with 22 individual components of ERAS pathways were assessed in all patients, regardless of whether they were treated in a self-designed ERAS centre. Each centre had a three-month recruitment period between October 2019 and September 2020. The primary outcome was moderate-to-severe postoperative complications within 30 days after surgery. Secondary outcomes were overall postoperative complications, adherence to the ERAS pathway, 30 day-mortality and hospital length of stay (LOS). Results: A total of 743 patients in 72 Spanish hospitals were included, 211 of them (28.4 %) from self-declared ERAS centres. A total of 245 patients (33 %) experienced postoperative complications, graded as moderate-to-severe complications in 172 patients (23.1 %). There were no differences in the incidence of moderate-to-severe complications (22.3% vs. 23.5%; OR, 0.92 (95% CI, 0.59 to 1.41); P = 0.068), or overall postoperative complications between the self-declared ERAS and non-ERAS groups (33.6% vs. 32.7%; OR, 1.05 (95 % CI, 0.70 to 1.56); P = 0.825). The overall rate of adherence to the ERAS pathway was 52% [IQR 45 to 60]. There were no differences in postoperative outcomes between higher (Q1, > 60 %) and lower (Q4, ≤ 45 %) ERAS adherence quartiles. Conclusions: Neither the partial application of perioperative ERAS measures nor treatment in self-designated ERAS centres improved postoperative outcomes in patients undergoing gastric surgery for cancer. (AU)

Introducción: La efectividad de los protocolos de recuperación intensificada o ERAS en la cirugía del cáncer gástrico sigue siendo controvertida. Métodos: Estudio de cohortes prospectivo multicéntrico de pacientes intervenidos de cáncer gástrico. Se evaluó la adherencia a 22 elementos ERAS en todos los pacientes, independientemente de la existencia de un protocolo ERAS. Cada centro tuvo un período de reclutamiento de tres meses, con un seguimiento de 30 días. La medida de resultado primario fue el numero de complicaciones posoperatorias moderadas a graves. Las medidas de resultado secundarias fueron el número total de complicaciones, la adherencia a los elementos ERAS, la mortalidad y la estancia. Resultados: Se incluyeron 743 pacientes en 72 hospitales, 211 (28,4 %) en centros ERAS. 245 pacientes (33 %) experimentaron complicaciones posoperatorias, moderadas o graves en 172 (23,1 %). No hubo diferencias en la incidencia de complicaciones moderadas a graves (22,3 % vs. 23,5 %; OR, 0,92 (IC 95 %, 0,59 a 1,41); P = 0,068), o complicaciones posoperatorias totales entre los centros ERAS y no ERAS (33,6 % vs. 32,7 %; OR, 1,05 (IC 95 %, 0,70 a 1,56); P = 0,825). La adherencia a los elementos ERAS fue del 52% [IQR 45 a 60]. No hubo diferencias entre los cuartiles de cumplimiento ERAS más alto (Q1, > 60 %) y más bajo (Q4, ≤ 45 %). Conclusiones: Ni la aplicación parcial de medidas ERAS ni el tratamiento en centros ERAS mejoraron los resultados en pacientes sometidos a cirugía gástrica por cáncer. (AU)

Association between use of enhanced recovery after surgery protocols and postoperative complications after gastric surgery for cancer (POWER 4): a nationwide, prospective multicentre study.

INTRODUCTION: The effectiveness of the Enhanced Recovery After Surgery (ERAS) protocols in gastric cancer surgery remains controversial. METHODS: Multicentre prospective cohort study of adult patients undergoing surgery for gastric cancer. Adherence with 22 individual components of ERAS pathways were assessed in all patients, regardless of whether they were treated in a self-designed ERAS centre. Each centre had a three-month recruitment period between October 2019 and September 2020. The primary outcome was moderate-to-severe postoperative complications within 30 days after surgery. Secondary outcomes were overall postoperative complications, adherence to the ERAS pathway, 30 day-mortality and hospital length of stay (LOS). RESULTS: A total of 743 patients in 72 Spanish hospitals were included, 211 of them (28.4 %) from self-declared ERAS centres. A total of 245 patients (33 %) experienced postoperative complications, graded as moderate-to-severe complications in 172 patients (23.1 %). There were no differences in the incidence of moderate-to-severe complications (22.3% vs. 23.5%; OR, 0.92 (95% CI, 0.59 to 1.41); P = 0.068), or overall postoperative complications between the self-declared ERAS and non-ERAS groups (33.6% vs. 32.7%; OR, 1.05 (95 % CI, 0.70 to 1.56); P = 0.825). The overall rate of adherence to the ERAS pathway was 52% [IQR 45 to 60]. There were no differences in postoperative outcomes between higher (Q1, > 60 %) and lower (Q4, ≤ 45 %) ERAS adherence quartiles. CONCLUSIONS: Neither the partial application of perioperative ERAS measures nor treatment in self-designated ERAS centres improved postoperative outcomes in patients undergoing gastric surgery for cancer. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT03865810.

Biomarker-guided intervention to prevent acute kidney injury after major surgery (BigpAK-2 trial): study protocol for an international, prospective, randomised controlled multicentre trial.

INTRODUCTION: Previous studies demonstrated that the implementation of the Kidney Disease Improving Global Outcomes (KDIGO) guideline-based bundle, consisting of different supportive measures in patients at high risk for acute kidney injury (AKI), might reduce rate and severity of AKI after surgery. However, the effects of the care bundle in broader population of patients undergoing surgery require confirmation. METHODS AND ANALYSIS: The BigpAK-2 trial is an international, randomised, controlled, multicentre trial. The trial aims to enrol 1302 patients undergoing major surgery who are subsequently admitted to the intensive care or high dependency unit and are at high-risk for postoperative AKI as identified by urinary biomarkers (tissue inhibitor of metalloproteinases 2*insulin like growth factor binding protein 7 (TIMP-2)*IGFBP7)). Eligible patients will be randomised to receive either standard of care (control) or a KDIGO-based AKI care bundle (intervention). The primary endpoint is the incidence of moderate or severe AKI (stage 2 or 3) within 72 hours after surgery, according to the KDIGO 2012 criteria. Secondary endpoints include adherence to the KDIGO care bundle, occurrence and severity of any stage of AKI, change in biomarker values during 12 hours after initial measurement of (TIMP-2)*(IGFBP7), number of free days of mechanical ventilation and vasopressors, need for renal replacement therapy (RRT), duration of RRT, renal recovery, 30-day and 60-day mortality, intensive care unit length-of-stay and hospital length-of-stay and major adverse kidney events. An add-on study will investigate blood and urine samples from recruited patients for immunological functions and kidney damage. ETHICS AND DISSEMINATION: The BigpAK-2 trial was approved by the Ethics Committee of the Medical Faculty of the University of Münster and subsequently by the corresponding Ethics Committee of the participating sites. A study amendment was approved subsequently. In the UK, the trial was adopted as an NIHR portfolio study. Results will be disseminated widely and published in peer-reviewed journals, presented at conferences and will guide patient care and further research. TRIAL REGISTRATION NUMBER: NCT04647396.

Comparative Bioavailability and Pharmacokinetics Between the Solid Form of Metformin vs a Novel Liquid Extemporaneous Formulation in Children.

Metformin pharmacokinetics in a liquid extemporaneous formulation from commercial tablets was determined in paediatric patients. A randomized, transversal clinical trial was conducted in 34 children and adolescents between 7 and 17 years of age. 17 children were randomized to take metformin in the liquid formulation and, after a 1-week wash period, a 500 mg metformin tablet was administered to them. Blood samples were obtained in Whatman 903® cards at 0, 1, 2, 4, 8, 12 and 24 hours. Extraction was made by direct precipitation with acetonitrile (ACN) and methanol, detection by UPLC and tandem mass spectrometry. The method was accurate, precise, selective and linear from 50 to 1000 ng/mL (r = .9982). Comparative pharmacokinetics, tablet vs formulation, were as follows: Cmax 1503.2 ng/mL vs 1521.4, Tmax 1.5 h vs 2.3, and half-life 8.2 vs 7.5 h. The liquid formulation of metformin showed similar pharmacokinetics to the tablet, and the ratios (90% CI) of geometric mean for metformin were 100.63% (89.13-113.6), 98.08% (88.04-109.2), and 97.52% (84.9-112.01), for Cmax, AUC0-t, and AUC 0-∞, respectively. Pharmacokinetics was determined using WinNonlin Pro 3.1 software. The liquid formulation of metformin showed similar pharmacokinetics to the tablet, allowing a more precise dose adjustment and ease of administration.

The L125F MATE1 variant enriched in populations of Amerindian origin is associated with increased plasma levels of metformin and lactate.

Genetic factors that affect variability in metformin response have been poorly studied in the Latin American population, despite its being the initial drug therapy for type 2 diabetes, one of the most prevalent diseases in that region. Metformin pharmacokinetics is carried out by members of the membrane transporters superfamily (SLCs), being the multidrug and toxin extrusion protein 1 (MATE1), one of the most studied. Some genetic variants in MATE1 have been associated with reduced in vitro metformin transport. They include rs77474263 p.[L125F], a variant present at a frequency of 13.8% in Latin Americans, but rare worldwide (less than 1%). Using exome sequence data and TaqMan genotyping, we revealed that the Mexican population has the highest frequency of this variant: 16% in Mestizos and 27% in Amerindians, suggesting a possible Amerindian origin. To elucidate the metformin pharmacogenetics, a children cohort was genotyped, allowing us to describe, for the first time, a MATE1 rs77474263 TT homozygous individual. An additive effect of the L125F variant was observed on blood metformin accumulation, revealing the highest metformin and lactate serum levels in the TT homozygote, and intermediate metformin values in the heterozygotes. Moreover, a molecular dynamics analysis suggested that the genetic variant effect on metformin efflux could be due to a decreased protein permeability. We conclude that pharmacogenetics could be useful in enhancing metformin pharmacovigilance in populations having a high frequency of the risk genotype, especially considering that these populations also have a higher susceptibility to the diseases for which metformin is the first-choice drug.

The immunogenetic diversity of the HLA system in Mexico correlates with underlying population genetic structure.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) allele groups and alleles by PCR-SSP based typing in a total of 15,318 mixed ancestry Mexicans from all the states of the country divided into 78 sample sets, providing information regarding allelic and haplotypic frequencies and their linkage disequilibrium, as well as admixture estimates and genetic substructure. We identified the presence of 4268 unique HLA extended haplotypes across Mexico and find that the ten most frequent (HF > 1%) HLA haplotypes with significant linkage disequilibrium (Δ'≥0.1) in Mexico (accounting for 20% of the haplotypic diversity of the country) are of primarily Native American ancestry (A*02~B*39~DRB1*04~DQB1*03:02, A*02~B*35~DRB1*08~DQB1*04, A*68~B*39~DRB1*04~DQB1*03:02, A*02~B*35~DRB1*04~DQB1*03:02, A*24~B*39~DRB1*14~DQB1*03:01, A*24~B*35~DRB1*04~DQB1*03:02, A*24~B*39~DRB1*04~DQB1*03:02, A*02~B*40:02~DRB1*04~DQB1*03:02, A*68~B*35~DRB1*04~DQB1*03:02, A*02~B*15:01~DRB1*04~DQB1*03:02). Admixture estimates obtained by a maximum likelihood method using HLA-A/-B/-DRB1 as genetic estimators revealed that the main genetic components in Mexico as a whole are Native American (ranging from 37.8% in the northern part of the country to 81.5% in the southeastern region) and European (ranging from 11.5% in the southeast to 62.6% in northern Mexico). African admixture ranged from 0.0 to 12.7% not following any specific pattern. We were able to detect three major immunogenetic clusters correlating with genetic diversity and differential admixture within Mexico: North, Central and Southeast, which is in accordance with previous reports using genome-wide data. Our findings provide insights into the population immunogenetic substructure of the whole country and add to the knowledge of mixed ancestry Latin American population genetics, important for disease association studies, detection of demographic signatures on population variation and improved allocation of public health resources.

Genetic diversity of HLA system in a population from Guerrero, Mexico.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 144 Mexicans from the state of Guerrero to obtain information regarding allelic and haplotypic frequencies. We find that the ten most frequent haplotypes in the state of Guerrero include eight Native American and two European haplotypes. Admixture estimates revealed that the main genetic components in the state of Guerrero are Native American (61.36 ±â€¯2.69% by ML; 54.17% of Native American haplotypes) and European (35.01 ±â€¯4.59% by ML; 32.29% of European haplotypes), and a relatively low African genetic component (3.63 ±â€¯2.38% by ML; 5.90% of African haplotypes).

Genetic diversity of HLA system in two populations from Chiapas, Mexico: Tuxtla Gutiérrez and rural Chiapas.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 173 Mexicans from the state of Chiapas living in the city of Tuxtla Gutiérrez (N = 52) and rural communities (N = 121), to obtain information regarding allelic and haplotypic frequencies. We found that the most frequent haplotypes in Chiapas include 12 Native American and one European haplotype. Admixture estimates revealed that the main genetic components in Chiapas are Native American (71.61 ±â€¯0.58% by ML; 53.16% of Native American haplotypes) and European (26.39 ±â€¯5.05% by ML; 25.86% of European haplotypes), and a less prominent African genetic component (2.00 ±â€¯5.20% by ML; 9.77% of African haplotypes).

Genetic diversity of HLA system in two populations from Hidalgo, Mexico: Pachuca and rural Hidalgo.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 122 Mexicans from the state of Hidalgo living in the city of Pachuca (N = 41) and rural communities (N = 81), to obtain information regarding allelic and haplotypic frequencies. We find that the most frequent haplotypes in Hidalgo include eight Native American and one European haplotypes. Admixture estimates revealed that the main genetic components in Hidalgo are Native American (58.93 ±â€¯2.16% by ML; 54.51% of Native American haplotypes) and European (32.49 ±â€¯2.88% by ML; 28.69% of European haplotypes), and a relatively high African genetic component (8.58 ±â€¯0.93% by ML; 6.97% of African haplotypes).

Genetic diversity of HLA system in two populations from Querétaro, Mexico: Querétaro city and rural Querétaro.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 88 Mexicans from the state of Querétaro living in the city of Querétaro (N = 45) and rural communities (N = 43), to obtain information regarding allelic and haplotypic frequencies. We find that the most frequent haplotypes in the state of Querétaro include seven Native American, two European and one Asian haplotype. Admixture estimates revealed that the main genetic components in the state of Querétaro are Native American (51.82 ±â€¯4.42% by ML; 42.61% of Native American haplotypes) and European (48.18 ±â€¯3.55% by ML; 46.02% of European haplotypes), with a virtually absent African genetic component (0.00 ±â€¯4.25% by ML; 4.55% of African haplotypes).

Genetic diversity of HLA system in six populations from Mexico City Metropolitan Area, Mexico: Mexico City North, Mexico City South, Mexico City East, Mexico City West, Mexico City Center and rural Mexico City.

We studied HLA class I (HLA-A, -B) and class II (HLA-DRB1, -DQB1) alleles by PCR-SSP based typing in 1217 Mexicans from the Mexico City Metropolitan Area living in the northern (N = 751), southern (N = 52), eastern (N = 79), western (N = 33), and central (N = 152) Mexico City, and rural communities (N = 150), to obtain information regarding allelic and haplotypic frequencies. We found that the most frequent haplotypes include 11 Native American haplotypes. Admixture estimates revealed that the main genetic components are Native American (63.85 ±â€¯1.55% by ML; 57.19% of Native American haplotypes) and European (28.53 ±â€¯3.13% by ML; 28.40% of European haplotypes), and a less apparent African genetic component (7.61 ±â€¯1.96% by ML; 7.17% of African haplotypes).

Critically ill patients with community-onset intraabdominal infections: Influence of healthcare exposure on resistance rates and mortality.

The concept of healthcare-associated infections (as opposed to hospital-acquired infections) in intraabdominal infections (IAIs) is scarcely supported by data in the literature. The aim of the present study was to analyse community-onset IAIs (non-postoperative/non-nosocomial) in patients admitted to intensive care units (ICUs), to investigate differences in resistance patterns linked to healthcare exposure and mortality-associated factors. A one-year prospective observational study (17 Spanish ICUs) was performed distributing cases as healthcare-associated infections (HCAI), community-acquired infections (CAI) and immunocompromised patients (ICP). Bacteria producing extended-spectrum ß-lactamases (ESBL) and/or carbapenemase (CPE), high-level aminoglycoside- and/or methicillin- and/or vancomycin- resistance were considered antimicrobial resistant (AMR). Mortality-associated factors were identified by regression multivariate analysis. Of 345 patients included (18.8% HCAI, 6.1% ICP, 75.1% CAI), 51.6% presented generalized peritonitis; 32.5% were >75 years (55.4% among HCAI). Overall, 11.0% cases presented AMR (7.0% ESBL- and/or CPE), being significantly higher in HCAI (35.4%) vs. CAI (5.8%) (p<0.001) vs. ICP (0%) (p = 0.003). Overall 30-day mortality was 14.5%: 23.1% for HCAI and 11.6% for CAI (p = 0.016). Mortality (R2 = 0.262, p = 0.021) was positively associated with age >75 years (OR = 6.67, 95%CI = 2.56-17.36,p<0.001), Candida isolation (OR = 3.05, 95%CI = 1.18-7.87,p = 0.022), and SAPS II (per-point, OR = 1.08, 95%CI = 1.05-1.11, p<0.001) and negatively with biliary infections (OR = 0.06, 95%CI = 0.01-0.48,p = 0.008). In this study, the antimicrobial susceptibility pattern of bacteria isolated from patients with healthcare contact was shifted to resistance, suggesting the need for consideration of the healthcare category (not including hospital-acquired infections) for severe IAIs. 30-day mortality was positively related with age >75 years, severity and Candida isolation but not with AMR.

Determination of blood dexmedetomidine in dried blood spots by LC-MS/MS to screen therapeutic levels in paediatric patients.

Dexmedetomidine is an imidazole derivative, with high affinity for α2 adrenergic receptors, used for sedation, analgesia and adjuvant anaesthesia. In this study, an analytical method for the quantification of dexmedetomidine in dried blood spots was developed, validated and applied. The drug was extracted from dried blood spot by liquid extraction; the separation was carried out by ultra high-resolution liquid chromatography in reverse phase coupled to tandem mass spectrometry method. An X Select cyano 5 µm HSS column (2.1 X 150 mm, Waters) and a mobile phase composed of 0.1% formic acid: acetonitrile [50:50 v/v], were used. The test was linear over the concentration range of 50 to 2000 pg/mL. The coefficients of variation for the intra and interday trials were less than 15%. The drug was stable under the conditions tested. The method was successfully applied for the quantification of 6 patients, aged 0 to 2 years, with classification ASA I, who underwent ambulatory surgeries, receiving a dose of 1 µg/Kg dexmedetomidine IV. The drug concentrations in the different sampling times were in the range of 76 to 868 pg/mL.

Extemporaneous Formulations of Metformin for Pediatric Endocrinology: Physicochemical Integrity, Cytotoxicity of Sweeteners, and Quantitation of Plasma Levels.

PURPOSE: In response to the lack of pediatric formulations of metformin to control type 2 diabetes mellitus, hyperinsulinemic obesity, and dyslipidemias, we developed liquid formulations of metformin by dissolving 3 generic brands of 500-mg metformin(*,)(†,)(‡) tablets in water sweetened with sucralose. The physicochemical stabilities of these drugs were assessed and compared with those of formulations made with the innovative brand of metformin.(∥) A method to measure metformin plasma levels was proposed and then tested in 2 healthy subjects. This method may be useful to survey treatment compliance in the future. The biological safety profiles of the metformin solutions were assessed preliminarily in a system of hormone-dependent cancer cells (human breast cancer MCF-7 cells). METHODS: Metformin solutions stored at 25°C exposed to light and at 25°C, 4°C, and 40°C protected from light, underwent physicochemical analysis by ultra-performance liquid chromatography with ultraviolet detection, the mobile phase consisting of 0.2 M potassium monobasic phosphate (pH 6.5), 4.6 mM sodium dodecyl sulphate (SDS), and acetonitrile (63:7:30) at a flow rate of 0.8 mL/min in a Symmetry C8 150 × 4.6 mm column (Milford, Massachusetts) at 40°C (236 nm). MCF-7 cells were grown in 96-well ELISA plates (2 × 10(5) cells/well) and were exposed to 10, 20, and 40 mg/mL sucralose(§), Stevia rebaudiana (Svetia; Metco, S.A. de C.V., México, D.F., Mexico), and metformin (50 mg/mL) for 48 hours. Cytotoxicity was determined using the WST-1 colorimetric assay (Roche, USA) in an Epoch ELISA reader (BioTek, Winooski, Vermont) at 440 nm. FINDINGS: All brands of metformin were stable at all storage conditions for up to 30 days and retained >90% of the initial amount. Sucralose and Stevia rebaudiana caused zero cytotoxicity (ANOVA, P ≤ 0.05). The ultra-performance liquid chromatography with ultraviolet detection method was adapted to determine metformin level in very small blood samples (40 µL), which was linear within the range of 20 to 600 ng/mL metformin (retention time 2 minutes). Metformin was physically and chemically stable within the processed blood for up to 30 days at 4°C. IMPLICATIONS: Extemporaneous formulations of metformin may be developed at low cost from either the innovator or generic brands, and both sucralose and Stevia rebaudiana sweeteners may be well tolerated; however, the minimum amount of sweetener is recommended to avoid any endocrine disturbance. The analytical method is accurate and precise to clinically measure metformin levels in patients taking the extemporaneous formulation orally. Study registry identification number: 100/2013.

The administration of food supplemented with cocoa powder during nutritional recovery reduces damage caused by oxidative stress in rat brain.

Malnutrition contributes to the development of oxidative damage in the central nervous system. The selective administration of nutrients tends to show positive results in individuals who have suffered from malnutrition. To determine the effect of the administration of cocoa powder on the peroxidation of lipids and glutathione level during the nutritional recovery in brain, rats of 21 days old were subjected to a protocol that resembles malnutrition (MN) by feeding them with 60% of the daily food consumption of the control group (WN) and later to nutritional recovery with regular rodent feed (RFR) or added with cocoa (10 g of cocoa powder/kg of regular rodent feed) (CCR). Animals fed with regular rodent food showed significant reduction in brain glutathione: RFR (84.18 ± 6.38 ng/mg protein) vs. CCR (210.61 ± 50.10 ng/mg protein) and WN (186.55 ± 33.18 ng/mg protein), but with similar level to that of MN (92.12 ± 15.60 ng/mg protein). On the contrary, lipid peroxidation in RFR-fed animals increased RFR (1.32 ± 0.2 µM malondialdehyde/g of tissue), CCR (0.86 ± 0.07 µM malondialdehyde/g of tissue), WN (0.89 ± 0.09 µM malondialdehyde/g of tissue), but their thiobarbituric acid reactive substances concentration is similar to that of MN group (1.50 ± 0.2 µM malondialdehyde/g of tissue). Consumption of cocoa powder as a source of antioxidants favors the restoration of the concentration of glutathione and reduces the damage caused by oxidative stress during nutritional recovery in rat brain.

A reliable method of liquid chromatography for the quantification of acetaminophen and identification of its toxic metabolite N-acetyl-p-benzoquinoneimine for application in pediatric studies.

The aim of the present study was to develop a simple, selective and reliable method to quantify acetaminophen and its toxic metabolite N-acetyl-p-benzoquinoneimine (NAPQI) for pediatric studies using 100 µL plasma samples, by reverse-phase HPLC and UV detection. The assay was performed using a C18 column and an isocratic elution with water-methanol-formic acid (70:30:0.15; v/v/v) as mobile phase. Linearity of the method was assayed in the range of 1-30 µg/mL for acetaminophen and 10-200 µg/mL for NAPQI, with a correlation coefficient r = 0.999 for both compounds, and inter- and intra-day coefficients of variation of less than 13%. Several commonly co-administered drugs were analyzed for selectivity and no interference with the determinations was observed. The detection and quantification limits for acetaminophen and NAPQI were 0.1 and 1 µg/mL, and 0.1 and 10 µg/mL respectively. The present method can be used to monitor acetaminophen levels using 100 µL plasma samples, which may be helpful when very small samples need to be analyzed, as in pharmacokinetics determination or drug monitoring in plasma in children. This assay is also able to detect the NAPQI for drug monitoring in patients diagnosed with acetaminophen intoxication.

Oxidative stress induced by morphine in brain of rats fed with a protein deficient diet.

The objective of the study is to determine the damage by oxidative stress induced by morphine in brain of rats fed with a protein-deficient diet. Twenty-eight malnourished male Wistar rats, 30 days old, were used in the study. The animals were divided into four groups of 7 rats per group. Group I received NaCl and the groups II; III and IV intraperitoneally received 3, 6 and 12 mg/kg of morphine sulphate, respectively, in a single dose. Animals were sacrificed and the levels of glutathione (GSH), dopamine, tryptophan and 5-hydroxyindole-3-acetic acid (5-HIAA) as well as, Na(+)/K(+) ATPase and total ATPase activity in the brain were measured. Tryptophan levels and Na(+)/K( +) ATPase activity showed non-significant changes in the experimental group. Levels of 5-HIAA decreased significantly (p = .03) in animals that received 12 mg/kg of morphine and in animals that received 3 mg/kg, levels of GSH and dopamine were found to have a significant decrease (p < .05), but a significant increase in the group that received 12 mg/kg of morphine (p < .05). Total ATPase activity increased significantly in the groups that received 3 mg/kg (p = .015) and 6 mg/kg (p = .0001) of morphine. The results show that malnutrition induces changes in cellular regulation and biochemical responses to oxidative stress caused by morphine sulphate.

Levels of glutathione and some biogenic amines in the human brain putamen after traumatic death.

Mexico City is among the world's largest metropolitan city centers and one of the most difficult and challenging cities in which to drive a motor vehicle. During peak transit hours and maximum congestion, numerous accidents occur, many of them fatal. The aim of the study presented here was to analyze the levels of select indicators against oxidative stress and levels of biogenic amines as a consequence of accident or altercation and fear deaths. Eighteen cases were studied (sixteen males, two females). Subjects ranged from twelve to eighty-one years of age. Nine of the deaths studied were the result of motor vehicle or subway accidents. Eight of the eighteen deaths were the result of a violent altercation, while one of the deaths resulted from a drug overdose and cardiac arrest. Biopsies of cadaver putamen were homogenized and analyzed for Tryptophan (Trp), 5-hydroxyindole acetic acid (5-HIAA), Dopamine (DA), and Glutathione (GSH) levels by fluorometric methods. Trp, 5-HIAA, DA, and GSH levels showed an increase in the subjects who's death was caused by violent altercation combined with fear, while DA levels showed significant differences in all accident groups. This data suggest that biogenic amines in cadaver putamen tissue, such as DA, can be telling biochemical markers, indicative of altercation and fear deaths.