Comparative Study on the Supramolecular Assemblies Formed by Calixpyridinium and Two Alginates with Different Viscosities.

In this work, a comparative study on the supramolecular assemblies formed by calixpyridinium and two alginates with different viscosities was performed. We found that sodium alginate (SA) with medium viscosity (SA-M) had a better capability to induce aggregation of calixpyridinium in comparison with SA with low viscosity (SA-L) because of the stronger electrostatic interactions between calixpyridinium and SA-M. Therefore, the morphology of calixpyridinium-SA-M supramolecular aggregates was a compact spherical structure, while that of calixpyridinium-SA-L supramolecular aggregates was an incompact lamellar structure. As a result, adding much more amount of 1,3,6,8-pyrenetetrasulfonic acid tetrasodium salt to calixpyridinium-SA-M solution was required to achieve the balance of the competitive binding, and in comparison with calixpyridinium-SA-L supramolecular aggregates, calixpyridinium-SA-M supramolecular aggregates were more sensitive to alkali. However, for the same reason, in comparison with calixpyridinium-SA-M supramolecular aggregates, calixpyridinium-SA-L supramolecular aggregates were much more stable in water not only at room temperature but also at a higher temperature, and even in salt solution. Therefore, in comparison with calixpyridinium-SA-L supramolecular aggregates, calixpyridinium-SA-M supramolecular aggregates exhibited a completely opposite response to acid because of the generation of salt. Because SA is an important biomaterial with excellent biocompatibility, it is anticipated that this comparative study is extremely important in constructing functional supramolecular biomaterials.

A hyaluronidase/temperature dual-responsive supramolecular assembly based on the anionic recognition of calixpyridinium.

We have successfully constructed a supramolecular assembly based on the anionic recognition of calixpyridinium for the first time employing native biocompatible polysaccharide hyaluronan as the guest, which showed hyaluronidase-responsive disassembly and temperature-responsive morphological conversion from a nanosphere to a nanosquare upon increasing the temperature.

Molecular binding behavior of water-soluble calix[4]arenes with asymmetric 4,4'-bipyridinium guests in aqueous solution: regioselective recognition or not?

The molecular binding behavior of water-soluble calix[4]arenes (p-sulfonatocalix[4]arene (SC4A) and p-sulfonatothiacalix[4]arene (STC4A)) with two asymmetric 4,4'-bipyridinium guests (N-methyl-N'-adamantane carbomethyl-4,4'-bipyridinium dibromide (MVAd2+) and N-methyl-N'-(naphthalen-2-ylmethyl)-4,4'-bipyridinium bromide iodide (MVNp2+)) was systematically studied using NMR spectroscopy and microcalorimetry in a neutral aqueous solution. Either the methyl group or the adamantane moiety in MVAd2+ could enter into the SC4A and STC4A cavities, without regioselectivity. The STC4A cavity can also accommodate MVNp2+, either through incorporation of the methyl group or the naphthalene moiety, without regioselectivity. However, we were surprised to find that MVNp2+ could only be included within the SC4A cavity through incorporation of the methyl group, with regioselectivity, which is rare for a flexible host. Furthermore, both SC4A and STC4A can form stable inclusion complexes with the two investigated asymmetric 4,4'-bipyridinium guests, driven by very favorable enthalpy changes, and the thermodynamic origins of the host selectivities for MVAd2+ and MVNp2+ can be well explained through their binding modes. The finding of this novel regioselective recognition is promising for potential applications in the development of more sophisticated biomimetic materials.

Metabolite Modulation in Human Plasma in the Early Phase of Acclimatization to Hypobaric Hypoxia.

The exposure of healthy subjects to high altitude represents a model to explore the pathophysiology of diseases related to tissue hypoxia. We explored a plasma metabolomics approach to detect alterations induced by the exposure of subjects to high altitude. Plasma samples were collected from 60 subjects both on plain and at high altitude (5300 m). Metabolite profiling was performed by gas chromatography-mass spectrometry (GC-MS) and ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOFMS) in conjunction with univariate and multivariate statistical analyses. ELISA assays were further employed to measure the levels of several relevant enzymes together with perturbed metabolic pathways. The results showed that hypobaric hypoxia caused significant and comprehensive metabolic changes, as represented by significant changes of 44 metabolites and 4 relevant enzymes. Using MetaboAnalyst 3.0, it was found that several key metabolic pathways were acutely perturbed. In addition, 5 differentially expressed metabolites in pre-exposure samples from the acute mountain sickness-susceptible (AMS-S) group compared with those from the AMS-resistant (AMS-R) group are identified, which warrant further validation as potential predictive biomarkers for AMS-S individuals. These results provide new insights for further understanding the pathophysiological mechanism of early acclimatization to hypobaric hypoxia and other diseases correlated to tissue hypoxia.

A calixpyridinium-based supramolecular tandem assay for alkaline phosphatase and its application to ATP hydrolysis reaction.

We have successfully implemented the supramolecular tandem assay principle for the real-time, continuous, direct, and label-free monitoring of alkaline phosphatase activity through a fluorescence "switch-off" assay based on a novel calixpyridinium/dye reporter pair. Because several diseases can be preliminarily diagnosed in light of an abnormal level of alkaline phosphatase in serum, the application of tandem assays to selectively monitor alkaline phosphatase activity has feasible implications in disease diagnosis.

[Role of oxygen therapy in prevention of chronic mountain sickness].

OBJECTIVE: To explore the effect of prophylaxis on youth's chronic mountain sickness(CMS) who moved to an altitude of above 5 000 meters by long-term oxygen therapy (LTOT). METHODS: Ninety-six male youth stationed at 5 070 m, 5 200 m and 5 380 m took oxygen continuously by nasal cannula (LTOT group) every body per day. One year later, epidemiological survey were carried out according to the international CMS diagnostic criteria consist of examining right ventricle end-diastolic dimension (RVED), right ventricular anterior wall (RVAW), right ventricular outflow tract (RVOT), main pulmonary artery (MPA), left ventricular end systolic diameter (LVSD) by ultrasonic diagnostic apparatus, and blood test of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (gamma-GT), creatine kinase (CK), lactate dehydrogenase (LDH), superoxide dismutase (SOD), malondialdehyde (MDA), nitric oxide (NO), nitric-oxide synthase (NOS) blood oxygen saturation (SaQ2). Then, they were compared with 91 males in the same group stationed at the same altitude (without any interventions, control group). RESULTS: (1) The epidemiological survey showed that, SaO2 were increased significantly (P < 0.05) and the prevalence rate of CMS were decreased compared with that of control group (P < 0.05). (2) Echocardiography showed that SOD, NO, NOS were increased (P < 0.05 or 0.01) and LVSD, MPA had no significant difference compared with that of control group (P > 0.05). (3) Biochemical index showed that, SOD, NO, NOS were increased (P < 0.05 or 0.01), MDA, ALT, AST, LDH were decreased (P < 0.05 or 0.01) and gamma-GT, CK had no significant difference compared with that of the control group. CONCLUSION: At high altitude, LTOT can reduce lipid peroxidation, improve the important organ injuries caused by hypoxia and protect the mitochondria respiratory function and play an important role on the prevention of chronic mountain sickness.

[Effect of iptkalim on myocardial enzymes and free radicals metabolism with hypoxic pulmonary hypertension].

OBJECTIVE: To explore the effects of iptkalim on myocardial enzymes and free radicals metabolism with hypoxic pulmonary hypertension (HPH), in order to provide evidence for the mechanism of iptkalim on clinical treat. METHODS: 110 young men stayed at high altitude above 5 000 m were divided into iptkalim group (n = 74) and placebo group (n = 36), aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyltransferase (gamma-GT), creatine kinase (CK), lactate dehydrogenase (LDH), superoxide dismutase (SOD), malonaldehyde (MDA), nitric oxide(NO) and nitric oxide synthase(NOS) were detected before and after took medicines for 6 mouths. RESULTS: After took medication for 6 mouths, ALT, AST, gamma-GT, CK and LDH were reduced, SOD, NO, and NOS were increased, MDA were reduced, there were very significant difference (P < 0.05). CONCLUSION: Oxygen free radicals have taken part in the process of HPH, iptkalim have the effect of anti-peroxidation of lipid and protect myocardial cells stress injured by hypoxia which related with mitochondrial membrane and cell membrane's K(ATP) channel activation.

[Sperm DNA damage in young men working on the plateau].

OBJECTIVE: To investigate whether long working in the high-altitude area can damage sperm DNA in men. METHODS: We enlisted 51 service men stationed on the plateau in an observation group and another 53 living in the low-altitude area in a control group. We detected and compared the damages to sperm DNA in the semen samples from the two groups using single cell gel electrophoresis and the sperm chromatin dispersion test. RESULTS: The percentages of total, G1, G2 and G3 comet cells and abnormal sperm of the observation group were (5.56 +/- 3.98)%, (3.72 +/- 1.85)%, (1.57 +/- 1.07)%, (0.27 +/- 0.34)% and (16.59 +/- 12.07)%, respectively, before stationed on the plateau, but significantly increased at 6 months of plateau life ([11.15 +/- 8.59]%, [5.97 +/- 3.26]%, [3.83 +/- 2.13%, [1.35 +/- 1.53]% and [22.03 +/- 15.33]%, P<0.05). The percentages of G2 comet cells and abnormal sperm were decreased to (3.32 +/- 1.83)% and (20.54 +/- 15.52)% at 12 months, but still significantly higher than the baseline (P<0.05). CONCLUSION: Long working on the plateau may damage sperm DNA, but its influence on male fertility deserves further investigation. Therefore, it is important to reinforce reproductive health protection for males working on the plateau.

[Changes of VEGF, TNF-alpha, IL-6 and NO in serum of patients with HAPE].

OBJECTIVE: To explore the possible pathophysiological process and mechanisms underlying the development and formation of high altitude pulmonary edema(HAPE) by observing the changes in contents of VEGF, TNF-alpha, IL-6 and NO in serum from the initiated and recovery of HAPE patients. METHODS: We studied 10 HAPE patients in a Chinese population. The patients were divided into two groups including HAPE initiate group and the recovery group. Contents of VEGF, TNF-alpha, IL-6 and NO in serum of the two groups were determined to study the process of HAPE. RESULTS: VEGF levels in the HAPE initiate one and the recovery groups were (167.9 +/- 26.5 and 53.1 +/- 17.0 pg/ ml), respectively. There was a significant decrease of VEGF content in recovery one compared to the HAPE group. The same results for TNF-alpha were gained. The levels of TNF-alpha in recovery group was much lower than that in the HAPE initiate one. They were (29.2 +/- 6.8) pg/ml and (86.2 +/- 24.1) pg/ml, respectively. The contents of IL-6 in HAPE initiate group and the recovery group were (32.3 +/- 16.5) pg/ml and (12. 5 +/- 8.0) pg/ml, respectively. But no significance existed. The level of NO in HAPE initiate group was (33.8 +/- 3.3) micromol/L, and it remarkably increased to (74.1 +/- 6.2) micromol/L in recovery one. CONCLUSION: VEGF, TNF-alpha, IL-6 and NO participated in the different aspects of the pathophysiological process and might have influence on HAPE.

Analysis of two sequence variants in peroxisome proliferator-activated receptor gamma gene in a Tibetan population at high altitude and a Han population at low altitude in China.

BACKGROUND: The Tibetan people in China have lived at high altitude for thousands of years, raising the possibility that the Tibetans are genetically adapted to high altitude. In this study we analyzed the Pro12Ala (C>G) polymorphism in exon 2 and the 161C>T polymorphism in exon 6 of peroxisome proliferator-activated receptor gamma gene (PPARγ) in a Tibetan population and a Han population. MATERIAL/METHODS: We recruited 142 Tibetan volunteers who are permanent inhabitants in Qingzang plateau (higher elevation) and 266 Han volunteers who are permanent inhabitants in the plain (lower elevation). PCR/RFLP method was applied to examine the 2 polymorphisms in the 2 populations. RESULTS: Significantly higher Pro12Ala (C>G) CC genotype frequency and 161C>T CC genotype frequency were observed in the Tibetan population compared to the Han population (p<0.001). When the samples were stratified by sex, significant differences were only observed in females. The haplotypes constructed by Pro12Ala (C>G) and 161C>T were also analyzed. The frequency of the haplotype CC (p<0.0001) was significantly higher, while the frequency of the haplotype CT (p<0.0001) and GT (p<0.01) was significantly lower in the Tibetan population than in the Han population. CONCLUSIONS: Our results suggested that PPARγ might be a candidate gene for high-altitude adaptation; the Pro12Ala (C>G) CC genotype and/or the 161C>T CC genotype are possibly advantageous factors in the female Tibetan population. Alternatively, the difference of the Pro12Ala (C>G) genotype distribution and /or the difference of the 161C>T genotype distribution in the 2 populations may be due to the racial difference.

[Protective effects of new compound codonopsis tablets against acute mountain sickness].

OBJECTIVE: To study on the protective effects of new compound codonopsis tablets against acute mountain sickness (AMS). METHODS: Forty-five male plain resident soldiers stayed at 1400 m altitude for 3 months were randomly divided into two groups, control (15 men) and treatment group (30 men). Single blind trial was used in this study. The subjects in the two groups took placebo and new compound codonopsis tablets respectively for 5 days before climbing to high mountain, and continued to take for another 10 days until the 3rd day after arriving at 5200 m altitude. On the 1st , 3rd, and 5th day after they arrived at 5200 m altitude, the score and the degree of AMS symptoms of soldiers were followed up and recorded according to State Military Standard GJB1098-91--"Principles of diagnosis and treatment of benign form of acute mountain sickness", heart rate (beats/min) and arterial oxygen saturation (%) were detenrmined. On the 6th day after they arrived at high altitude, forced vital capacity(FVC), forced expired volume in one second(FEV1.0), FEV1% (FEV1.0/FVC), FEF25%-75%, peak expiratory flow (PEF) and maximal voluntary ventilation (MVV) were detected, total frequency of hands cross movement and memory of order numbers test were measured. RESULTS: Comparison with control, AMS symptoms of treatment group reduced on the 1st, 3rd, and 5th day after arriving at 5200 m high altitude (P < 0.01). The degree of AMS symptoms of treatment group was significantly different from that of control. The proportion of slight symptoms in treatment group was high, and that of relative serious symptoms in control was high. Compared with control, FVC, FEV1.0, FEF25%-75%, PEF and MVV of treatment group increased (P < 0.05, P < 0.01), and Ttis, Ctis of treatment group increased (P < 0.05, P < 0.01), Atime decreased markedly (P < 0.05), there was no statistically significant difference in Etis and Sum between the two groups. CONCLUSION: New compound codonopsis tablets could decrease the incidence of AMS, mitigate the symptoms of AMS, and improve breathing function and fingers movement function. New compound codonopsis tablets have an obvious effect on prevention and treatment of acute mountain sickness.

[Inhibitory effect of N-acetylcysteine upon atherosclerotic processes in rabbit carotid].

OBJECTIVE: To discuss the effect of N-acetylcysteine (NAC) upon matrix metalloproteinases (MMP) in the atherosclerotic processes in rabbit carotid. METHODS: The atherosclerotic models were generated in vitro by injuring rabbit internal carotid with arterial canal balloon. These rabbits were divided into 3 groups (15 mg/kg NAC, 30 mg/kg NAC and control group) and treated for 8 weeks. HE staining and immunohistochemistry were used to observe the plaque formation and the distribution of MMPs and ox-LDL. ELISA was used to detect the level of ox-LDL. And the protein levels of MMP-2 and MMP-9 in rabbit venous blood were detected by SDS PAGE zymography. The mRNA level of MMP-2 and MMP-9 were measured by RT-PCR and electrophoresis. RESULTS: As compared with the control group, NAC (15 mg/kg) group had a reduction of neointima of arterial lumen [(1.79 +/- 0.24) vs (2.78 +/- 0.17) mm2]. A decrease of endothelial thickness [(0.16 +/- 0.01) vs (0.24 +/- 0.02) mm2] and an increase of vascular cavity transverse [(0.58 +/- 0.10) vs (0.33 +/- 0.1) mm2] (P < 0.05) were observed. At week 8, the oxLDL levels decreased by 16% in NAC (30 mg/kg) group [(30.5 +/- 1.2) vs (36.2 +/- 1.8) mmol/L] (P < 0.01). Serum levels of pro-MMP-2, MMP-2 and pro-MMP-9 decreased markedly [INT/mm2: (311 +/- 19, 208 +/- 8, 283 +/- 7 vs 619 +/- 17, 574 +/- 8, 564 +/- 10) respectively, P < 0.01] in NAC (30 mg/kg) group. The levels of mRNA expression of MMP-2 and MMP-9 were (2.4 +/- 0.4, 2.8 +/- 0.2) vs (3.4 +/- 0.3, 3.7 +/- 0.5) respectively (P < 0.05). CONCLUSION: NAC inhibits the atherosclerotic formation, suppresses the levels of ox-LDL, MMP-9 and MMP-2 and downgrades the expression of matrix metalloproteinase mRNA.

[Investigation of hyperbaric oxygen preconditioning on anoxic resistance and anti-weariness at high altitude].

AIM: To explore the influence of hyperbaric oxygen (HBO) preconditioning on anoxic resistance and anti-weariness at high altitude. METHODS: (1) SOD, MDA, NO, NOS, BLA and BUN of 20 youths living at 3 700 m altitude for half year were tested, then they were divided into group A (n=10, received HBO pretreatment twice) and group B (n=10, received HBO pretreatment 5 times) randomly. They were asked to pedal the EMG-bicycle-ergometer at the second and eighth day, and then the same items were tested. (2) 29 youth who would go to Astronomical Spot (5200 m) were randomly divided into group HBO (n=11, received HBO pretreatment once per day for 2 days at Yecheng (1400 m)) and comparison group (n=10). When they reached I Astronomical Spot, thematic biochemical index were investigated. (3) When 20 youth reached Thirty Milepost Barracks (3700 m) at the second day in their way to Immortal Gulf (5380 m) from Yecheng were randomly divided into group HBO (n=10, received HBO pretreatment once per day for 3 days) and comparison group (n=10). When they reached Immortal Gulf, the thematic biochemical index were investigated. RESULTS: (1) SOD, NO, NOS were increased and BLA, BUN, MDA were decrease in group A compared with that in group B until the eighth day, there was significant difference (P < 0.01). (2) SOD, NO, NOS were increased and BLA, BUN, MDA were decrease in group HBO compared with that in comparison that in group, there was significant difference between groups (P < 0.01, or P < 0.05). CONCLUSION: HBO could enhance the activity of anti-oxidase and the cleared ability of lactic acid, and the effect of anti-weariness could last for 8 days.

[Breakage and regrowth of flocs coagulation with polyaluminum chloride (PACl)].

The conventional jar test and the monitoring technique of floc size in line were employed to investigate the breakage and regrowth of the flocs formed by PACl. It was found that the breakage and regrowth of flocs varied with coagulation zones. The flocs formed in stabilization zone were of high strength and difficult to break, and could regrow better after broken, with the recovery factor of up to 259%. The flocs formed in charge neutralization zone were of the lowest strength and prone to break, but could reform completely after broken. The flocs formed in restabilization and sweep coagulation zones were also of high strength and difficult to break, but significantly irreversible after broken. The recovery factor of the broken flocs in sweep coagulation zone was only 18.6%. The effects of remixing on the breakage and regrowth of flocs increased with remixing intensity. In sweep coagulation zone, the settling height and mean settling velocity of the interface between flocs blanket and water were lower for the broken and partly reforming flocs than for those unbroken; Moreover, in flocculation settling and zone settling zones, the instantaneous settling velocity of the interface at the same flocs concentration was also lower for the broken flocs than for those unbroken, but in compression settling zone, the instantaneous settling velocity was the same whether the flocs were broken or not.

[Intervention of nutritional status and hypoxia endurance by a nutritional supplement in young adults living at high altitude].

AIM: To investigate the effects of a nutritional supplement on nutritional status and hypoxia endurance in young adults living at high altitude. METHODS: Forty healthy male young adults were recruited and randomly assigned to control and intervention groups. The nutrition survey was carried out using weighing method. The intervention group was given a nutritional supplement specifically designed for use at high altitude, while the control group was treated with a supplement made of stir-fried flour. After 20 days of supplementation, they marched from the altitude of 3700 m to 5100 m. The changes in HR, SaO2, serum concentrations of VA and VB2 and some minerals were measured. RESULTS: The results of nutrition survey showed that the ratio of three macronutrients was not adequate and the intakes of calcium, VA and VB2 were below Chinese RNI. The serum concentrations of calcium, magnesium and VA were below normal references. The serum VB2 concentration was at the low level o f normal reference. The nutritional supplement could increase the serum concentrations of calcium, magnesium, VA and VB2, indicating an improved nutritional status. The changes in HR and SaO2 were diminished in intervention group compared with control group. CONCLUSION: The nutritional supplement can improve nutritional status and increase the hypoxia endurance in young adults living at high altitude.

[Studies on immunoregulation of polysaccharides-la from Radix Cynanchi Bungei].

OBJECTIVE: To study the effects of PRCB1a (one component of polysaccharides from Radix Cynanchi Bungei) on transformation of T lymphocytes of rabbit in vitro and immune function in mice. METHOD: Three doses of PRCB1a (2,4,6 g x L(-1)) were respectively put in bottle with PHA and blood of rabbit. The effect of PRCB1a on immunity in vitro was studied by observing transformation of T lymphocytes; The dosage of PRCB1a (50,100,150 mg x kg(-1) x d(-1)) was given orally for seven days. The effects on immune function were investigated in mice. RESULT: Three doses of PRCB1a could significantly promote (P < 0.01) the ability of T lymphocytes proliferation; PRCB1a could improve the mouse thymus and spleen index, the celiac macrophage ability of engulfing CRBC, the delayed type hypersensitivity ability and the macrophage engulfing carbon granula ability. CONCLUSION: The results indicate PRCB1a can enhance nonspectific and specific cellular immune function.

Prevention of intimal hyperplasia; Initial results with low-dose beta-radiation applied by an external vascular polymer wrap.

OBJECTIVE: Endovascular brachytherapy, delivered by a variety of catheter-based devices, has proven clinically effective for the inhibition of neointimal hyperplasia (NIH) after coronary and peripheral balloon/stent angioplasty. No platform, however, has been developed to deliver low-dose radiation in concert with vascular surgical operations. The purpose of this study was to evaluate the vascular response following balloon injury to the rabbit carotid artery, with and without topical low-dose 45Ca, applied by an external vascular "wrap". METHODS: Twelve rabbit carotid arteries were subjected to balloon injury by embolectomy catheter. The common carotid artery was then "wrapped" circumferentially with a biostable polyurethane membrane (Nanoskin Secant Medical, Perkasie, PA), without radiation (n = 6), or with radiation (n = 6) (45Ca approximately 50 microCi). The animals were sacrificed at 4 weeks for histologic assessment of the treated vessels. RESULTS: The 45Ca wrap inhibited NIH evidenced by trends towards reduction of intimal area (0.46 +/- 0.19 control carotid vs. 0.35 +/- 0.15 (45)Ca-treated carotid arteries; P = .11), maximal intimal thickness (0.21 +/- 0.08 vs. 0.16 +/- 0.05; P = .12), average intimal thickness (0.12 +/- 0.06 vs. 0.08 +/- 0.03; P = .08), marginally significant reduction in percent area stenosis (33 +/- 15% vs. 21 +/- 9%; P = .06) and marked neointima suppression in areas immediately adjacent to 45Ca wrap remnants. Medial necrosis (P = .003), however, was observed slightly more for 45Ca-treated carotid arteries versus control arteries. CONCLUSION: Low-dose 45Ca beta-radiation labeled onto a polyurethane membrane appears to inhibit NIH in an animal model.

[Investigation of bromate, haloacetic acids and perchlorate in Beijing's drinking water].

Disinfection by-products and perchlorate in the raw water and finished water of Beijing's a drinking water plants were investigated. The results indicated that there was little bromate in the drinking water. Five haloacetic acids (HAAs) were found in the water. The concentrations of the sum of the five HAAs were ranged from 42.1 micrograms/L to 149.5 micrograms/L. In the HAAs, the chlorine-containing HAAs accounted for more than 90% of the total HAAs. In the five HAAs, the concentration order of the HAAs were trichloroacetic acid > dichloroacetic acid > bromochloroacetic acid > dibromoacetic acid > bromodichloroacetic acid. The HAAs in Beijing's drinking water were much influenced by the variation of season. They had the highest concentrations in September and lowest concentration in April, respectively. For perchlorate in Beijing's drinking water, it was greatly influenced by the groundwater. Its concentrations were between 0.1-6.8 micrograms/L in the finished drinking water. It had peak value in November and minimum value in July, respectively.