[The relationship between serum lipids, apolipoproteins level and bile lipids level, chemical type of stone]

To pick up serum high risk lithogenic factors predisposing one to gallstone formation and protective factors against gallstone formation in gallbladder. We compared serum lipid and apolipoprotein level of patients with gallbladder stone (stone group) with that of patients without gallbladder stone (control group). The correlation between serum lipid, apolipoprotein level and bile lipid level, cholesterol saturated index (CSI), characteristics of lipidemia in different kinds of gallbladder stones were studied. The results showed that the increase of serum Apo A1, C2 and E level in the stone group was more significant than in the control group. But there was no statistical significance in TC, TG, LDL-C, HDL-C, Apo A2, B, C3 level between the stone and control groups. These results suggested that serum apolipoproteins perhaps are more sensitive parameters than serum lipids in distinguishing patients with stones from those without stones. There were different profiles of serum lipid and apolipoproteins in different chemical types of gallbladder stones. Increased level in serum LDL-C, Apo B and ratio of LDL-C/HDL-C were characterized by an index for cholesterol stone, otherwise that in serum TG and Apo C2 an index for pigment stones. There was a positive correlation between serum total cholesterol (TC) or Apo B, C2, C3 and cholesterol amount or CSI in gallbladder bile. Therefore, TC, Apo B, C2, C3 could be considered as high risk lithogenic factors. A positive correlation existed between serum HDL-C and lecithin in gallbladder or common bile duct (CBD) bile as well as between HDL-C and bile acids in CBD bile. Thus, HDL-C might be a protective factor against gallstone formation in gallbladder.

All-optical bistability in doped-polymer film waveguides

All-optical bistability was observed in thin-film waveguides made with acceptor-donor substituted azobenzene-doped poly(methyl methacrylate) polymer. Input-output curves with hysteresis characteristics were measured. The origin of the bistability was attributed to nonlinear coupling between a prism and a doped-polymer waveguide. An approximately theoretical analysis was introduced. Theoretical predictions were qualitatively consistent with experimental results.

Light-induced noncentrosymmetry in acceptor-donor-substituted azobenzene solutions

Light-induced noncentrosymmetry was achieved experimentally in acceptor-donor-substituted azobenzene solutions and observed by phase-matched nondegenerate six-wave mixing. The microscopic origin of the induced noncentrosymmetry was found to be orientational hole burning, which was distinguished directly with net orientation of molecules by experimental observations. The decay time of the induced noncentrosymmetry depended on the rotational orientation time of the sample's molecule, which varied linearly with the viscosity of the solvent.

Ischemia and reperfusion reduce the endogenous basic fibroblast growth factor (bF GF) in rat skeletal muscles

Polyclonal antibodies directed against human recombinant basic fibroblast growth factor (bFGF) were used in immunohistochemical studies to localize this growth factor in normal and wounded rat skeletal muscles. bFGF immunoreactivity was found mainly in the extracellular matrix, primarily in the endomysium, including the heparin-containing basal lamina and also in the capillary basal membrane of both normal and wounded muscles, however the signal intensity was much stronger in normal muscles. After 4-hour ischemia, about 40% of skeletal muscle fibers lost their bFGF immunoreactivity. Muscles which experienced 4-hour ischemia and 24 reperfusion had only a weaker bFGF immunoreactivity. The pathological results supported the concept of destroyed cell connection and fiber necrosis in ischemia and reperfused muscles. The mechanisms involved in this reduced concentration of bFGF in wounded muscles included oxygen radical activation, inflammatory response and reduced secretion of endogenous bFGF. These results were only partially compatible with the established mitogenic role of this protein and suggested that a reduction of endogenous FGF may partly contribute to a delay in wound healing.

Enzyme inhibitors: new and known polybrominated phenols and diphenyl ethers from four Indo-Pacific Dysidea sponges

Extracts and pure compounds isolated from four samples of Dysidea sp. sponges collected from two geographically distinct regions of the Indo-Pacific (Chuuk Atoll and Fiji) were assayed against five different enzyme assays, four of which are relevant to anticancer drug discovery and one of which (15-lipoxygenase) may detect compounds significant in modulating the development of atherosclerotic plaque. The pure compounds that inhibited various enzymes were polybrominated phenols and polybrominated phenoxyphenols. Fourteen of these phenols were isolated, six of which were new compounds. A variety of the phenols inhibited inosine monophosphate dehydrogenase (IMPDH), guanosine monophosphate synthetase, and 15-lipoxygenase. No activity was observed with protein tyrosine kinase pp60v-src or matrix metalloprotease.

Structural requirements of peptide and MHC for DR(alpha, beta 1*0401)-restricted T cell antigen recognition

We identified functionally important regions of the DR(alpha, beta 1*0401) peptide binding site and present a model of bound peptide. DR(alpha, beta 1*0401)-restricted T cell recognition and peptide binding of Mycobacterium leprae (ML) peptide 38-50 and overlapping peptides from the 18-kDa heat-shock protein were analyzed. ML38-50 is unusual in its restricted binding pattern, binding to only one of five DR4 subtypes and no other DR molecules tested. Amino acid substitutions were introduced into ML38-50 and the DR(alpha, beta 1*0401) peptide binding site at positions likely to influence peptide-MHC or peptide- or MHC-TCR interactions. Peptide binding, T cell proliferation, and computer modeling studies suggest that residues 39F, 42E, and 44D of ML38-50 interact with pockets 1, 4, and 6, respectively, of the peptide binding site. Only DR(alpha, beta 1*0401) substitutions at residues in pockets 4 or 7 prevented binding of ML38-50, while multiple substitutions at other positions negatively affected its T cell recognition. In contrast, T cell recognition of some high affinity ML peptides that overlapped ML38-50, and contained N-terminal extensions, was only abolished with pocket 4 substitutions. An inverse correlation of peptide affinity for DR(alpha, beta 1*0401) with negative effects of MHC substitutions on T cell recognition of the overlapping ML peptides was observed. Thus, some regions, such as pocket 4, dominantly influence T cell recognition of multiple DR(alpha, beta 1*0401)-binding peptides. However, each DR(alpha, beta 1*0401)-binding peptide appears to have unique properties that determine the outcome of its MHC-peptide interactions and the relative importance of other polymorphic pockets.

Structural requirements of peptide and MHC for DR(alpha, beta 1*0401)-restricted T cell antigen recognition

We identified functionally important regions of the DR(alpha, beta 1*0401) peptide binding site and present a model of bound peptide. DR(alpha, beta 1*0401)-restricted T cell recognition and peptide binding of Mycobacterium leprae (ML) peptide 38-50 and overlapping peptides from the 18-kDa heat-shock protein were analyzed. ML38-50 is unusual in its restricted binding pattern, binding to only one of five DR4 subtypes and no other DR molecules tested. Amino acid substitutions were introduced into ML38-50 and the DR(alpha, beta 1*0401) peptide binding site at positions likely to influence peptide-MHC or peptide- or MHC-TCR interactions. Peptide binding, T cell proliferation, and computer modeling studies suggest that residues 39F, 42E, and 44D of ML38-50 interact with pockets 1, 4, and 6, respectively, of the peptide binding site. Only DR(alpha, beta 1*0401) substitutions at residues in pockets 4 or 7 prevented binding of ML38-50, while multiple substitutions at other positions negatively affected its T cell recognition. In contrast, T cell recognition of some high affinity ML peptides that overlapped ML38-50, and contained N-terminal extensions, was only abolished with pocket 4 substitutions. An inverse correlation of peptide affinity for DR(alpha, beta 1*0401) with negative effects of MHC substitutions on T cell recognition of the overlapping ML peptides was observed. Thus, some regions, such as pocket 4, dominantly influence T cell recognition of multiple DR(alpha, beta 1*0401)-binding peptides. However, each DR(alpha, beta 1*0401)-binding peptide appears to have unique properties that determine the outcome of its MHC-peptide interactions and the relative importance of other polymorphic pockets.

Low-power phase conjugation in push-pull azobenzene compounds

Push-pull azobenzene compounds were synthesized by the diazocoupling reaction, and low-power phase conjugation of azobenzene-compound-doped poly(methyl methacrylate) films was studied with a He-Ne laser at 632.8 nm. It is shown that this kind of polymer has appreciable third-order optical nonlinearity, with a chi((3)) of approximately 10(-4) esu in the tail of absorption.

[Whole organ subserial section examination of occult breast carcinoma]

In mastectomy specimens, the primary foci of occult breast carcinoma were examinated usually by routine histopathological method, but the result was not satisfactory. The detecting rates of primary foci were 50%-56% in China and 45%-75% in some other countries. In this study, whole organ subserial section was performed in 20 cases of occult breast cancer from April, 1988 to February, 1994. Primary foci were found in 16 cases (80%) by microscopic examination. Diameters of 10 foci were less than 1.0cm and the smallest one was 0.3 x 0.1 x 0.1cm. In addition, occult breast cancer with multiple foci was detected in 5 cases (31.25%), which would be very difficult to be found by routine histopathological examination. The possible causes for the failure of detection of the primary foci on whole organ section are discussed.

[Determination of andrographolide in medicinal preparations by HPLC]

A HPLC procedure has been developed to determine andrographolide in Fencishui. The sample was analyzed on a YWG-C18 column, with methanol-water (38:62) as the mobile phase, and detected at 225nm. The average recovery was 98.42% and RSD 1.69%.

[Systemic and local administration of interferon-gamma impairs wound healing]

Interferon-gamma (IFN-gamma), which is a member of cytokine family, has many physiological functions. In this study, we evaluated the effects of IFN-gamma on wound healing in a model of incised wound of rat skin. Twenty Wistar rats were divided into three groups, consisting of IFN-gamma local administration (n = 8), IFN-gamma systemic administration (n = 8) and normal saline control (n = 4). IFN-gamma was administered in doses of 2,000 u/rat, and then daily. Wound areas were measured everyday. At day 10, tissue from wounds was obtained, and it was evaluated for protein amount in granulation tissue and also subjected to morphometric analysis with hemotoxylin and eosin and collagen fibril stain. We found that IFN-gamma impaired wound healing after either systemic or local administration as compared with control, as evidenced by reduction of new collagen fibril deposition and delay of reepidermidalization. On days 7 and 10 after wounding, wound area in normal saline treated rats was much smaller than those in rats treated with IFN-gamma. These results indicated that the impairing effects of IFN-gamma on wound healing must be considered when it is used in clinic.

Acidic fibroblast growth factor reduces rat skeletal muscle damage caused by ischemia and reperfusion

Acute interruption of arterial blood flow to the extremities is often associated with significant morbidity and mortality. Broad-spectrum mitogenic and non-mitogenic activities of FGFs inspired us to study its protecting effects on tissue injuries in ischemia reperfusion condition. We found that systemic administration of aFGF after reperfusion onset prevented severe skeletal muscle injuries. In rats treated with aFGF, the tissue edema was reduced significantly, the tissue viability was increased, and the muscle fibers contained more succinate dehydrogenase (SDH) and adenosine triphosphatase (ATPase). The pathological results supported the concept of improved prevention with aFGF treatment. The possible tissue protection by aFGF may come from its ability to regulate the concentration of extra- and intracellular calcium ion. Besides, it may moderate other Ca2+ dependent enzyme conversion processes. Also, it may take part in the vascular tone regulation under ischemia and reperfusion conditions. These results suggest further study of tissue ischemia prevention with FGF and its possible mechanisms in the future.

A new cytotoxic dihydroxy sterol from the soft coral Alcyonium patagonicum

A new sterol, 24-methylenecholest-4-ene-3 beta,6 beta-diol [1] was isolated from the soft coral Alcyonium patagonicum collected from the South China Sea. Its structure was determined by spectral analysis. Compound 1 was cytotoxic against the P-388 cell line with an IC50 value of 1 microgram/ml.

Inhibitors of protein tyrosine kinase pp60v-src: sterol sulfates from the brittle star Ophiarachna incrassata

Bioactivity-guided fractionation of the extracts of the green brittle star Ophiarachna incrassata using a protein tyrosine kinase pp60v-src inhibition assay led to the isolation of a new sterol sulfate [2] together with four known ones (1,3-5). All five compounds were found to inhibit protein tyrosine kinase pp 60v-src.

Stellettin A, a new triterpenoid pigment from the marine sponge Stelletta tenuis

A new isomalabaricane triterpenoid, stellettin A [1], was isolated from the sponge Stelletta tenuis collected off Hainan Island, People's Republic of China. Its structure and stereochemistry were established by analysis of its spectral data and reference to related compounds.

Matrix metalloproteinase inhibitor BB-94 (batimastat) inhibits human colon tumor growth and spread in a patient-like orthotopic model in nude mice

Matrix metalloproteinases have been implicated in the growth and spread of metastatic tumors. This role was investigated in an orthotopic transplant model of human colon cancer in nude mice using the matrix metalloproteinase inhibitor BB-94 (batimastat). Fragments of human colon carcinoma (1-1.5 mm) were surgically implanted orthotopically on the colon in 40 athymic nu/nu mice. Administration of BB-94 or vehicle (phosphate buffered saline, pH 7.4, containing 0.01% Tween 80) commenced 7 days after tumor implantation (20 animals/group). Animals received 30 mg/kg BB-94 i.p. once daily for the first 60 days and then 3 times weekly. Treatment with BB-94 caused a reduction in the median weight of the primary tumor from 293 mg in the control group to 144 mg in the BB-94 treated group (P < 0.001). BB-94 treatment also reduced the incidence of local and regional invasion, from 12 of 18 mice in the control group (67%) to 7 of 20 mice in the treated group (35%). Six mice in the control group were also found to have metastases in the liver, lung, peritoneum, abdominal wall, or local lymph nodes. Only two mice in the BB-94 group had evidence of metastatic disease, in both cases confined to the abdominal wall. The reduction in tumor progression observed in the BB-94-treated group translated into an improvement in the survival of this group, from a median survival time of 110 days in the control group to a median survival time of 140 days in the treated group (P < 0.01). Treatment with BB-94 was not associated with any obvious toxic effect, and these results suggest that such agents may be effective as adjunctive cancer therapies.

Interaction of sex steroids and oxytocin on term human myometrial contractile activity in vitro

OBJECTIVE

To investigate the interactions of progesterone, estradiol (E2), and oxytocin in regulating the contractile activity of term human myometrium in vitro.

METHODS

Myometrial tissues from 12 term pregnant women were obtained from the lower uterine segment at elective cesarean and immediately immersed in Hepes buffer with and without progesterone and progesterone plus E2. Oxytocin was freshly dissolved in solutions when the superfusion was started. Muscle biopsies were dissected along the bundles of smooth muscle under a stereomicroscope, and the preparations were mounted in six tissue baths superfused with different hormonal solutions. The isometric tension was recorded during the experimental time.

RESULTS

During the 2-hour contraction period, increased frequency (P < .01 for each) and decreased activity area (P < .01 for each) and duration of contractions (P < .01 for each) resulted from superfusion of muscle strips with progesterone plus oxytocin, progesterone plus E2, and a combination of progesterone, E2, and oxytocin, compared to that found with buffer alone. The higher concentration of progesterone (5 micrograms/mL) plus oxytocin and progesterone plus E2 elevated the tonus (P < .05 and P < .01), whereas progesterone in combination with E2 and oxytocin decreased it (P < .05). The lower concentration of progesterone (0.5 microgram/mL) plus E2, or both in conjunction with oxytocin, had no significant effect on tonus as compared with buffer.

CONCLUSION

The results suggest that progesterone and E2 have a direct effect on uterine excitability and a regulating influence on the oxytocin sensitivity of term human myometrium.

Immunohistochemical localization of basic fibroblast growth factor in choroid plexus of the rat

In the present study, we report that an intense bFGF-immunoreactivity has been detected in the choroid plexus of the brain ventricles of adult rats. These results suggest that epithelial choroid plexus cells may be the source of the cerebrospinal fluid bFGF.

Nitrergic innervation of rat brain vasculature

Nitric oxide synthase has been located in the brain, in several neuronal populations which appear in close contact either with the microvasculature or the external surface of extracerebral vessels. These data provide structural support to the pharmacological evidences of the nitric oxide participation in the regulation of vascular tone of brain blood vessels.

Optimal flow rates for retrograde warm cardioplegia

Retrograde delivery of warm blood cardioplegia may improve nutrient cardioplegic flow beyond coronary obstructions, but may not adequately perfuse the right ventricle and the posterior left ventricle. To determine the optimal flow rate for warm retrograde cardioplegia, we assessed 62 patients undergoing elective coronary artery bypass in two studies. In the low flow study, administration of 50 ml/min (n = 9), 75 ml/min (n = 11), or 100 ml/min (n = 7) was associated with high lactate production and oxygen extraction during cardioplegic administration. At 50 minutes of cardioplegic arrest, the coronary venous effluent pH was low in all groups. In the high flow study, 30 patients all received flow rates of 100, 200, and 300 ml/min in randomized order during the crossclamp period. In addition, five patients received cardioplegia at a rate of 500 ml/min for the duration of the crossclamp period. Administration of 200 ml/min or higher minimized lactate production and maintained coronary venous pH within the physiologic range, but flows of 300 ml/min or higher did not increase oxygen use or reduce lactate or acid production. Patients in the low flow groups had significantly greater myocardial lactate release during cardioplegic infusion and after removal of the crossclamp than the high flow group. Warm retrograde cardioplegia should be delivered at flow rates of at least 200 ml/min during elective coronary artery bypass operations.

Antitachyphylactic effects of progesterone and oxytocin on term human myometrial contractile activity in vitro

OBJECTIVE

To determine whether progesterone causes any changes in the action of oxytocin on the contractile activity of term human myometrium in vitro.

METHODS

Myometrial biopsies from 13 term pregnant women undergoing cesarean delivery were immediately immersed in Hepes buffer or buffer containing 5 micrograms/mL progesterone. In the laboratory under a stereomicroscope, the specimens were dissected into 1 x 7.5-mm muscle strips. These were mounted into six tissue baths and superfused with Hepes buffer and buffer containing 5 micrograms/mL progesterone, 5 micrograms/mL progesterone plus 10 microU/mL oxytocin, 5 micrograms/mL progesterone plus 100 microU/mL oxytocin, 10 microU/mL oxytocin, and 100 microU/mL oxytocin. Isometric tension was recorded constantly for at least 3 hours.

RESULTS

The frequency of myometrial contractions and tonus increased by superfusion with progesterone, progesterone plus oxytocin, and oxytocin alone compared to buffer. In addition, a gradual decrease in frequency was observed after 60 minutes of contractions with oxytocin alone, whereas progesterone plus oxytocin had no such decrease. The activity area of contractions was greater with 10 microU/mL oxytocin and decreased with progesterone, progesterone plus both concentrations of oxytocin, and 100 microU/mL oxytocin alone, compared to buffer.

CONCLUSIONS

Progesterone stimulated the frequency of contractions and tonus of strips from the lower uterine segment of term human myometrium. A lasting increase in the frequency of contractions was observed with superfusion of progesterone plus oxytocin, suggesting that progesterone counteracted the reaction of tachyphylaxis to oxytocin.

Low-power and broadband optical bistability by excitation of surface plasmons in doped polymer film

The low-power and broadband optical bistability in an acceptor-donor-substituted azobenzene-doped polymethyl methacrylate thin film, which relies on the excitation of surface plasmons with a cw laser of several tens of milliwatt power, is studied experimentally and theoretically. The observations on the characteristics of the bistability are essentially consistent with the theoretical predictions.

A metastatic orthotopic-transplant nude-mouse model of human patient breast cancer

We report here the development of an orthotopic-transplant model of human patient breast cancer in nude mice. Histologically-intact patient breast tumor tissue was transplanted as intact tissue to the mammary fat pad of nude mice where the tumor tissue grew extensively and metastasized to the lung. This is the first orthotopic-transplant metastatic model of human breast cancer. The potential clinical and basic-science uses of the model are discussed.

Flavonone and chalcone derivatives from Cryptocarya kurzii

Four complex flavanones, kurziflavolactones A [2], B [3], C [4], and D [5] and a complex chalcone 6 with an unprecedented carbon side chain on the flavanone or chalcone A ring have been isolated from a Malaysian plant, Cryptocarya kurzii (Lauraceae). Their structures were determined by extensive spectroscopic analysis, especially 2D nmr experiments. Compounds 3 and 6 showed slight cytotoxicity against KB cells, with IC50 values of 4 and 15 micrograms/ml, respectively. A biosynthetic pathway for the formation of these compounds is suggested.

Unexpected stimulatory effect of progesterone on human myometrial contractile activity in vitro

OBJECTIVE

To investigate the effects of continuous exposure of progesterone on contractile activity of term human myometrium in vitro.

METHODS

Myometrial biopsy specimens were obtained from 14 term pregnant women undergoing elective cesarean. The specimens were immediately immersed in Hepes buffer and buffer containing 0.33, 4.1, and 70 micrograms/mL progesterone. Muscle biopsies were dissected along the bundles of smooth muscle under stereomicroscope. These myometrial strips were mounted in tissue baths and superfused with Hepes buffer and buffer containing different concentrations of progesterone.

RESULTS

The progesterone concentration of 0.33 microgram/mL had no significant effect on myometrial contractile activity. The concentrations of 4.1 and 70 micrograms/mL increased the frequency of contractions (P < .01 for each) and tonus (P < .01 for each), decreased the activity area of contractions (P < .01 for each), and delayed the onset of contractions (P < .01 and P < .05, respectively).

CONCLUSION

When the myometrium is not deprived of progesterone, this hormone may have excitatory effects on the frequency of contractions and tonus of the lower uterine segment of term human myometrium.