Association between physiological responses after exercise at low altitude and acute mountain sickness upon ascent is sex-dependent.

BACKGROUND: Acute mountain sickness (AMS) is the mildest form of acute altitude illnesses, and consists of non-specific symptoms when unacclimatized persons ascend to elevation of ≥2500 m. Risk factors of AMS include: the altitude, individual susceptibility, ascending rate and degree of pre-acclimatization. In the current study, we examined whether physiological response at low altitude could predict the development of AMS. METHODS: A total of 111 healthy adult healthy volunteers participated in this trial; and 99 (67 men and 32 women) completed the entire study protocol. Subjects were asked to complete a 9-min exercise program using a mechanically braked bicycle ergometer at low altitude (500 m). Heart rate, blood pressure (BP) and pulse oxygen saturation (SpO2) were recorded prior to and during the last minute of exercise. The ascent from 500 m to 4100 m was completed in 2 days. AMS was defined as ≥3 points in a 4-item Lake Louise Score, with at least one point from headache wat 6-8 h after the ascent. RESULTS: Among the 99 assessable subjects, 47 (23 men and 24 women) developed AMS at 4100 m. In comparison to the subjects without AMS, those who developed AMS had lower proportion of men (48.9% vs. 84.6%, P < 0.001), height (168.4 ± 5.9 vs. 171.3 ± 6.1 cm, P = 0.019), weight (62.0 ± 10.0 vs. 66.7 ± 8.6 kg, P = 0.014) and proportion of smokers (23.4% vs. 51.9%, P = 0.004). Multivariate regression analysis revealed the following independent risks for AMS: female sex (odds ratio (OR) =6.32, P < 0.001), SpO2 change upon exercise at low altitude (OR = 0.63, P = 0.002) and systolic BP change after the ascent (OR = 0.96, P = 0.029). Women had larger reduction in SpO2 after the ascent, higher AMS percentage and absolute AMS score. Larger reduction of SpO2 after exercise was associated with both AMS incidence (P = 0.001) and AMS score (P < 0.001) in men but not in women. CONCLUSIONS: Larger SpO2 reduction after exercise at low altitude was an independent risk for AMS upon ascent. Such an association was more robust in men than in women. TRIAL REGISTRATION: Chinese Clinical Trial Registration, ChiCTR1900025728 . Registered 6 September 2019.

EPAS1 and VEGFA gene variants are related to the symptoms of acute mountain sickness in Chinese Han population: a cross-sectional study.

BACKGROUND: More people ascend to high altitude (HA) for various activities, and some individuals are susceptible to HA illness after rapidly ascending from plains. Acute mountain sickness (AMS) is a general complaint that affects activities of daily living at HA. Although genomic association analyses suggest that single nucleotide polymorphisms (SNPs) are involved in the genesis of AMS, no major gene variants associated with AMS-related symptoms have been identified. METHODS: In this cross-sectional study, 604 young, healthy Chinese Han men were recruited in June and July of 2012 in Chengdu, and rapidly taken to above 3700 m by plane. Basic demographic parameters were collected at sea level, and heart rate, pulse oxygen saturation (SpO2), systolic and diastolic blood pressure and AMS-related symptoms were determined within 18-24 h after arriving in Lhasa. AMS patients were identified according to the latest Lake Louise scoring system (LLSS). Potential associations between variant genotypes and AMS/AMS-related symptoms were identified by logistic regression after adjusting for potential confounders (age, body mass index and smoking status). RESULTS: In total, 320 subjects (53.0%) were diagnosed with AMS, with no cases of high-altitude pulmonary edema or high-altitude cerebral edema. SpO2 was significantly lower in the AMS group than that in the non-AMS group (P = 0.003). Four SNPs in hypoxia-inducible factor-related genes were found to be associated with AMS before multiple hypothesis testing correction. The rs6756667 (EPAS1) was associated with mild gastrointestinal symptoms (P = 0.013), while rs3025039 (VEGFA) was related to mild headache (P = 0.0007). The combination of rs6756667 GG and rs3025039 CT/TT further increased the risk of developing AMS (OR = 2.70, P < 0.001). CONCLUSIONS: Under the latest LLSS, we find that EPAS1 and VEGFA gene variants are related to AMS susceptibility through different AMS-related symptoms in the Chinese Han population; this tool might be useful for screening susceptible populations and predicting clinical symptoms leading to AMS before an individual reaches HA. TRIAL REGISTRATION: Chinese Clinical Trial Registration, ChiCTR-RCS-12002232 . Registered 31 May 2012.

catena-Poly[[[diaqua-copper(II)]-bis-[µ-1,5-bis-(1H-imidazol-1-yl)pentane-κ(2) N (3):N (3')]] naphthalene-1,5-disulfonate].

In the title complex, {[Cu(C11H16N4)2(H2O)2](C10H6O6S2)} n , the Cu(II) atom, lying on an inversion center, is six-coordinated by two water mol-ecules and four N atoms from four 1,5-bis-(1H-imidazol-1-yl)pentane (biim-5) ligands in a distorted octa-hedral geometry. Adjacent Cu(II) atoms are linked by two biim-5 ligands, forming a chain along [111]. Two atoms of the pentane group are disordered over two sets of sites, with an occupancy ratio of 0.554 (18):0.446 (18). Inter-molecular O-H⋯O hydrogen bonds link the chains and the centrosymmetric naphthalene-1,5-disulfonate anions into a layer structure parallel to (0-11).

Series of 2D and 3D coordination polymers based on 1,2,3,4-benzenetetracarboxylate and N-donor ligands: synthesis, topological structures, and photoluminescent properties.

Nine new coordination polymers, namely, [Mn(2)(L)(H(2)O)(4)].H(2)O (1), [Cd(L)(0.5)(H(2)O)] (2), [Zn(5)(L)(2)(mu(3)-O)(2)(H(2)O)(4)].2H(2)O (3), [Zn(4)(L)(2)(mu(3)-O)(2)][Zn(H(2)O)(5)].2H(2)O (4), [Zn(2)(L)(biim-4)(0.5)(H(2)O)(3)].H(2)O (5), [Cd(2)(L)(bpy)(H(2)O)].2H(2)O.0.5(CH(3)CH(2)OH) (6), [Cu(2)(H(2)L)(2)(bpy)(2)] (7), [Cu(2)(L)(bpy)(H(2)O)] (8), and [Cu(2)(L)(bpy)(1.5)(H(2)O)(2.5)] (9), where H(4)L = 1,2,3,4-benzenetetracarboxylic acid, biim-4 = 1,1'-(1,4-butanediyl)bis(imidazole), and bpy = 4,4'-bipyridine, have been synthesized under hydrothermal conditions. Compound 1 displays a rare trinodal (3,4,7)-connected (4(2).6)(4(5).6)(4(7).6(8).8(6)) topology. 2 possesses an alpha-Po net. 3 is a novel 3D framework based on pentanuclear Zn(II) clusters. By adjustment of the pH values of the reaction mixture of 3 with a Na(2)CO(3) solution, a structurally different compound, 4, was obtained, which exhibits a 3D porous framework with the [Zn(H(2)O)(6)](2+) cations located in the channels. 5 is an unusual example of a trinodal (3,5)-connected network with a Schlafli symbol of (4(2).6)(6(2).8)(4(2).6(2).8(5).10), whereas 6, containing tetranuclear Cd(II) clusters, shows a rare (4,6)-connected (4(4).6(2))(2)(4(4).6(10).8) topology. 7 exhibits a unique polythreading network, while 8 displays a scarce trinodal (3,4,5)-connected self-penetrating network. In comparison with 8, the chiral compound 9 possesses an unprecedented tetranodal (2,4)-connected (7)(7(5).11)(6(2).7(3).8)(2)(6.7(4).10)(2) topology. The effects of the carboxylate ligands, the pH values, the reaction temperatures, the central metals, and the neutral ligands were elucidated. The IR spectra, thermogravimetric analysis, and luminescent properties for the compounds were also investigated.

Syntheses, structures and luminescent properties of zinc(II) and cadmium(II) coordination complexes based on new bis(imidazolyl)ether and different carboxylate ligands.

A series of mixed-ligand coordination complexes, namely [Zn(CA)(2)(BIE)] (1), [Zn(OX)(BIE)].H(2)O (2), [Zn(2)(m-BDC)(2)(BIE)(2)] (3), [Cd(m-BDC)(BIE)] (4), [Cd(5-OH-m-BDC)(BIE)] (5), [Zn(5-OH-m-BDC)(BIE)] (6), [Zn(2)(p-BDC)(2)(BIE)(2)].2.5H(2)O (7), [Cd(3)(p-BDC)(3)(BIE)] (8), [Cd(3)(BTC)(2)(BIE)(2)].0.5H(2)O (9) and [Zn(BTCA)(0.5)(BIE)] (10), where CA = cinnamate anion, OX = oxalate anion, m-BDC = 1,3-benzenedicarboxylate anion, 5-OH-m-BDC = 5-OH-1,3-benzenedicarboxylate anion, p-BDC = 1,4-benzenedicarboxylate anion, BTC = 1,3,5-benzenetricarboxylate anion, BTCA = 1,2,3,4-butanetetracarboxylate anion, and BIE = 2,2'-bis(1H-imidazolyl)ether, were synthesized under hydrothermal conditions. In 1, a pair of BIE ligands bridge adjacent Zn(II) atoms to give a centrosymmetric dimer. In 2 and 3, BIE ligands connect Zn(II)-carboxylate chains to form hexagonal honeycomb 6(3)-hcb and square 4(4)-sql layers, respectively. In 4 and 5, m-BDC and 5-OH-m-BDC bridge Cd(II) atoms to give dimeric units, respectively, which are further linked by BIE ligands to form sql nets. In 6, the BIE ligands extend the Zn(II)-carboxylate chains into 2D sinusoidal-like sql nets. The undulated sql nets polycatenate each other in the parallel manner with DOC (degree of catenation) = 2, yielding a rare 2D --> 3D parallel polycatenation net. In 7, the BIE and p-BDC ligands link the Zn(ii) atoms to give a rare 3-fold interpenetrated 3-connected 10(3)-ths net. 8 contains unusual edge-sharing polyhedral rods formed by [Cd(3)(CO(2))(6)] clusters. Each rod is connected by the benzene rings of p-BDC in four directions into a simple alpha-Po topology. In 9, two kinds of different 2D Cd-BTC layers are alternately linked to each other by sharing Cd(ii) centers to form a 3D framework, which is further linked by two kinds of BIE ligand to produce a complicated 3D polymeric structure. 10 possesses a unique (3,4)-connected 3D framework with (8(3))(2)(8(5).10) topology. The structural differences described indicate the importance of carboxylate ligands and metals in the framework formation of coordination complexes. The infrared spectra, thermogravimetric and luminescent properties were also investigated in detail for the compounds.

Tin-oxo clusters based on aryl arsonate anions.

Reactions of Ph(3)SnOH or Ph3SnCl with aryl arsonic acids RAsO3H2, where R=C6H5 (1), 2-NH2C6H4 (2), 4-NH2C6H4 (3), 2-NO2C6H4 (4), 3-NO2C6H4 (5), 4-NO2C6H4 (6), 3-NO2-4-OHC6H3 (7), 2-ClC6H4 (8) and 2,4-Cl2C6H3 (9), gave 18 Sn-O cluster compounds. These compounds can be classified into four types: type A: [{(PhSn)3(RAsO3)3(mu3-O)(OH)(R'O)2}2Sn] (R=C6H5, 2-NH2C6H4, 4-NH2C6H4, 2-NO2C6H4, 3-NO2C6H4, 2-ClC6H4, 2,4-Cl2C6H3, and 3-NO2-4-OHC6H3; R'=Me or Et); type B: [{(PhSn)3(RAsO3)(2)(RAsO3H)(mu3-O)(R'O)2}2] (R=4-NO2C6H4, R'=Me); type C: [{(PhSn)3(RAsO3)3(mu3-O)(R'O)3}2Sn] (R=2,4-Cl2C6H3, R'=Me); type D: [{Sn3Cl3(mu3-O)(R'O)3}(2)(RAsO3)4] (R=2-NO2C6H4 and 4-NO2-C6H4; R'=Me or Et). Structures of types A and B contain [Sn3(mu3-O)(mu2-OR')2] building blocks, while in types C and D the stannoxane cores are built from two [Sn3(mu3-O)(mu2-OR')3] building blocks. The reactions proceeded with partial or complete dearylation of the triphenyltin precursor. These various structural forms are realized by subtle changes in the nature of the organotin precursors and aryl arsonic acids. The syntheses, structures, and structural interrelationship of these organostannoxanes are discussed.

(5,6:19,20-Dibenzo-1,4,11,14-tetra-oxa-8,17-diaza-cyclo-eicosane-κN,O,O,N)dinitrato-κO,O'-cadmium(II).

In the title compound, [Cd(NO(3))(2)(C(22)H(30)N(2)O(4))], the Cd(II) atom is eight-coordinated by two amine N atoms and two O atoms from the 5,6:19,20-dibenzo-1,4,11,14-tetra-oxa-8,17-diaza-cyclo-eicosane ligand and four O atoms from two nitrate groups. The coordination geometry about Cd is antiprismatic. One nitro O atom is disordered equally over two positions.

(Benzene-1,3-dicarboxyl-ato-κO,O)(1,12,15,26-tetra-aza-5,8,19,22-tetra-oxa-3,4:9,10:17,18:23,24-tetra-benzocyclo-octa-cosane-κN,N,N,N)cadmium(II) benzene-1,3-dicarboxylic acid solvate.

In the title compound, [Cd(C(8)H(4)O(4))(C(36)H(44)N(4)O(4))]·C(8)H(6)O(4), the Cd(II) atom is six-coordinated by four N atoms from the macrocyclic ligand and two O atoms from a benzene-1,3-dicarboxyl-ate ligand. The complex mol-ecules are linked by N-H⋯O hydrogen bonds, forming a one-dimensional chain structure along the b axis. The chains are further connected through N-H⋯O and O-H⋯O hydrogen bonds between the complex mol-ecule and an uncoordinated benzene-1,3-dicarboxylic acid mol-ecule, resulting in a two-dimensional supra-molecular network.

catena-Poly[[[bis-(4-amino-benzoato-κO)copper(II)]-µ-1,1'-(pentane-1,5-di-yl)diimidazole] trihydrate].

In the title compound, {[Cu(C(7)H(6)NO(2))(2)(C(11)H(16)N(4))]·3H(2)O}(n), each Cu(II) atom is coordinated by two O atoms from two 4-amino-benzoate anions, and two N atoms from two different 1,1'-(pentane-1,5-di-yl)diimidazole (biim-5) ligands, to furnish a distorted square-planar geometry. The biim-5 ligand coordinates to two copper(II) cations, acting as a bridging ligand; as a result the copper(II) cations are connected to form an infinite chain structure. The polymeric chains are linked through a variety of hydrogen bonds to form a three-dimensional structure.

1,1'-(4-Oxoheptane-1,7-di-yl)bis-(2-methyl-1H-benzimidazole) penta-hydrate.

The title compound, C(23)H(26)N(4)O·5H(2)O, has noncrystallographic twofold rotation symmetry in the solid state. It crystallizes with five solvent water mol-ecules in the asymmetric unit. Four of these water mol-ecules are connected with each other via hydrogen-bonding inter-actions to form two types of centrosymmetric hexa-meric (H(2)O)(6) rings. Via edge sharing of the hexa-mers, the water clusters thus build infinite chains that stretch parallel to the a axis. The fifth water mol-ecule provides an additional connection between the two hexa-meric (H(2)O)(6) units via hydrogen bonds to both rings. The water mol-ecules in the channels along the a axis are also bonded via O-H⋯N hydrogen bonds to the organic units, and face-to-face π-π inter-actions [with centroid-to-centroid distances of 3.656 (1) Šand average face-to-face distances of 3.431 (5) Å] between the aromatic rings of adjacent mol-ecules complete the inter-molecular inter-actions in this structure.