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1.

Introduction

This systematic review examines the relationship between blood loss and clinical signs and explores its use to trigger clinical interventions in the management of obstetric haemorrhage.

Methods

A systematic review of the literature was carried out using a comprehensive search strategy to identify studies presenting data on the relationship of clinical signs & symptoms and blood loss. Methodological quality was assessed using the STROBE checklist and the general guidelines of MOOSE.

Results

30 studies were included and five were performed in women with pregnancy-related haemorrhage (other studies were carried in non-obstetric populations). Heart rate (HR), systolic blood pressure (SBP) and shock index were the parameters most frequently studied. An association between blood loss and HR changes was observed in 22 out of 24 studies, and between blood loss and SBP was observed in 17 out of 23 studies. An association was found in all papers reporting on the relationship of shock index and blood loss. Seven studies have used Receiver Operating Characteristic Curves to determine the accuracy of clinical signs in predicting blood loss. In those studies the AUC ranged from 0.56 to 0.74 for HR, from 0.56 to 0.79 for SBP and from 0.77 to 0.84 for shock index. In some studies, HR, SBP and shock index were associated with increased mortality.

Conclusion

We found a substantial variability in the relationship between blood loss and clinical signs, making it difficult to establish specific cut-off points for clinical signs that could be used as triggers for clinical interventions. However, the shock index can be an accurate indicator of compensatory changes in the cardiovascular system due to blood loss. Considering that most of the evidence included in this systematic review is derived from studies in non-obstetric populations, further research on the use of the shock index in obstetric populations is needed.  相似文献   

2.

Introduction

Given the severity of the current imbalance between blood donor supply and recipient demand, discarded blood drawn from the routine venesections of haemochromatosis (HFE-HH) patients may serve as a valuable alternative source for blood banks and transfusion. We investigated whether functional or biochemical differences existed between HFE-HH and control blood samples, with particular focus upon the haemorheological properties, to investigate the viability of venesected blood being subsequently harvested for blood products.

Methods

Blood samples were collected from HFE-HH patients undergoing venesection treatment (n = 19) and healthy volunteers (n = 8). Moreover, a second experiment investigated the effects of a dose-response of iron (0, 40, 80, 320 mM FeCl3) on haemorheology in healthy blood samples (n = 7). Dependent variables included basic haematology, iron status, haematocrit, red blood cell (RBC) aggregation (native and standardised haematocrit) and “aggregability” (RBC tendency to aggregate in a standard aggregating medium; 0.4 L/L haematocrit in a Dx70), and RBC deformability.

Results

Indices of RBC deformability were significantly decreased for HFE-HH when compared with healthy controls: RBC deformability was significantly decreased at 1–7 Pa (p < 0.05), and the shear stress required for half maximal deformability was significantly increased (p < 0.05) for HFE-HH. RBC aggregation in plasma was significantly increased (p < 0.001) for HFE-HH, although when RBC were suspended in plasma-free Dx70 no differences were detected. No differences in RBC deformability or RBC aggregation/aggregability were detected when healthy RBC were incubated with varying dose of FeCl3.

Conclusion

HFE-HH impairs the haemorheological properties of blood; however, RBC aggregability was similar between HFE-HH and controls when cells were suspended in a plasma-free medium, indicating that plasma factor(s) may explain the altered haemorheology in HFE-HH patients. Acute exposure to elevated iron levels does not appear (in isolation) to account for these differences. Further consideration is required prior to utilising routine venesection blood for harvesting RBC concentrates due to the potential risk of microvascular disorders arising from impaired haemorheology.  相似文献   

3.

Background

Intraoperative blood salvage, an effective blood conservation strategy, has not been applied in onco-surgery, because of potential malignant cell contamination. In this study we tested effectiveness of a modified leukocyte depletion filter (M-LDF) for removal of tumor cells.

Materials and Methods

The effects of M-LDF and regular LDF on removal of cells (HepG2 cell line) were compared. The safety of M-LDF was tested with blood (collected and washed during onco-surgery), the salvaged blood mixed with tumor cells from the solid tumor of the same patient, or mixed with HepG2 cells (n=30 in each protocol). Cancer cells were identified by flow cytometry, culture and bioassay with and without filtration.

Results

M-LDF removed 5-log of HepG2 and nucleated cells, which was much higher than regular LDF, and cells were destroyed when they passed through M-LDF. Cytokeratin-positive cells in all samples were removed by M-LDF. Invasive growth adherent cells were found in most of unfiltered samples and 67% of the inoculated nude mice developed tumors in LDF-treated sample. Neither adherent cells nor nude mice developed tumors were found in M-LDF-treated samples.

Discussion and Conclusion

Since M-LDF can effectively remove and destroy cancer cells in the salvaged blood, it has great potential for clinical application.  相似文献   

4.
The influence of omega-3 polyunsaturated fatty acids (omega-3 PUFA) on the activity of glutathione reductase, glutathione transferase and glutathione peroxidase in the liver cytosole and red blood cells of normal rats and animals with experimental chronic bronchitis. omega-3 PUFA ("Tekom" medication) activate glutathione reductase of liver cytosole and glutathionperoxidase in the red blood cells in rats. In the rats with chronic inflammatory process in bronchia omega-3 PUFA corrects the glutathione-dependent systems of detoxication. Effects were more expressed in the liver cytosole in comparison with the red blood cells. The using of omega-3 PUFA as a means for treatment and prophylaxis was more effective than for treatment only.  相似文献   

5.

Background

Preliminary studies in chronic fatigue syndrome (CFS) patients and XMRV infected animals demonstrated plasma viremia and infection of blood cells with XMRV, indicating the potential risk for transfusion transmission. XMRV and MLV-related virus gene sequences have also been detected in 4–6% of healthy individuals including blood donors in the U.S. These results imply that millions of persons in the U.S. may be carrying the nucleic acid sequences of XMRV and/or MLV-related viruses, which is a serious public health and blood safety concern.

Methodology/Principal Findings

To gain evidence of XMRV or MLV-related virus infection in the U.S. blood donors, 110 plasma samples and 71 PBMC samples from blood donors at the NIH blood bank were screened for XMRV and MLV-related virus infection. We employed highly sensitive assays, including nested PCR and real-time PCR, as well as co-culture of plasma with highly sensitive indicator DERSE cells. Using these assays, none of the samples were positive for XMRV or MLV-related virus.

Conclusions/Significance

Our results are consistent with those from several other studies, and demonstrate the absence of XMRV or MLV-related viruses in the U.S. blood donors that we studied.  相似文献   

6.
The properties of the enzyme in the serum of blood group B individuals that catalyses the transfer of small amounts of N-acetyl-D-galactosamine to H-active precursor structures were compared with those of the blood group B gene-associated alpha-(1----3)-D-galactosyltransferase and with the blood group A gene-associated alpha-(1----3)-N-acetyl-D-galactosaminyltransferases in the serum of blood group A1 and A2 individuals. The biosynthetic products formed by the enzyme in B serum were identical with the A-active structures synthesised by the A1 and A2 gene-associated alpha-(1----3)-N-acetyl-D-galactosaminyltransferases but the enzyme differed from the A1 and A2 transferases in its apparent Km for UDP-N-acetyl-D-galactosamine, its heat susceptibility, its failure to bind to Sepharose 4B, and its adsorption to H-active sites on group O red cell ghosts under conditions which bind the B transferase but fail to adsorb the A1 and A2 transferases. The correlation between the levels of alpha-(1----3)-D-galactosyltransferase and alpha-(1----3)-N-acetyl-D-galactosaminyltransferase activities in all the group B serum samples tested, the maintenance of the same ratio of activities after successive cycles of binding to group O red cell ghosts, the retention of the ability to convert blood group O to A-active cells after treatment of the serum with Sepharose 4B, and the failure to detect any comparable activity in group O serum samples tested under the same conditions indicated that the enzyme in group B serum that utilises UDP-N-acetyl-D-galactosamine to make blood group A-active structures is the B gene-associated alpha-(1----3)-D-galactosyltransferase.  相似文献   

7.
8.

Background

Blood culture contamination in emergency departments (ED) that experience a high volume of patients has negative impacts on optimal patient care. It is therefore important to identify risk factors associated with blood culture contamination in EDs.

Methodology/Principal Findings

A prospectively observational study in a university-affiliated hospital were conducted between August 2011 and December 2012. Positive monomicrobial and negative blood cultures drawn from adult patients in the ED were analyzed to evaluate the possible risk factors for contamination. A total of 1,148 positive monomicrobial cases, 391 contamination cases, and 13,689 cases of negative blood culture were identified. Compared to patients with negative blood cultures, patients in triage levels 1 and 2 (Incidence Rate Ratio, IRR = 2.24), patients with end-stage renal disease (ESRD) (IRR = 2.05), and older patients (IRR: 1.02 per year) were more likely to be associated with ED blood culture contamination.

Conclusions/Significance

Critical patients (triage levels 1 and 2), ESRD patients, and older patients were more commonly associated with blood culture contamination in the ED. Further studies to evaluate whether the characteristics of skin commensals contribute to blood culture contamination is warranted, especially in hospitals populated with high-risk patients.  相似文献   

9.
Smad3基因剔除对小鼠造血功能的影响   总被引:1,自引:0,他引:1  
研究Smad3基因剔除对小鼠造血功能的影响。实验小鼠分为 5组 ,每组有Smad3基因剔除小鼠(Smad3 - - )和其同窝孪生的野生型小鼠 (Smad3 + + )各 1只。小鼠的造血功能用 14天形成的脾结节 (CFU S1 4 )、多系祖细胞 (CFU GEMM)、粒 单系祖细胞 (CFU GM)、红系祖细胞 (BFU E)测定及外周血象、骨髓象等实验血液学指标来确定。每组小鼠取尾血作白细胞、红细胞和血小板计数 ,涂片作白细胞分类计数。将一侧股骨的骨髓冲出 ,制成单细胞悬液 ,计数其中有核细胞数 ,测定CFU GM、BFU E、CFU GEMM值。将每只小鼠的 4× 10 4个骨髓有核细胞 ,经尾静脉注入 3只 8~ 10周经致死量射线照射的同系雌性小鼠体内 ,测定 14天的CFU S。取一部分胸骨、肝脏、脾脏固定做病理切片 ,其余胸骨冲出骨髓 ,涂片作分类计数。结果Smad3 - - 小鼠外周血白细胞和血小板计数明显高于Smad3 + + 小鼠 ,红细胞数无显著差异。外周血白细胞分类结果也表明粒细胞显著增高。骨髓有核细胞数无显著差异 ,CFU GM显著增高 ,BFU E无显著差异 ,CFU GEMM明显减少 ,CFU S显著减少。病理形态学观察发现骨髓增生极度活跃 ,以粒系为主 ,肝脾无显著差别。骨髓涂片分类表明粒系增多 ,粒系 :红系比例增高。因此得出结论Smad3基因剔除使小鼠造血干祖细胞数目  相似文献   

10.
The dorsal and median raphe nuclei in rats were electrically stimulated and blood pressure and heart rate were recorded. Stimulation of each raphe nucleus caused an increase in blood pressure without affecting heart rate. The size of the increase in blood pressure depended upon the stimulus-intensity.Significant increases were already obtained with 5 sec. trains of 0.3 msec., 200 μA stimuli given at a frequency of 50 Hz. The increases in blood pressure could be obtained with electrodes within the raphe nuclei.Pretreating rats with para-chlorophenylalanine (pCPA, 100 mg/kg.day for 3 days) significantly diminished the increases in blood pressure obtained during electrical stimulation of the median raphe nucleus. However, similar pretreatment did not affect blood pressure rises induced by dorsal raphe stimulation.These data are discussed in relation to the role of central serotoninergic mechanisms in cardiovascular control.  相似文献   

11.
Some factors controlling the distribution of Na275SeO3 in sheep blood were studied in vitro. After centrifuging Na275SeO3-incubated blood most of the radioactivity was found in the plasma. The labelling of plasma protein by 75Se was dependent on the presence of erythrocytes. The degree of labelling of plasma protein increased with erythrocyte concentration. When phosphate-buffered saline-washed erythrocytes were suspended in phosphate-buffered saline and incubated with Na275SeO3 the majority of the 75Se was detected in the erythrocytes. On incubating these labelled erythrocytes with unlabelled plasma there was a transfer of radioactivity to the plasma. The calculated activation energy for the labelling of plasma was 107.52 kJ/mol. Albumin was shown not to be a principal acceptor of 75Se from the erythrocytes by ammonium sulphate precipitation of radioactive plasma. Addition of Na2SeO3 to the labelled blood resulted in the transfer of 75Se from plasma to the erythrocytes. Radioactive plasma incubated at 37 degrees C was thermolabile with respect to its 75Se content whereas in whole blood the degree of 75Se binding to plasma protein did not vary suggesting that a recycling of selenium was occurring in blood. From the results presented an in vitro model of selenium metabolism in blood is postulated.  相似文献   

12.
Blood volume changes in the fetal lung following the onset of ventilation were studied by isotopic measurement of red blood cell and plasma volume in rapidly frozen lungs of ten near term fetal lambs. Total pulmonary blood volumes of fetal lambs ventilated with 3% O2 and 7% CO2 in nitrogen (so that blood gas levels were little changed from fetal values), or with air, were compared with measurements in unventilated lambs. Regional correlations of blood volume and blood flow (measured with isotope-labeled microemboli) within the lungs were also examined. Total pulmonary blood volume averaged 5.6 ml/kg body weight in unventilated fetal lambs and was approximately 43% greated in fetal lambs after 5-20 min of air ventilation, but not significantly different in lambs ventilated with 3% O2 and 7% CO2 in nitrogen. Thus it is ventilation with air, rather than the introduction of gas into the alveoli, which enlarges the fetal pulmonary vascular bed. Regional pulmonary blood volume and blood flow were correlated, though poorly, in air-ventilated lungs, but not in lungs ventilated with 3% O2 and 7% CO2 in nitrogen; this suggests that a common factor may operate to increase both blood flow and blood volume in the fetal lung following the introduction of air.  相似文献   

13.

Background

Leptospirosis is a neglected zoonosis of ubiquitous distribution. Symptoms are often non-specific and may range from flu-like symptoms to multi-organ failure. Diagnosis can only be made by specific diagnostic tests like serology and PCR. In non-endemic countries, leptospirosis is often not suspected before antibiotic treatment has been initiated and consequently, relevant samples for diagnostic PCR are difficult to obtain. Blood cultures are obtained from most hospitalized patients before antibiotic therapy and incubated for at least five days, thus providing an important source of blood for PCR diagnosis. However, blood cultures contain inhibitors of PCR that are not readily removed by most DNA-extraction methods, primarily sodium polyanetholesulfonate (SPS).

Methodology/Principal Findings

In this study, two improved DNA extraction methods for use with blood cultures are presented and found to be superior in recovering DNA of Leptospira interrogans when compared with three previously described methods. The improved methods were easy and robust in use with all tested brands of blood culture media. Applied to 96 blood cultures obtained from 36 patients suspected of leptospirosis, all seven patients with positive convalescence serology were found positive by PCR if at least one anaerobic and one aerobic blood culture, sampled before antibiotic therapy were tested.

Conclusions/Significance

This study suggests that a specific and early diagnosis can be obtained in most cases of severe leptospirosis for up to five days after initiation of antimicrobial therapy, if PCR is applied to blood cultures already sampled as a routine procedure in most septic patients.  相似文献   

14.
Application of the artificial endocrine pancreas in 12 patients undergoing total duodenopancreatectomy and 3 diabetics in whom different operations were performed proved to be safe for the patients with respect to blood glucose control and prevention of ketosis. In the postoperative period, essentially normal blood glucose values were obtained despite high caloric parenteral nutrition.  相似文献   

15.
Different methodologies for the measurement of peptide amino acid (PAA) in blood and plasma were compared in sheep. Preparation of blood and plasma samples consisted of a deproteinization, either chemical with sulfosalicylic acid (0.04 g for 1 ml of sample) or physical by ultrafiltration (10,000‐MW cut‐off filters), with or without a subsequent ultrafiltration through a 3,000‐MW cut‐off filter. Peptide concentrations were determined by quantification of amino acid concentrations before and after acid hydrolysis of samples. Free amino acid concentrations were similar by all the method used (about 2.5 and 2.7mM, for blood and plasma respectively). Peptide concentrations were higher with chemical deproteinization (10.6 and 4.2 mM, for blood and plasma respectively) than with physical deproteinization (5.7 and 3.3 mM, for blood and plasma respectively). When the deproteinized samples were further treated to remove material of molecular weight above than 3 kDa, peptide concentrations were significantly reduced, which indicates inefficiencies in the ability of the deproteinizing procedures in removing all the proteinaceous materials. Concentration of small PAA (< 3kDa) in blood was about 1.5‐fold that in plasma, mainly due to peptide Gly and Glu derived from the hydrolysis of the erythrocyte glutathione. The choice of a methodology for quantifying circulating peptides is discussed.  相似文献   

16.

Background

Compartmentalization of HIV-1 between the genital tract and blood was noted in half of 57 women included in 12 studies primarily using cell-free virus. To further understand differences between genital tract and blood viruses of women with chronic HIV-1 infection cell-free and cell-associated virus populations were sequenced from these tissues, reasoning that integrated viral DNA includes variants archived from earlier in infection, and provides a greater array of genotypes for comparisons.

Methodology/Principal Findings

Multiple sequences from single-genome-amplification of HIV-1 RNA and DNA from the genital tract and blood of each woman were compared in a cross-sectional study. Maximum likelihood phylogenies were evaluated for evidence of compartmentalization using four statistical tests. Genital tract and blood HIV-1 appears compartmentalized in 7/13 women by ≥2 statistical analyses. These subjects'' phylograms were characterized by low diversity genital-specific viral clades interspersed between clades containing both genital and blood sequences. Many of the genital-specific clades contained monotypic HIV-1 sequences. In 2/7 women, HIV-1 populations were significantly compartmentalized across all four statistical tests; both had low diversity genital tract-only clades. Collapsing monotypic variants into a single sequence diminished the prevalence and extent of compartmentalization. Viral sequences did not demonstrate tissue-specific signature amino acid residues, differential immune selection, or co-receptor usage.

Conclusions/Significance

In women with chronic HIV-1 infection multiple identical sequences suggest proliferation of HIV-1-infected cells, and low diversity tissue-specific phylogenetic clades are consistent with bursts of viral replication. These monotypic and tissue-specific viruses provide statistical support for compartmentalization of HIV-1 between the female genital tract and blood. However, the intermingling of these clades with clades comprised of both genital and blood sequences and the absence of tissue-specific genetic features suggests compartmentalization between blood and genital tract may be due to viral replication and proliferation of infected cells, and questions whether HIV-1 in the female genital tract is distinct from blood.  相似文献   

17.
Li Q  Yu CH  Yu JH  Liu L  Xie SS  Li WW  Yang X  Fan WB  Gai ZT  Chen SJ  Kato N 《PloS one》2012,7(1):e29928

Background

Studies have observed an association between the ABO blood group and risk of certain malignancies. However, no studies of the association with hepatocellular carcinoma (HCC) risk are available. We conducted this hospital-based case-control study to examine the association with HCC in patients with chronic hepatitis B (CHB).

Methods

From January 2004 to December 2008, a total of 6275 consecutive eligible patients with chronic hepatitis B virus (HBV) infection were recruited. 1105 of them were patients with HBV-related HCC and 5,170 patients were CHB without HCC. Multivariate logistic regression models were used to investigate the association between the ABO blood group and HCC risk.

Results

Compared with subjects with blood type O, the adjusted odds ratio (AOR) for the association of those with blood type A and HCC risk was 1.39 [95% confidence interval (CI), 1.05–1.83] after adjusting for age, sex, type 2 diabetes, cirrhosis, hepatitis B e antigen, and HBV DNA. The associations were only statistically significant [AOR (95%CI) = 1.56(1.14–2.13)] for men, for being hepatitis B e antigen positive [AOR (95%CI) = 4.92(2.83–8.57)], for those with cirrhosis [AOR (95%CI), 1.57(1.12–2.20)], and for those with HBV DNA≤105copies/mL [AOR (95%CI), 1.58(1.04–2.42)]. Stratified analysis by sex indicated that compared with those with blood type O, those with blood type B also had a significantly high risk of HCC among men, whereas, those with blood type AB or B had a low risk of HCC among women.

Conclusions

The ABO blood type was associated with the risk of HCC in Chinese patients with CHB. The association was gender-related.  相似文献   

18.

Background

Rapid identification of the etiological agent in bloodstream infections is of vital importance for the early administration of the most appropriate antibiotic therapy. Molecular methods may offer an advantage to current culture-based microbiological diagnosis. The goal of this study was to evaluate the performance of IRIDICA, a platform based on universal genetic amplification followed by mass spectrometry (PCR/ESI-MS) for the molecular diagnosis of sepsis-related pathogens directly from the patient’s blood.

Methods

A total of 410 whole blood specimens from patients admitted to Emergency Room (ER) and Intensive Care Unit (ICU) with clinical suspicion of sepsis were tested with the IRIDICA BAC BSI Assay (broad identification of bacteria and Candida spp.). Microorganisms grown in culture and detected by IRIDICA were compared considering blood culture as gold standard. When discrepancies were found, clinical records and results from other cultures were taken into consideration (clinical infection criterion).

Results

The overall positive and negative agreement of IRIDICA with blood culture in the analysis by specimen was 74.8% and 78.6%, respectively, rising to 76.9% and 87.2% respectively, when compared with the clinical infection criterion. Interestingly, IRIDICA detected 41 clinically significant microorganisms missed by culture, most of them from patients under antimicrobial treatment. Of special interest were the detections of one Mycoplasma hominis and two Mycobacterium simiae in immunocompromised patients. When ICU patients were analyzed separately, sensitivity, specificity, positive and negative predictive values compared with blood culture were 83.3%, 78.6%, 33.9% and 97.3% respectively, and 90.5%, 87.2%, 64.4% and 97.3% respectively, in comparison with the clinical infection criterion.

Conclusions

IRIDICA is a promising technology that offers an early and reliable identification of a wide variety of pathogens directly from the patient’s blood within 6h, which brings the opportunity to improve management of septic patients, especially for those critically ill admitted to the ICU.  相似文献   

19.
Combinations of thrombopoietin and cytokines that act on megakaryocyte development (stem cell factor, IL3, IL6, IL11, flt3 ligand (now known as FLT3LG), erythropoietin, GM-CSF and G-CSF were evaluated for their ability to enhance clonal growth in vitro of X-irradiated CD34(+) megakaryocytic progenitor cells (CFU-megakaryocytes) purified from normal human peripheral blood. These data were compared with corresponding results described previously for CD34(+) CFU-megakaryocytes from human placental/umbilical cord blood (I. Kashiwakura, Radiat. Res. 153, 144-152, 2000). All cytokines, except IL3, promoted thrombopoietin-induced colony formation, but they resulted in exponential radiation survival curves. No significant differences in the D(0) (46-61 cGy) and extrapolation number n (1.00-1.04) were observed between thrombopoietin alone and in combination with these cytokines. IL3 did not promote colony formation, but marked shoulders were observed on the survival curves (D(0) = 91 cGy, n = 2.83). Flow cytometric analysis of cells harvested from cultures of X-irradiated cells stimulated with thrombopoietin plus IL3 showed no significant differences in the expression of surface antigens and DNA ploidy distribution of megakaryocytes from the control. These findings suggest that IL3 plays a key role in promoting the survival of X-irradiated CD34(+) CFU-megakaryocytes from peripheral blood as well as those from cord blood, though the former are more radiosensitive.  相似文献   

20.
On day 14 of the oestrous cycle in swine, laparotomy under general anaesthesia was performed and both ovaries with their ovarian pedicles and with part of the uterine horns were isolated using ligatures and excised as two independent units which were called A and B. They were placed in separate aluminium paper boxes on a heated surface (40°C). Preparation A was supplied with autologous arterial blood through the uterine artery and through the ovarian artery. The mesosalpinx of this preparation covered the ovary of preparation B from which the mesosalpinx was excised. Preparation B was also supplied with autologous blood through the ovarian artery. Tritiated prostaglandin F-2α (3H-PGF-2α) was injected into the musculature of the uterine horn of preparation A and then both preparations were perfused with blood of the same animal for 30 min. 3H-PGF-2α was found in the ovarian venous blood, interstitial fluid, and ovarian and pedicle tissue of preparation B. The data indicate an extravascular penetration of 3H-PGF-2α into the ovary through the mesosalpinx.  相似文献   

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