[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.

Nude mouse metastatic models of human stomach cancer constructed using orthotopic implantation of histologically intact tissue

Nude mice have been used to develop s.c. growing human stomach tumors, but these rarely metastasize. Recently, I. J. Fidler and others have developed orthotopic implantation metastatic models using cell suspensions which are inoculated into the corresponding organ of nude mice from which the tumor cells were originally derived in the human. However, recent work has indicated that disaggregated cell suspensions may not always express their full metastatic potential. In this light, we have recently developed an orthotopic implant model utilizing intact tissue such as that obtained directly from surgery. This approach has yielded high take rates and frequent metastases in colon cancer, bladder cancer, lung cancer, pancreatic cancer, and prostate cancer. We report here the application of this intact tissue orthotopic implant technique to stomach cancer resulting in the formation of metastases in 100% of the mice with extensive primary growth to the regional lymph nodes, liver, and lung. In contrast, when cell suspensions were used to inject stomach cancer cells at the same site, metastases occurred in only 6.7% of the mice with local tumor formation, emphasizing the importance of using intact tissue to allow full expression of metastatic potential. Injuring the serosa similar to that occurring in intact tissue transplantation did not increase the metastatic rate after orthotopic injection of cell suspensions of stomach tumor cells. This intact tissue orthotopic implantation model should allow development of new treatment modalities and further study of the biology of human stomach cancer.

Human ovarian carcinoma metastatic models constructed in nude mice by orthotopic transplantation of histologically-intact patient specimens

We report here the first orthotopic transplant model for human ovarian cancer. Histologically-intact patient specimens of ovarian cancer were transplanted by microsurgical techniques under the capsule of the nude mouse ovary. The human tumors grew locally and gave rise to a patient-like metastatic pattern including the parietal peritoneum, colon, omentum, and ascites. The orthotopic model described here should be useful for evaluating new therapeutics and diagnostics for ovarian cancer.

A new patient-like metastatic model of human small-cell lung cancer constructed orthotopically with intact tissue via thoracotomy in nude mice

A new nude-mouse metastasizing orthotopic transplant model of human small-cell carcinoma of the lung is described. Histologically-intact human small-cell lung tumors were transplanted to the left lung of nude mice via a thoracotomy procedure we have developed. The transplanted tumors grew extensively locally and metastasized to the opposite lung, lymph nodes and other clinically-relevant sites. The results described indicate the model developed could have clinical relevance and contrasts with models of small-cell carcinoma constructed with injections of cell suspensions which result in few or no metastases.

Extensive liver metastasis from human colon cancer in nude and scid mice after orthotopic onplantation of histologically-intact human colon carcinoma tissue

Clinically-relevant animal models of human cancer are greatly needed for the study of human cancer biology and the development of new cancer therapeutics and diagnostics. We report here that by orthotopically transplanting histologically-intact human colon cancer to the colon of the immunodeficient nude and scid mouse mutants that extensive local growth and liver metastases occur consistently even after extensive in vivo orthotopic passage. We demonstrate that the liver metastases arise by hematogenous spread. The models described in this report for human colon cancer should prove useful for individual cancer patients as well as for basic and applied studies to develop improved treatment.

A patient-like metastasizing model of human lung adenocarcinoma constructed via thoracotomy in nude mice

A new nude-mouse metastasizing orthotopic transplant model of human adenocarcinoma of the lung is described. Histologically-intact human A549 adenocarcinoma lung tumors were transplanted to the left lung of nude mice via a thoracotomy procedure we have developed. The transplanted tumors grew extensively locally and metastasized to the opposite lung, lymph nodes and other clinically-relevant sites. The results described indicate the model developed could have clinical relevance and contrast with models of the A549 lung adenocarcinoma constructed orthotopically with injections of cell suspensions which result in low metastatic potential.

A metastatic nude-mouse model of human pancreatic cancer constructed orthotopically with histologically intact patient specimens

Pancreatic cancer is one of the most intractable and least understood of all human cancers. Pancreatic cancers is the fourth-leading cause of cancer-related mortality in the United States with less than 2% of the patients surviving for 5 yr. In an effort to help develop more effective treatment modalities for pancreatic cancer and improve detection, we report an animal model for individual human pancreatic-cancer patients. The model involves orthotopic transplantation of histologically intact pancreatic-cancer specimens to the nude-mouse pancreas, which can result in models that resemble the clinical picture including (i) extensive local tumor growth, (ii) extension of the locally growing human pancreatic cancer to the nude-mouse stomach and duodenum, (iii) metastases of the human pancreatic tumor to the nude-mouse liver and regional lymph nodes, and (iv) distant metastases of the human pancreatic tumor to the nude-mouse adrenal gland, diaphragm, and mediastinal lymph nodes. In a series of five patient cases, a 100% take rate has been demonstrated, and of 17 mice transplanted, 15 supported tumor growth. Immunohistochemical analysis of the antigenic phenotype of the transplanted human pancreatic tumors showed a similar pattern of expression of two different human tumor-associated antigens, such as tumor-associated glycoprotein 72 and carcinoembryonic antigen in the transplanted tumors when compared with the original surgical biopsy, suggesting similarity between the two. This model should, therefore, prove valuable for treatment evaluation of individual cancer patients, as well as for evaluation of experimental treatment modalities for this disease.