[Effect of dietary intake on body mass index in middle aged and elderly population]

The paper investigated and analyzed the relationship between the nutrient intake and body mass index (BMI) of 200 middle-aged and elderly people(aged 35 - 74 years) in Changsha. The result showed that the constituent rate of underweight (BMI< 18.5) was 6.5% and that of over-weight (BMI<25.0) was 23.5%. The amount of fat intake constituted slightly higher proportion in energy intake. The stepwise regression analysis indicates that the body mass index increases with the increasing intake of carbohydrates.

Nuclear magnetic resonance studies of the N-terminal fragment of adenosine diphosphate ribosylation factor 1 in micelles and bicelles: influence of N-myristoylation

The N-terminal fragment of adenosine diphosphate (ADP) ribosylation factor 1 (ARF1) is proposed to be involved in the guanosine triphosphate- (GTP-) dependent, reversible association of the protein with membranes through the interaction of not only the N-linked myristoyl chain but also its highly conserved N-terminal hydrophobic residues. Based on the N-terminal sequence of this protein, specifically (13)C- and (15)N-labeled peptides were synthesized with and without an N-myristoyl anchor. The behavior, including structure, dynamics, and orientation, of these peptides in a lipid environment was then studied through a combination of solution (1)H nuclear magnetic resonance (NMR) techniques in micelles and heteronuclear solid-state NMR experiments in magnetically aligned bicelles. The work presented is an extension of the previously reported characterization of the myristoylated N-terminal fragment of ARF1 [Losonczi and Prestegard (1998) Biochemistry 37, 706-716] to include a comparison to a nonmyristoylated analogue. Results indicate that both myristoylated and nonmyristoylated peptides are alpha-helical in a lipid environment and that N-myristoylation does not greatly influence the structure of the peptides. Evidence is presented suggesting association of the peptides with bilayer disks through a combination of edge and surface interactions.

Isolation of cDNAs encoding gibbon and monkey platelet and T cell activation antigen 1 (PTA1)

Human platelet and T cell activation antigen 1 (PTA1) is a 67kDa type I transmembrane glycoprotein mainly expressed on the surface of activated T cells and platelets, and is involved in the development of human cytotoxic T cell (CTL) as well as platelet activation and aggregation. We have cloned and sequenced gibbon PTA1 (gPTA1) and monkey PTA1 (mPTA1) cDNAs by RT-PCR from gibbon leukemic cell line MLA 144 and PHA-induced Rhesus monkey PBMC respectively. The mature proteins of gPTA1, mPTA1 and human PTA1 (hPTA1) share 93-95% amino acid similarity with the highest similarity in domain 1 of extracellular region. All the important features of PTA1 molecule are conserved among these Primates: (1) the ORF encoding 336 amino acid residues including signal sequence (18aa), extracellular region (232aa), transmembrane sequence (25aa) and cytoplasmic region (61aa); (2) two conserved pairs of Cys (Cys19 to Cys90 and Cys134 to Cys204) forming disulfide bonds stabilizing the two immunoglobulin superfamily V-like domains; (3) eight putative N-linked glycosylation sites (except gPTA1 with nine sites) and three O-linked glycosylation sites in extracellular region; and (4) predicated protein kinase C phosphorylation sites (Thr275 and Ser311), casein kinase II sites (Ser295 and The299) and the potential tyrosine phosphorylation site (Tyr304). These data indicate that PTA1 molecule is highly conserved among the Primates and may play important roles in immune response.

Receptor reserve analysis of the human CCR3 receptor in eosinophils and CCR3-transfected cells

A novel pharmacological study of CCR3 receptor reserve in a CCR3-transfected cell (CREM3) and human eosinophils was done; functional responses measured were increases in intracellular calcium and chemotaxis. Eotaxin, eotaxin-2, monocyte chemoattractant protein-4 (MCP-4), RANTES, and MCP-3 induced similar maximal eosinophil chemotaxis, whereas MCP-3 and RANTES induced submaximal calcium responses in eosinophils compared to eotaxin, MCP-4, and eotaxin-2. This suggested a receptor reserve in the chemotaxis response. Receptor reserve was quantitated for eotaxin. Occupancy of all CCR3 receptors was required for a maximal calcium response in both CREM3 and eosinophils (reserve = 1.0 or 0.17, respectively); the stimulus-calcium response relationship was linear, indicating no receptor reserve. In contrast, in eosinophils a large receptor reserve (6.5) was found for chemotaxis, where occupancy of 15% receptors drove half-maximal responses. These studies indicate that CCR3 interacts with G-proteins that are poorly coupled to the calcium response, whereas coupling efficiency and/or amplification to the chemotaxis apparatus in human eosinophils is significantly greater.

[Fibronectin induces matrix metalloproteinase-2 expression in ovarian cancer cells]

OBJECTIVE

To investigate the effects of extracelluar matrix proteins on matrix metalloproteinases (MMPs) expression by cancer cells, and the underlying mechanisms.

METHODS

Following stimulation of SKOV3 ovarian cancer cells by fibronectin, MMPs secretion and cellular mRNA contents were assayed by gelatin-zymography and RT-PCR, respectively. The activity of MMP-2 promoter was monitored by cellular luciferase activity after the cells were transfected with MMP-2 promoter-luciferase construct. Cellular p53 contents were determined by Western blot analysis.

RESULTS

Fibronectin (5 micrograms/ml) was found to stimulate the secretion of MMP-2 but not MMP-9 by SKOV3 cells. The stimulation was enhanced with the increase in fibronectin concentration. When SKOV3 cells were treated with 10 micrograms/ml fibronectin for 1 hr, the cellular MMP-2 mRNA dramatically increased. However, with increase in stimulation time, MMP-2 mRNA content decreased. Fibronectin induced an increase in luciferase activity in cells transfected with MMP-2 promoter construct, whilst curcumin (50 mumol/L), a potent transcription factor AP-1 inhibitor, could not block the fibronectin-induced increase in MMP-2 promoter activity. Fibronectin also induced an increase in p53 content of SKOV3 cells.

CONCLUSION

Fibronectin stimulates ovarian cancer cells to secret MMP-2 via its enhancing effect on MMP-2 promoter activity with resultant increase in MMP-2 transcription. The effect might involve a pathway associated with p53 but independent of AP-1.

Bioactive flavonoids from the black locust tree, robinia pseudoacacia

Five flavonoids, acacetin ( 1 ), secundiflorol I ( 2 ), mucronulatol ( 3 ), isomucronulatol ( 4 ), and isovestitol ( 5 ) were isolated, with the fractionation being guided by the brine shrimp lethality test (BST), from the ethanolic extract of the whole plant of Robinia pseudoacacia (Fabaceae). The structures of 1 - 5 were identified by spectral analyses. Compounds 2 - 5 are, for the first time, reported from this species. Corrections have been made for the previous literature assignments of the 13 C NMR resonances of compounds 1 - 3 . Bioactivities in BST and cytotoxicities against a panel of six solid human tumor cell lines were determined, and 1 was significantly cytotoxic in the prostate cell line (PC-3).

[Traumatic perilymphatic fistula of round and oval windows (four cases reported)]

OBJECTIVE

To explore the diagnosis and treatment to traumatic perilymph fistula (PLF) of round and oval window.

METHOD

Traumatic PLF was diagnosed by the traumatic history of head, neck and ear, the examinations of auditory and vestibular function, and the exploratory tympanotomy. The PLF of round and oval windows were repaired by fascia graft or tragus perichondrium and gelform. Four cases with traumatic PLF of round and oval window were reported in this paper, which included 2 cases hitten by hand, 1 by brick, 1 insulted by middle ear surgery. Exploratory tympanotomy was performed from one and half to nine months after injury. One case was misdiagnosed as Meniere's disease before confirming PLF. Exploration and repair of PLF underwent in all cases.

RESULT

The symptom of vertigo relieved in all cases after surgery, while the hearing recovery was not evident.

CONCLUSION

1. Traumatic PLF is unrare, hence, traumatic PLF should be alerted if patients suffer from vertigo and hearing impairment after head and ear injury. 2. The features with vertigo attacks, fluctuating hearing loss and tinnutis should be distinguished from Meniere's disease. 3. Early exploratory tympanotomy and repair of PLF are effective for relieving vertigo and improving hearing.

Sign determination of dipolar couplings in field-oriented bicelles by variable angle sample spinning (VASS)

Residual dipolar couplings are being increasingly used as structural constraints for NMR studies of biomolecules. A problem arises when dipolar coupling contributions are larger than scalar contributions for a given spin pair, as is commonly observed in solid state NMR studies, in that signs of dipolar couplings cannot easily be determined. Here the sign ambiguities of dipolar couplings in field-oriented bicelles are resolved by variable angle sample spinning (VASS) techniques. The director behavior of field-oriented bicelles (DMPC/DHPC, DMPC/CHAPSO) in VASS is studied by 31P NMR. A stable configuration occurs when the spinning angle is smaller than the magic angle, 54.7 degrees, and the director (or bicelle normal) of the disks is mainly distributed in a plane perpendicular to the rotation axis. Since the dipolar couplings depend on how the bicelles are oriented with respect to the magnetic field, it is shown that the dipolar interaction can be scaled to the same order as the J-coupling by moving the spinning axis from 0 degree toward 54.7 degrees. Thus the relative sign of dipolar and scalar couplings can be determined.

The assignment of chemokine-chemokine receptor pairs: TARC and MIP-1 beta are not ligands for human CC-chemokine receptor 8

Identification of chemokine receptors and their associated ligands is crucial to the understanding of most immune reactions. Three human chemokines [I-309, thymus and activation-regulated chemokine (TARC) and macrophage inflammatory protein-1beta (MIP-1beta)] have been reported to be ligands for CC-chemokine receptor 8 (CCR8). In this report, we present evidence that TARC and MIP-1beta did not bind to or induce chemotaxis through CCR8 on a stable transfected cell line (1D-21) and did not bind to CCR8 on in vitro differentiated human CD4(+) Th(2) cell cultures. Also, I-309-dependent calcium mobilization in 1D-21 cells and in Th(2) cells was desensitized by I-309 but not by MIP-1beta or TARC. These results provide strong evidence that, at physiologically relevant concentrations, I-309 is the only known human ligand for CCR8. These data also provide a framework for suggesting minimum requirements for the assignment of chemokine receptor-ligand pairs.

Correlations of structure, dynamics and function in the gramicidin channel by solid-state NMR spectroscopy

The high resolution structure of the gramicidin A channel has been determined in a lamellar phase environment using solid-state NMR spectroscopy. While the fold is similar to previous characterizations, channel function is exquisitely dependent on structural detail. There is essentially no structural change upon cation binding and no significant change in dynamics. The cations appear to be adequately solvated in their binding site by no more than two carbonyls and no fewer than three water molecules at any one time. The relatively large number of water molecules allows for geometric flexibility and little selectivity among monovalent cations. However, the dehydration energies of cations clearly explain the selectivity for monovalent versus divalent cations. Moreover, the binding site is shown to be delocalized, resulting in a shallow potential energy well so that efficient cation conductance can be realized. The potential energy barrier at the bilayer centre has been shown to be rate limiting under certain circumstances through a correlation between conductance and the electrostatic interactions between cations at the gramicidin monomer-monomer junction and the indole dipole moments at the lipid-water interface. The dynamics are functionally important. The time-scale for carbonyl fluctuations about the C alpha-C alpha axis and kinetic rates for cation movement in the channel are the same, suggesting a correlation between molecular dynamics and kinetics. These functional correlations will be described in light of the recent K+ channel structure and the biological challenge to achieve both selectivity and efficiency.

13C selective polarization and spin diffusion in a lipid bilayer-bound polypeptide by solid-state NMR

While (15)N solid-state NMR has proven to be very advantageous for the development of structural biological methods, (13)C spectroscopy has increased sensitivity and spectral dispersion. However, large natural abundance signals and homonuclear dipolar interactions pose significant problems. Here we have used a pair of (13)C-labeled sites in a lipid-solubilized polypeptide to show the selective polarization can be used in combination with spin diffusion to achieve simplified spectra. Both unoriented and oriented samples have been used, with the latter providing a well-resolved homonuclear dipolar splitting.

Cyclic GMP-dependent protein kinase-I in the guinea pig cochlea

Recent studies have begun to characterize the nitric oxide/cyclic GMP/protein kinase G pathway in the mammalian cochlea by demonstrating the presence of both the enzyme that produces nitric oxide (NO), nitric oxide synthase, and the NO receptor, soluble guanylate cyclase. The present study investigated protein kinase G (cyclic GMP-dependent protein kinase-I, cGK-I), the downstream enzyme of this pathway that frequently mediates its physiological effects. A commercial antibody to a human cGK-I sequence recognized a protein of appropriate molecular weight in Western blots of guinea pig aorta. Immunostaining of guinea pig aorta was consistent with the expected distribution of cGK-I. In lateral wall tissues of the cochlea, pericytes lining the blood vessels of the spiral ligament were strongly immunoreactive. In the organ of Corti, cGK-I was detected in Hensen's, Deiters', and pillar cells, but not in inner and outer hair cells. This distribution coincides with the localization of soluble guanylate cyclase activity and suggests that cGK-I mediates the effects of the NO/cyclic GMP pathway in the cochlea. It reinforces the hypothesis that the NO/cyclic GMP/cGK-I pathway is involved in regulation of cochlear blood flow and supporting cell physiology.

Cation transport: an example of structural based selectivity

Through the high-resolution structure of the gramicidin A channel in lamellar phase lipids and the characterization of specific ion peptide interactions, fundamental principles for ion channel selectivity and conductance efficiency are illustrated with atomic resolution detail. Delocalized cation binding in the first turn of the helix reduces the unfavorable entropy contribution upon binding. Stepwise dehydration minimizes the energy barrier for cation entry and provides valence selectivity in this channel. Three or more water molecules in the monovalent cation binding site result in flexibility in the cation solvation environment causing weak cation size selectivity. Lack of cation induced structural modification avoids the formation of a significant energy barrier, thus permitting efficient cation transport.

Cation binding induced changes in 15N CSA in a membrane-bound polypeptide

Cation binding to the monovalent cation selective channel, gramicidin A, is shown to induce changes in the dipolar and chemical shift observables from uniformly aligned samples. While these changes could be the result of structural or dynamic changes, they are shown to be primarily induced by through-bond polarizability effects when cations are solvated by the carbonyl oxygens of the peptide backbone. Upon cation binding partial charges are changed throughout the peptide plane, inducing large changes in the 13C1 chemical shifts, smaller changes in the 15N chemical shifts, and even smaller effects for the 15N-13C1 and 15N-2H dipolar interactions. These conclusions are substantiated by characterizing the 15N chemical shift tensors in the presence and absence of cations in fast-frozen lipid bilayer preparations of gramicidin A.

[NiTi shape-memory alloy cramp used in repair of skull defect]

Fixation of silicon-polyester fiber network on skull defect was usually difficult to handle and the fixation was unstable. In order to solve these problems, NiTi shape-memory alloy cramp was adopted and 101 patients with skull defects were selected for this clinical trial. Among them, there were 79 males and 22 females, and the age ranged from 12-55 years old. The area of skull defect ranged from 3 cm x 4 cm to 10 cm x 16 cm. All of these patients received repairing of the skull defects by silicon-polyester fiber network which was fixed by NiTi memory alloy cramps. After operation, there was no complication. One hundred patients were followed up for 1-8 years, in which 97 cases returned to their normal work, and only 2 cases had a transient dysfunction of frontal muscle for 2 months. In addition, There were no loosening of the cramps, displacement of plastic network and malignant degeneration. The NiTi shape-memory alloy cramps had the following advantages: 1. Simple operative procedure; 2. Rigid fixation; 3. Mild postoperative tissue reaction; 4. Few postoperative complication; 5. Favorable effect of skull repair; 6. No interference with CT and MRI image; 7. No carcinogenicity.

[Nontypical limited resection of the lung]

OBJECTIVE

To evaluate the role of limited resection in the treatment of lung disease.

METHOD

From 1989 to 1996, 46 limited resections were performed on 35 patients with lung diseases. All patients were followed up for 0.5 to 7 years (mean 29.3 months).

RESULT

There were no operative deaths and operative complications. In 16 patients with benign lung diseases, no recurrences and late complications were found. In 5 patients with primary lung cancers, 2 died 1.5 and 2 years after operation, respectively, and 3 are still living well for 2.5, 4 and 5 years postoperatively. In 14 patients with metastatic lung diseases (10 with bilateral multiple metastases), 216 metastatic lesions were excised. 1-, 3-, and 5-year survival rates were 78.5%, 50% and 21.4% respectively.

CONCLUSION

Limited lung resection could be an additional option and a surgical alternative to conventional lung resection for some compromised patients.

[Determination of the soluble non-starch polysaccharides in rice and wheat bran by gas chromatography]

Cereal polysaccharides can be broadly classified into two distinct and chemically well-defined types. They are the storage polysaccharides (alpha-glucan) and the structural polysaccharides starch (beta-glucan) which are usually called non-starch polysaccharides (NSP). The determination of soluble non-starch polysaccharides in rice and wheat bran by gas chromatography has been developed. The free sugars in the sample were extracted with 80% ethanol. The residue was hydrolyzed in an acetic acid buffer solution (pH 5.0) in the presence of amylase and amyloglucosidase to remove starch. The soluble NSP obtained was further hydrolyzed in the acidic condition to produce the corresponding monosaccharides which were derivatized to form alditol acetates for GC analysis with allose as the internal standard. The GC conditions were OV-1701 column (25 m x 0.3 mm) with temperature program from 195 degrees C to 225 degrees C and FID.

[Hepaticocholangiochole cystostomy plus construction of subcutaneous tunnel of the gallbladder in the treatment of hepatolithiasis with bile duct stricture]

A novel operation was designed by using Hartmann's pouch of the gallbladder to anastomose stone-strictured intrahepatic bile duct while leaving the common bile duct and Oddis sphincter intact and fixing the fundus of the bladder subcutaneously. 28 patients with intrahepatic bile duct stones and strictures underwent the operation successfully, and recovered well. There were no postoperative complications such as reflux cholangitis or disturbances of GI tract.