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1.
Nat Commun ; 13(1): 4832, 2022 08 17.
Article in English | MEDLINE | ID: mdl-35977954

ABSTRACT

A fundamental property of higher eukaryotes that underpins their evolutionary success is stable cell-cell cohesion. Yet, how intrinsic cell rheology and stiffness contributes to junction stabilization and maturation is poorly understood. We demonstrate that localized modulation of cell rheology governs the transition of a slack, undulated cell-cell contact (weak adhesion) to a mature, straight junction (optimal adhesion). Cell pairs confined on different geometries have heterogeneous elasticity maps and control their own intrinsic rheology co-ordinately. More compliant cell pairs grown on circles have slack contacts, while stiffer triangular cell pairs favour straight junctions with flanking contractile thin bundles. Counter-intuitively, straighter cell-cell contacts have reduced receptor density and less dynamic junctional actin, suggesting an unusual adaptive mechano-response to stabilize cell-cell adhesion. Our modelling informs that slack junctions arise from failure of circular cell pairs to increase their own intrinsic stiffness and resist the pressures from the neighbouring cell. The inability to form a straight junction can be reversed by increasing mechanical stress artificially on stiffer substrates. Our data inform on the minimal intrinsic rheology to generate a mature junction and provide a springboard towards understanding elements governing tissue-level mechanics.


Subject(s)
Actins , Actins/metabolism , Cell Adhesion/physiology , Elasticity , Rheology , Stress, Mechanical
3.
Phys Rev Lett ; 125(9): 097002, 2020 Aug 28.
Article in English | MEDLINE | ID: mdl-32915627

ABSTRACT

Charge density wave (CDW) correlations are prevalent in all copper-oxide superconductors. While CDWs in conventional metals are driven by coupling between lattice vibrations and electrons, the role of the electron-phonon coupling (EPC) in cuprate CDWs is strongly debated. Using Cu L_{3} edge resonant inelastic x-ray scattering, we study the CDW and Cu-O bond-stretching phonons in the stripe-ordered cuprate La_{1.8-x}Eu_{0.2}Sr_{x}CuO_{4+δ}. We investigate the interplay between charge order and EPC as a function of doping and temperature and find that the EPC is enhanced in a narrow momentum region around the CDW ordering vector. By detuning the incident photon energy from the absorption resonance, we extract an EPC matrix element at the CDW ordering vector of M≃0.36 eV, which decreases to M≃0.30 eV at high temperature in the absence of the CDW. Our results suggest a feedback mechanism in which the CDW enhances the EPC which, in turn, further stabilizes the CDW.

4.
Int J Phytoremediation ; 20(9): 909-913, 2018 Jul 29.
Article in English | MEDLINE | ID: mdl-29873532

ABSTRACT

The aquatic plant Hydrocotyle vulgaris was evaluated for its efficacy in removing prometryn from nutrient solution. Under optimized experimental conditions, up to 94.0% of the initial prometryn was removed from the hydroponic culture medium by H. vulgaris in 30 days. The concentration of prometryn decreased from the initial level of 0.55 ± 0.013 mg/L to 0.036 ± 0.001 mg/L at the end of the experimental period. The removal kinetics followed first-order kinetic equation (Ct = 0.4569e-0.09t). Half-life (t1/2) of prometryn was greatly shortened from 27.16 days (without plant) to 5.58 days (with H. vulgaris). Approximately 22% of the initial prometryn residue was found in H. vulgaris tissue, while 11.7% was degraded by the plant in 30 days. The metabolites of prometryn detected were 2,4-diamino-1,3,5-triazine (in the hydroponic culture medium) and 2,4,6-trihydroxy-1,3,5-triazine (in plant tissue) after 30 days. The results indicate that H. vulgaris can be used for phytoextraction of prometryn and could potentially be effective in removing other s-trazine pesticides from contaminated aquatic ecosystems.


Subject(s)
Centella , Prometryne , Biodegradation, Environmental , Ecosystem , Hydroponics , Wetlands
5.
Eur Rev Med Pharmacol Sci ; 21(19): 4446-4456, 2017 Oct.
Article in English | MEDLINE | ID: mdl-29077147

ABSTRACT

OBJECTIVE: The current study was to explore the effect of melatonin on osteoporosis and relevant mechanisms. MATERIALS AND METHODS: We performed micro-CT to detect bone microstructure and ELISA to detect the contents of osteocalcin (OCN) and bone alkaline phosphatase (BAP) in serum. Double fluorescence labeling of calcein and tetracycline and toluidine blue staining were used to determine morphological indexes of bone tissues. Alizarin red staining and Oil Red O staining were performed to recognize bone cells and adipocytes. RT-PCR was performed to determine the expression of osteoblast differentiation related genes. RESULTS: In the current study, data from micro-CT indicated that melatonin significantly increased the bone mass density (BMD), bone volume/tissue volume (BV/TV), trabecular number (Tb.N) and trabecular thickness (Tb.Th), and decreased the Structure Model Index (SMI) and trabecular Separation/Spacing (Tb.Sp) in elderly rats. Melatonin reduced calcium and phosphorus losses in urine and increased BAP and OCN levels in serum in elderly rats and increased bone formation rate (BFR) and bone mineralization rate (MAR) in elderly rats. Melatonin increased the number of osteoblasts in bone marrow and reduced the number of adipocytes in elderly rats. Melatonin also promoted the expression of osteogenic differentiation genes and suppressed the expression of adipogenic differentiation genes. CONCLUSIONS: WE suggest that melatonin could alleviate osteoporosis in aged rats' models probably by promoting osteoblast differentiation.


Subject(s)
Bone Marrow Cells/drug effects , Cell Differentiation/drug effects , Melatonin/pharmacology , Mesenchymal Stem Cells/drug effects , Osteoblasts/drug effects , Adipocytes/drug effects , Aging/pathology , Alkaline Phosphatase/metabolism , Animals , Bone and Bones/cytology , Bone and Bones/drug effects , Male , Osteocalcin/metabolism , Rats , Rats, Sprague-Dawley , Trabecular Meshwork/cytology , Trabecular Meshwork/drug effects
6.
Phys Rev Lett ; 118(2): 027002, 2017 Jan 13.
Article in English | MEDLINE | ID: mdl-28128591

ABSTRACT

X-ray diffraction was employed to study the evolution of the charge density wave (CDW) in Cu_{x}TiSe_{2} as a function of copper intercalation in order to clarify the relationship between the CDW and superconductivity. The results show a CDW incommensuration arising at an intercalation value coincident with the onset of superconductivity at around x=0.055(5). Additionally, it was found that the charge density wave persists to higher intercalant concentrations than previously assumed, demonstrating that the CDW does not terminate inside the superconducting dome. A charge density wave peak was observed in samples up to x=0.091(6), the highest copper concentration examined in this study. The phase diagram established in this work suggests that charge density wave incommensuration may play a role in the formation of the superconducting state.

7.
Prostate Cancer Prostatic Dis ; 20(1): 72-78, 2017 03.
Article in English | MEDLINE | ID: mdl-27698439

ABSTRACT

BACKGROUND: At the population level, obesity is associated with prostate cancer (PC) mortality. However, few studies analyzed the associations between obesity and long-term PC-specific outcomes after initial treatment. METHODS: We conducted a retrospective analysis of 4268 radical prostatectomy patients within the Shared Equal Access Regional Cancer Hospital (SEARCH) database. Cox models accounting for known risk factors were used to examine the associations between body mass index (BMI) and PC-specific mortality (PCSM; primary outcome). Secondary outcomes included biochemical recurrence (BCR) and castration-resistant PC (CRPC). BMI was used as a continuous and categorical variable (normal <25 kg/m2, overweight 25-29.9 kg/m2 and obese ⩾30 kg/m2). Median follow-up among all men who were alive at last follow-up was 6.8 years (interquartile range=3.5-11.0). During this time, 1384 men developed BCR, 117 developed CRPC and 84 died from PC. Hazard ratios were analyzed using competing-risks regression analysis accounting for non-PC death as a competing risk. RESULTS: On crude analysis, higher BMI was not associated with risk of PCSM (P=0.112), BCR (0.259) and CRPC (P=0.277). However, when BMI was categorized, overweight (hazard ratio (HR) 1.99, P=0.034) and obesity (HR 1.97, P=0.048) were significantly associated with PCSM. Obesity and overweight were not associated with BCR or CRPC (all P⩾0.189). On multivariable analysis adjusting for both clinical and pathological features, results were little changed in that obesity (HR=2.05, P=0.039) and overweight (HR=1.88, P=0.061) were associated with higher risk of PCSM, but not with BCR or CRPC (all P⩾0.114) with the exception that the association for overweight was no longer statistical significant. CONCLUSIONS: Overweight and obesity were associated with increased risk of PCSM after radical prostatectomy. If validated in larger studies with longer follow-up, obesity may be established as a potentially modifiable risk factor for PCSM.


Subject(s)
Obesity/complications , Prostatic Neoplasms/complications , Prostatic Neoplasms/mortality , Aged , Cancer Care Facilities , Databases, Factual , Hospital Mortality , Humans , Male , Middle Aged , Neoplasm Grading , Neoplasm Staging , Proportional Hazards Models , Prostatectomy/methods , Prostatic Neoplasms/epidemiology , Prostatic Neoplasms/surgery , Retrospective Studies , Risk Factors
8.
Bull Environ Contam Toxicol ; 96(4): 550-5, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26810796

ABSTRACT

2,4-bis(Isopropylamino)-6-methylthio-s-triazine (prometryn) poses a risk to aquatic environments in several countries, including China, where its use is widespread, particularly due to its chemical stability and biological toxicity. Vetiver grass (Chrysopogon zizanioides L.) was tested for its potential for phytoremediation of prometryn. Vetiver grass was grown in hydroponic media in a greenhouse, in the presence of prometryn, with appropriate controls. Plant uptake and removal of prometryn from the media were monitored for a period of 67 days. The results showed that the removal of the prometryn in the media was expedited by vetiver grass. The removal half-life (t1/2) was shortened by 11.5 days. Prometryn removal followed first-order kinetics (Ct = 1.8070e(-0.0601t)). This study demonstrated the potential of vetiver grass for the phytoremediation for prometryn.


Subject(s)
Chrysopogon/growth & development , Hydroponics/methods , Prometryne/analysis , Soil Pollutants/analysis , Biodegradation, Environmental , China , Chrysopogon/metabolism
9.
Dis Esophagus ; 29(6): 621-6, 2016 Aug.
Article in English | MEDLINE | ID: mdl-25951709

ABSTRACT

In the present study, we aimed to evaluate the expression of special AT-rich sequence-binding protein 1 (SATB1) in esophageal squamous cell carcinoma (ESCC) and assess the correlation between its expression and the clinicopathological features and prognosis of the disease. SATB1 expression in ESCC tissue was determined by using immunohistochemical analysis, quantitative real-time polymerase chain reaction, and western blot analysis. The relationship between SATB1 expression and clinicopathological features was examined by using the chi-squared test, and the survival rate was calculated by using the Kaplan-Meier survival curve. The correlation between the indicators and patient survival was estimated by using a Cox regression analysis. High SATB1 expression in was detected in 48.3% and 7.8% of ESCC and normal esophagus tissues (P < 0.05), respectively. SATB1 expression did not significantly correlate with clinicopathological features. The Kaplan-Meier curve indicated that patients with high SATB1 expression had significantly shorter survival than those with low SATB1 expression. In a multivariate Cox regression model, high SATB1 expression was identified as an independent prognostic factor for patients with ESCC. In conclusion, these results suggest that high SATB1 expression is predictive of poor prognosis in ESCC and may be a promising new candidate for targeted therapies for ESCC.


Subject(s)
Carcinoma, Squamous Cell/genetics , Esophageal Neoplasms/genetics , Matrix Attachment Region Binding Proteins/genetics , RNA, Messenger/metabolism , Adult , Aged , Blotting, Western , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/mortality , Esophageal Neoplasms/metabolism , Esophageal Neoplasms/mortality , Esophageal Squamous Cell Carcinoma , Female , Humans , Immunohistochemistry , Kaplan-Meier Estimate , Male , Matrix Attachment Region Binding Proteins/metabolism , Middle Aged , Multivariate Analysis , Pilot Projects , Prognosis , Proportional Hazards Models , Real-Time Polymerase Chain Reaction , Retrospective Studies
10.
Eur Rev Med Pharmacol Sci ; 19(7): 1305-14, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25912594

ABSTRACT

OBJECTIVE: To observe the effect of curcumin on the expression levels of nuclear factor κB-p65 (NF-κB-p65) and tumour necrosis factor α (TNF-α) in the nucleus pulposus in rats with lumbar intervertebral disc degeneration. And to investigate of the mechanism underlying the role of curcumin in decelerating the process of lumbar intervertebral disc degeneration. MATERIALS AND METHODS: The model of lumbar intervertebral disc degeneration was established in Sprague-Dawley (SD) rats followed by a curcumin treatment. The ultra-microstructure histomorphological variations in the lumbar intervertebral disc of SD rats were evaluated. The protein and gene expression levels of NF-κB-p65 and TNF-α in the lumbar intervertebral disc were measured. RESULTS: Magnetic resonance imaging (MRI) and histomorphology confirmed the establishment of a successful lumbar intervertebral disc degeneration model. The results from the MRI and the ultra-microstructures revealed a significant improvement in lumbar intervertebral disc degeneration in the curcumin-treated groups (low dose and high dose). No significant change was observed in the solvent control group treated with dimethyl sulfoxide (DMSO) alone. Based on the results of Western blot analysis and real-time PCR, the curcumin treatment (low dose and high dose) significantly reduced the expression levels of NF-κB-p65 and TNF-α in the lumbar intervertebral disc tissue compared with the groups without curcumin treatment and with the DMSO treatment alone. No significant difference, however, was observed between the low-dose and high-dose curcumin treatment groups. CONCLUSIONS: Curcumin may inhibit the activation of NF-κB by inhibiting the translocation of NF-κB-p65 and reducing the release of inflammatory factors which, thereby, decelerates the process of lumbar intervertebral disc degeneration.


Subject(s)
Curcumin/pharmacology , Intervertebral Disc Degeneration/drug therapy , Intervertebral Disc Degeneration/metabolism , Lumbar Vertebrae , NF-kappa B/antagonists & inhibitors , NF-kappa B/biosynthesis , Animals , Curcumin/therapeutic use , Gene Expression Regulation/drug effects , Intervertebral Disc Degeneration/pathology , Male , Rats , Rats, Sprague-Dawley , Transcription Factor RelA/biosynthesis , Treatment Outcome , Tumor Necrosis Factor-alpha/biosynthesis
11.
Braz. j. med. biol. res ; 47(6): 461-469, 06/2014. graf
Article in English | LILACS | ID: lil-709449

ABSTRACT

A previous study showed that BMP-2 (bone morphogenetic protein-2) and wear debris can separately support osteoclast formation induced by the receptor activator of NF-κB ligand (RANKL). However, the effect of BMP-2 on wear debris-induced osteoclast formation is unclear. In this study, we show that neither titanium particles nor BMP-2 can induce osteoclast formation in RAW 264.7 mouse leukemic monocyte macrophage cells but that BMP-2 synergizes with titanium particles to enhance osteoclast formation in the presence of RANKL, and that at a low concentration, BMP-2 has an optimal effect to stimulate the size and number of multinuclear osteoclasts, expression of osteoclast genes, and resorption area. Our data also clarify that the effects caused by the increase in BMP-2 on phosphorylated SMAD levels such as c-Fos expression increased throughout the early stages of osteoclastogenesis. BMP-2 and titanium particles stimulate the expression of p-JNK, p-P38, p-IkB, and P50 compared with the titanium group. These data suggested that BMP-2 may be a crucial factor in titanium particle-mediated osteoclast formation.


Subject(s)
Animals , Mice , /pharmacology , Cell Differentiation/drug effects , Macrophages/drug effects , Osteoclasts/metabolism , RANK Ligand/pharmacology , Titanium/pharmacology , Acid Phosphatase/pharmacology , Blotting, Western , Bone Resorption/metabolism , Cell Line, Tumor , Cell Survival , Drug Synergism , Enzyme-Linked Immunosorbent Assay , Gene Expression , Isoenzymes/pharmacology , Real-Time Polymerase Chain Reaction , Smad Proteins/metabolism , Tumor Necrosis Factor-alpha/isolation & purification
12.
Braz J Med Biol Res ; 47(6): 461-9, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24820069

ABSTRACT

A previous study showed that BMP-2 (bone morphogenetic protein-2) and wear debris can separately support osteoclast formation induced by the receptor activator of NF-κB ligand (RANKL). However, the effect of BMP-2 on wear debris-induced osteoclast formation is unclear. In this study, we show that neither titanium particles nor BMP-2 can induce osteoclast formation in RAW 264.7 mouse leukemic monocyte macrophage cells but that BMP-2 synergizes with titanium particles to enhance osteoclast formation in the presence of RANKL, and that at a low concentration, BMP-2 has an optimal effect to stimulate the size and number of multinuclear osteoclasts, expression of osteoclast genes, and resorption area. Our data also clarify that the effects caused by the increase in BMP-2 on phosphorylated SMAD levels such as c-Fos expression increased throughout the early stages of osteoclastogenesis. BMP-2 and titanium particles stimulate the expression of p-JNK, p-P38, p-IkB, and P50 compared with the titanium group. These data suggested that BMP-2 may be a crucial factor in titanium particle-mediated osteoclast formation.


Subject(s)
Bone Morphogenetic Protein 2/pharmacology , Cell Differentiation/drug effects , Macrophages/drug effects , Osteoclasts/metabolism , RANK Ligand/pharmacology , Titanium/pharmacology , Acid Phosphatase/pharmacology , Animals , Blotting, Western , Bone Resorption/metabolism , Cell Line, Tumor , Cell Survival , Drug Synergism , Enzyme-Linked Immunosorbent Assay , Gene Expression , Isoenzymes/pharmacology , Mice , Real-Time Polymerase Chain Reaction , Smad Proteins/metabolism , Tartrate-Resistant Acid Phosphatase , Tumor Necrosis Factor-alpha/isolation & purification
13.
Braz J Med Biol Res ; 46(10): 831-8, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24141610

ABSTRACT

Wear particles are phagocytosed by macrophages and other inflammatory cells, resulting in cellular activation and release of proinflammatory factors, which cause periprosthetic osteolysis and subsequent aseptic loosening, the most common causes of total joint arthroplasty failure. During this pathological process, tumor necrosis factor-alpha (TNF-α) plays an important role in wear-particle-induced osteolysis. In this study, recombination adenovirus (Ad) vectors carrying both target genes [TNF-α small interfering RNA (TNF-α-siRNA) and bone morphogenetic protein 2 (BMP-2)] were synthesized and transfected into RAW264.7 macrophages and pro-osteoblastic MC3T3-E1 cells, respectively. The target gene BMP-2, expressed on pro-osteoblastic MC3T3-E1 cells and silenced by the TNF-α gene on cells, was treated with titanium (Ti) particles that were assessed by real-time PCR and Western blot. We showed that recombinant adenovirus (Ad-siTNFα-BMP-2) can induce osteoblast differentiation when treated with conditioned medium (CM) containing RAW264.7 macrophages challenged with a combination of Ti particles and Ad-siTNFα-BMP-2 (Ti-ad CM) assessed by alkaline phosphatase activity. The receptor activator of nuclear factor-κB ligand was downregulated in pro-osteoblastic MC3T3-E1 cells treated with Ti-ad CM in comparison with conditioned medium of RAW264.7 macrophages challenged with Ti particles (Ti CM). We suggest that Ad-siTNFα-BMP-2 induced osteoblast differentiation and inhibited osteoclastogenesis on a cell model of a Ti particle-induced inflammatory response, which may provide a novel approach for the treatment of periprosthetic osteolysis.


Subject(s)
Bone Morphogenetic Protein 2/metabolism , Osteoblasts/metabolism , RNA, Small Interfering/metabolism , Titanium/adverse effects , Tumor Necrosis Factor-alpha/metabolism , Adenoviridae/genetics , Animals , Bone Morphogenetic Protein 2/genetics , Bone Resorption/genetics , Cell Differentiation , Cell Line , Gene Expression , Genetic Vectors/genetics , Osteoblasts/cytology , Osteoblasts/drug effects , RNA, Small Interfering/genetics , Tumor Necrosis Factor-alpha/genetics
14.
Braz. j. med. biol. res ; 46(10): 831-838, 24/set. 2013. tab, graf
Article in English | LILACS | ID: lil-688557

ABSTRACT

Wear particles are phagocytosed by macrophages and other inflammatory cells, resulting in cellular activation and release of proinflammatory factors, which cause periprosthetic osteolysis and subsequent aseptic loosening, the most common causes of total joint arthroplasty failure. During this pathological process, tumor necrosis factor-alpha (TNF-α) plays an important role in wear-particle-induced osteolysis. In this study, recombination adenovirus (Ad) vectors carrying both target genes [TNF-α small interfering RNA (TNF-α-siRNA) and bone morphogenetic protein 2 (BMP-2)] were synthesized and transfected into RAW264.7 macrophages and pro-osteoblastic MC3T3-E1 cells, respectively. The target gene BMP-2, expressed on pro-osteoblastic MC3T3-E1 cells and silenced by the TNF-α gene on cells, was treated with titanium (Ti) particles that were assessed by real-time PCR and Western blot. We showed that recombinant adenovirus (Ad-siTNFα-BMP-2) can induce osteoblast differentiation when treated with conditioned medium (CM) containing RAW264.7 macrophages challenged with a combination of Ti particles and Ad-siTNFα-BMP-2 (Ti-ad CM) assessed by alkaline phosphatase activity. The receptor activator of nuclear factor-κB ligand was downregulated in pro-osteoblastic MC3T3-E1 cells treated with Ti-ad CM in comparison with conditioned medium of RAW264.7 macrophages challenged with Ti particles (Ti CM). We suggest that Ad-siTNFα-BMP-2 induced osteoblast differentiation and inhibited osteoclastogenesis on a cell model of a Ti particle-induced inflammatory response, which may provide a novel approach for the treatment of periprosthetic osteolysis.


Subject(s)
Animals , /metabolism , Osteoblasts/metabolism , RNA, Small Interfering/metabolism , Titanium/adverse effects , Tumor Necrosis Factor-alpha/metabolism , Adenoviridae/genetics , /genetics , Bone Resorption/genetics , Cell Differentiation , Cell Line , Gene Expression , Genetic Vectors/genetics , Osteoblasts/cytology , Osteoblasts/drug effects , RNA, Small Interfering/genetics , Tumor Necrosis Factor-alpha/genetics
15.
Tissue Antigens ; 68(4): 339-43, 2006 Oct.
Article in English | MEDLINE | ID: mdl-17026471

ABSTRACT

The human leukocyte antigen (HLA)-B*5516 allele differs from the B*5502 by a single 97 T --> C substitution (His to Tyr at position 33) in exon 2. The B*1313 allele results from 419 T --> A and 420 A --> C substitutions, encoding a Leu to Tyr substitution at 140 in exon 2 of the B*1301 allele. The B*9512 allele differs from B*1502 by a single 360 G --> C substitution (Gln to His at 120) in exon 3. The DRB1*1457 allele appears to be a hybrid molecule generated by recombination between the DRB1*13 and DRB1*14 alleles. The serological equivalents of these new alleles are HLA-B22, -B13, -B15, and DR13, respectively. Family studies detected two rare haplotypes: A*11, B*9512, DRB1*14 and A*24, B*52, Cw*07, DRB1*1457, DRB3*020201, DQB1*050301. The gene frequencies of these alleles in the Chinese population are less than 0.0001.


Subject(s)
Alleles , HLA-B Antigens/genetics , HLA-DR Antigens/genetics , Amino Acid Sequence , Antibodies/blood , Antibody Specificity/genetics , Asian People/genetics , Cytotoxicity Tests, Immunologic , Epitopes/genetics , Epitopes/immunology , Genotype , HLA-B Antigens/blood , HLA-B Antigens/immunology , HLA-DR Antigens/blood , HLA-DR Antigens/immunology , HLA-DRB1 Chains , Humans , Molecular Sequence Data , Sequence Analysis, DNA
16.
Phys Rev E Stat Nonlin Soft Matter Phys ; 64(2 Pt 1): 021512, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11497594

ABSTRACT

We are interested in the spatial density of a molecular fluid in the presence of a solute of arbitrary size and shape. The density functional is written as the sum of a F0[rho(r)] that effectively describes small deviations around the uniform density, plus an energy density part that is responsible for formation of liquid-vapor interface. Using the weighted density approach, we require the density functional to match with several observed properties of the fluid such as equation of state and surface tension. We also show that weighting functions for calculating the weighted density can be obtained from experimental data. Using these elements, we construct a spatial density functional theory of water and apply it to obtain densities and solvation energies of a hard-sphere solute with encouraging results.

17.
Zhonghua Fu Chan Ke Za Zhi ; 29(11): 660-1, 698-9, 1994 Nov.
Article in Chinese | MEDLINE | ID: mdl-7712886

ABSTRACT

The quantity of saturated phosphatidylcholine (SPC) in amniotic fluid was measured in 50 cases of normal late pregnancy and 21 women in labor, by improved Tsai's method. Normal values of SPC in different gestational weeks were obtained. The results showed that SPC in the amniotic fluid increased with the advancing gestational weeks and more significantly after the onset of labor. This study indicated that SPC determination can predict fetal lung maturity with high specificity, sensitivity and accuracy.


Subject(s)
Amniotic Fluid/chemistry , Lung/embryology , Phosphatidylcholines/analysis , Pregnancy/metabolism , Adult , Female , Fetal Organ Maturity , Humans , Labor Onset , Pregnancy Trimester, Third
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