Search

Four isostructural lanthanide coordination polymers with a phenylacetate (PAA - ) ligand, [Ln(PAA) 3 (H 2 O)] n (Ln = Eu (1); Gd (2); Tb (3); Dy (4)), were synthesized under hydrothermal conditions. Complexes 1-4 display a one-dimensional (1D) wave chain structure bridged by the carboxylate of the PAA - ligand, which was generated via the in situ decarboxylation of phenylmalonic acid. Magnetic studies suggest the presence of ferromagnetic LnLn coupling in the 1D chain of 1-4. Meanwhile, 2 has a significant cryogenic magnetocaloric effect with the maximum -ΔS m of 26.73 at 3 K and 7 T, and 3 and 4 show interesting spin-glass behavior, which is rarely reported for Ln-containing complexes. Additionally, the solid-state photophysical properties of 1 and 3 display strong characteristic Eu 3+ and Tb 3+ photoluminescence emission in the visible region, indicating that Eu- and Tb-based luminescence are sensitized by the effective energy transfer from the ligand to the metal centers.

To assess racial, sexual, and regional differences in cerebral hemodynamic response to high altitude (HA, 3658 m). We performed cross-sectional comparisons on total cerebral blood flow (TCBF = sum of bilateral internal carotid and vertebral arterial blood flows = QICA + QVA), total cerebrovascular resistance (TCVR), total cerebral oxygen delivery (TCOD) and QVA/TCBF (%), among six groups of young healthy subjects: Tibetans (2-year staying) and Han (Han Chinese) at sea level, Han (2-day, 1-year and 5-year) and Tibetans at HA. Bilateral ICA and VA diameters and flow velocities were derived from duplex ultrasonography; and simultaneous measurements of arterial pressure, oxygen saturation, and hemoglobin concentration were conducted. Neither acute (2-day) nor chronic (>1 year) responses showed sex differences in Han, except that women showed lower TCOD compared with men. Tibetans and Han exhibited different chronic responses (percentage alteration relative to the sea-level counterpart value) in TCBF (-17% vs. 0%), TCVR (22% vs. 12%), TCOD (0% vs. 10%) and QVA/TCBF (0% vs. 2.4%, absolute increase), with lower resting TCOD found in SL- and HA-Tibetans. Our findings indicate racial but not sex differences in cerebral hemodynamic adaptations to HA, with Tibetans (but not Han) demonstrating an altitude-related change of CBF distribution.

Background: The purpose of the current study was to investigate the pathological characteristics of chronic kidney diseases in the Tibet plateau and the plain., Methods: 77 cases from the Tibet plateau and 154 cases from the plain of renal biopsied patients with chronic kidney diseases were compared in a randomized, and parallel controlled manner. Pathological characteristics were defined according to the standards of WHO and associated classifications., Results: The ration of sex was shown that most of patients in the plateau region were female, whereas those in the plain were male. The characteristics of pathological types were shown that the patients in the plateau region were primarily minimal change disease, but IgA nephropathy was rare; meanwhile, the proportional lupus nephritis (LN) ratio of the secondary glomerulonephritis in the plateau region was significantly lower than those in the plain region., Conclusions: The current data demonstrated that the most common kidney disease in the Tibet Plateau region is still the primary glomerulonephritis as the same as those in the plain region. However, the primary glomerular disease in the plateau region is minimal change disease, and the most common clinical manifestations are the nephrotic syndrome. The IgA nephropathy in the plain is the most frequent disease. In terms of the secondary renal diseases, Henoch-Schnolein purpura nephritis are dominated in the plateau region, whereas LN-based diseases are frequently found in the plain. There is a statistical significance existed between those two groups.

Background: To explore the predictive factors of cardiorespiratory abnormality in nonsedated patients at high altitude (HA) during upper gastrointestinal endoscopy (UGIE)., Methods: The pulse and saturated oxygen (SaO2) levels of 993 patients undergoing nonsedated UGIE in Tibet were monitored. Bivariate correlation and logistic regression were used to identify predictive risk factors for hypoxemia., Results: The basal and minimum SaO2 levels during UGIE of the Tibetan group were significantly higher than those of the non-Tibetan group. The minimum SaO2 and maximum pulse in the HA transient residents groups were significantly higher than those in the HA usual residents groups. The incidences of hypoxemia and severe hypoxemia in the Tibetan groups were significantly lower than those of the non-Tibetan groups. Bivariate correlation and logistic regression showed that race, age (≥ 40 years), residence time in HA (<10 years), and basal SaO2 (<89 %) were sufficiently effective to predict hypoxemia. High-risk hypoxemic patients whose residence time in HA was <2 years were more prone to severe hypoxemia. The combination of the four variables showed superior performance in hypoxemia prognosis (AUC-ROC, 0.941; sensitivity, 83.7 %; specificity, 92.5 %) and severe hypoxemia prognosis (AUC-ROC, 0.968; sensitivity, 90.3 %; specificity, 98.0 %)., Conclusions: Race, age, residence time in HA, and basal SaO2 of patients in HA were predictive variables for hypoxemia during UGIE. Non-Tibetan patients with age ≥ 40 years, residence time in HA <10 years, and basal SaO2 <89 % were prone to hypoxemia. Among those groups, patients whose residence time was <2 years were at higher risk for severe hypoxemia.

Aim: To study whether over-starvation aggravates intestinal mucosal injury and promotes bacterial and endotoxin translocation in a high-altitude hypoxic environment., Methods: Sprague-Dawley rats were exposed to hypobaric hypoxia at a simulated altitude of 7000 m for 72 h. Lanthanum nitrate was used as a tracer to detect intestinal injury. Epithelial apoptosis was observed with terminal deoxynucleotidyl transferase dUTP nick end labeling staining. Serum levels of diamino oxidase (DAO), malondialdehyde (MDA), glutamine (Gln), superoxide dismutase (SOD) and endotoxin were measured in intestinal mucosa. Bacterial translocation was detected in blood culture and intestinal homogenates. In addition, rats were given Gln intragastrically to observe its protective effect on intestinal injury., Results: Apoptotic epithelial cells, exfoliated villi and inflammatory cells in intestine were increased with edema in the lamina propria accompanying effusion of red blood cells. Lanthanum particles were found in the intercellular space and intracellular compartment. Bacterial translocation to mesenteric lymph nodes (MLN) and spleen was evident. The serum endotoxin, DAO and MDA levels were significantly higher while the serum SOD, DAO and Gln levels were lower in intestine (P < 0.05). The bacterial translocation number was lower in the high altitude hypoxic group than in the high altitude starvation group (0.47 ± 0.83 vs 2.38 ± 1.45, P < 0.05). The bacterial translocation was found in each organ, especially in MLN and spleen but not in peripheral blood. The bacterial and endotoxin translocations were both markedly improved in rats after treatment with Gln., Conclusion: High-altitude hypoxia and starvation cause severe intestinal mucosal injury and increase bacterial and endotoxin translocation, which can be treated with Gln.

Objective: To investigate the relationship between gastrointestinal dysfunction (GD) and multiple organ dysfunction syndrome (MODS) in acute severe mountain sickness (ASMS), including high altitude pulmonary edema (HAPE), and high altitude cerebral edema (HACE), by a retrospective study of medical records and prospective study of hospitalized patients., Methods: In retrospective study, the clinical data of 3 184 inpatients of General Hospital of Tibetan Military Command suffering from ASMS in the past 50 years (from June, 1958 to June, 2007) were collected. Statistical analysis was performed to study the relationship between GD and MODS in these patients. For the prospective study, 10 admitted patients of ASMS were included. Gastroscopic examination was performed for the ASMS patients, and gastric and duodenal mucosa was scrutinized. At the same time, 30 g of glutamine (Gln) capsule was orally ingested each day for 3 days after the first day of admission. Ten healthy volunteers were included in the control group, and received the same treatment. The levels of serum diamine oxidase (DAO), malonic dialdehyde (MDA), endotoxin and lactulose/mannitol (L/M) ratio were detected before and after treatment in two groups., Results: First, 49.8% of the patients with ASMS were complicated with GD, with 1.5% of fairy stool, and 1.0% with occult blood in stool. In 83 cases of ASMS complicated with MODS, 21.7% (18 cases) appeared GD, and the score of GD was 5.5 in the total score of all organ injury. Second, endoscopic examination showed extensive edema and localized hemorrhage in gastrointestinal mucous membrane, with dotted and patched erosion in gastric antrum and fundus. The pre-treatment DAO, MDA, and endotoxin were higher in the observation group than those in the control group (all P<0.01). After 3 days of Gln capsule treatment, DAO, MDA, and endotoxin were significantly decreased in the observation group (P<0.05 or P<0.01). The pre-treatment L/M ratio in observation group was significantly higher than that in healthy control group (150.69+/-19.91 vs. 117.91+/-17.78, P<0.01). The L/M ratio was significantly decreased after the treatment, as it decreased to 129.37+/-19.75 (P<0.05). However, no significant change in the healthy control group was observed., Conclusion: GD plays a major role in the pathogenesis of MODS in ASMS patients.

Objective: To compare the effects of liquids with different osmotic pressure and different oxygen concentration on resuscitation of hemorrhagic shock at high altitude., Methods: Hemorrhagic shock model of Sprague-Dawley (SD) rats was reproduced by Weigger method at the altitude of 3,658 meters. After 1 hour blood loss, the rats were treated either with normal saline, 75 g/L hypertonic saline solution, 60 g/L dextran 40 solution, solution of 75 g/L hypertonic saline solution with 60 g/L dextran 40, or hypertonic sodium chloride hydroxyethyl starch 40 solution, and all the above solutions were oxygenated with oxygen by high pressure. All the solutions were infused via external jugular vein (4 ml/kg) to resuscitate the rats, and the effects of different solutions on blood pressure (BP), blood gas, intraventricular pressure, water contents of lung or brain, survival time and survival rates were observed., Results: The BP, mean arterial pressure (MAP), partial pressure of oxygen in artery (PaO2), left ventricular systolic pressures (LVSP), maximum upstroke velocity (+dp/dt max) and maximum descending velocity (-dp/dt max) of intraventricular pressure, survival time and survival rate were increased (P<0.05 or P<0.01), but the survival time of the rats in groups treated with hypertonic solutions or hypertonic colloid solutions was obviously prolonged. In particular, survival time and survival rate of the rats in the groups treated with hypertonic colloid solutions were raised more significantly than those of other groups. Besides, the results showed that BP rose steadily in all the groups, PaO2 and LVSP of these groups significantly increased, but partial pressure of carbon dioxide in artery (PaCO2) showed no significant change. Infusion of 4 ml/kg of liquids did not increase water contents of lung or brain. Hyperoxic solutions had no effect on the right ventricular pressure, but the oxygenated liquids could lower the right ventricular pressure at the beginning of resuscitation, suggesting that oxygen transfer through the vein could lower the pulmonary artery pressure and improve the right ventricle function., Conclusion: Liquids with different osmotic pressure and at different oxygen concentration showed therapeutical effect on hemorrhagic shock at high altitude in rat, with hypertonic colloid solution being the best among the liquids under examination.

Objective: To study the role of white blood cell (WBC) and interleukins (ILs) in acute mountain sickness (AMS) complicated with multiple organ dysfunction syndrome (MODS)., Methods: Three thousand one hundred and eighty-four patients suffering from severe AMC in the past 50 years were surveyed with questionnaire. Correlation analysis was done to explore the relationship between differential count of WBC and elevation of ILs contents and MODS., Results: There was no difference in differential count of WBC between essential high altitude pulmonary edema (HAPE) and secondary HAPE. No difference was also found between simple HAPE and high altitude cerebral edema (HACE). However, obvious difference in WBC was found between HACE accompanied by HAPE and simple HAPE or simple HACE in the differential counts of WBC, counts of WBC and neutrophil were significantly elevated, while lymphocyte was significantly declined (all P < 0.05). The count of WBC in people suffering from AMS accompanied by MODS was higher than patients only suffering from AMS, lymphocyte was significantly decreased, the difference was obviously (both P < 0.01). The content of tumor necrosis factor-alpha (TNF-alpha), IL-1, IL-2, IL-6 and IL-8 of severe AMS patients were obviously higher than that of normal people, therefore the content of IL-4 in severe AMS patients was obviously lower than that normal people the difference were obvious (all P < 0.01)., Conclusion: People suffering from AMS also exist systemic inflammatory response syndrome (SIRS). SIRS play an important part in MODS which is a major cause of AMS, and it's a critical factor of high altitude MODS.

Objective: To study the effect of inhaled nitrogen monoxidum (NO) on endothelium-derived angiokinetic factors including NO, endothelin (ET), thromboxane B(2) (TXB(2)) and 6-keto-prostaglandin F(1a) (6-Keto-PGF(1a)) in patients with acute high altitude disease., Methods: Forty-seven patients with acute high altitude disease were selected and divided into two groups randomly: twenty-three cases as a routine medical treatment group, for which oxygen, aminophylline, dexamethasone and furosemide were used, while 24 cases as a NO treatment group, for which only inhalation of 0.001% NO gas with air balanced in plateau (altitude 3658 m), were given twice daily (AM and PM each for an hour). The level of serum NO, ET, TXB(2) and 6-Keto-PGF(1a) were measured, and the changes of clinical symptoms were scored using the Lake Louise acute high altitude disease scoring., Results: In the two groups, the level of ET [(78 +/- 8) and (69 +/- 5) ng/L], TXB(2) [(87 +/- 13) and (73 +/- 8) ng/L], ET/NO [(26.7 +/- 1.5) x 10(3) and (21.8 +/- 1.1) x 10(3)], TXB(2)/6-Keto-PGF(1a) (0.84 +/- 0.36 and 0.58 +/- 0.11, clinical symptom score 2.4 +/- 1.6 and 1.8 +/- 1.3) after treatment were decreased significantly as compared to the levels of ET [(83 +/- 8) and (84 +/- 4) ng/L], TXB(2) [(102 +/- 16) and (103 +/- 13) ng/L], ET/NO [(35.0 +/- 2.7) x 10(3) and (36.3 +/- 3.1) x 10(3)], TXB(2)/6-Keto-PGF(1a) (1.28 +/- 0.38 and 1.24 +/- 0.28), clinical symptom score (4.4 +/- 2.3 and 4.4 +/- 2.0) before treatment. After treatment, the level of NO [(2880 +/- 537) and (3167 +/- 192) microg/L] and 6-Keto-PGF(1a) [(122 +/- 46) and (128 +/- 15) ng/L] were significantly higher than the level of NO [(2372 +/- 144) and (2313 +/- 188) microg/L] and 6-Keto-PGF(1a) [(86 +/- 28) and (86 +/- 13) ng/L] before treatment., Conclusion: Inhaled NO is an effective treatment for high altitude disease in plateau, probably by modulating the angiokinetic factors.

Objective: To investigate and analyze the probability of acute mountain sickness (AMS) [including high-altitude cerebral edema (HACE) and high-altitude pulmonary edema (HAPE)] complicated by multiple organ dysfunction syndrome (MODS) and its pathogenetic mechanisms., Methods: Questionnaire survey was made to retrospectively study the hospitalization cases in the past 50 years, and the incidence of high-altitude MODS (H-MODS) were statistically analyzed to determine the main causes and pathogenic mechanism of MODS., Results: Among 3 184 cases with severe AMS, 83 cases conformed to the diagnostic criteria of diagnosis of H-MODS, and the incidence was 2.6%. The pathogenesis of acute H-MODS might be related to the activation of inflammation pathways, activation of blood clotting pathways and the damage to gastrointestinal mucosa barrier. Therefore, improving the diagnosis and the treatment effects of H-MODS is an important measure to increase cure rate of AMS and to decrease its death rate., Conclusion: AMS complicated by multiple organ damage (MOD) is the main factor that influences the therapeutic efficacy. Prompt effective remedy on the spot is a significant measure to reduce incidence of MOD.

Objective: To describe the incidence and clinical characteristics of acute severe high-altitude diseases in indigenous Tibetans., Methods: The medical records of indigenous Tibetan patients with high-altitude pulmonary edema (HAPE) and high-altitude cerebral edema (HACE), who were treated in this hospital from June of 1956 to June of 2005, were retrospectively reviewed., Results: A total of 3 184 cases of high-altitude disease were recorded in this period. Twenty four patients (0.75%, 24/3 184), 21 with HAPE and 3 with HACE, were indigenous Tibetans. Risk factors or precipitating factors were found in all the 24 cases, including getting into even higher altitude, exertion, cold, and alcohol drinking. From clinical symptoms, physical signs and laboratory examinations, it was found that 9 cases were complicated with multi-organ dysfunction., Conclusion: Indigenous Tibetans who travel between the plateau and the plain or to even higher altitude can suffer from hypoxic injury, even acute severe high-altitude disease, which may be complicated by multi-organ dysfunction.

The title novel manganese(II) coordination polymer, {(C10H10N2)[MnCl4]}n, consists of a one-dimensional infinite zigzag chain composed of polymeric [MnCl4]2- units in which each Mn2+ ion is located on a twofold rotation axis and is coordinated to two terminal Cl atoms and four bridging chloro ligands. Adjacent Mn2+ ions are linked by double Cl bridges arranged about a centre of inversion, thus forming anionic chains of distorted edge-sharing octahedra. Rows of approximately parallel 4,4'-bipyridinium cations run side-by-side with the MnCl4 chains. A two-dimensional layer structure is constructed via hydrogen bonds and by additional pi-pi stacking interactions.

Aim: To assay ET and NO in venous blood of native Tibetan and to investigate the effects of hypoxia on ET and NO levels in cultured umbilical venous endothelial cells of native Tibetan., Methods: ET and NO in venous blood of native Tibetan, immigrant Han and lowland Han were assayed. Umbilical venous endothelial cells (UVECs) from native Tibetan and immigrant Han newborns were cultured and divided into 4 groups: (1) Native Tibetan control group (TC), (2) Native Tibetan hypoxic group (TH), (3) Immigrant Han control group (HC), (4) Immigrant Han hypoxic group (HH). Supernatant was collected and ET and NO were detected., Results: Venous blood NO was significantly higher in native Tibetan than in immigrant Han, while ET lower in native Tibetan than in immigrant Han. ET excretion from UVECs was elevated while NO decreased in both Tibetan and Han groups after exposed to hypoxia. On time-points 12 h and 24 h, ET was significantly lower in TH than in HH, while concentration of NO showed no difference in TH and HH., Conclusion: ET released by UVECs was higher in Han than in Tibetan after 12 h and 24 h hypoxic exposure, which may be in favor of lower vascular resistance and better fetal blood supply in Tibetan, and thus plays a role in the mechanisms of less intrauterine growth restriction (IUGR) throughout pregnancy and heavier birth weight of Tibetan newborns.

Objective: To study chronic high altitude disease (CHAD) with concurrent acute high altitude disease (AHAD) in regions of high altitude., Methods: 18,090 inpatients from Feb. 1956 to Dec. 1995 conforming to a screening standard were observed in a hospital located at altitude 3658 m. 1,028 inpatients suffering from CHAD when hospitalized were collected as a study group. 17,020 inpatients suffering from non-HAD when first hospitalized served as a control group. The morbidity rate of AHAD in these two groups in a follow-up period of 1 - 20 years was analyzed., Results: (1) AHAD morbidity rate was increasing with prolongation of observation time in the control group, but it was not so in the study group. Annual and accumulative morbidity of AHAD in the study group was obviously higher than that in the control group (P < 0.005, OR = 5.03, RR = 4.33). (2) The morbidity rates of three types of AHAD aside from high altitude pulmonary edema (HAPE) of high altitude hypertension (HAH) group and high altitude cerebral edema (HACE) of high altitude heart disease (HAHD) group was obviously higher in the study group than in the control (P < 0.05 - 0.005). AHAD morbidity rate in HAHD group and Monge's disease was 23.5% and 22.0% (OR = 7.33 - 6.71, RR = 5.86 - 5.47). (3) AHAD morbidity rate in HAHD group and Monge's disease group was obviously higher than that in the control, constituting mainly a high morbidity of mild acute high altitude disease., Conclusion: The risk of AHAD increases about 5-fold in CHAD patients than in the multitude of high altitude acclimatization, being most evident in HAHD and Monge's disease.