Menopause is associated with lumbar disc degeneration: a review of 4230 intervertebral discs.

OBJECTIVE: The main objective of this study was to investigate, in a population of normal postmenopausal women, the association between menopause and severity of lumbar disc degeneration from the first lumbar to the first sacral vertebra on magnetic resonance imaging. METHODS: Between January 2010 and May 2013, 846 normal women and 4230 intervertebral discs were retrospectively analyzed. Age, height, weight and years since menopause (YSM) were recorded. Disc degeneration was evaluated using the modified Pfirrmann grading system. RESULTS: Compared to premenopausal and perimenopausal women, postmenopausal women had more severe disc degeneration after removal of age, height and weight effects (p < 0.0001). Postmenopausal women were divided into six subgroups for every 5 YSM. When YSM was below 15 years, there was a significant difference between every two groups, i.e. groups 1-5 YSM, 6-10 YSM and 11-15 YSM (p < 0.01). A positive trend was observed between YSM and severity of disc degeneration, respectively, i.e. L1/L2 (r = 0.235), L2/L3 (r = 0.161), L3/L4 (r = 0.173), L4/L5 (r = 0.146), L5/S1 (r = 0.137) and all lumbar discs (r = 0.259) (p < 0.05 or 0.01). However, when YSM was above 15, there was no difference, i.e. groups 16-20 YSM, 21-25 YSM and 26-30 YSM (p > 0.05), and the significance correlation also disappeared (p > 0.05). CONCLUSION: Menopause is associated with disc degeneration in the lumbar spine. The association almost entirely occurred in the first 15 years since menopause, suggesting estrogen decrease may be a risk factor for lumbar disc degeneration.

[Clinical features and advanced progress of secondary BPPV].

BPPV is a disease provoked by abrupt head movements, results in short paroxysmal vertigo or nystagmus. These patients often can accurately describe the dizziness happened when they head move suddenly, especially when looking upward, turning over in bed, lying down, or bending over. BPPV is divided into idiopathic BPPV and secondary BPPV, in most cases. The underlying cause cannot be determined, which is called idiopathic; however, in 30% patients, BPPV may be attributed to a specific cause and is termed secondary BPPV. We reviewed the pathogenesis, mechanisms, clinical features, treatment and the latest progress of secondary BPPV.

Effect of VEGF on neuronal degeneration and interaction between Alzheimer's disease biomarkers.

The article "Effect of VEGF on neuronal degeneration and interaction between Alzheimer's disease biomarkers" by H.-C. Yuan, C.-W. Jiang, L.-Y. Hou, Y.-B. Lv, X.-Z. Feng, L.-F. Guo, G. Sun, K. Liu, Y.-J. Liu, B. Xu, C.-Y. Wang, published in Eur Rev Med Pharmacol Sci 2017; 21 (16): 3649-3657 has been withdrawn.

Conformational transition in DNA on a cold surface.

The contour length of DNA fragments, deposited and imaged on mica under buffer, was measured as a function of deposition temperature. Extended DNA molecules (on Ni- and silane-treated surfaces) contract rapidly with falling temperature, approaching the contour length of A-DNA at 2 degrees C. The contraction is not unique to a specific sequence and does not occur in solution at 2 degrees C or on a surface at 25 degrees C, indicating that it arises from a combination of low temperature and surface contact. It is probably a consequence of reduced water activity at a cold surface.

Conformation and rigidity of DNA microcircles containing waf1 response element for p53 regulatory protein.

The tumor-suppressor activity of p53 is closely related to its DNA-binding properties. It binds a number of DNA response-elements and it is likely that these share a common structural feature. Here, we present a new, general method to determine the absolute twist of flexible DNA promoter sequences based on direct imaging of the topology of microcircles containing the sequences. We have used magnetically driven dynamic force microscopy ("MacMode" AFM) to observe, in solution, the conformation of 168 base-pair DNA microcircles, each containing four equally spaced copies of the waf1/cip1/p21 p53 response-element. Analysis of the images showed that the microcircles are markedly puckered with a small excess of negatively writhed molecules. The average measured values of writhe are 0.109+/-0.013 (for 60 positively writhed molecules) and -0.098+/-0.011 (for 65 negatively writhed molecules). These values lead directly to a difference in linking number for the positively and negatively writhed molecules prior to ligation, from which we derive a twist mismatch of 178 degrees (overtwist). This is 44.5 degrees for each 42-mer precursor containing a single waf1/cip1/p21 p53 response-element, in good agreement with the range of values deduced by indirect biochemical techniques. The two values of writhe may also be used to determine the ratio of the bending (B) to twisting (C) rigidity, yielding B/C=0.23. This is about one-third of the value for long, random-sequence DNA, suggesting that the waf1/cip1/p21 p53 response-element is extremely flexible, a result that is also consistent with indirect biochemical experiments. These results support the idea, proposed by us earlier, that torsional stress may play a role in the regulation of p53 binding through modulation of twist at the binding site.

Differential mercury volatilization by tobacco organs expressing a modified bacterial merA gene.

Mercury pollution is a major environmental problem accompanying industrial activities. Most of the mercury released ends up and retained in the soil as complexes of the toxic ionic mercury (Hg2+), which then can be converted by microbes into the even more toxic methylmercury which tends to bioaccumulate. Mercury detoxification of the soil can also occur by microbes converting the ionic mercury into the least toxic metallic mercury (Hg0) form, which then evaporates. The remediation potential of transgenic plants carrying the MerA gene from E. coli encoding mercuric ion reductase could be evaluated. A modified version of the gene, optimized for plant codon preferences (merApe9, Rugh et al. 1996), was introduced into tobacco by Agrobacterium-mediated leaf disk transformation. Transgenic seeds were resistant to HgCl2 at 50 microM, and some of them (10-20% ) could germinate on media containing as much as 350 microM HgCl2, while the control plants were fully inhibited or died on 50 microM HgCl2. The rate of elemental mercury evolution from Hg2+ (added as HgCl2) was 5-8 times higher for transgenic plants than the control. Mercury volatilization by isolated organs standardized for fresh weight was higher (up to 5 times) in the roots than in shoots or the leaves. The data suggest that it is the root system of the transgenic plants that volatilizes most of the reduced mercury (Hg0). It also suggests that much of the mercury need not enter the vascular system to be transported to the leaves for volatilization. Transgenic plants with the merApe9 gene may be used to mercury detoxification for environmental improvement in mercury-contaminated regions more efficiently than it had been predicted based on data on volatilization of whole plants via the upper parts only (Rugh et al. 1996).

Investigation of the interaction between acridine orange and bovine serum albumin.

The results from the measurement of the fluorescence spectrum showing the binding characteristics of acridine orange (AO) and bovine serum albumin (BSA) are reported. It was found that the equilibrium constant k=4848.64 l mol(-1), and the number of binding sites n=0.82. Based on the mechanism of the Forster energy transference, the transfer efficiency of energy and distance between the acceptor AO and BSA were found. The interaction between AO and BSA have been verified as consistent with the static quenching procedure and the quenching mechanism is related to the energy transfer.

Feigrisolides A, B, C and D, new lactones with antibacterial activities from Streptomyces griseus.

Four new lactone compounds, named feigrisolides A to D (1 to 4), have been isolated from Streptomyces griseus. The chemical structures were determined by detail analysis of their spectroscopic data and chemical transformations. Structurally, the feigrisolides A (1) and B (2) are hepta-lactones, feigrisolide C (3) and D (4) are 16-membered macrodiolides. Biological studies showed that feigrisolide B (2) exhibited strong antibacterial, as well as medium cyctotoxic, and antiviral activities. Feigrisolides A (1), C (3) and D (4) are medium inhibitors of 3alpha-hydroxysteroid-dehydrogenase (3alpha-HSD) inhibiting activity.

New 1-O-acyl alpha-L-rhamnopyranosides and rhamnosylated lactones from Streptomyces sp., inhibitors of 3 alpha-hydroxysteroid-dehydrogenase (3alpha-HSD).

Chemical screening with extracts of Streptomyces sp. (strain GT 61150) resulted in the detection, isolation, and structure elucidation of two new acyl alpha-L-rhamnopyranosides (1 and 2) and three new rhamnosyllactones A, B1 and B2 (3 approximately 5). Rhamnosyllactones B1 and B2 were obtained as a 5:1 mixture. The structures were confirmed by spectroscopic analysis, especially 2D-NMR techniques. The rhamnosyltransferase of our strain is able to connect the sugar moiety to heteroaromatic carboxylic acids and enols. The metabolites 1 and 4/5 as well as previously reported acylrhamnosides 6 approximately 11 inhibit the enzyme 3alpha-hydroxysteroid-dehydrogenase (3alpha-HSD).

Aerosol lead and associated elements in Beijing, China.

The relative importance of local and regional sources of lead and associated elements in fine and coarse aerosol particles of an urban atmosphere was assessed by means of a two-day study, July 20 and 30, 1980 in Beijing, China. Five near-ground locations were selected for aerosol sampling by cascade impactors and elemental analysis by proton induced X-ray emission (PIXE): the imperial palace courtyard, a park, near two streets, and a mid-street traffic island. These sites, ranked in order of increasing traffic intensity and fugitive surface dust, showed that concentrations of major dust constitutents, represented by coarse particle (>2 µm diameter) Si, Al, and Ca, increased correspondingly. Pb, as well as Zn, As, and Cu, were present mainly in fine (<2 µm) particles; their concentrations were unrelated to traffic, indicating they resulted mainly from regional combustion or other sources. However, these elements also were present in coarse particles at concentrations that varied with the major dust elements and were relatively enriched, compared to average earth crust rock material, by factors of more than 100 (Pb), 50 (Zn), and 10 (Cu). Nonurban Beijing shows much smaller coarse aerosol enrichments of Pb, Zn, and Cu, indicating urban contamination of surface dust. Published data from St. Louis, USA show both fine and coarse aerosol Pb and Zn. Compared with Beijing, fine and coarse concentrations in St. Louis are similar for Pb, but lower for Zn, Ca, and Fe. Both Pb and Zn are enriched relative to earth crust composition to a greater degree in St. Louis than Beijing in both fine and coarse particle size ranges. The results suggest that heavy metals from combustion occur in the air as fine particles and, after deposition on the surface, as reentrained coarse particles of fugitive dust. Both many contribute to human exposures of these heavy metals.

A new triterpenoidal saponin from Ixeris sonchifolia and its cytotoxic activity.

A new triterpenoidal saponin, echinocystic acid 3-O-beta-D-glucopyranosyl-(1-->3)-alpha-L-arabinopyranoside (1), was isolated from Ixeris sonchifolia. Its structure was elucidated on the basis of full spectral data analysis and chemical methods. The cytotoxic activity of compound 1 was evaluated using the tumor cell lines of A375, Hela, and L929 in vitro.

Steroidal saponins from Dioscorea panthaica and their cytotoxic activity.

A new steroidal saponin, dioscoreside E (1), and a known compound, protodioscin (2), were isolated from an ethanol extract of the rhizomes of Dioscorea panthaica. The structure of 1 was established as 3-O-[bis-alpha-L-rhamnopyranosyl-(1 --> 2 and 1 --> 4)-beta-D-glucopyranosyl]-26-O-beta-D-glucopyranosyl-20(R)-methoxy-25(R)-furosta-5,22(23)-diene-3beta,26-diol, on the basis of spectral and chemical evidence. Compounds 1 and 2 showed cytotoxic activity against a panel of tumor cell lines.

[New oxindole alkaloid glycosides from Uncaria sinensis].

Two 16-carboxy derivatives of pentacyclic oxindole alkaloids and its glucopyranosyl esters have been isolated from the ethanolic extract of the leaves of Uncaria sinensis (Olive.) Havil. These structures were deduced on the basis of spectroscopic evidences and chemical correlations, and named mitraphyllic acid (I), isomitraphyllic acid (II), isomitraphyllic acid (16-1)-beta-D-glucopyranosyl ester (III) and mitraphyllic acid (16-1)-beta-D-glucopyranosyl ester (IV).

[Chemical investigation of genus Hedyotis. II. Isolation and identification of iridoids from Hedyotis chrysotricha].

Many species of genus Hedyotis (Rubiaceae) were used as folk medicine for treatment of cold, inflammation, cancer and etc. in China. The alcoholic extract of the whole plant of H. chrysotricha showed good hepatoprotective effects. From the alcoholic extract ten iridoids were isolated and their structures were elucidated as: asperuloside (1), scandoside methyl ester (2), asperulosidic acid (3), deacetyl asperulosidic acid (4), loganin (5), deacetyl asperuloside (6), acetyl scandoside methyl ester (7), 6 beta-hydroxy-genipin (8) and two new compounds named hedyoside (9) and 6'-acetylasperuloside (10), by means of chemical and spectral methods.

[Studies on the chemical constituents of Armillaria mellea mycelium. V. Isolation and characterization of armillarilin and armillarinin].

Two new protoilludane sesquiterpenoid aromatic esters, armillarilin C24H30O7, mp 179-180 degrees C, [alpha]D14 + 162 (c 0.97 CHC1(3] and armillarinin C24H29O7 C1, mp 152-155 degrees C, [alpha]D17 + 153.6, (c 0.09, CHC1(3], have been isolated from the artifically cultured mycelium of Armillaria mellea (Vahl. ex Fr.) Quel (Tricholometaceae). On the basis of spectral (UV, IR, 1HNMR, 13CNMR and MS) analysis their structures were identified as I and II, respectively.

[Chemical constituents of Armillaria mellea mycelium. VII. Isolation and characterization of chemical constituents of the acetone extract].

Eight compounds were isolated from the acetone extract of artificially cultured mycelium of Armillaria mellea (Vahl. ex Fr.)Quel.(Tricholomataceae). Three of them are protoilludane sesquiterpenoid aromatic esters. Their structures were elucidated by spectral data analysis as the known 4'-methylmelledonal (I)and two new compounds named armillaritin (II) and armillarivin (III). In addition, five known compounds were identified as D-erythritol, D-mannitol, azelaic acid, orsellinic acid and glycerin-alpha-monooleate.

[Chemical constituents of Armillaria mellea mycelium. VI. Isolation and structure of armillaripin].

A new protoilludane sesquiterpenoid aromatic ester, named armillaripin, C24H30O6, mp 202-204 degrees C, [alpha]D15 + 130 degrees (c 0.055, CHCl3), was isolated from the petroleum ether extract of the artificially cultured mycelium of Armillaria mellea (Vahl. ex Fr.) Quel. (Tricolometaceae) by silica gel chromatography. On the basis of spectral (UV, IR, 1HNMR 13CNMR and MS) analysis its structure was deduced as I and confirmed by single-crystal X-ray analysis.

New guaianolides from Artemisia selengensis.

A new guaianolide artselenin (1) and a new dimeric guaianolide artselenoid (2), along with 10 known compounds, were isolated from the aerial parts of Artemisia selengensis. Their structures were elucidated by spectroscopic methods. Two-dimensional NMR techniques were used to make complete assignments for the 1H- and 13C-NMR chemical shifts of the two new guaianolides.

A new sesquiterpene lactone glucoside from Ixeris sonchifolia.

A new sesquiterpene lactone glucoside, Ixerin Z1 (1), was isolated from the whole plants of Ixeris sonchifolia (Bge.) Hance, along with 15 known compounds. The structure of 1 was elucidated as 1(10),3,11(13)-guaiatriene-12,6-olide-2-one-3-O-[6'-(p-hydroxyphenylacetyl)]-glucopyranoside by spectroscopic methods including 2D-NMR techniques.