Basic fibroblast growth factor reduces the gut and liver morphologic and functional injuries after ischemia and reperfusion

OBJECTIVE

To explore the possible effects of basic fibroblast growth factor (bFGF) on ischemic gut and liver injuries after trauma.

METHODS

Animal models of superior mesenteric artery occlusion (45 minutes) and reperfusion (3 days) were used in this study. Seventy-two Wistar rats were divided into three groups of 24 rats each. The animals in bFGF-treated group were injected with 4 microg bFGF/rat in 0.15 mL normal saline solution containing heparin 0.1% (w/v) through the jugular vein at the onset of reperfusion. In the normal saline control group, all rats received the same vehicle, but without bFGF. Group 3 (sham-operated) underwent the same laparotomy procedure, but without superior mesenteric artery occlusion. Liver function parameters, the levels of serum tumor necrosis factor alpha, nitric oxide, superoxide dismutase, malondialdehyde (MDA), tissue bacterial examination, and pathologic study were used to evaluate the results.

RESULTS

In bFGF-treated rats, the amounts of serum alanine transaminase and aspartate aminotransferase and serum tumor necrosis factor-alpha were reduced significantly at 6, 24, and 48 hours when compared with normal saline-treated rats. However, the changes in nitric oxide, superoxide dismutase, and MDA varied from each other as a function of time after injury. The amounts of nitric oxide were increased significantly at 6 hours in intestine in normal saline-treated rats and in liver in bFGF-treated rats (p < 0.05). At 6 hours after reperfusion, the activity of superoxide dismutase in normal saline-treated rats were much lower in liver than those in bFGF-treated and sham-operated rats (p < 0.05), but the levels of MDA were increased in intestine in bFGF-treated rats and in liver in normal saline-treated rats when compared with sham-operated rats (p < 0.05). At 24 hours, the levels of MDA in normal saline-treated rats were much higher than those in both bFGF and sham-operated rats (p < 0.05). Bacterial examination revealed that the ratio and the amounts of bacterial translocation from gut to liver, spleen, and mesenteric lymph nodes in bFGF-treated rats were much lower than those in normal saline-treated rats. The results of pathologic study support the assumption that bFGF provided protective effects against reperfusion injury.

CONCLUSIONS

Intravenous administration of bFGF may benefit in reducing gut and liver injuries after ischemia and reperfusion. The mechanisms of those effects may involve mitogenic and nonmitogenic effects of bFGF.

Gallstones and their chemical types in relation to serum lipids and apolipoprotein levels

OBJECTIVE

To determine the profile of lipidemia in patients with gallstones and the characteristics of lipidemia in different kinds of gallstone in gallbladder for predicting high risk subjects predisposed to gallstone formation by means of some serum parameters.

METHODS

Serum lipids and apolipoproteins levels in 47 patients with stone in gallbladder (stone group) were compared with those in 19 inpatients without stone (control group). The characteristics of lipidemia in different kinds of gallbladder stones were also compared.

RESULTS

Serum apolipoprotein (Apo) A1, C2 and E levels in the stone group significantly increased as compared with the control group (P < 0.01), but there were no statistically significant differences in TC, TG, LDL-C, HDL-C, HDL-C/TC, LDL-C/HDL-C, Apo A2, B and C3 and Apo A1/Apo B levels between the stone and control groups (P > 0.05). Increased levels of serum LDL-C and Apo B and the LDL-C/HDL-C ratio (P < 0.05) were characterized as an index of cholesterol stones, while elevated levels of serum TG and Apo C2 (P < 0.05) as an index of pigment stones.

CONCLUSIONS

Serum apolipoproteins might be more sensitive parameters as compared with serum lipids in distinguishing patients with stones from subjects without stones. There are different profiles of serum lipids and apolipoproteins in different chemical types of gallbladder stones.

[Surface photovoltaic spectroscopic investigation of Bacteriorhodopsin (BR)]

The surface photovoltaic spectra (SPS) of Bacteriorhodopsin-based films were systematically measured. The results show that the BR films are characterized by the specific photovoltaic effect. The SPS response of the BR films depends on the fabrication and humidity of the film. The intermediate M412 and O640 of BR are observed in the SPS of HEPES-containing BR film, indicating that HEPES has very important function to stabilize intermediate M412. The observations are explained in terms of the photocycle of BR and the mechanism of photovoltage generation.

E2a-Pbx1 induces aberrant expression of tissue-specific and developmentally regulated genes when expressed in NIH 3T3 fibroblasts

The E2a-Pbx1 oncoprotein contains the transactivation domain of E2a joined to the DNA-binding homeodomain (HD) of Pbx1. In mice, E2a-Pbx1 transforms T lymphoblasts and fibroblasts and blocks myeloblast differentiation. Pbx1 and E2a-Pbx1 bind DNA as heterodimers with other HD proteins whose expression is tissue specific. While the transactivation domain of E2a is required for all forms of transformation, DNA binding by the Pbx1 HD is essential for blocking myeloblast differentiation but dispensable for fibroblast or T-lymphoblast transformation. These properties suggest (i) that E2a-Pbx1 causes cellular transformation by activating gene transcription, (ii) that transcription of E2a-Pbx1 target genes is normally regulated by ubiquitous Pbx proteins and tissue-specific partners, and (iii) that DNA-binding mutants of E2a-Pbx1 activate a subset of all gene targets. To test these predictions, genes induced in NIH 3T3 fibroblasts by E2a-Pbx1 were identified and examined for tissue- and stage-specific expression and their differential abilities to be upregulated by E2a-Pbx1 in NIH 3T3 fibroblasts and myeloblasts and by a DNA-binding mutant of E2a-Pbx1 in NIH 3T3 cells. Of 12 RNAs induced by E2a-Pbx1, 4 encoded known proteins (a J-C region of the immunoglobulin kappa light chain, natriuretic peptide receptor C, mitochondrial fumarase, and the 3',5'-cyclic nucleotide phosphodiesterase, PDE1A) and 5 encoded new proteins related to angiogenin, ion channels, villin, epidermal growth factor repeat proteins, and the human 2.19 gene product. Expression of many of these genes was tissue specific or developmentally regulated, and most were not expressed in fibroblasts, indicating that E2a-Pbx1 can induce ectopic expression of genes associated with lineage-specific differentiation.

[Uterine activity in active phase]

This study was designed to understand the uterine activity (UA) in normal labor. 43 nulliparous women(33 in normal course of labor and 10 in abnormal course of labor) were in the active phase of spontaneous labor with cephalic presentation for vaginal delivery. An open-end fluid filled intrauterine catheter connected to a pressure transducer was used to measure the uterine contraction intensity, frequency and duration. UA was quantified by means of Montevideo Unit (MU) and Uterine activity integral(UAI). The receiver operator characteristic(ROC) curve defined the cut-off points of UA between normal labor and abnormal labor. The results showed that MU and UAI were correlated with the rate of cervial dilatation in the active phase of labor (r = 0.3734 and 0.3502 respectively, P < 0.05). There was a strong correlation between MU and UAI (r = 0.7173, P < 0.001). The mean of UA in normal labor as MU = 226(s = 68.45) mmHg/15 min. UAI = 901(s = 258.02) kPa/15 min. The minimum of UA to normal labor in MU was 170 mmHg/15 min, of UAI 650 kPa/15 min. The study suggests that quantification of UA is very useful in the management of labor, especially in the proper use of oxytocin in cases abnormal labor.

[The characteristic infrared spectra of alpha,alpha'- dioxoketene cyclic dithioacetals]

In this paper, based on the results of previous paper[1], the other characteristic infrared spectra of alpha,alpha'- dioxoketene cyclic dithioacetals have been studied and their changing rules with the change of chemical structure have been indicated.

Percutaneous transluminal coronary angioplasty for acute myocardial infarction: initial experience in 43 cases

OBJECTIVE

To evaluate the initial experience with the use of percutaneous transluminal coronary angioplasty (PTCA) in the set of acute myocardial infarction (AMI).

METHODS

Between October 1993 and April 1996, PTCA was performed in 43 patients (34 male, 9 female) with initial onset of AMI. These patients ranged in age from 40 to 74 years (mean +/- SD, 60.3 3 +/- 9.2). Primary PTCA was performed in 16, rescue PTCA in 8, and semi-elective PTCA in 19 patients.

RESULTS

The initial success was achieved in 95.3% (41/ 43). Failed angioplasty occurred in 2 patients, with acute reocclusion after rescue PTCA (this patient died of cerebral stroke 3 days later) in one patient, and small local intimal dissection during semi-elective PTCA in another patient.

CONCLUSION

PTCA was a safe and effective approach in the treatment of AMI in the present study patients, with a high primary success and low acute complication rate.

New brominated diphenyl ether from an unidentified species of Dysidea sponge. 13C NMR data for some brominated diphenyl ethers

The structure of a new brominated diphenyl ether, 1, isolated from an unidentified species of Dysidea sponge, has been solved by spectroscopic analysis. 13C NMR data of related diphenyl ethers were also assigned by analysis of their HMQC and HMBC spectra.

Makaluvic acids A and B: novel alkaloids from the marine sponge Zyzzya fuliginosus

Two new substituted pyrrolecarboxylic acids, makaluvic acids A (5) and B (6), were isolated from the sponge Zyzzya fuliginosus, which was collected in Chuuk Atoll, Federated States of Micronesia. The known alkaloids 3,7-dimethylisoguanine (1) and makaluvamines A (2), E (3), and K (4) were also isolated.

Ocular symptoms of tumors at sella turcica region

BACKGROUND

The sella tumors were found in 15% of intracranial tumors. The sella turcica region locates in the base of skull, so the carcinoma patients in early stage often showed no intracranial hypertension and other positive signs of neural system. However, the patients presented visual field defect and hypopsia, and often went to see the doctor of ophthalmology, which resulted from that the tumor often compressed optic nerve and chiasm. We analysed the symptomatic changes of the visual organs in order to provide a diagnostic basis for sellar tumor in ophthalmological department.

CLINICAL MATERIALS

Of the 407 cases of sellar tumors, 296 were pituitary adenoma, 52 were craniopharyngioma, 43 were meningioma, and the rest 16 were other kinds of sellar tumors. We analysed their ocular changes of the sellar tumors and the characteristics of the tumors.

RESULTS

The sellar tumor in its early stage is mainly symptomized as visual field changes. Visual field defect was found in 92.9% of pituitary adnoma, 75% of craniopharyngioma and 34.8% meningioma patients. The patients of intermediate and later sellar tumors gradually manifested the hypopsia and optic atrophy. Hypopsia was found in 86.5% of pituitary adenoma patients, 89.9% of craniopharyngioma and 48.8% of meningioma patients. The morbidity rate of optic atrophy is 59.5% in patients with pituitary adenoma, 65.5% of craniopharyngioma and 44.1% of meningioma.

CONCLUSION

The misdiagnostic rate of sellar tumor in ophthalmological department still keeps comparatively high. The reason is that: (1) The doctors lack the neuroophthalmological knowledge. (2) The patients were not examined attentively enough. The ocular symptoms of sellar tumors are often the first occurred and most important changes. In the clinical practice, all the patients showing visual acuity and visual field disturbances should be examined carefully (especially in visual field) and excluded ocular diseases, should be transferred to the department of neurosurgery for further diagnosis and treatment.

Effects of progesterone and oxytocin on intracellular elemental composition of term human myometrium in vitro

OBJECTIVE

To study the effects of progesterone and oxytocin on contractile activity related to the intracellular elemental composition of human pregnant myometrium.

STUDY DESIGN

Myometrial strips were mounted in tissue baths and superfused with plain buffer, oxytocin or progesterone. Progesterone was initially added to the tissue bath or at the onset of spontaneous contraction of the strips. The myometrial contractile activities were recorded isometrically and the results were analyzed by a specific computer program. The effects of oxytocin and progesterone on the intracellular elemental composition were studied by X-ray microanalysis in an electron microscope.

RESULTS

The contractile activity in terms of frequency and tonus of the muscle strips was increased by oxytocin and progesterone. This increase was more pronounced if progesterone was added to the bath at the start of the experiment. After 120 min of incubation with oxytocin and progesterone the total intracellular concentration of calcium was significantly higher (P < 0.0001 and P < 0.002, respectively) compared to buffer.

CONCLUSIONS

(i) Oxytocin increases total intracellular calcium concentration concomitant with an increase in uterine contractile activity. (ii) Progesterone increases the myometrial tone and frequency of contractions, simultaneously with an increase in total intracellular calcium.

Progesterone, oestradiol and oxytocin and their in vitro effect on maintaining the number of gap junction plaques in human myometrium at term

Previous studies by electron microscopy and laser confocal microscopy of immunohistochemically stained sections have shown that during pregnancy the extent of gap junction formation in human myometrium is low, but that an increase occurs in the active stages of labour despite a high concentration of progesterone in maternal blood. The present investigation focused on the effect of in vitro exposure of isolated myometrial tissue to progesterone, oestradiol and oxytocin, on the number of gap junction plaques in human myometrium at term. Myometrial biopsies were obtained at term from 13 pregnant women who had an elective caesarean section in the 37th or 40th week of pregnancy. The biopsies were immersed immediately in Hepes buffer and buffer containing 0.5, 5.0 micrograms mL-1 of progesterone, and 0.1 micrograms mL-1 of oestradiol. The muscle biopsies were trimmed under a stereo microscope into strips along the bundles of smooth muscle cells and mounted in tissue baths, superfused with Hepes buffer supplemented with glucose (0.01 mM); subsequently the strips were exposed to buffer containing different concentrations of progesterone, oestradiol and oxytocin. Incubation of the muscle strips for 180 min resulted in a significant decrease of the number of gap junctions (P < 0.01). Neither oestradiol or oxytocin, alone or in combination, had a significant effect on the maintenance of the number of gap junctions. The progesterone concentration of 5.0 micrograms mL-1, combined with oxytocin, and with or without oestradiol has a significantly positive effect on the number of gap junction plaques in strips of human myometrium at term (P < 0.05 vs. buffer alone). The high concentration of progesterone in the superfusion medium during in vitro experiments may be responsible for the maintenance of high numbers of gap junction complexes in term human myometrium. This finding is of interest in the light of findings of persisting high progesterone levels in maternal blood during labour.

Presence of free radicals in pigment gallstone in vivo

OBJECTIVE

To clarify whether free radical, which may play a role in pigment gallstone formation, is present in pigment gallstones in vivo.

MATERIALS AND METHODS

Free radical signal of gallstones from 18 patients was detected by electron paramagnetic resonance spectroscopy at 77K under anaerobic condition and in air (control). As soon as the anaerobic determination was finished, the fresh anaerobic sample was exposed to air and stored in a freezer at -20 degrees C.

RESULTS

Free radical signal (g = 2.0038) was detected in fresh anaerobic samples containing more than 2% bilirubin compound, and the signal intensity correlated linearly with the content of calcium bilirubinate (r = +0.95, P < 0.0005). During the storage at -20 degrees C and exposure to air, the signal intensity of each anaerobic sample and its control increased gradually, eventually reaching the same stable level. Fe(III) signal intensity was enhanced synchronously and related linearly with free radical signal (r = +0.99, P < 0.0005).

CONCLUSIONS

Free radical exists originally in pigment gallstones in vivo, and it may play an important role in pigment gallstone formation. The free radical signal carried by gallstones may be strengthened by the action of oxygen in air on bilirubin. The transition metal ions probably take part in the formation of bilirubin free radical.

Multiple organ injuries and failures caused by shock and reperfusion after gunshot wounds

Experiments were performed to observe the changes of multiple system organ failure (MSOF) and gut barrier function caused by shock and reperfusion after gunshot wounds. Eighteen dogs were divided randomly into two groups. In the experimental group, the dogs were subjected to 60 minutes of shock (40mm Hg), followed by reinfusion of shed blood after hindlimb gunshot wounds. In the control group, the dogs experienced pure gunshot wounds without shock and reperfusion. The results showed that dogs in the experimental group developed multiple system organ injuries or failures compared with the control group. The levels of malondialdehyde (MDA) values in plasma were significantly elevated in the experimental group when compared with preinjury and the control group. Gut flora disorder, bacillus intestinalis overgrowth, and bacterial translocation occurred in the experimental group. The pathological results support the gut barrier function injury. The results indicated that pure gunshot wounds do not easily injure gut barrier function and produce MSOF. Gunshot wounds with shock and reperfusion are capable of causing gut flora disorder, bacillus intestinalis overgrowth, and lead to bacterial translocation, furthermore causing MSOF. Although fluid resuscitation is a potential treatment modality, pathogenically, it can lead to MSOF.

In vivo effects of tumor necrosis factor-alpha on incised wound and gunshot wound healing

Recombinant tumor necrosis factor alpha (TNF-alpha) was applied to incised wounds (adult rats, n = 14) and gunshot wounds (dogs, n = 5). The accumulation of RNA and DNA in regenerative tissue, the wound disruption strength (WDS), and histology were examined. The results showed that a single dose of TNF-alpha in saline with highly purified bovine serum albumin increased the WDS and accumulation of RNA and DNA in regenerative tissue in incised wounds 3 days after surgery (p < 0.05). Also, TNF-alpha promoted the inflammatory reaction in the wounded area of gunshot wounds. Histology revealed increased capillary tube-like structures and collagen formation and fibroblast proliferation in both incised and gunshot wounds treated with TNF-alpha. The results indicated that locally applied TNF-alpha benefited the incised and gunshot wound healing. These mitogenic and inflammatory effects of TNF-alpha may be the synergistic effects with other growth factors such as platelet-derived growth factor (PDGF).

Effects of estradiol and interaction with progesterone or oxytocin on term human myometrial contractile activity

BACKGROUND

To investigate the effects of estradiol (E2) alone and in combination with progesterone or oxytocin on contractile activity of term human myometrium in vitro.

METHODS

Myometrial specimens were obtained from 24 term pregnant women not in labor who underwent elective cesarean. Biopsies were kept in ice-cold and oxygenated Hepes buffer and buffer containing different hormonal solutions. The biopsies were dissected and mounted in tissue baths at 37 degrees C and isometric tension was recorded.

RESULTS

(1) Estradiol at 0.1 and 1 microgram/mL increased the contractile frequency (p < 0.01 for each), decreased the tonus (p < 0.05 and p < 0.01) and suppressed the activity area of contractions (p < 0.05 and p < 0.01) as compared to control. (2) No significant differences in frequency and activity area of contractions between strips superfused with E2 plus progesterone and progesterone alone were recorded. Myometrial tonus was decreased by 0.1 microgram/mL or 1 microgram/mL E2 plus progesterone as compared to progesterone alone (p < 0.05 and p < 0.01). (3) There were no significant differences in frequency between strips superfused with E2 plus oxytocin and oxytocin alone. Myometrial tonus was decreased by 0.1 microgram/mL or 1 micrograms/mL E2 plus oxytocin as compared with oxytocin alone (p < 0.05 and p < 0.01). Estradiol at 0.1 microgram/mL or 1 micrograms/mL plus oxytocin reduced the activity area of contractions compared to oxytocin (p < 0.05 and p < 0.01).

CONCLUSIONS

These data suggest that E2 had both stimulatory and inhibitory effects on term human myometrial contractility and that E2 altered the myometrial response to progesterone and oxytocin mainly by decreasing tonus.

The ability of bile to scavenge superoxide radicals and pigment gallstone formation in guinea pigs

After partial ligation of the common bile duct (CBD) of guinea pigs, 14 of 16 animals developed pigment gallstones within one week (S group). Intraperitoneal injection of Vit. E and C, each 10 mg/kg daily from 3 days before CBD ligation to one week after the operation (S+V group), decreased the gallstone incidence to 5/14 (exact probability < 0.01). The gallstone incidence in the control group, that only received laparotomy without ligation of the CBD, was 0/15. Biochemical analysis of the gallbladder bile showed that stricture of the CBD was associated with a significant increase in levels of unconjugated bilirubin (UCB) and Ca2+ (p < 0.05 and < 0.01). Simultaneously the scavenging rate (SR) of superoxide radical in bile significantly decreased (p < 0.05). Comparing S+V group with S group, the effect of Vit. E and C on the concentrations of UCB and Ca2+ in bile was not significant (both p > 0.05), but Vit. E and C normalized the SR, and the difference between S group and S+V group was significant (p < 0.05). These results suggested that Vit. E and C, known as antioxidants, enhanced the ability to scavenge oxygen radical in S+V group; and that in addition to the increases of UCB and Ca2+ concentrations, the participation of oxygen radicals might be of importance for pigment gallstone formation induced by bile duct obstruction.

[Relationship between wound healing and TNF, MDA and SOD contents in granulation tissues of rats in the first week]

An experimental model was used to determine the changes in TNF, MDA and SOD in granulation tissues during natural wound healing after skin excision on rats. Our results indicated that the changes in TNF and SOD exhibited a curve of V. The levels of TNF and SOD were lower on day 7 than day 3. The levels of MDA rose gradually, especially on day 7. A positive correlation was shown between TNF and MDA (at days 3, 5, 7), also between TNF and SOD (at day 3, 7). When the concentration of TNF was lower than 90 Pg/mg protein, the process of wound healing was best, while wound healing was hindered when the levels of SOD were low. The results suggest that in the process of wound repair there are influential changes in the contents of TNF, MDA and SOD. Lower levels of TNF and higher levels of SOD are apparently beneficial to wound healing after trauma.

Chemical constituents of halophilic facultatively anaerobic bacteria, 1

Two new nitrotyramine derivatives, 1 and 2, along with five known aromatic compounds, were isolated from the culture broth of a facultatively anaerobic, halophilic bacterium isolated from a sediment from the Great Salt Plains, Alfalfa County, Oklahoma. The structures of the new compounds were determined from spectral data and were confirmed by synthesis from tyramine hydrochloride. Compound 1 showed cytotoxicity against the murine leukemia P-388 cell line (IC50 3 micrograms/ml).

[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.