Prevalence and consistency of low breath H2 excretion following lactulose ingestion

The clinical use of the H₂ breath test is limited by the finding that a variable fraction of the population fails to excrete appreciable H₂ during colonic carbohydrate fermentation. Therefore, we assessed the ability to increase breath H₂ excretion in 371 patients (224 female, 147 male) by administering the nonabsorbable sugar lactulose. Following 12 g of lactulose, 27% of 94 patients did not increase their breath H₂ concentration over 20 ppm and were considered low H₂ excretors. Ingestion of 20 g of lactulose in 277 patients yielded a frequency of low H₂ excretors of 14%. Six of 10 patients that were low H₂ excretors after 12 g of lactulose increased their breath H₂ levels over 20 ppm when tested with 20 g. In 35 patients tested with the same amount of lactulose on two separate occasions, the subject frequently altered his or her H₂ producing status over a period of a few weeks. Low H₂ excretors had a significantly higher breath CH₄ concentration, both fasting (22 ± 34 ppm) and after lactulose (51 ± 58 ppm) compared to the remaining patients (5 ± 13 ppm and 16 ± 40 ppm, respectively). While the mean age of low excretors (54 ± 17 years) was significantly higher than the others (44 ± 17 years), no difference was found for sex prevalence and stool pH. This study demonstrates that respiratory H₂ excretion following lactulose ingestion is not consistent and suggests that the application of too restrictive criteria could lead to improper interpretation of the H₂ breath test.     

Relationship between methane production and breath hydrogen excretion in lactose-malabsorbing individuals

Recent studies have shown reduced breath hydrogen (H₂) excretion in methane (CH₄)-producing healthy individuals following ingestion of lactulose. This questions the reliability of the breath hydrogen test (BHT) in CH₄ excretors, but the relationship between CH₄ and H₂ excretion in other clinical applications of the BHT is not known. We reviewed BHT results in two groups of subjects: (1) 385 children tested for lactose malabsorption in a hospital setting, and (2) 109 lactose-malabsorbing patients tested with a home kit. The percentage of lactose malabsorbers in group 1 (51%) was the same regardless of CH₄-producing status (P=0.97). The BHT data from group 2 showed a positive correlation (r=0.6, P<0.000001) between the magnitude of the rise in CH₄ and H₂ concentrations, and the H₂ excretion curves were significantly higher in the CH₄-producing individuals. We conclude that attention to CH₄-producing status is not necessary in the interpretation of the lactose BHT.     

Helicobacter pylori is associated with alterations in intestinal gas profile among patients with nonulcer dyspepsia

The pathogenesis of nonulcer dyspepsia (NUD) is unknown. Gas and postprandial bloating are frequent symptoms. The role ofHelicobacter pylori (HP) in the pathogenesis of NUD is controversial. We studied the intestinal gas profile of NUD patients (N=34) at baseline and after lactulose administration. The prevalence of hydrogen and methane producers was similar among HP+ and HP– patients. Breath H₂ concentrations in response to lactulose showed significantly greater rise among HP+ subjects (P<0.0001). HP positivity was associated with higher total breath excretion for H₂ and methane combined (2984±1038 vs 1776±521 ppm/hr) compared to HP– subjects (P<0.05). There was no correlation between peak H₂ and methane levels. The role of alterations in intestinal gas in producing symptoms in HP+ patients with NUD needs further investigation.     

Lactulose Mediates Suppression of Dextran Sodium Sulfate-Induced Colon Inflammation by Increasing Hydrogen Production

Background

Molecular hydrogen (H₂) is a potent antioxidant and able to protect organs from oxidative stress injuries. Orally administered lactulose, a potent H₂ inducer, is digested by colon microflora and significantly increases H₂ production, indicating its potential anti-inflammatory action.

Objective

To evaluate the anti-inflammatory effects of lactulose on dextran sodium sulfate (DSS)-induced colitis in mice.

Methods

Mice were randomly assigned into seven groups, receiving regular distilled water, H₂-rich saline (peritoneal injection), DSS, oral lactulose (0.1, 0.15, 0.2 ml/10 g, respectively), and lactulose (0.2 ml/10 g) + oral antibiotics. The mouse model of human ulcerative colitis was established by supplying mice with water containing DSS. The H₂ breath test was used to determine the exhaled H₂ concentration. Body weight, colitis score, colon length, pathological features and tumor necrosis factor alpha (TNF-α), interleukin-1β (IL-1β), maleic dialdehyde (MDA) and marrow peroxidase (MPO) levels in colon lesions were evaluated.

Results

After 7 days, DSS-induced loss of body weight, increase of colitis score, shortening of colon length, pathological changes and elevated levels of TNF-α, IL-1β, MDA, and MPO in colon lesions, were significantly suppressed by oral lactulose administration and intraperitoneally injected H₂-rich saline. Ingestion of antibiotics significantly compromised the anti-inflammatory effects of lactulose. The H₂ breath test showed that lactulose administration significantly induced hydrogen production and that antibiotics administration could inhibit H₂ production.

Conclusion

Lactulose can prevent the development of DSS-induced colitis and alleviate oxidative stress in the colon, as measured by MDA and MPO, probably by increasing endogenous H₂ production.     

Efficacy of lactulose plus <Superscript>13</Superscript>C-acetate breath test in the diagnosis of gastrointestinal motility disorders

Background: Background: We designed a new method of measuring gastric emptying and orocecal transit time (OCTT) at the same time to assess the influence of gastric emptying upon OCTT. Methods: Twenty-five dyspeptic patients (6 men, 19 women) with a mean age of 64.8 years (range, 25–80 years) were studied. The patients received a liquid test meal, containing 100 mg of ¹³C-acetate and 12 g of lactulose, while they were in the sitting position after an overnight fast. Breath samples were collected at 10-min intervals of 120 min and both ¹³CO₂ and hydrogen (H₂) levels were measured. Subsequently, H₂ concentrations were measured at 30-min intervals, for a total of 240 min. Results: The results of gastric emptying were expressed as the time of peak ¹³CO₂ excretion. OCTT was defined as the period between the ingestion of lactulose and a H₂ peak rise of 5 ppm above the baseline value. The onset of H₂ enrichment in the breath began at 90–110 min, whereas ¹³CO₂ levels increased from the beginning, with peak enrichment values being reached after 60–80 min. OCTT was related to ¹³CO₂ peak time. In 5 of the 25 patients, H₂ breath enrichment in the 10-min sample was more than 5 ppm over the baseline value. All these 5 patients had double or triple peaks in serial breath H₂ concentrations. Conclusions: The combination of the lactulose hydrogen breath test (LHBT) with the ¹³C-acetate breath test, which requires only breath samples, provides us with much information on the gastrointestinal tract; gastric emptying, OCTT, bacterial overgrowth in the small intestine, colonic fermentation, and oropharyngeal flora. The ¹³C-acetate breath test can be useful as an adjuvant test when LHBT is performed for measuring OCTT. Received: March 5, 2001 / Accepted: October 5, 2001     

Hydrogen- and Methane-Based Breath Testing and Outcomes in Patients With Heart Failure

BackgroundRecent evidence endorses gut microbiota dysregulation in the pathophysiology of heart failure (HF). Small intestinal bacterial overgrowth (SIBO) might be present in HF and associated with poor clinical outcomes. Lactulose breath testing is a simple noninvasive test that has been advocated as a reliable indicator of SIBO. In patients with HF, we aimed to evaluate the association with clinical outcomes of the exhaled hydrogen (H₂) and methane (CH₄) concentrations through the lactulose breath test.Methods and ResultsWe included 102 patients with HF in which lactulose SIBO breath tests were assessed. Cumulative gas was quantified by the area under the receiver operating characteristic curve of CH₄ (AUC-CH₄) and H₂ (AUC-H₂). Clinical end points included the composite of all-cause death with either all-cause or HF hospitalizations, recurrent all-cause hospitalizations, and recurrent HF hospitalizations. Medians (interquartile ranges) of AUC-H₂ and AUC-CH₄ were 1290 U (520-2430) and 985 U (450-2120), respectively. In multivariable analysis, AUC-H₂ (per 1000 U) was associated with all-cause death/all-cause hospitalization (hazard ratio [HR] 1.21, 95% CI 1.04–1.40; P = .012), all-cause death/HF hospitalization (HR 1.20, 95% CI 1.03–1.40; P = .021), and an increase in the rate of recurrent all-cause (incidence rate ratio [IRR] 1.31, 95% CI 1.14–1.51; P < .001) and HF (IRR 1.41, 95% CI 1.15–1.72; P = .001) hospitalizations. AUC-CH₄ was not associated with any of these end points.ConclusionsAUC-H₂, a safe and noninvasive method for SIBO estimation, is associated with higher risk of long-term adverse clinical events in patients with HF. In contrast, AUC-CH₄ did not show any prognostic value.     

Differentiating biotic from abiotic methane genesis in hydrothermally active planetary surfaces

Molecular hydrogen (H₂) is derived from the hydrothermal alteration of olivine-rich planetary crust. Abiotic and biotic processes consume H₂ to produce methane (CH₄); however, the extent of either process is unknown. Here, we assess the temporal dependence and limit of abiotic CH₄ related to the presence and formation of mineral catalysts during olivine hydrolysis (i.e., serpentinization) at 200 °C and 0.03 gigapascal. Results indicate that the rate of CH₄ production increases to a maximum value related to magnetite catalyzation. By identifying the dynamics of CH₄ production, we kinetically model how the H₂ to CH₄ ratio may be used to assess the origin of CH₄ in deep subsurface serpentinization systems on Earth and Mars. Based on our model and available field data, low H₂/CH₄ ratios (less than approximately 40) indicate that life is likely present and active.     

Formaldehyde activation factor, tetrahydromethanopterin, a coenzyme of methanogenesis

An oxygen-labile formaldehyde activation factor (FAF) was isolated in highly purified form by use of anoxic fractionation procedures. The molecular weight of FAF was determined to be 776 and that of methanopterin (MPT) 772 by fast-atom-bombardment mass spectrometry (FABMS). High-resolution FABMS measurements on MPT and FAF indicated molecular formulas of C₃₀H₄₁N₆O₁₆P and C₃₀H₄₅N₆O₁₆P, respectively. The presence of phosphorus was confirmed by 100-MHz ³¹P NMR. The 360-MHz ¹H NMR spectrum of FAF in deuterium oxide was similar to that of MPT. A functional relationship between MPT and FAF was documented; both compounds stimulated the reductive demethylation of 2-(methylthio)ethanesulfonic acid (CH₃-S-CoM) to CH₄ when formaldehyde oxidation provided a source of electrons, and FAF replaced MPT in the CH₃-S-CoM-stimulated conversion of CO₂ to CH₄ under H₂ (the RPG effect). MPT was enzymically converted to FAF during the reduction of CH₃-S-CoM, and HCHO to CH₄ under H₂. Evidence indicates that FAF is tetrahydromethanopterin.     

D-Xylose hydrogen breath tests compared to absorption kinetics in human patients with and without malabsorption

Thed-xylose breath H₂ test may be useful in characterizing intestinal absorptive function. Our aim was to determine whether breath H₂ followingd-xylose administration reflects the extent to which thed-xylose is absorbed by comparing it to a kinetic model ofd-xylose absorption. Twenty-five subjects were studied. They ingested 15 gd-xylose on the first day and 25 gd-xylose on the third day. On the second day they received 10 g intravenousd-xylose along with 15 g oral lactulose. Multiple serum and urine samples were obtained ford-xylose content to calculate its rate constants and extent of absorption by multicompartmental analysis. Breath H₂ determinations were obtained every 15 min for 3 hr following the 15 gd-xylose and lactulose ingestion. Peak breath H₂ concentration correlated with extent of absorption (r=–0.787,P<0.001),K ₀, the rate constant for nonabsorptive loss (r=0.744,P<0.001), and 5-hr urine content (r=–0.705,P<0.001). Area under the breath H₂ curve also correlated with these parameters: extent of absorption (r=–0.770,P<0.001),K ₀ (r=0.662,P<0.001), 5-hr urine content (r=–0.629,P<0.012). Peakd-xylose breath H₂ to peak lactulose breath H₂ showed no correlation with extent of absorption. The extent of absorption was higher with the 15-g dose than the 25-g dose in all patients tested (P<0.01). This was the result of decreased nonabsorptive loss (lowerK ₀), as the rate constant for absorption,K _a , was not statistically different (P>0.05). Peakd-xylose breath H₂ can be used as an inverse estimate ofd-xylose absorption. Lactulose breath H₂ cannot be used as a standard for comparison ford-xylose. The three compartment kinetic model ford-xylose absorption with passive absorption of this carbohydrate is supported by similar rate constants for absorption for the twod-xylose doses used.d-xylose at 15 g may be a more appropriate dose than 25 g for H₂ breath testing as it does not lead to increased nonabsorptive losses.Supported in part by grant RR0048, National Institutes of Health, National Center for Research Resources.     

Unusual Dependence of the Diamond Growth Rate on the Methane Concentration in the Hot Filament Chemical Vapor Deposition Process

Although the growth rate of diamond increased with increasing methane concentration at the filament temperature of 2100 °C during a hot filament chemical vapor deposition (HFCVD), it decreased with increasing methane concentration from 1% CH₄ –99% H₂ to 3% CH₄ –97% H₂ at 1900 °C. We investigated this unusual dependence of the growth rate on the methane concentration, which might give insight into the growth mechanism of a diamond. One possibility would be that the high methane concentration increases the non-diamond phase, which is then etched faster by atomic hydrogen, resulting in a decrease in the growth rate with increasing methane concentration. At 3% CH₄ –97% H₂, the graphite was coated on the hot filament both at 1900 °C and 2100 °C. The graphite coating on the filament decreased the number of electrons emitted from the hot filament. The electron emission at 3% CH₄ –97% H₂ was 13 times less than that at 1% CH₄ –99% H₂ at the filament temperature of 1900 °C. The lower number of electrons at 3% CH₄ –97% H₂ was attributed to the formation of the non-diamond phase, which etched faster than diamond, resulting in a lower growth rate.     

Usefulness of the double-balloon enteroscope in colonoscopies performed in patients with previously failed colonoscopy

Jejunal flora, bile acid deconjugation, and breath hydrogen (H₂) and methane (CH₄) excretion were studied in 22 Billroth II (BII)-operated patients with chronic postprandial symptoms, dumping (9), vomiting (7), pain (10), and diarrhoea (14). Sixteen were below 90% of desirable weight. Two control groups were included, one comprising 5 symptom-free, BII-operated volunteers and another comprising 12 healthy, unoperated volunteers. The numbers of bacteria recovered from jejunal secretions in the postgastrectomy patients did not differ significantly from those recovered in the symptom-free BII-operated controls but were significantly lower in the unoperated controls. Production of fermentation gas in anaerobic media supplemented with carbohydrates occurred in 17 of 22 postgastrectomy patients and in 4 of 5 BII-operated controls but in none of the unoperated controls. Bacterial bile acid decon-jugating activity did not differ significantly between the postgastrectomy patients and the BII-operated controls but was significantly lower in the unoperated controls. Breath H₂ excretion after glucose ingestion was significantly higher in the postgastrectomy patients than in both the BII-operated and the unoperated controls. The addition of pectin or guar gum to the glucose meal largely prevented postprandial symptoms and breath hydrogen excretion. Six out of 12 postgastrectomy patients treated with metronidazole recorded symptomatic effects, mainly on diarrhoea. Our findings indicate that jejunal bacterial overgrowth may be a major cause of the symptoms in some postgastrectomy patients. The tests available for demonstration of small-bowel bacterial overgrowth, perhaps with the exception of the glucose H₂ breath test, did not differentiate satisfactorily between symptom-producing and non-symptom-producing abnormal jejunal flora. Thus these tests may seem to have a limited practical diagnostic value in such patients.     

Impact of age,sex, race,and functional complaints on hydrogen (H2) production

In order to evaluate factors that may influence H₂ generation, the effects of age, sex, race, and functional complaints on breath H₂ were studied in 62 subjects. These included 34 young hospital employees, 17 healthy ambulatory elderly subjects, and 11 patients with functional bowel disease. The ability to produce H₂ was defined by an increase in breath H₂ to greater than 20 parts per million within 4 hr of ingesting 10 g of the nonabsorbable sugar lactulose. Overall, 21% of subjects were nonproducers, and the incidence of nonproduction did not vary among the groups. The elderly subjects had significantly greater breath H₂ concentrations than the younger subjects at 150 minutes (P<0.05). Sex, race, and functional complaints did not influence H₂ production. These findings indicate that patient's age and potential inability to make H₂ need to be considered in the routine interpretation of H₂ breath tests.     

Rapid Growth of Nanostructured Diamond Film on Silicon and Ti–6Al–4V Alloy Substrates

Nanostructured diamond (NSD) films were grown on silicon and Ti–6Al–4V alloy substrates by microwave plasma chemical vapor deposition (MPCVD). NSD Growth rates of 5 μm/h on silicon, and 4 μm/h on Ti–6Al–4V were achieved. In a chemistry of H₂/CH₄/N₂, varying ratios of CH₄/H₂ and N₂/CH₄ were employed in this research and their effect on the resulting diamond films were studied by X-ray photoelectron spectroscopy, Raman spectroscopy, scanning electron microscopy, and atomic force microscopy. As a result of modifying the stock cooling stage of CVD system, we were able to utilize plasma with high power densities in our NSD growth experiments, enabling us to achieve high growth rates. Substrate temperature and N₂/CH₄ ratio have been found to be key factors in determining the diamond film quality. NSD films grown as part of this study were shown to contain 85% to 90% sp³ bonded carbon.     

Thermal Stability and Sublimation Pressures of Some Ruthenocene Compounds

We set out to study the use of a series of ruthenocenes as possible and promising sources for ruthenium and/or ruthenium oxide film formation.The thermal stability of a series of ruthenocenes, including (η⁵-C₅H₄R)(η⁵-C₅H₄R´)Ru (1), R = R´ = H (3), R = H, R´ = CH₂NMe₂ (5), R = H, R´= C(O)Me (6), R = R´ = C(O)Me (7), R = H, R´ = C(O)(CH₂)₃CO₂H (8), R = H, R´ = C(O)(CH₂)₂CO₂H (9), R = H, R´ = C(O)(CH₂)₃CO₂Me (10), R = H, R´= C(O)(CH₂)₂CO₂Me (11), R = R´ = SiMe₃), (η⁵-C₄H₃O-2,4-Me₂)₂Ru (2), and (η⁵-C₅H₅-2,4-Me₂)₂Ru (4) was studied by thermogravimetry. From these studies, it could be concluded that 1–4, 6 and 9–11 are the most thermally stable molecules. The sublimation pressure of these sandwich compounds was measured using a Knudsen cell. Among these, the compound 11 shows the highest vapor pressure.     

Nonenzymatic and enzymatic hydrolysis of alkyl halides: A theoretical study of the SN2 reactions of acetate and hydroxide ions with alkyl chlorides

The S_N2 displacements of chloride ion from CH₃Cl, C₂H₅Cl, and C₂H₄Cl₂ by acetate and hydroxide ions have been investigated, using ab initio molecular orbital theory at the HF/6–31+G(d), MP2/6–31+G(d), and MP4/6–31+G(d) levels of theory. The central barriers (calculated from the initial ion–molecule complex) of the reactions, the differences of the overall reaction energies, and the geometries of the transition states are compared. Essential stereochemical changes before and after the displacement reactions are described for selected cases. The gas phase reactions of hydroxide with CH₃Cl, C₂H₅Cl, and C₂H₄Cl₂ have no overall barrier, but there is a small overall barrier for the reactions of acetate with CH₃Cl, C₂H₅Cl, and C₂H₄Cl₂. A self-consistent reaction field solvation model was used to examine the S_N2 reactions between methyl chloride and hydroxide ion and between 1,2-dichloroethane and acetate in solution. As expected, the reactions in polar solvent have a large barrier. However, the transition state structures determined by ab initio calculations change only slightly in the presence of a highly polar solvent as compared with the gas phase. We also calibrated the PM3 method for future study of an enzymatic S_N2 displacement of halogen.     

Impaired absorptive capacity for carbohydrate in the aging human

Breath hydrogen (H₂) analysis was utilized to determine whether intestinal absorption of carbohydrate might decline with age. Twenty-one healthy subjects (aged 65–89 years, mean age 79.1) and 19 control subjects (aged 20–64 years, mean age 35.6) were fed a meal containing 100 g carbohydrate after an overnight fast. Breath H₂ concentrations were analyzed in samples collected intermittently by the end-expiratory technique. A rise in breath H₂ concentration of 20 ppm over baseline was considered evidence of intestinal carbohydrate malabsorption: 7 of 21 aged and 0 of 19 control subjects excreted excess H₂ (P<0.02). Further testing of subjects with meals containing 25–200 g carbohydrate demonstrated a progressive reduction in absorptive capacity with advancing age, while young controls absorbed up to 200 g carbohydrate in a meal. In the group of older subjects carbohydrate malabsorption was not accompanied by clinical determinants of undernutrition. Subtle carbohydrate malabsorption should be considered when evaluating weight loss in old age and in fashioning nutritional programs for the elderly.Presented in part at the Annual Meeting of the American Federation for Clinical Research, Washington, DC, May 1979.This work was supported in part by a grant from the Overseas Shipholding Corp.     

Direct observation of reaction intermediates for a well defined heterogeneous alkene metathesis catalyst

Grafting of [W(NAr)(=CHtBu)(2,5-Me₂NC₄H₂)₂] on a silica partially dehydroxylated at 700°C (SiO_{2- (700)}) generates the corresponding monosiloxy complex [(SiO)W(NAr)(=CHtBu)(2,5-Me₂NC₄H₂)] as the major species (≈90%) along with [(SiO)W(NAr)(CH₂tBu)(2,5-Me₂NC₄H₂)₂], according to mass balance analysis, IR, and NMR studies. This heterogeneous catalyst displays good activity and stability in the metathesis of propene. Very importantly, solid state NMR spectroscopy allows observation of the propagating alkylidene as well as stable metallacyclobutane intermediates. These species have the same reactivity as the initial surface complex [(SiO)W(NAr)(=CHtBu)(2,5-Me₂NC₄H₂)], which shows that they are the key intermediates of alkene metathesis.     

Ultrafast photochemistry of methyl hydroperoxide on ice particles

Simulations show that photodissociation of methyl hydroperoxide, CH₃OOH, on water clusters produces a surprisingly wide range of products on a subpicosecond time scale, pointing to the possibility of complex photodegradation pathways for organic peroxides on aerosols and water droplets. Dynamics are computed at several excitation energies at 50 K using a semiempirical PM3 potential surface. CH₃OOH is found to prefer the exterior of the cluster, with the CH₃O group sticking out and the OH group immersed within the cluster. At atmospherically relevant photodissociation wavelengths the OH and CH₃O photofragments remain at the surface of the cluster or embedded within it. However, none of the 25 completed trajectories carried out at the atmospherically relevant photodissociation energies led to recombination of OH and CH₃O to form CH₃OOH. Within the limited statistics of the available trajectories the predicted yield for the recombination is zero. Instead, various reactions involving the initial fragments and water promptly form a wide range of stable molecular products such as CH₂O, H₂O, H₂, CO, CH₃OH, and H₂O₂.     

Numerical Simulation of Gas Phase Reaction for Epitaxial Chemical Vapor Deposition of Silicon Carbide by Methyltrichlorosilane in Horizontal Hot-Wall Reactor

Methyltrichlorosilane (CH₃SiCl₃, MTS) has good performance in stoichiometric silicon carbide (SiC) deposition and can be facilitated at relatively lower temperature. Simulations of the chemical vapor deposition in the two-dimensional horizontal hot-wall reactor for epitaxial processes of SiC, which were prepared from MTS-H₂ gaseous system, were performed in this work by using the finite element method. The chemistry kinetic model of gas-phase reactions employed in this work was proposed by other researchers. The total gas flow rate, temperature, and ratio of MTS/H₂ were the main process parameters in this work, and their effects on consumption rate of MTS, molar fraction of intermediate species and C/Si ratio inside the hot reaction chamber were analyzed in detail. The phenomena of our simulations are interesting. Both low total gas flow rate and high substrate temperature have obvious effectiveness on increasing the consumption rate of MTS. For all cases, the highest three C contained intermediates are CH₄, C₂H₄ and C₂H₂, respectively, while the highest three Si/Cl contained intermediates are SiCl₂, SiCl₄ and HCl, respectively. Furthermore, low total gas flow results in a uniform C/Si ratio at different temperatures, and reducing the ratio of MTS/H₂ is an interesting way to raise the C/Si ratio in the reactor.     

Coordination of {Mo142} Ring to La3+ Provides Elliptical {Mo134La10} Ring with a Variety of Coordination Modes

A 28-electron reduced C_2h-Mo-blue 34Ǻ outer ring diameter circular ring, [Mo₁₄₂O₄₂₉H₁₀(H₂O)₄₉(CH₃CO₂)₅(C₂H₅CO₂)]^30- (≡{Mo₁₄₂(CH₃CO₂)₅(C₂H₅CO₂)}) comprising eight carboxylate-coordinated (with disorder) {Mo₂} linkers and six defect pockets in two inner rings (four and three for each, respectively), reacts with La³⁺ in aqueous solutions at pH 3.5 to yield a 28-electron reduced elliptical C_i-Mo-blue ring of formula [Mo₁₃₄O₄₁₆H₂₀(H₂O)₄₆{La(H₂O)₅}₄{La(H₂O)₇}₄{LaCl₂(H₂O)₅}₂]^10- (≡{Mo₁₃₄La₁₀}), isolated as the Na₁₀[Mo₁₃₄O₄₁₆H₂₀(H₂O)₄₆{La(H₂O)₅}₄{La(H₂O)₇}₄{LaCl₂(H₂O)₅}₂]·144 H₂O Na⁺ salt. The elliptical structure of {Mo₁₃₄La₁₀} showing 36 and 31 Å long and short axes for the outer ring diameters is attributed to four (A-D) modes of LaO₉/LaO₇Cl₂ tricapped-trigonal-prismatic coordination (TTP) geometries. Two different LaO₂(H₂O)₇ and one LaO₂(H₂O)₂Cl₂ TTP geometries (as A-C modes) for each of two inner rings result from the coordination of all three defect pockets of the inner ring for {Mo₁₄₂(CH₃CO₂)₅(C₂H₅CO₂)}, and two LaO₄(H₂O)₅ TTP geometries (as D mode) result from the displacement of two (acetate/propionate-coordinated) binuclear {Mo₂} linkers with La³⁺ in each inner ring. The isothermal titration calorimetry (ITC) of the ring modification from circle to ellipsoid, showing the endothermic reaction of [La³⁺]/[{Mo₁₄₂(CH₃CO₂)₅(C₂H₅CO₂)}] = 6/1 with ΔH = 22 kJ⋅mol^-1, ΔS = 172 J⋅K^-1⋅mol^-1, ΔG = −28 kJ⋅mol^-1, and K = 9.9 × 10⁴ M^-1 at 293 K, leads to the conclusion that the coordination of the defect pockets to La³⁺ precedes the replacement of the {Mo₂} linkers with La³⁺. ¹³⁹La- NMR spectrometry of the coordination of {Mo₁₄₂(CH₃CO₂)₅(C₂H₅CO₂)} ring to La³⁺ is also discussed.