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The propagating characteristics of the water and muddy waves are one of the concerns of theoretical studies because of the following facts: (1) With the development of the economy in the estuaries, local residents and government paid increasing attention to the ecological environment of the estuarine beaches The propagating characteristics of the water and muddy waves are closely related to the ecological environment, the concern of the government and the residents. (2) The propagating characteristics of the mud are the bottleneck of the study of the coastal and beach dynamics because of the complicated constitutive relation of the mud. The different constitutive models may lead to different explanations of its mechanism. Hence, the proper selection of the model is one of the keys to reveal the true kinematic properties of the mud in the estuaries. This paper first establishes a power law model of the constitutive relation of the mud. Based on this model, a gravity wave theory is proposed. According to the mechanism of the mud wave transportation, the coupled mud-water wave field can be divided into two layers. The upper layer is described as the viscous Newtonian fluid, whereas the lower high-concentration mud layer is described as the power law fluid. Next, the equations of the proposed model are discretized and the calculations are made by using the difference method. Then, the propagating characteristics are discussed, and the dispersion relations of the water and mud waves are analyzed in detail.

Invasive prolactinomas are more likely to be resistant to drug therapy but the mechanism of this is still unknown. The objective of this study was to analyze the different expression of ERmRNA and D2RmRNA isoforms in prolactinomas responsive and resistant to dopamine agonist (DA), and to discuss the correlation of such gene expression with tumor biological behavior. A prospective study of 20 consecutive patients who harbored prolactinomas was designed. Patients were classified as responsive (14 cases) or resistant (six cases) according to their clinical and biochemical response to bromocriptine. Tumor tissue samples were examined by means of QRT-PCR analysis. Median D2SmRNA expression in responsive patients was about 2.5-fold that in resistant ones (13.5 +/- 10.4 and 5.4 +/- 2.4, respectively, P = 0.09). No significant difference was found between D2LmRNA expression levels (P = 0.77). However, there was a significant difference between D2S/D2LmRNA ratios for responsive and resistant tumors (P = 0.012). A significant difference was not found between these two groups in levels of ERalphamRNA and ERbetamRNA expression (P = 0.20 and 0.06, respectively). D2SmRNA expression was significantly different for invasive and noninvasive tumors (6.2 +/- 3.6 vs. 17.0 +/- 11.2, respectively, P = 0.02). The D2S/D2L ratio is related to the responsiveness of prolactinomas to DA medication, in which D2SmRNA plays an important role. Lower expression of D2SmRNA in invasive tumor patients suggests that invasive prolactinomas may be more likely to be resistant to DA medication.

Object The aim of this study was to observe long-term clinical outcomes in a group of patients treated with bromocriptine for invasive giant prolactinomas involving the cavernous sinus. Methods Data from 20 patients with invasive giant prolactinomas at the authors’ institutions between July 1997 and June 2004 were retrospectively reviewed. The criteria to qualify for study participation included: 1) tumor diameter greater than 4 cm, invading the cavernous sinus to an extent corresponding to Grade III or IV in the classification scheme of Knosp and colleagues; 2) serum prolactin (PRL) level greater than 200 ng/ml; and 3) clinical signs of hyperprolactinemia and mass effect. Among the 20 patients who met the criteria, six had undergone unsuccessful transcranial or transsphenoidal microsurgery prior to bromocriptine treatment and 14 patients received bromocriptine as the primary treatment. Eleven of the 20 patients underwent adjuvant radiotherapy. After a mean follow-up period of 37.3 months, the clinical symptoms in all patients improved by different degrees. Tumor volume on magnetic resonance images was decreased by a mean of 93.3%. In 11 patients, the tumor had almost completely disappeared; in the other nine patients, residual tumor invaded the cavernous sinus. Visual symptoms improved in 13 of the patients who had presented with visual loss. Eight patients had normal PRL levels. The postoperative PRL level was more than 200 ng/ml in seven patients. During the course of drug administration, cerebrospinal fluid leakage occurred in one patient, who subsequently underwent transsphenoidal surgery. No case of apoplexy occurred during bromocriptine treatment. Conclusions Dopamine agonist medications are effective as a first-line therapy for invasive giant prolactinomas, because they can significantly shrink tumor volume and control the PRL level. Tumor mass vanishes in some patients after bromocriptine treatment; in other patients with localized residual tumor, stereotactic radiosurgery is a viable option so that unnecessary surgery can be avoided. The application of radiotherapy does not reliably shrink tumor volume.

To explore the inhibitory effect of non-functioning pituitary adenoma (NFPA) cells after a combined treatment of adenovirus mediated D2S gene and bromocriptine in vitro.Adenovirus containing dopamine 2 receptor short isoform (D2S) gene was used to infect NFPA cells. The transfection of D2S gene into NFPA cells was confirmed by immunofluorescence. And cell apoptosis of infected cells treated by bromocriptine was evaluated with CCK-8 assay in vitro.When D2S gene transfection and bromocriptine was used in combination, the survival rate of NFPA cells significantly decreased (40 ± 5)% versus the control group (97 ± 5)% and the pAd-EGFP transfection combined bromocriptine treatment group (90 ± 9)% (P0.05).The combined treatment of adenovirus-mediated D2S gene and bromocriptine can effectively induce the apoptosis of NFPA cells on primary culture and increase the sensitivity of NFPA to dopamine agonist.

To observe the postoperative residual non-functioning pituitary adenomas (PR-NFPAs) without postoperative radiotherapy and to analyze the natural history of PR-NFPAs' growth in order to provide a basis for selecting appropriate strategies of clinical treatment.We evaluated the natural history of 20 patients with PR-NFPAs who did not receive postoperative radiotherapy and drug therapy. Through MRI images, the residual tumor volumes of those patients were serially measured. We further calculated the monthly growth rate and the tumor volume doubling time (TVDT) and analyzed the correlations between the patient age, gender, volume of residual tumor, cavernous sinus (CS) invasion and TVDT.All patients received observation alone. Among which, 17 adenomas increased in volume and 3 remained unchanged during a follow-up period of 7 months to 17 years (mean 3.90 yr). The mean patient age was 41.8 years. As to 17 patients with tumor regrowth, the tumor volume at the beginning of MRI observation period was 4.73 cm(3) and tumor volume at the last MRI observation was 16.98 cm(3). During the mean 4-year follow-up period, the average monthly growth rate of PR-NFPAs was 7.87% and the mean TVDT was 724 days. Such factors as patient age, gender, volume of residual tumor and CS invasion did not affect the TVDT of PR-NFPAs.The tumor growth rate of PR-NFPAs is not significantly correlated with the patient gender, age, volume of residual tumor and CS invasion. In conjunctions with the volume of PR-NFPAs and the distance between residual adenoma and optic chiasm, we should take the TVDT into consideration and determine the appropriate and safe follow-up period.

Background Few data are presently available on the effective control of cavernous sinus (CS) invasion of invasive prolactinomas. The aim of this retrospective study, through a mean period of 5 years follow up, is to observe the tumor shrinkage of CS invasive prolactinomas, as well as PRL normalization with bromocriptine therapy. Methods 68 patients met the criteria of invasive prolactinomas (Grade III or IV in the classification scheme of Knosp and colleagues; serum PRL level greater than 200 ng/ml). 33 patients underwent bromocriptine therapy as the initial treatment, and 14 of these 33 had combined treatment with microsurgery and/or radiotherapy. The other 35 patients received microsurgery as the primary treatment, after which two patients had normal PRL without taking bromocriptine and other 33 patients received bromocriptine treatment after microsurgery. Results Tumor volume on magnetic resonance images had completely disappeared in 50 patients (74%), while all the other 18 patients had residual tumor in the parasellar areas, invading the CS, and 14 patients had a secondary empty sella due to tumor shrinkage. Of those 14 patients, seven still had elevated PRL levels; five had optic chiasmal herniation by different degrees (P < 0.05). There were 49 patients with normal PRL levels (72%); five patients with PRL levels more than 200 ng/ml. After the treatment, 14 patients with tumor volume disappearance on MR images and PRL normalization therefore withdrew from bromocriptine therapy. During a subsequent one-and-a-half-year follow-up, tumor recurrence and PRL increase were not found in those 14 patients. Twenty-seven patients maintained normal PRL levels with low-dose bromocriptine, of which 20 patients had their tumor disappear while seven patients had CS residual tumor. Conclusions About three-fourths of prolactinomas with CS invasion can be effectively controlled not only with regard to tumor volume disappearance but also in serum PRL normalization. Residual tumor in the CS areas with PRL normalization and no pressure symptoms can be treated with low-dose of bromocriptine so as to achieve long-term tumor volume control and endocrine control. Great attention should be paid to CS residual tumors accompanying the empty sella, especially in cases with optic chiasmal herniation.