Analyses of the electronic structures of FeFe-cofactors compared with those of FeMo- and FeV-cofactors and their P-clusters

The electronic structures of FeFe-cofactors (FeFe-cos) in resting and turnover states, together with their PN clusters from iron-only nitrogenases, have been calculated using the bond valence method, and their crystallographic data were reported recently and deposited in the Protein Data Bank (PDB codes: 8BOQ and 8OIE). The calculated results have also been compared with those of their homologous Mo- and V-nitrogenases. For FeFe-cos in the resting state, Fe1/2/4/5/6/7/8 atoms are prone to Fe3+, while the Fe3 atom shows different degrees of mixed valences. The results support that the Fe8 atom at the terminal positions of FeFe-cos possesses the same oxidation states as the Mo3+/V3+ atoms of FeMo-/FeV-cos. In the turnover state, the overall oxidation state of FeFe-co is slightly reduced than those in the resting species, and its electronic configuration is rearranged after the substitution of S2B with OH, compatible with those found in CO-bound FeV-co. Moreover, the calculations give the formal oxidation states of 6Fe2+-2Fe3+ for the electronic structures of PN clusters in Fe-nitrogenases. By the comparison of Mo-, V- and Fe-nitrogenases, the overall oxidation levels of 7Fe atoms (Fe1-Fe7) for both FeFe- and FeMo-cos in resting states are found to be higher than that of FeV-co. For the PN clusters in MoFe-, VFe- and FeFe-proteins, they all exhibit a strong reductive character.

Asymmetric dinuclear, hexanuclear and octanuclear oxovanadium citrates with triazolates: novel mixed-ligands and mixed-valence complexes

The triazolate-assisted asymmetric dinuclear oxovanadium(IV) citrate [V2O2(cit)(Hdatrz)3]·5H2O (1, H4cit = citric acid, Hdatrz = 1H-1,2,4-triazole-3,5-diamine) and its additive salt [V2O2(cit)(Hdatrz)3][V2O2(cit)2]½·2H2datrz·9.5H2O (2) and the polymerized hexanuclear product [V6O6(μ3-O)2(cit)2(Hdatrz)4]·4H2O (3) have been isolated at different temperatures, respectively. Adduct 2 shows strong evidence for the conversion of a symmetric dinuclear oxovanadium(IV) citrate to a mixed-ligand asymmetric oxovanadium(IV) citrate. Moreover, a fully oxidized trinuclear vanadium(V) species [V3O6(μ2-OH)(μ3-O)(Hdatrz)2]·4.5H2O (4) has also been isolated as a quasi-intermediate product of 3 without the coordination of citrate. Intriguingly, an octanuclear mixed-valence oxovanadium(V/IV) citrate K2{[VIV/V2O2(cit)(Hdatrz)(datrz)]2[VIV2O2(cit)(Hdatrz)(datrz)]2}·27.5H2O (5) has been obtained with different vanadium units, where dinuclear mixed-ligands and mixed-valence oxovanadium(IV/V) citrates [VIV/V2O2(cit)(Hdatrz)(datrz)] (5a) and [VIV2O2(cit)(Hdatrz)(datrz)] (5b) have been trapped. Citrate adopts a μ2-η1:η1:η1:η2 coordination mode in 1, 2 and 5, while a μ3-η1:η1:η1:η2 fashion has been observed in 3. Unlike 1-4, complex 5 contains both protonated and deprotonated triazolates simultaneously, where four triazolates further coordinate in a μ3-η1:η1:η1 manner to construct an octanuclear unit. These different structural features in 1-5 are dominated by flexible multidentate citrates and protonated/deprotonated triazolates, showing their synergistic effects. Furthermore, 1 exhibits a rectangular channel, showing preferential adsorption of O2 and CO2 over gases N2, H2, and CH4.

Protonated and deprotonated vanadyl imidazole tartrates for the mimics of the vanadium coordination in the FeV-cofactor of V-nitrogenase

Chiral imidazole-based oxidovanadium tartrates (H2im)2[Δ,Λ-VIV2O2(R,R-H2tart)(R,R-tart)(Him)2]·Him (1, H4tart = tartaric acid, Him = imidazole) and [Λ,Λ-VIV2O2(R,R-tart)(Him)6]·4H2O (2) and their corresponding enantiomers (H2im)2[Λ,Δ-VIV2O2(S,S-H2tart)(S,S-tart)(Him)2]·Him (3) and [Δ,Δ-VIV2O2(S,S-tart)(Him)6]·4H2O (4) were obtained in alkaline solutions. Interestingly, the tartrates chelate with vanadium bidentately through α-alkoxy/α-hydroxy and α-carboxy groups and imidazole coordinates monodentately through nitrogen atom. It is worth noting that complexes 1 and 3 contain both protonated α-hydroxy and deprotonated α-alkoxy groups simultaneously, which have short V-Oα-alkoxy distances [1.976(4)av Å in 1-4] and long V-Oα-hydroxy distances [2.237(3)av Å in 1 and 2.230(2)av Å in 3]. There is an interesting strong intramolecular hydrogen bond [O(11)⋯O(1) 2.731(5) Å] between the two parts in 1 and 3. The protonated V-O distances are closer to the average bond distance in reported FeV-cofactors (FeV-cos, V-Oα-alkoxy 2.156av Å) in VFe proteins, which corresponds to the feasible protonation of coordinated α-hydroxy in R-homocitrate in V-nitrogenase, showing the homocitrate in the mechanistic model for nitrogen reduction as a secondary proton donor. Furthermore, vibrational circular dichroism (VCD) and IR spectra of 1-4 pointed out the disparity between the characteristic vibrations of the C-O and C-OH groups clearly. EPR experiment and theoretical calculations support +4 oxidation states for vanadium in 1-4. Solution 13C {1H} NMR spectra and CV analyses exhibited the solution properties for 1 and 2, respectively, which indicates that there should be a rapid exchange equilibrium between the protonated and deprotonated species in solutions.

Octa- and Tetradecanuclear Mixed-Valent Vanadium(III/IV) Malates with Triazoles: Gas Adsorptions, Chiral Interface Recognition, and In Situ Decarboxylation

Spontaneous resolution has been found for a pair of cage-like octanuclear mixed-valent vanadium(III/IV) malate enantiomers [Δ-V^III₄V^IV₄O₅(R-mal)₆(Hdatrz)₆]·44.5H₂O (Δ_R-1) and [Λ-V^III₄V^IV₄O₅(S-mal)₆(Hdatrz)₆]·38.5H₂O (Λ_S-1, H₃mal = malic acid; Hdatrz = 3,5-diamino-1,2,4-triazole). Their racemic reduced product K₇[V^III₅V^IV₃O₅(R,S-mal)₆(trz)₆]·17H₂O (2) and tetradecanuclear species K₁₁[V^III₃V^IV₁₁O₁₁(R,S-mal)₁₂(atrz)₆]·45.5H₂O (3) (Htrz = 1,2,3-triazole, Hatrz = 3-amino-1,2,4-triazole) have also been obtained. In situ decarboxylation happens for 3-amino-1,2,4-triazole-5-carboxylic acid (H₂atrzc) to yield 3-amino-1,2,4-triazole under hydrothermal conditions. Both 1 and 2 show an interesting bicapped-triangular-prismatic {V₈O₅(mal)₆} building block, which further decorates symmetrically with three [V^IV₂O₂(R,S-mal)₂]^2- units to construct a pinwheel-like {V₁₄}-cluster, 3. Bond valence calculation sum (BVS) analyses manifest that the oxidation states of bicapped V atoms are +3 in 1-3, while the other V atoms in the {V₆O₅} core are ambiguous between +3 and +4 states with strong electron delocalization. Intriguingly, the triple helical chains in 1 associate in parallel to generate an amine-functionalized chiral polyoxovanadate (POV)-based supramolecular open-framework. The diameter of the interior channel is 13.6 Å, showing preferential adsorption of CO₂ over gases N₂, H₂, and CH₄. Importantly, homochiral framework Δ_R-1 is capable of performing chiral interface recognition for R-1,3-butanediol (R-BDO) through host-guest interactions, as confirmed by the structural analysis of the host-guest complex Δ_R-1·3(R-BDO). There are six R-BDO molecules in the channel of Δ_R-1.

Crown ether-like discrete clusters for sodium binding and gas adsorption

Hexanuclear polyoxomolybdenum-based discrete supermolecules Na_x[Mo^V₆O₆(μ₂-O)₉(Htrz)_6-x(trz)_x]·nH₂O (x = 0, n = 15, 1; x = 1, n = 12, 2; x = 2, n = 10, 3; x = 2, n = 49, 4; Htrz = 1H-1,2,3-triazole) have been prepared and fully characterized with different amounts of sodium cations inside and outside the intrinsic holes. Structural analyses demonstrate that they all exist a triangular channel constructed by six molybdenum-oxygen groups with inner diameters of 2.86 (1), 2.48 (2), and 3.04 (3/4) Å, respectively. Zero, one, or two univalent enthetic guest Na⁺ have been hosted around the structural centers, which reflect the expansion and contraction effects at microscopic level. Water-soluble species can serve as crown ether-like metallacycles before and after the sodium binding. Diverse nanoscale pores are further formed through intermolecular accumulations with hydrogen bonding. Gas adsorption studies indicate that 2-4 can selectively adsorb CO₂ and O₂ but have little or even no affinities toward H₂, N₂, and CH₄. Theoretical calculations corroborate the roles of Na⁺ and auxiliary ligand with different states in bond distances, molecular orbitals, electrostatic potentials, and lattice energies in these discrete clusters. The binding orders of sodium cations in 2-4 are similar with the classical crown ethers, where 2 is the strongest one with 2.226(4)_av Å for sodium cation bonded to six O atoms.

[Independent and combined effects of pre-pregnancy BMI and gestational diabetes on early adiposity rebound timing in children]

Objective: To examine the independent and combined effects of pre-pregnancy BMI and gestational diabetes (GDM) on early adiposity rebound (AR) timing in children. Methods: Based on the "Ma'anshan Birth Cohort Study", 2 896 eligible maternal and infant pairs were recruited. In the cohort, we collected pre-pregnancy height, weight, 24 to 28 weeks GDM diagnosis, follow-up at 42 days, three months, six months, nine months of age, and every six months after one year of age, and continuously followed up to 6 years old, and obtained the child's length/height, weight, and other data. The intensity of the association between pre-pregnancy BMI, GDM, and early AR timing was analyzed by the multivariate logistic regression model. Multiplication and additive models were used to analyze how pre-pregnancy BMI and GDM influenced early AR timing in children. Results: The prevalence of underweight, average weight, overweight, and obesity before pregnancy were 23.2% (672), 66.4% (1 923), 8.7% (251), and 1.7% (50). The prevalence of GDM was 12.4%. We found that 39.3% of children had AR, and the average age at AR was (4.38±1.08). The results of multifactorial logistic regression analysis showed that pre-pregnancy overweight (OR=1.67,95%CI:1.27-2.19), pre-pregnancy obesity (OR=3.05,95%CI:1.66-5.56), and maternal GDM (OR=1.40,95%CI:1.11-1.76) were risk factors for early AR timing in children. In contrast, pre-pregnancy underweight (OR=0.60,95%CI:0.49-0.73) was a protective factor for early AR timing in children. Compared with the different effects of pre-pregnancy overweight/obesity and maternal GDM alone, the combined effect caused a higher risk of early AR timing in children, with OR values (95%CI) were 2.03 (1.20-3.44), 3.43 (1.06-11.12), respectively. The multiplication and additive models showed no interaction between pre-pregnancy BMI and GDM-influenced early AR timing in children. Conclusion: Higher pre-pregnancy BMI and maternal GDM are the independent risk factors for the early AR timing in children, and the co-occurrence of the two is higher risks, but there was no statistical interaction.

[Clinical efficacy evaluation of minimally invasive cardiac surgery coronary artery bypass grafting in patients with multivessel coronary artery disease]

Objective: To investigate the clinical efficacy of minimally invasive cardiac surgery coronary artery bypass grafting (MICS CABG) in the treatment of patients with multivessel coronary artery disease. Methods: A total of 147 patients with multi-vessel coronary artery disease and coronary heart disease who underwent surgical treatment in Henan Provincial People's Hospital from March 2016 to March 2019 were retrospectively selected. Of which, 69 patients were treated by MICS CABG (minimally invasive group) and 78 patients were treated using the traditional thoracotomy (traditional group). The perioperative indexes, serum myocardial enzyme indexes and renal function indexes of patients before and after operation were compared between the two groups; Two groups of patients were followed up for 2 years; the incidence of adverse cardiovascular events (MACE) was recorded, and survival analysis was performed. Results: The age of the patients in the minimally invasive group and the traditional group were (66.9±5.8) and (68.2±7.0) years old, respectively, and the proportions of males were 60.9% (42 cases) and 51.3% (40 cases) (all P>0.05). All patients in the two groups successfully completed the operation, and no patients in the minimally invasive group were converted to thoracotomy. Before surgery, there was no significant difference in serum cTnI, CK-MB, BUN, Scr, and creatinine clearance between the minimally invasive group and the traditional group (all P>0.05). After re-examination 48 hours after operation, the serum cTnI in the minimally invasive group was (3.109±0.664) μg/L, and the CK-MB was (18.03±3.27) U/L, which were lower than those in the traditional group (3.438±0.715) μg/L, (20.63±4.28) U/L; the difference was statistically significant (all P<0.05). During the 2-year follow-up, there was no statiscally significant difference in the incidence of recurrent myocardial infarction, postoperative atrial fibrillation, postoperative stroke, arrhythmia, heart failure, thrombosis, cardiac death, and MACE events between the minimally invasive group and the traditional group. Statistical significance (all P>0.05). The survival curve analysis showed that the cumulative rates of MACE events in the minimally invasive and traditional groups were 17.39% and 26.92%, respectively (P=0.171). Conclusions: The effect of MICS CABG in the treatment of patients with multivessel coronary artery disease and coronary heart disease is not much different from that of traditional open thoracotomy, but the former is less traumatic, quicker after surgery, and has clinical significance for the recovery of patients' myocardial function.

Successive constructions of regular tetra-, hexa- and octanuclear microporous polyoxovanadates(III) for gas adsorption

Pyrazole-assisted tetranuclear microporous polyoxovanadates(III) (POVs) (NH₄)₂K₂[V₄(μ₂-OH)₄(ox)₄(pz)₄]·9H₂O (1, ox = oxalate and pz = pyrazole) and (NH₄)₂Na₂[V₄(μ₂-OH)₄(ox)₄(4-mpz)₄]·7H₂O (2, 4-mpz = 4-methylpyrazole) have been constructed in reduced media, along with their triazole neutral hexa- and octanuclear products K₂[V₆(μ₂-OH)₆(ox)₆(Hdatrz)₆]Cl₂·29.5H₂O (3) and [V₈(μ₂-OH)₈(SO₃)₈(Hdatrz)₈]·38H₂O (4, Hdatrz = 1H-1,2,4-triazole-3,5-diamine) successively. Both polyanionic structures of 1 and 2 share similar inorganic building blocks that consist of regular {V₄(μ₂-OH)₄} skeletons with an inner diameter of 2.8 Å, while a paddle wheel-shaped cluster 3 contains a {V₆(μ₂-OH)₆} skeleton with two chlorides encapsulated around the center of the ring, occupying a hole of 3.7 Å. An interesting isolated intrinsic polyoxometalate-based metal-organic framework (POMOF) 4 exists as an octanuclear petaloid-like skeleton {V₈(μ₂-OH)₈(SO₃)₈} with an inner diameter of 5.2 Å. Bond valence sum calculations manifest that all V ions have severely reduced +3 oxidation states in 1-4, which are supported by charge balance, structural and magnetic data. Moreover, gas adsorptions indicate that 1, 2 and 4 can adsorb CO₂ and O₂ more favorably than N₂, CH₄ and H₂ gases. Compared with 1 and 2, due to the functionalization of microchannels with Lewis base amino and hydroxy groups and uncoordinated azolate N-donors inside POMOF 4, it should have notable affinities toward CO₂ adsorption.

[Effects of menopause on depressive and anxiety symptoms in community women in Beijing]

Objective: To determine the effects of menopausal stage, age and other associated risk factors on symptoms of anxiety and depression among women in a community in Beijing. Methods: This study was a community-based prospective cohort. Participants who had transitioned through natural menopause, completed two or more depressive and anxiety symptoms evaluations, aged 35 to 64 years, and did not use hormone therapy were selected from the Peking Union Medical College Hospital aging longitudinal cohort of women in midlife to this analysis. The primary outcome variables were depressive and anxiety symptoms, assessed by hospital anxiety and depression scale (HADS). The generalized estimation equation was used in the statistical analysis. Results: Followed up from 2006 to 2014, 430 women and 2 533 HADS assessments were retained in the cohort. Depressive symptoms were more common than anxiety symptoms during all menopausal stages. The incidences of depressive and anxiety symptoms were 14.5% (19/191) and 3.1% (4/191) in the premenopausal -3 stage, respectively. The incidence increased in both menopausal transition and postmenopausal stage, with the highest incidence in the +1c stage [20.6% (155/751) and 8.8% (66/751), respectively]. However, these differences were not statistically significant (all P>0.05). Depressive symptoms were highest in the ≥60-<65 age group [20.8% (74/355)], and anxiety symptoms were highest in the ≥50-<55 age group [8.2% (62/754)]; but there were no statistical significances between different age groups and depressive and anxiety symptoms (all P>0.05). Multivariable analysis showed that high body mass index, low education status, and poor health status were independently associated with depressive symptoms (all P<0.05), and that poor health status, trouble falling asleep, and early awakening were independently associated with anxiety symptoms (all P<0.01). Conclusions: Depressive and anxiety symptoms are more common during menopausal transition and postmenopausal stage compared with reproductive stage. Depressive symptoms are more common than anxiety symptoms. To screen and assess depressive and anxiety symptoms in perimenopausal women is essential, especially for women with high risk factors.

Gel self-assembly of lanthanum aminopolycarboxylates with skeleton structures and adsorptions of gases

Lanthanum aminopolycarboxylates 1–3 have been isolated by gel self-assembly and fully characterized. La-EDTA 3 possesses 5.8 Å diameter tunnels inside the crystals, which can selectively adsorb very small amount of O2 without H2, N2, CH4 and CO2.

Effect of a high-concentrate diet on milk components and mammary health in Holstein dairy cows

In order to evaluate the milk yield, milk quality, and health of dairy cows fed a high-concentrate (HC) diet, eight lactating Holstein dairy cattle were randomly assigned to HC or low-concentrate (LC) diet groups and fed for 50 days, and the auto-control studying before and after treatment with the two diets was used. During the experiment, plasma and milk samples were collected and measured. With regard to milk component, HC feeding led to higher milk production (P < 0.05), but significantly lower milk protein percentage (P < 0.05), milk protein yield (P < 0.05), and milk fat percentage (P < 0.05) throughout the five periods than LC feeding. Milk somatic cell count and N-acetyl-D-glucosaminidase activity (P < 0.01) were higher than those observed under LC feeding. mRNA expression levels of interleukin-8 (IL-8), C-C motif chemokine ligand (CCL5), and lactalbumin alpha (α-LA) were investigated by qPCR and found to be significantly lower (P < 0.01) in cattle fed the HC diet. The amino acid content was analyzed by high performance liquid chromatography (HPLC), and the content of Asp (P < 0.01), Gln (P < 0.01), Ala (P < 0.05), Leu (P < 0.05), Lys (P < 0.05), and Ile (P < 0.01) was significantly lower in the HC group, whereas the content of Arg (P < 0.05) and Phe (P < 0.01) was significantly higher. These results suggest that the HC diet might have an important influence on mammary health. The amino acid content was lower, suggesting that depletion of amino acids, resulting in depleted milk protein, affects milk quality.

Endogenous LPS alters liver GH/IGF system gene expression and plasma lipoprotein lipase in goats

Endotoxin lipopolysaccharide (LPS) affects the ruminant health and animal performance. The main purposes of this study were to investigate the potential effects of GH/IGF system and lipoprotein lipase (LPL) concentration on resistance the circulating LPS concentration increased in liver with high concentrate diet treatment. Non-lactating goats were randomly allocated to two groups: a high-concentrate diet (HCD) or a low-concentrate diet (LCD) in cross over design and the blood collection at different time points after feeding at the end of the experiment. The average rumen pH was significantly reduced (P<0.05), but the duration with pH was not more than 120 min in the HCD group. The plasma LPL concentration was significantly raised (P<0.05). However, from 2 h onwards, LPS concentration was significantly reduced (P<0.01) in the HCD group compared with LCD group. In addition, the plasma IGF1 concentration and the hepatic insulin-like growth factor-1 receptor (IGF1R) mRNA expression were markedly reduced (P<0.05). However, growth hormone (GH) secretion at 15, 30, and 45 min after feeding and growth hormone receptor (GHR) mRNA expression in the liver was significantly increased (P<0.05) in HCD group. The correlation analysis showed that the plasma LPL concentration was positively correlated with hepatic GHR mRNA expression (P<0.05). Conversely, the plasma LPS concentration was negatively correlated with LPL concentration (P<0.05). These findings reveal that alterations in GH/IGF system function in response to a high-concentrate diet are accompanied by corresponding changes in systemic LPL in non-lactating goats' liver in presence of endogenous LPS stress.

Effects of maturity stages on the nutritive composition and silage quality of whole crop wheat

The changes in yields and nutritive composition of whole crop wheat (Triticum aestivum L.) during maturation and effects of maturity stage and lactic acid bacteria (LAB) inoculants on the fermentation quality and aerobic stability were investigated under laboratory conditions. Whole crop wheat harvested at three maturation stages: flowering stage, milk stage and dough stage. Two strains of LAB (Lactobacillus plantarum: LAB1, Lactobacillus parafarraqinis: LAB2) were inoculated for wheat ensiling at 1.0×10⁵ colony forming units per gram of fresh forage. The results indicated that wheat had higher dry matter yields at the milk and dough stages. The highest water-soluble carbohydrates content, crude protein yields and relative feed value of wheat were obtained at the milk stage, while contents of crude fiber, neutral detergent fiber and acid detergent fiber were the lowest, compared to the flowering and dough stages. Lactic acid contents of wheat silage significantly decreased with maturity. Inoculating homofermentative LAB1 markedly reduced pH values and ammonia-nitrogen (NH₃-N) content (p<0.05) of silages at three maturity stages compared with their corresponding controls. Inoculating heterofermentative LAB2 did not significantly influence pH values, whereas it notably lowered lactic acid and NH₃-N content (p<0.05) and effectively improved the aerobic stability of silages. In conclusion, considering both yields and nutritive value, whole crop wheat as forage should be harvested at the milk stage. Inoculating LAB1 improved the fermentation quality, while inoculating LAB2 enhanced the aerobic stability of wheat silages at different maturity stages.

Comparable efficacy of self-monitoring of quantitative urine glucose with self-monitoring of blood glucose on glycaemic control in non-insulin-treated type 2 diabetes

AIM

To assess whether self-monitoring of quantitative urine glucose or blood glucose is effective, convenient and safe for glycaemic control in non-insulin treated type 2 diabetes.

METHODS

Adults with non-insulin treated type 2 diabetes were recruited and randomized into three groups: Group A, self-monitoring with a quantitative urine glucose meter (n = 38); Group B, self monitoring with a blood glucose meter (n=35); Group C, the control group without self monitoring (n=35). All patients were followed up for six months, during which identical diabetes care was provided.

RESULTS

There was a significant decrease in HbA1c within each group (p < 0.05). At the study conclusion, mean changes in HbA1c from baseline were -1.9% for Group A, -1.5% for Group B and -1.0% for Group C, and the proportion of patients achieving HbA1c ≤ 6.5% were 38.9%, 35.3% and 20.0% respectively. However, no significant differences between the groups were found. The average monitoring frequency was significantly higher in Group A than in Group B. The incidence of hypoglycaemia and quality of life scores were similar between the groups.

CONCLUSIONS

This study suggests that self-monitoring of urine glucose has comparable efficacy on glycaemic control, and facilitates better compliance than blood self monitoring, without influencing the quality of life or risk of hypoglycaemia.

Isolation and characterization of a novel lectin from the mushroom Armillaria luteo-virens

From the dried fruiting bodies of the mushroom Armillaria luteo-virens, a dimeric lectin with a molecular mass of 29.4 kDa has been isolated. The purification procedure involved (NH(4))(2)SO(4) precipitation, ion exchange chromatography on DEAE-cellulose, CM-cellulose, and Q-Sepharose, and gel filtration by fast protein liquid chromatography on Superdex 75. The hemagglutinating activity of the lectin could not be inhibited by simple sugars but was inhibited by the polysaccharide inulin. The activity was stable up to 70 degrees C but was acid- and alkali-labile. Salts including FeCl(3), AlCl(3), and ZnCl(2) inhibited the activity whereas MgCl(2), MnCl(2), and CaCl(2) did not. The lectin stimulated mitogenic response of mouse splenocytes with the maximal response achieved by 1microM lectin. Proliferation of tumor cells including MBL2 cells, HeLa cells, and L1210 cells was inhibited by the lectin with an IC(50) of 2.5, 5, and 10 microM, respectively. However, proliferation of HepG2 cells was not affected. The novel aspects of the isolated lectin include a novel N-terminal sequence, fair thermostability, acid stability, and alkali stability, together with potent mitogenic activity toward spleen cells and antiproliferative activity toward tumor cells.

Effects of hypoxia and complement activation on lung hemodynamics and fluid exchanges in unanesthetized goats

The effects of hypoxia and zymosan-activated plasma (ZAP) on lung hemodynamics and fluid exchange were studied in unanesthetized goats. Hypoxia produced a sustained increase in pulmonary arterial pressure (PPA), but had no effect on lung lymph flow and protein content. Following ZAP infusion there was an early phase of leukopenia and marked pulmonary hypertension followed by a phase characterized by a modest increase in the flow of protein-rich lung lymph. When ZAP was infused at a simulated altitude of 4,000 m, there was a further increase in PPA followed by pulmonary vasodilatation, and about 1 h later it was almost back to the control level. No obvious difference in lung lymph flow and protein content was observed between the groups treated with ZAP alone and ZAP plus hypoxia. We conclude that infusion of ZAP into hypoxic animals reduces pulmonary vasoconstriction and that the increase in pulmonary microvascular permeability associated with ZAP is not enhanced by hypoxic conditions occurring at a simulated altitude of 4,000 m.