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BACKGROUND: Increased hemoglobin concentrations may increase the risk of varicose veins. However, the underlying relationship between them was not yet understood. METHODS: Mendelian randomization (MR) analysis was performed to investigate causal effect between mean corpuscular hemoglobin concentration (MCHC, exposure factor) and varicose veins (outcome). Afterward, sensitivity analysis was used to ensure the reliability of MR analysis results. Then Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of SNPs were performed. A search tool for recurring instances of neighbouring genes (STRING) database was used to construct a protein-protein interaction (PPI) network. RESULTS: Therefore, the inverse-variance weighted (IVW) results showed there existed a causal relationship between MCHC and varicose veins (p = 0.0026), with MCHC serving as a significant risk factor. (odd ratio [OR] = 1.2321). In addition, the validity of the results of the forward MR analysis was verified by sensitivity analysis. Further, a PPI network of 92 single-nucleotide polymorphisms (SNPs) which used for forward MR analysis related genes was constructed. And they were found to be closely associated with the peroxisome proliferator-activated receptor (PPAR) signalling pathway and cellular response to external stimulus by enrichment analysis. In addition, we clarified that the effect of varicose veins on MCHC was minimal by reverse MR analysis, suggesting that the results of forward MR analysis were not disturbed by reverse results. CONCLUSION: This study found a causal relationship between varicose veins and MCHC, which provided strong evidence for the effect of hemoglobin on varicose veins, and a new thought for the diagnosis and prevention of varicose veins in the future.

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Objective: To explore the risk of low-level blood group antibody-mediated hemolysis in ABO-incompatible newborns with negative three hemolysis tests, aiming to assist in the identification and management of neonatal jaundice. Methods: A retrospective case-control study was performed in 892 children with jaundice. The patients were divided into three groups: group I, ABO compatible, negative three hemolysis tests; group II, ABO incompatible, negative three hemolysis tests; and group III, ABO incompatible, positive three hemolysis tests. We analyzed the differences in clinical data, blood routine and biochemical laboratory results. Results: (1) Patients in group II had higher levels of mean corpuscular volume (MCV), standard deviation of red blood cell volume distribution width (RDW-SD), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), and bile acid (BA) than those in group I (P < 0.05). However, there were no statistically significant differences in the MCV, ALT, ALP and BA levels between groups II and III (P > 0.05). (2) Mean corpuscular hemoglobin concentration (MCHC) >359.5 g/L, cell volume distribution width (RDW-CV) >15.95%, and reticulocyte count (RET) >4.235% were identified as independent predictors of positive hemolysis test results (P < 0.001). The combination of MCHC, RDW-CV, and RET% yielded an AUC of 0.841. Conclusion: Low-level blood group antibody-mediated hemolysis may occur in ABO-incompatible neonates even when three hemolysis tests are negative. Changes in liver function parameters must be monitored. The combination of MCHC, RDW-CV, and RET% can be used to improve the detection rate of HDN.

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To explore preoperative and operative risk factors for red blood cell (RBC) transfusion requirements during liver transplantation (LT) and up to 24 h afterwards. We evaluated the associations between risk factors and units of RBC transfused in 176 LT patients using a log-binomial regression model. Relative risk was adjusted for age, sex, and the model for end-stage liver disease score (MELD) (adjustment 1) and baseline hemoglobin concentration (adjustment 2). Forty-six patients (26.14%) did not receive transfusion. Grafts from cardiac-death donors were used in 32.61% and 31.54% of non-transfused and transfused patients, respectively. The transfused group required more reoperation for bleeding (P = 0.035), longer mechanical ventilation after LT (P < 0.001), and longer ICU length of stay (P < 0.001). MELD and hemoglobin concentrations determined RBC requirements. For each unit of increase in the MELD score, 2% more RBC units were transfused, and non-transfusion was 0.83-fold less likely. For each 10-g/L higher hemoglobin concentration at baseline, 16% less RBC transfused, and non-transfusion was 1.95-fold more likely. Ascites was associated with 26% more RBC transfusions. With an increase of 2 mm from the baseline in the A10FIBTEM measurement of maximum clot firmness, non-transfusion was 1.14-fold more likely. A 10-min longer cold ischemia time was associated with 1% more RBC units transfused, and the presence of post-reperfusion syndrome with 45% more RBC units. We conclude that preoperative correction of anemia should be included in LT. An intervention to prevent severe hypotension and fibrinolysis during graft reperfusion should be explored.Trial register: European Clinical Trials Database (EudraCT 2018-002,510-13) and ClinicalTrials.gov (NCT01539057).

Asunto(s)

Trasplante de Hígado , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Transfusión Sanguínea , Enfermedad Hepática en Estado Terminal/cirugía , Transfusión de Eritrocitos , Hemoglobinas/metabolismo , Hemoglobinas/análisis , Tiempo de Internación , Trasplante de Hígado/efectos adversos , Trasplante de Hígado/métodos , Factores de Riesgo

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BACKGROUND: Lower extremity peripheral arterial disease is a potentially lethal cardiovascular complication in patients undergoing hemodialysis. Anemia is a risk factor for cardiovascular disease among the hemodialysis population. However, whether blood hemoglobin concentration is associated with the risk of peripheral arterial disease progression in this population remains undetermined. METHODS AND RESULTS: This is an extension of a 4-year multicenter, prospective, observational cohort study to 10 years. A total of 3504 Japanese patients undergoing maintenance hemodialysis were recruited between 2006 and 2007. The primary exposure was blood hemoglobin concentration at baseline. The main outcome was the first-ever incidence of major adverse limb events (MALE), composed of endovascular treatment, bypass surgery, and amputation. Multivariable-adjusted Cox proportional hazards model, Fine-Gray subdistribution hazards model, restricted cubic spline analysis, and restricted mean survival time analysis were used to determine the association of blood hemoglobin concentration with the incidence of MALE. During a median follow-up of 8.0 years, 257 patients experienced MALE. A Cox proportional hazards model showed that the risk of MALE in patients with blood hemoglobin concentrations <10.0 g/dL was significantly higher than in patients with concentrations of 11.0 to 11.9 g/dL, even after adjusting for confounding factors. In contrast, elevated hemoglobin concentration (≥12.0 g/dL) was not significantly associated with increased risk of MALE. Similar associations were observed when the Fine-Gray subdistribution regression model was used by setting all-cause mortality as the competing risk. CONCLUSIONS: A low blood hemoglobin concentration is an independent risk factor for peripheral arterial disease progression in patients undergoing maintenance hemodialysis.

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Hemoglobinas , Extremidad Inferior , Enfermedad Arterial Periférica , Diálisis Renal , Humanos , Masculino , Enfermedad Arterial Periférica/epidemiología , Enfermedad Arterial Periférica/sangre , Enfermedad Arterial Periférica/diagnóstico , Enfermedad Arterial Periférica/mortalidad , Diálisis Renal/efectos adversos , Femenino , Hemoglobinas/metabolismo , Hemoglobinas/análisis , Incidencia , Anciano , Persona de Mediana Edad , Estudios Prospectivos , Extremidad Inferior/irrigación sanguínea , Japón/epidemiología , Factores de Riesgo , Amputación Quirúrgica/estadística & datos numéricos , Factores de Tiempo , Modelos de Riesgos Proporcionales , Anemia/epidemiología , Anemia/sangre , Fallo Renal Crónico/terapia , Fallo Renal Crónico/sangre , Fallo Renal Crónico/mortalidad , Fallo Renal Crónico/complicaciones , Biomarcadores/sangre , Factores Sexuales , Progresión de la Enfermedad , Medición de Riesgo/métodos

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BACKGROUND AND AIMS: High temperatures may reduce fecal immunochemical test (FIT) positivity and colorectal cancer (CRC) detection sensitivity. We investigated the effect of temperature on hemoglobin concentration [Hb], in the FOB Gold®. Additionally, we examined FIT pick-up, storage, return times and specimen collection. MATERIALS AND METHODS: In vitro experiments with buffer containing FIT devices, inoculated with Hb-spiked stool. For 7 days, 144 samples were stored in groups of 36 at 4 °C, 22 °C, 30 °C, and 50 °C. Additionally, 54 samples were stored in groups of 18 at 34 °C, 42 °C and 50 °C for 20 h. Paired t-tests and repeated measure ANOVA assessed [Hb] change. Sixty-five screening participants completed a FIT-handling questionnaire. RESULTS: After 7 days, mean [Hb] was stable at 30 °C (0.8 µg Hb/g;95 %CI: -1.5 to 3.1;p = 0.50). For 50 °C, mean [Hb] decreased within 2 days (-21.3 µg Hb/g;95 %CI: -30.2 to -12.5;p < 0.001) and after 20 h (-63.0 µg Hb/g;95 %CI: -88.7 to -37.3;p < 0.001), respectively. All other temperature categories showed significant mean [Hb] increase. Same-day FIT return was reported by 80 %. Eighty-seven percent experienced specimen collection as easy and 33 % kept the FIT refrigerated after collection. CONCLUSIONS: The FOB Gold® is suitable for CRC screening in tropical climates. Although most respondents indicated same-day sample return, we recommend avoiding FIT storage above 30 °C for longer than7 days.

Asunto(s)

Neoplasias Colorrectales , Detección Precoz del Cáncer , Heces , Hemoglobinas , Humanos , Neoplasias Colorrectales/diagnóstico , Hemoglobinas/análisis , Detección Precoz del Cáncer/métodos , Heces/química , Región del Caribe , Sangre Oculta , Masculino , Femenino , Persona de Mediana Edad , Calor , Inmunoquímica , Anciano

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Background: The relationship between hemoglobin concentration and stroke has garnered significant interest in the research community. However, findings from published observational epidemiological studies on this relationship have been inconclusive. By using publicly available genome-wide association study (GWAS) aggregated statistics, a two-sample Mendelian randomization analysis is conducted to explore the causal relationship between hemoglobin concentration and stroke. Methods: Summary statistics data from UK Biobank for hemoglobin concentration and from the FinnGen R9 and MEGASTROKE consortium for stroke are used. A series of quality control steps are taken to select eligible instrumental SNPs closely related to exposure. In order to make the conclusion more robust and reliable, several robust analysis methods are employed including inverse variance weighted, weighted median, MR-Egger regression, which are based on different assumptions of two-sample MR Analysis. Meanwhile, sensitivity analyses such as pleiotropy test and MR-Egg regression, are performed to mitigate horizontal pleiotropy and heterogeneity. Results: The two-sample Mendelian randomized study indicates a negative association between hemoglobin concentration and stroke, suggesting that hemoglobin concentration acts as a protective factor against stroke. From the FinnGen database, there is a negative association between hemoglobin concentration and stroke, with an odds ratio (OR) of 0.82 and a 95% confidence interval (CI) of 0.73-0.92, p = 0.0006. Similarly, the MEGASTROKE database findings reinforce this observation. The negative association between hemoglobin concentration and stroke (OR: 0.91, 95%CI: 0.83-1.00, p = 0.040), ischemic stroke (OR: 0.87, 95%CI: 0.79-0.96, p = 0.004), and cardiogenic stroke (OR: 0.82, 95% CI: 0.69-0.99, p = 0.039) further suggests that higher hemoglobin levels might confer a protective effect against these conditions. Conclusion: Hemoglobin concentration serves as a protective factor against stroke, and managing abnormal hemoglobin levels can effectively reduce the incidence of stroke.

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Plasma volume (PV) undergoes constant and dynamic changes, leading to a large intra-day variability in healthy individuals. Hydration is known to induce PV changes; however, the response to the intake of osmotically different fluids is still not fully understood. In a randomized controlled crossover trial, 18 healthy individuals (10 females) orally received an individual amount of an isotonic sodium-chloride (ISO), Ringer (RIN), or glucose (GLU) solution. Hemoglobin mass (Hbmass) was determined with the optimized carbon monoxide re-breathing method. Fluid-induced changes in PV were subsequently calculated based on capillary hemoglobin concentration ([Hb]) and hematocrit (Hct) before and then every 10 minutes until 120 min (t0-120) after the fluid intake and compared to a control trial arm (CON), where no fluid was administered. Within GLU and CON trial arms, no statistically significant differences from baseline until t120 were found (p > 0.05). In the ISO trial arm, PV was significantly increased at t70 (+138 mL, p = 0.01), t80 (+191 mL, p < 0.01), and t110 (+182 mL, p = 0.01) when compared to t0. Moreover, PV in the ISO trial arm was significantly higher at t70 (p = 0.02), t110 (p = 0.04), and t120 (p = 0.01) when compared to the same time points in the CON trial arm. Within the RIN trial arm, PV was significantly higher between t70 and t90 (+183 mL, p = 0.01) and between t110 (+194 mL, p = 0.03) and t120 (+186 mL, p < 0.01) when compared to t0. These results demonstrated that fluids with a higher content of osmotically active particles lead to acute hemodilution, which is associated with a decrease in [Hb] and Hct. These findings underpin the importance of the hydration state on PV and especially on PV constituent levels in healthy individuals.

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Background: The neurotoxic effects of lead in children can have long-lasting and profound impacts on the developing nervous system. This study aimed to identify a reliable and easily accessible biomarker to monitor neurological impairment in lead-poisoned children. Methods: We analyzed hematological data from 356 lead-poisoned children, comparing them with age and gender-matched healthy controls. Multivariate logistic regression and receiver operating characteristic (ROC) analysis were employed to identify and evaluate potential biomarkers for neurological damage. Results: Significant changes in erythrocyte parameters were observed in lead-poisoned children. Upon further analysis, increased mean corpuscular hemoglobin concentration (MCHC) and red cell distribution width-standard deviation (RDW-SD) interaction values were found to be significantly associated with neurological impairment. The MCHC*RDW-SD interaction model demonstrated an AUC of 0.76, indicating its effectiveness in reflecting neurological damage. Additionally, the MCHC*RDW-SD Interaction value showed weak or no correlation with other erythrocyte parameters, suggesting its independence as an indicator. Conclusion: Our findings propose the increased MCHC*RDW-SD interaction value as a robust and independent biomarker for detecting neurological impairment in lead-poisoned children. This underscores the potential of utilizing specific erythrocyte parameters for screening the neurotoxic effects of lead exposure in pediatric populations.

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Intoxicación por Plomo , Síndromes de Neurotoxicidad , Niño , Humanos , Índices de Eritrocitos , Intoxicación por Plomo/diagnóstico , Curva ROC , Biomarcadores

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Non-invasive detection of hemoglobin (Hb) concentration is of great clinical value for health screening and intraoperative blood transfusion. However, the accuracy and stability of non-invasive detection still need to be improved to meet clinical requirement. This paper proposes a non-invasive Hb detection method using ensemble extreme learning machine (EELM) regression based on eight-wavelength PhotoPlethysmoGraphic (PPG) signals. Firstly, a mathematical model for non-invasive Hb detection based on the Beer-Lambert law is established. Secondly, the captured eight-channel PPG signals are denoised and fifty-six feature values are extracted according to the derived mathematical model. Thirdly, a recursive feature elimination (RFE) algorithm is used to select the features that contribute most to the Hb prediction. Finally, a regression model is built by integrating several independent ELM models to improve prediction stability and accuracy. Experiments conducted on 249 clinical data points (199 cases as the training dataset and 50 cases as the test dataset) evaluate the proposed method, achieving a root mean square error (RMSE) of 1.72 g/dL and a Pearson correlation coefficient (PCC) of 0.76 (p < 0.01) between predicted and reference values. The results demonstrate that the proposed non-invasive Hb detection method exhibits a strong correlation with traditional invasive methods, suggesting its potential for non-invasive detection of Hb concentration.

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Algoritmos , Hemoglobinas , Correlación de Datos

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BACKGROUND: Deviations of hemoglobin from normal levels may be a factor in cardiovascular disease (CVD) risk; however, conclusive evidence is lacking. In addition, preclinical conditions may influence hemoglobin concentrations, but studies focusing on reverse causation are limited. Thus, we examined the relationship between hemoglobin concentrations and CVD mortality risk, considering reverse causation. METHODS AND RESULTS: In a prospective cohort representative of the general Japanese population (1990-2015), we studied 7,217 individuals (mean age 52.3 years; 4,219 women) without clinical CVD at baseline. Participants were categorized into sex-specific hemoglobin quintiles (Q1-Q5) and data were analyzed using the Cox proportional hazards model adjusted for possible confounders. During a 25-year follow-up, 272 men and 334 women died from CVD. Adjusted hazard ratios for CVD mortality across sex-specific quintiles, using Q3 as the reference, were significantly higher for Q1 (1.40; 95% confidence interval [CI] 1.08-1.82) and Q5 (1.49; 95% CI 1.14-1.96), and remained significant after excluding deaths within the first 5 years of follow-up to consider reverse causation (1.35 [95% CI 1.02-1.79] and 1.45 [95% CI 1.09-1.94], respectively). A similar U-shaped association was seen between transferrin saturation levels and CVD mortality, but after excluding deaths within the first 5 years the association was significant only for Q1. CONCLUSIONS: Low and high hemoglobin concentrations were associated with an increased risk of CVD mortality.

Asunto(s)

Enfermedades Cardiovasculares , Hemoglobinas , Humanos , Masculino , Femenino , Persona de Mediana Edad , Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/sangre , Hemoglobinas/análisis , Hemoglobinas/metabolismo , Japón/epidemiología , Estudios de Seguimiento , Estudios Prospectivos , Adulto , Anciano , Factores de Riesgo , Pueblos del Este de Asia

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Previous studies examining the association between hemoglobin concentration and hypertension have yielded inconsistent results. There is still a lack of evidence regarding the association between hemoglobin concentration and hypertension risk in native Tibetans at high altitude. We performed this cross-sectional study in Luhuo County of Ganzi Tibetan Autonomous Prefecture (average altitude of 3500 m). In this study, we enrolled 1547 native Tibetans. The association between hemoglobin concentration and hypertension risk was examined by multivariate binary logistic regression and smooth curve fitting. Native Tibetans with hypertension had significantly higher hemoglobin concentrations than those without hypertension (165.9 ± 21.5 g/L vs. 157.7 ± 19.2 g/L, P < 0.001). An increase in hemoglobin concentration of 1 g/L was associated with hypertension (odds ratio [OR] 1.02, 95% confidence interval [CI] 1.01-1.02) after confounder adjustment. The highest hemoglobin concentration group (exceeding 173 g/L) was associated with an increased hypertension risk compared with the bottom quartile of hemoglobin concentration (OR 2.39, 95% CI 1.48-3.85). Hemoglobin concentration (per 1 g/L change) exceeding 176 g/L was significantly associated with an increased hypertension risk (OR 1.04, 95% CI 1.03-1.06). Additionally, high-altitude polycythemia significantly increased the hypertension risk compared with a normal hemoglobin concentration (OR 2.92, 95% CI 1.25-6.86). A similar result was observed for mild polycythemia (OR 1.74, 95% CI 1.29-2.34). In conclusion, hemoglobin concentration was associated with hypertension risk in native Tibetans. When the hemoglobin concentration exceeded a certain value (approximately 176 g/L), the risk of hypertension was significantly increased.

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Pueblos del Este de Asia , Hipertensión , Policitemia , Humanos , Altitud , Estudios Transversales , Hipertensión/epidemiología , Hemoglobinas

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Purpose To investigate the value of red blood cell parameters in Myelodysplastic syndrome (MDS) diagnosis and their relations to MDS subtypes and risk groups. Methods The red blood cell parameter [mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC) and red cell distribution width (RDW)] levels [203 MDS, 99 aplastic anemia (AA), 145 megaloblastic anemia (MA)] were collected from a single-center retrospective cohort. The cut-off values, area under the receiver operating characteristic curve (ROC) curve (AUC), sensitivity and specificity of the four parameters were calculated from the ROC. Furthermore, Kruskal–Wallis test and Dunn’s Test were performed to determine erythrocyte parameters in different subtypes and prognostic risks MDS. Results There are significant statistic differences in RDW (P < 0.001), MCH (P = 0.036) and MCHC (P < 0.001) (MDS vs AA); RDW (P = 0.009), MCV (P < 0.001), MCH (P < 0.001) and MCHC (P = 0.001) (MDS vs MA); MCV (P = 0.011) and MCH (P = 0.008) (higher-risk MDS vs lower-risk MDS). Between MDS and MA, the area under the receiver operating characteristic curve (ROC) curve (AUC) values of MCV, MCH, MCHC, RDW were 0.846, 0.855, 0.617, and 0.593. Between MDS and AA, the AUC values of MCH, MCHC, RDW were 0.609, 0.671, and 0.662, respectively. Conclusions The red blood cell parameters contribute to the differential diagnosis of MDS, AA and MA and are related to MDS subtypes and risk groups (AU)

Asunto(s)

Humanos , Síndromes Mielodisplásicos/diagnóstico , Índices de Eritrocitos , Estudios Retrospectivos , Diagnóstico Diferencial , Pronóstico , Curva ROC

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Mammary neoplasms are common in felines species and represent a significant disease for its unfavorable prognosis. Changes in the blood count and serum biochemical profile of these patients have potential as non-invasive prognostic markers prior to mastectomy, however, they are poorly described in literature. In this study univariate and multivariate analyses were performed using these factors to determine the effect of each parameter on the one-year survival time after the surgical procedure in these animals. The median overall survival (OS) and the disease-free survival (DFS) were 365 and 242 days, respectively. In univariate analysis, values within the reference range of monocyte, platelet and creatinine counts were identified as significant prognostic factors for OS and only creatinine was significant for DFS (P < 0.05). In the multivariate analysis, platelets and mean corpuscular hemoglobin concentration (MCHC) remained independent prognostic factors for OS. The results presented suggest that monocytes, platelets and creatinine may be important non-invasive pre-surgical prognostic markers, and that platelet count and MCHC are independent prognostic markers for feline mammary carcinomas (FMC). The correlation between such alterations is of important relevance for veterinary oncology, and prospective studies are needed to validate their clinical use and that platelet count and MCHC are independent prognostic markers for FMC. The results found in this study can also be studied in human medicine, regarding blood markers in human breast cancer (HBC).

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Neoplasias de la Mama , Carcinoma , Enfermedades de los Gatos , Humanos , Animales , Gatos , Femenino , Pronóstico , Índices de Eritrocitos/veterinaria , Neoplasias de la Mama/veterinaria , Recuento de Plaquetas/veterinaria , Creatinina , Mastectomía/veterinaria , Estudios Retrospectivos , Carcinoma/veterinaria , Enfermedades de los Gatos/diagnóstico

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Aim: We investigated the clinical usefulness of mean corpuscular hemoglobin concentration (MCHC) in patients with pneumoconiosis. Methods: We retrospectively investigated the medical records from 52 patients with pneumoconiosis, and erythrocyte parameters were analyzed in pneumoconiosis patients with different stages. Results: Here, we found that the values of MCHC were significantly lower in III stage pneumoconiosis than those with I/II stage (p = 0.024), and there was no significantly difference in MCHC between smoking pneumoconiosis patients and non-smoking pneumoconiosis patients. A negatively correlation between MCHC and disease stage was observed in patients with pneumoconiosis (r = -0.298, p = 0.032). In multiple linear regression analysis, the MCHC was found to be independently associated with advanced pneumoconiosis in patients with pneumoconiosis (p=0.011). The results of logistic regression analysis indicated that decreased MCHC was an independent risk factor of advanced pneumoconiosis in patients with pneumoconiosis (OR: 0.936, CI95%: 0.877-0.999, p = 0.046). Receiver operating characteristic curve analysis showed that the optimal cutoff value of MCHC was 330 g/L to identify advanced pneumoconiosis with the area under the curve of 0.694 (CI95%:0.550-0.839, p = 0.018). Conclusion: The decreased MCHC is associated with advanced pneumoconiosis, and MCHC may be used as a monitoring marker for follow-up of pneumoconiosis patients.

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We wanted to determine the influence of total blood volume (BV) and blood lactate quantity on lactate concentrations during incremental exercise. Twenty-six healthy, nonsmoking, heterogeneously trained females (27.5 ± 5.9 ys) performed an incremental cardiopulmonary exercise test on a cycle ergometer during which maximum oxygen uptake (V·O2max), lactate concentrations ([La-]) and hemoglobin concentrations ([Hb]) were determined. Hemoglobin mass and blood volume (BV) were determined using an optimised carbon monoxide-rebreathing method. V·O2max and maximum power (Pmax) ranged between 32 and 62 mL·min-1·kg-1 and 2.3 and 5.5 W·kg-1, respectively. BV ranged between 81 and 121 mL·kg-1 of lean body mass and decreased by 280 ± 115 mL (5.7%, p = 0.001) until Pmax. At Pmax, the [La-] was significantly correlated to the systemic lactate quantity (La-, r = 0.84, p < 0.0001) but also significantly negatively correlated to the BV (r = -0.44, p < 0.05). We calculated that the exercise-induced BV shifts significantly reduced the lactate transport capacity by 10.8% (p < 0.0001). Our results demonstrate that both the total BV and La- have a major influence on the resulting [La-] during dynamic exercise. Moreover, the blood La- transport capacity might be significantly reduced by the shift in plasma volume. We conclude, that the total BV might be another relevant factor in the interpretation of [La-] during a cardio-pulmonary exercise test.

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We sought to determine the effects of three treatments on hemoglobin (Hb) levels in patients with chronic mountain sickness (CMS): 1) descent to lower altitude, 2) nocturnal O2 supply, 3) administration of acetazolamide. Nineteen patients with CMS living at an altitude of 3,940 ± 130 m participated in the study, which consisted of a 3-wk intervention phase and a 4-wk postintervention phase. Six patients spent 3 wk at an altitude of 1,050 m (low altitude group, LAG), six received supplemental oxygen for 12 h overnight (oxygen group, OXG), and seven received 250 mg of acetazolamide daily (acetazolamide group, ACZG). Hemoglobin mass (Hbmass) was determined using an adapted carbon monoxide (CO) rebreathing method before, weekly during, and 4 wk postintervention. Hbmass decreased by 245 ± 116 g (P < 0.01) in the LAG and by 100 ± 38 g in OXG, and 99 ± 64 g in ACZG (P < 0.05, each), respectively. In LAG, hemoglobin concentration ([Hb]) decreased by 2.1 ± 0.8 g/dL and hematocrit by 7.4 ± 2.9% (both P < 0.01), whereas OXG and ACZG only trended toward lower values. Erythropoietin concentration ([EPO]) decreased between 81 ± 12% and 73 ± 21% in LAG at low altitude (P < 0.01) and increased by 161 ± 118% 5 days after return (P < 0.01). In OXG and ACZG, the [EPO] decrease was ∼75% and ∼50%, respectively, during the intervention (P < 0.01). Descent to low altitude (from 3,940 m to 1,050 m) is a fast-acting measure for the treatment of excessive erythrocytosis in patients with CMS, reducing Hbmass by 16% within 3 wk. Nighttime oxygen supplementation and daily acetazolamide administration are also effective, but reduce Hbmass by only 6%.NEW & NOTEWORTHY To our knowledge, this is the first study examining the effect of three different treatments [descending to lower altitude (from 3,900 m to 1,050 m), nocturnal oxygen supply, and administration of acetazolamide] on changes in hemoglobin mass in patients experiencing chronic mountain sickness (CMS). We report that descent to low altitude is a fast-acting measure for the treatment of excessive erythrocytosis in patients with CMS, reducing Hbmass by 16% within 3 wk. Nighttime oxygen supplementation and daily acetazolamide administration are also effective, but reduce Hbmass by only 6%. In all three treatments, the underlying mechanism is a reduction in plasma erythropoietin concentration due to higher oxygen availability.

Asunto(s)

Mal de Altura , Eritropoyetina , Policitemia , Humanos , Mal de Altura/tratamiento farmacológico , Policitemia/tratamiento farmacológico , Altitud , Acetazolamida/uso terapéutico , Eritropoyetina/uso terapéutico , Hemoglobinas , Oxígeno

RESUMEN

PURPOSE: To investigate the value of red blood cell parameters in Myelodysplastic syndrome (MDS) diagnosis and their relations to MDS subtypes and risk groups. METHODS: The red blood cell parameter [mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC) and red cell distribution width (RDW)] levels [203 MDS, 99 aplastic anemia (AA), 145 megaloblastic anemia (MA)] were collected from a single-center retrospective cohort. The cut-off values, area under the receiver operating characteristic curve (ROC) curve (AUC), sensitivity and specificity of the four parameters were calculated from the ROC. Furthermore, Kruskal-Wallis test and Dunn's Test were performed to determine erythrocyte parameters in different subtypes and prognostic risks MDS. RESULTS: There are significant statistic differences in RDW (P < 0.001), MCH (P = 0.036) and MCHC (P < 0.001) (MDS vs AA); RDW (P = 0.009), MCV (P < 0.001), MCH (P < 0.001) and MCHC (P = 0.001) (MDS vs MA); MCV (P = 0.011) and MCH (P = 0.008) (higher-risk MDS vs lower-risk MDS). Between MDS and MA, the area under the receiver operating characteristic curve (ROC) curve (AUC) values of MCV, MCH, MCHC, RDW were 0.846, 0.855, 0.617, and 0.593. Between MDS and AA, the AUC values of MCH, MCHC, RDW were 0.609, 0.671, and 0.662, respectively. CONCLUSIONS: The red blood cell parameters contribute to the differential diagnosis of MDS, AA and MA and are related to MDS subtypes and risk groups.

Asunto(s)

Eritrocitos , Síndromes Mielodisplásicos , Humanos , Estudios Retrospectivos , Índices de Eritrocitos , Síndromes Mielodisplásicos/diagnóstico , Pronóstico

RESUMEN

BACKGROUND: We aimed to evaluate dynamic alterations in cerebral total hemoglobin concentration (HbT) in individuals with orthostatic hypotension (OH) and orthostatic intolerance (OI) symptoms using a portable near-infrared spectroscopy (NIRS) system. METHODS: Participants comprised 238 individuals (mean age, 47.9 years) without a history of cardiovascular, neurodegenerative, or cerebrovascular diseases, including those with unexplained OI symptoms and healthy volunteers. Participants were categorized by the presence of OH based on the supine-to-stand blood pressure (BP) drop and OI symptoms using on OH questionnaires: classic OH (OH-BP), OH symptoms alone (OH-Sx), and control groups. Random case-control matching sets were constructed, resulting in 16 OH-BP and 69 OH-Sx-control sets. The time-derivative of HbT change in the prefrontal cortex during the squat-to-stand maneuver was measured using a portable NIRS system. RESULTS: There were no differences in demographics, baseline BP, and heart rate among matched sets. The peak time of maximum slope variation in HbT change, indicating the recovery rate and speed of cerebral blood volume (CBV) change, was significantly longer in OH-Sx and OH-BP groups than in the control group under transition to a standing position after squatting. In the OH-BP subgrouping, the peak time of maximum slope variation in HbT change was significantly longer only in OH-BP with OI symptoms, but did not differ between OH-BP without OI symptoms and controls. CONCLUSIONS: Our results suggest that OH and OI symptoms are associated with dynamic alterations in cerebral HbT. Regardless of the severity of the postural BP drop, OI symptoms are associated with prolonged CBV recovery.

Asunto(s)

Sistema Cardiovascular , Hipotensión Ortostática , Intolerancia Ortostática , Humanos , Persona de Mediana Edad , Hipotensión Ortostática/diagnóstico , Presión Sanguínea/fisiología , Espectroscopía Infrarroja Corta , Hemodinámica

RESUMEN

According to the ICH S3A Q&A, microsampling is applicable to pharmaceutical drugs and toxicological analysis. Few studies have reported the effect of microsampling on the toxicity of immunotoxicological drugs. The aim of this multicenter study was to evaluate the toxicological effects of serial microsampling on rats treated with azathioprine as a model drug with immunotoxic effects. Fifty microliters of blood were collected from the jugular vein of Sprague-Dawley rats at six time points from day 1 to 2 and 7 time points from day 27 to 28. The study was performed at three organizations independently. The microsampling effect on clinical signs, body weights, food consumption, hematological parameters, biochemical parameters, urinary parameters, organ weights, and tissue pathology was evaluated. Azathioprine-induced changes were observed in certain hematological and biochemical parameters and thymus weight and pathology. Microsampling produced minimal or no effects on almost all parameters; however, at 2 organizations, azathioprine-induced changes were apparently masked for two leukocytic, one coagulation, and two biochemical parameters. In conclusion, azathioprine toxicity could be assessed appropriately as overall profiles even with blood microsampling. However, microsampling may influence azathioprine-induced changes in certain parameters, especially leukocytic parameters, and its usage should be carefully considered.

RESUMEN

Objective: The optimal red blood cell transfusion strategy for children remains unclear. We developed an individualized red blood cell transfusion strategy for children and tested the hypothesis that transfusion guided by this strategy could reduce blood exposure, without increasing perioperative complications in children. Methods: In this randomized controlled clinical trial, 99 children undergoing noncardiac surgeries who had blood loss of more than 20% total blood volume were randomly assigned to an individualized-strategy group using Pediatric Perioperative-Transfusion-Trigger Score or a control group. The amount of transfused red blood cell was counted, and patients were followed up for postoperative complications within 30 days. Results: Twenty-six children (53.1%) in the individualized-strategy group received transfusion perioperatively, as compared with 37 children (74%) in the control group (p < 0.05). During surgery, children in the individualized-strategy group were exposed to fewer transfusions than in the control group (0.87±1.03 vs 1.33±1.20 Red-Blood-Cell units per patient, p = 0.02). The incidence of severe complications in the individualized-strategy group had a lower trend compared to the control group (8.2% vs 18%, p = 0.160). No significant difference was found in the other outcomes. Conclusion: This trial proved that red blood cell transfusion guided by the individualized strategy reduced perioperative blood exposure in children, without increasing the incidence of severe complications. This conclusion needs to be reaffirmed by larger-scale, multicenter clinical trials.