The effect of container material, storage time and temperature on cadmium and lead levels in heparinized human whole blood

The effect of container material (polycarbonate, polyethylene, polypropylene, polystyrene, borosilicate glass and Pyrex glass), storage time (0, 1, 3, 6, 13, 20, 28 and 60 days), and temperature (22 degrees C, 4 degrees C and -10 degrees C) on cadmium and lead levels in heparinized human whole blood was studied using graphite furnace atomic absorption spectrophotometry. Whole blood samples stored in polycarbonate containers at -10 degrees C did not show significant change in the concentrations of cadmium and lead up to 60 days. Also, the cadmium and lead levels remained unchanged for two weeks when the samples were stored in polyethylene and polypropylene vessels at 4 degrees C.     

The effects of storage conditions on the stability of carbon monoxide in postmortem blood

The stability of carbon monoxide (CO) in blood was studied under various conditions of storage using both spectrophotometric and gas chromatographic-flame ionization detector (GC-FID) methods of analysis. Changes (losses) in percent carbon monoxide saturation occurred under some conditions but not under others. Various mechanisms for CO losses are considered and one (passive diffusion of CO gas) best explains these observations. Losses of up to 60% of the original saturation occurred when blood was kept in uncapped containers at room temperature for 2 1/2 weeks or at 4 degrees C for 3 weeks. However, no changes occurred when blood was kept in tightly sealed containers for at least 4 months at either temperature.     

Unleaded gasoline use and lead level change in human blood

Rapid economic development and industrialization has been accompanied by an increase of energy consumption and environmental pollution. The consumption of gasoline has increased in general. However, the use of leaded gasoline has continuously decreased since 1988 in Korea. The Health Surveillance Project was launched in Korea in 1980, which questioned symptoms based on questionnaires and medical examinations from residents in the vicinity of 13 industrial areas and 2 non-industrial areas. 10,598 persons living in these 15 areas had medical checkups and donated their blood for heavy metal analysis from 1980 to 2000 through this project. Especially, the lead levels in participants’ blood of these areas were determined and monitored. Finally 4,967 samples in target areas were used to review the trend of lead level in blood in this paper. Ranges of lead concentrations by areas were from 15.2 to 21.0 μg/dL in 1981 and 22.3 to 34.3 μg/dL in 1988, but were 8.8 to 11.1 μg/dL in 1992 and 4.4 to 4.8 μg/dL in 1995. The consumption of leaded gasoline was at a peak in 1988. Blood lead level showed a very close relationship with the consumption rate of leaded gasoline in the change pattern (p<0.01) and showed a clear declining trend since the use of unleaded gasoline, especially from 1988, the year of Seoul Olympic game (ex, the blood lead levels were 15.2 μg/dL in 1981, 20.2 μg/dL in 1985, 24.3 μg/dL in 1988 and 3.9 μg/dL in 1993 in Yochon area). China also showed an decreasing trend of blood lead levels of the general population since the end of 1990s, when lead free gasoline was provided to China.     

储存条件对丙戊酸钠血药浓度测定的影响研究

目的考察两种储存条件对丙戊酸钠血药浓度测定结果的影响。方法取服用丙戊酸钠患者的全血标本分别在冬季室温(12℃)和冰箱冷藏(4℃)储存,用高效液相色谱法测定0、24、48、72 h时丙戊酸钠血药浓度。结果全血标本在两种储存条件下72 h内,丙戊酸钠的血药浓度无显著性变化(RSD<10%)。结论丙戊酸钠全血标本在室温(12℃)和冰箱冷藏(4℃)储存72 h保持稳定,不影响测定结果。     

西罗莫司在全血中的稳定性

目的:考察西罗莫司在全血中的稳定性.方法:配制浓度分别为2.5,7.5,22.5μg·L-1的西罗莫司血样,在3种温度下(25℃,4℃,-20℃)避光储存0～8 d和在-40℃存放后经历3个冻融周期,考察西罗莫司在全血中的稳定性.结果:在3种温度下储存8d和经历3个冻融周期后,西罗莫司血药浓度无显著变化.结论:西罗莫司血样可在冰冻或室温条件保存8d,经历3个冻融周期后西罗莫司在全血中仍能保持稳定.     

Elevation of lead in human blood from its controlled ingestion in beer.

1. Nine volunteers ingested high levels of lead in beer over a 28-d period. The increase in blood lead varied by a factor of about two. There was a similar two-fold variability in the whole-body uptake (mean 14%) of a single oral dose of the short-lived tracer 203Pb. 2. The average elevations led to estimates of the potential increment from consumption of alcoholic beverages which accord broadly with epidemiological observation and which, if relevant to intakes of lead in table wine, raise the possibility of considerably elevated levels in the blood of avid consumers. 3. Rate constants inferred for removal of stable lead from blood were lower than reported following intake of the tracer, reflecting feedback of lead from other compartments.     

The effect of storage upon cyanide in blood samples

CDPA blood of human origin was 'spiked' with a solution of potassium cyanide at four different concentrations. When such blood was left in contact with the atmosphere for up to 10 min an appreciable amount of the cyanide was lost. Stoppered tubes containing the 'spiked' blood were stored at -20 degrees C and 4 degrees C for up to 6 months. Most samples, especially those 'spiked' at the highest concentrations, showed a loss of cyanide.     

羟基喜树碱脂质体血中的稳定性考察

目的：考察脂质体对羟基喜树碱α-羟基内酯环结构的保护作用。方法：全血中分别加入羟基喜树碱脂质体、羟基喜树碱内酯溶液和羟基喜树碱羧酸盐溶液，12h内定时取样，采用高效液相色谱（HPLC）法测定。结果：12h脂质体包裹的羟基喜树碱在全血中的闭环率大于60．28%；而未包裹的羟基喜树碱的闭环率仅为32．24%。结论：脂质体对羟基喜树碱结构具有较好的保护作用，能有效地保护羟基喜树碱的α-羟基内酯环。     

Ameliorative effects of curcumin against lead induced toxicity in human peripheral blood lymphocytes culture

Lead, a heavy metal and multifaceted toxicant, is well studied for its distribution and toxicity in ecosystem, yet there is no consensus on its amelioration by any synthetic or phytochemical compounds. Curcumin, a known antioxidant and dietary element, is a well-known herb, for its therapeutic uses and having a wide spectrum of its beneficial properties against several adverse effects. Hence, the current study was taken into consideration to evaluate the ameliorative effects of curcumin (3.87?μM, i.e. 1.43?μg/ml) against lead acetate (doses: 10^?6 M, i.e. 0.379?μg/ml and 10^?4 M, i.e. 37.9?μg/ml, durations: 24 h and 69 h) induced genotoxicity and oxidative stress in human peripheral blood lymphocyte cultures (PBLC). On one hand, antigenotoxic and antioxidative potentials of curcumin against lead were simultaneously evaluated by the array of genotoxicity and oxidative stress indices. The result postulated that lead acetate showed dose- and duration-dependent increase in both genotoxicity and oxidative stress whereas curcumin, when added along with lead acetate, showed the significant amelioration in all genotoxic and oxidative stress-related indices. The study indicated that, due to alteration in antioxidant defense system, there is an adverse genotoxic effect of lead. On the other hand, curcumin, a potent antidote, can protect chromatin material against lead -mediated genotoxicity by balancing the activity of antioxidant defense system.     

The stability of cannabis and its preparations on storage.

Solutions of pure cannabinoids, nine samples of herbal and two of resin cannabis (one freshly prepared) were stored in varying conditions for up to 2 years. Exposure to light (not direct sunlight) was shown to be the greatest single factos in loss of cannabinoids especially in solutions, which should therefore be protected from light during analytical and phytochemical operations. Previous claims that solutions in ethanol were stable have not been substantiated. The effect of temperature, up to 20 degrees, was insignificant but air oxidation did lead to significant losses. These could be reduced if care was taken to minimize damage to the glands which act as "well filled, well closed containers". Loss of tetrahydrocannabinol after exposure to light does not lead to an increase in cannabinol, but air oxidation in the dark does. It is concluded that carefully prepared herbal or resin cannabis or extracts are reasonably stable for 1 to 2 years if stored in the dark at room temperature.     

The stability of endogenous corticotrophin in rat blood in vitro

Endogenous corticotrophin is stable in blood in vitro for periods of up to 1 hr. at 4° and 22°, and in plasma for at least 24 hr. at —15°. Estimates of plasma corticotrophin concentration provide less consistent results than assays done on whole blood. The optimal conditions for storing blood prior to the determination of its corticotrophin concentration are discussed.     

Assessing the contribution from lead in mining wastes to blood lead

Lead has been recognized for years as an environmental pollutant of concern for young children. Nonetheless, many children in the United States still experience high body burdens of lead. Reducing exposure to lead must include an assessment of all potential sources of lead and a definition of routes of exposure. In this paper, the relationships between soil lead and blood lead concentrations in residents in communities with high soil lead concentrations resulting from past mining and ore processing (milling) activities are compared to those derived from studies in urban communities or communities with operating smelters. The impact of mine waste-derived lead in soil (usually in the form of lead sulfide) on blood lead is less than that for lead in soil derived from smelter, vehicle, or paint sources. Possible reasons for a reduced impact of lead sulfide on blood lead in children in mining communities include the following: lead from mining sources contributes less to lead in the immediate environment of children than lead from other sources; mine wastes typically are of larger particle size, which decreases the bioavailability of lead in the gastrointestinal tract; and lead sulfide is absorbed less in the gastrointestinal tract compared to other lead species. A reduced impact of mine waste-derived lead on blood lead may be important from a regulatory point of view. Expensive cleanup actions for lead-contaminated soils in mining communities based on acceptable soil lead concentrations derived from smelter or urban communities may be questionable in terms of reducing blood lead in children.     

Studies on the antigenic stability of hepatic triglyceride lipase in human postheparin plasma during long-term storage

The present study describes how to process human postheparin plasma (PHP) containing hepatic triglyceride lipase (HTGL) that is utilized as a standard material of HTGL for the quantification of HTGL mass in human plasma. The optimal storage conditions for PHP were established by monitoring the stability of HTGL molecules in PHP as an antigen, which was stored in the liquid, frozen, or lyophilized state, using purified human PHP-HTGL as the standard material and a commercial HTGL ELISA MARUPI kit, which is a direct sandwich enzyme-linked immunosorbent assay (ELISA). The HTGL ELISA MARUPI kit, for which the validity was confirmed by precision and dilution tests, showed that the immunoreactive mass of HTGL in lyophilized PHP remained stable for at least 12 months at a storage temperature of 4 degrees C or lower. These results indicate that lyophilized PHP stored at a temperature of less than 4 degrees C can be utilized as the standard material for the quantification of HTGL in human plasma using the HTGL ELISA MARUPI kit.     

The stability of lyophilized lipid/DNA complexes during prolonged storage

It is well known that excipients are required to protect nonviral vectors during the lyophilization process. The goal of this study is to describe the stability of lyophilized nonviral vector preparations on pharmaceutically relevant timescales and provide insight into the factors that govern long-term stability of vectors in the dried state. Lipid/DNA complexes were lyophilized in glucose, sucrose, or trehalose and stored for a period of up to 2 years at five different temperatures (-20, 4, 22, 40, 60 degrees C). We evaluated simultaneously the physico-chemical characteristics (size, zeta potential, ethidium bromide (EtBr) accessibility, supercoiled DNA content) and the ability of vector formulations to transfect COS-7 cells at different time intervals. In addition, a fluorescence assay was utilized to assess levels of ROS in the dried cake after storage. The physical state of each formulation was evaluated by determination of the glass transition temperature and residual moisture content, before and after storage. Results from our stability study show that a progressive degradation of lipid/DNA complexes occurs in terms of transfection rates, particle size, dye accessibility, and supercoil content, even when samples are stored at low temperatures (e.g., -20 degrees C). Furthermore, our preliminary results on the quantification of free radicals in rehydrated formulations emphasize the importance of developing strategies to prevent the formation of reactive oxygen species (ROS) during prolonged storage in the dried state.     

Bovine blood lead reference material

A protocol is described for the preparation and characterization of bovine blood lead (Pb) reference material (RM). Adult bovine animals are orally dosed with Pb as Pb(NO3)2, and blood is collected directly from the jugular vein into 5-mL evacuated, low-Pb glass tubes containing EDTA as anticoagulant. The blood is cooled to 4 degrees C for 24 h and frozen and stored at -20 degrees C. Over 400 RMs were prepared and certified for reference values (RV) since the inception in 1974 of the Childhood Blood Lead Proficiency Testing Program. Five reference laboratories employing blood Pb methods of various principles were used to certify the RV, representing the true value, of 5 representative RMs containing 6.4-54.0 micrograms Pb/mL. Intertube homogeneity was verified by reference laboratories determining blood Pb in 20 tubes of 150 tubes collected from each of the 5 representative RMs. Intratube homogeneity was verified by an internal laboratory determining Pb in 12 consecutive 10-microL samples from 5 mL of blood in each of 3 representative RMs. Pb was unchanged in 37 bovine blood Pb RMs containing EDTA as anticoagulant after storage at -20 degrees C for 32-48 months.