Biomedical subjects

Zongguang Zhou

Publications and source records attributed to Zongguang Zhou.

10 recordsLinked to original sources

PubMed2005

Patterns of neoplastic foci and lymph node micrometastasis within the mesorectum.

BACKGROUND AND AIMS: Local recurrence after rectal cancer surgery is conceived to result from microscopically incomplete resection. We aimed to investigate the patterns of mesorectal neoplastic foci, and examined the involvement and micrometastasis of lymph nodes. METHODS: Observation of large tissue slice and analysis of tissue microarray were integrated in the pathological study of 31 total mesorectal excision (TME) specimens. RESULTS: Altogether, 349 mesorectal neoplastic foci were examined from 18 specimens. Almost 33% of them were in the outer layer of mesorectum. Concerning position of primary tumor, ipsilateral neoplastic foci were significantly more than contralateral neoplastic foci. Distal mesorectal spread was found in four patients with the distance ranging from 1 to 3.5 cm. Four specimens were diagnosed to have circumferential margin involved. Nine hundred seventy-two lymph nodes were harvested with 128 involved by tumor. No significant difference in occurrence of micrometastasis was observed among tumors of different stage. CONCLUSIONS: Combination of large tissue slice and tissue microarray provided a more detailed method in studying the metastasis of rectal cancer. Complete excision of the mesorectum with fascia propria circumferentially intact is essential. Circumferential margin involvement and micrometastasis suggested that tumor spread may go beyond the scope of a single TME procedure.

Adenocarcinoma↗

PubMed2005

[Expression of human papillomavirus 16 E7 DNA in patients with colorectal adenocarcinoma].

The relationship between Human papillomavirus (HPV) 16 infection and the natural course of colorectal adenocarcinoma has not been fully defined. In this study, the HPV 16 E7 DNA was detected in 82 patients with primary colorectal adenocarcinoma to study the relationship between HPV 16 infection and colorectal carcinoma. Samples were taken from both the tumors and the adjacent normal mucosa in the same patient. Polymerase chain reaction (PCR) was used to amplify the HPV16 E7 DNA fragment. The PCR products were gel-purified and sequenced for HPV genotyping. DNA sequence analysis indicated that PCR product was 297 bp. It was the equivalent of 562-858th pairs in the HPV 16 primitive sequences. Our results showed HPV16 E7 DNA expression was significantly higher in colorectal carcinoma (42/82) than in adjacent normal mucosa (4/82). The correlation was found between HPV16 E7 expression and tumor's location; the positive rate was 18.18% in the ascending colon carcinoma group and 64.10% in the rectal carcinoma group. High HPV16 E7 expression was also associated with lower Dukes stage (P < 0.01). These results indicated that there was correlation between colorectal adenocarcinoma and HPV 16 infection. HPV16 infection was relatively higher in the colorectal carcinoma and rare in the adjacent normal mucosa. Specimens expressing higher levels of HPV 16 E7 DNA were associated with lower Dukes stage and more distal location.

Adenocarcinoma↗

PubMed2004

Microscopic spread of low rectal cancer in regions of the mesorectum: detailed pathological assessment with whole-mount sections.

BACKGROUND AND AIMS: The aim was to investigate the regional spread of microscopic tumor nodules in the mesorectum of patients with low rectal cancer, and to provide further pathological evidence for optimal procedure selection of radical resection for rectal cancer. PATIENTS AND METHODS: Sixty-two patients with low rectal cancer underwent low anterior resection and total mesorectal excision (TME). Surgical specimens were sliced transversely on serial embedded blocks at 2.5-mm intervals, and stained with hematoxylin and eosin. On whole-mount sections the mesorectum was divided into three regions: the outer region of the mesorectum (ORM), the middle region of the mesorectum (MRM), and the inner region of the mesorectum (IRM). Microscopic metastatic foci were investigated for metastatic mesorectal region, frequency, types, involvement of the lymphatic system, and correlation with the primary tumor. RESULTS: Microscopic spread of the tumor was observed in 38.7% of patients (24 out of 62) and that in the ORM was observed in 25.8% of the patients (16 out of 62). Microscopic tumor foci spread in the circumferential resection margin (CRM) occurred in 6.5% of the patients (4 out of 62), and distal mesorectum (DMR) involvement was detected in 6.5% (4 out of 62), with the spread extending to within 3 cm from the lower margin of the tumor. CONCLUSIONS: The results of the present study support the theory that complete excision of the mesorectum without destruction of the ORM is essential for surgical management of low rectal cancer, and an optimal DMR clearance resection margin should be no less than 4 cm. Four patients with microscopic tumor nodule spread in the ORM observed in the study suggested that microscopic metastases exist in pelvic lateral areas and in the mesorectum simultaneously, indicating the significance of preoperative and/or postoperative radiochemotherapy.

Adenocarcinoma↗

PubMed2004

[On PACAP-aggravated experimental acute pancreatitis].

The role of PACAP (pituitary adenylate cyclase activating polypeptide), a peptidergic transmitter, in the pathogenesis of acute pancreatitis is not yet clear. This experiment was conducted to examine the action of exogenous PACAP on rat pancreas and on the course of experimental acute pancreatitis. The results showed that 5-30 microg/kg of PACAP slightly raised the serum amylase level, induced pancreatic edema (23.88% +/- 2.532%-25.86% +/- 1.974% of experiment groups versus 29.21% +/- 5.657% of control group), inflammatory cell infiltration, vacuolization of acinar cells, and occasionally fatty and parenchymal necroses. 15-30 microg/kg of PACAP aggravated cerulein-induced acute pancreatitis; the pancreatic edema became more marked (13.45% +/- 2.045%-17.66% +/- 4.652% of expreiment groups versus 21.83% +/- 3.013% of cerulein group, P<0.05), the serum amylase level became higher; and ascites, pancreatic bleeding, fatty and parenchymal necroses, and extensive vacuolization of acinar cells appeared. For sodium taurocholate-induced pancreatitis, 5-10 microg/kg of PACAP mildly attenuated the pancreatic edema, reduced the serum amylase level (1986.91 +/- 710.97-2944.33 +/- 1182.47 IU/L vs 3690.87 +/- 2277.99 IU/L, P<0.05), whereas it caused multifocal hemorrhage and prominent necrosis in pancreas. Except the cerulein-induced pancreatitis groups, other groups were found to have reduced pancreatic functional capillary density (FCD); when pancreatic edema was taken into consideration and calibrated FCD was introduced (FCD weighted against pancreatic wet/dry ratio), all groups revealed increases in pancreatic functional capillaries when compared with normal control. In conclusion, PACAP is proinflammatory in the pathogenesis of acute pancreatitis, PACAP plus cerulein can induce acute hemorrhagic/necrotizing pancreatitis, and the action of PACAP on cerulein-induced panceatitis may differ from that on sodium taurocholate-induced one. In this experiment, pancreatic FCD was underestimated due to pancreatic edema.

Amylases↗

PubMed2003

[The effects of traditional Chinese medicine on distribution of F-actin of leukocytes in acute edematous pancreatitis].

OBJECTIVE: To explore the distribution of F-actin of leukocytes in local circulation of pancreas and system circulation and assess the effects of traditional Chinese medicine WPY complex there on in the case of acute edematous pancreatitis(AEP). METHODS: AEP model of Wistar rats was induced with subcutaneous injection of cerulein. In the treatment group, rats were given 50% WPY (1.5 ml every time) at 0, 2, 4, 6 and 8 hours during the experiment. The leukocytes of blood from the splenic vein and inferior vena cava were incubated with TRITC-Phalloidin for F-actin, and the images were taken with confocal laser scanning microscope. The The distribution of F-actin at the border or central part of leukocyte was analyzed by using Mias system. Results ratio of F-actin border/center gray value of leukocytes increased at the 2nd, 4th and 6th hour, then declined at the 8th hour in AEP rats, but the ratio of F-actin border/center gray value of leukocytes in the blood from the inferior vena cava declined significantly at the 6th hour in the WPY-treated AEP rats(P < 0.01). At 6 hours following the onset of experimental acute edematous pancreatitis, F-actin polymerization and redistribution in the border region of leukocytes were prominent. CONCLUSION: These evidences indicate that leukocytes play an important role in the development of acute pancreatitis. Traditional Chinese medicine WPY can regulate actin redistribution of leukocytes; moreover, WPY may attenuate the stiffness of leukocytes and render them more flexible and transformable in microcirculation.

Actins↗

PubMed2003

[The change of cryptdin-4 mRNA expression in the intestine of mouse with experimental pancreatitis].

OBJECTIVE: experimental pancreatitis and explore the mechanism of bacterial translocation at the molecular level in mice with severe acute pancreatitis. METHODS: Thirty-six ICR mice were randomly divided into 6 groups with 6 mice in each group. The animals in the experimental groups (from A to E) received seven intraperitoneal injections of caerulein (50 microg/kg body weight) at hourly intervals over 6 hours, and were killed at 9, 18, 24, 48 and 72 hours after the first injection. The control group (F) received intraperitoneal injection of the same volume of saline, and the animals were killed at the 18th hour after the first injection. Blood and pancreatic tissue samples were obtained after the animals were killed. Amylase and pancreatic pathological alterations were observed. The ileum sequential segments were removed from each mouse. The amplification products of RT-PCR were electrophoresed and the images were analyzed by UVI software. RESULTS: Acute necrotizing pancreatitis in ICR mice were induced by the intraperitoneal injection of caerulein at large doses. Markedly pathological lesions were observed at the 18th hour after the first injection of caerulein. And, intestinal cryptdin-4 mRNA expression was down regulated slightly at the 9th hour and most markedly at the 18th hour (P < 0.05). After 24 hours, the cryptdin-4 mRNA expression recovered to the normal level gradually. CONCLUSION: Acquired cryptdin-4 deficiency may play an important role in the pathogenesis of bacterial tanslocation in acute necrotizing pancreatits.

Acute Disease↗

PubMed2002

Hemorheology and expression of neutrophil adhesion molecules CD18 and CD62L in pancreatic microcirculation of Caerulein induced experimental acute pancreatitis.

OBJECTIVE: To explore the changes in hemorheology and expression of neutrophil adhesion molecules CD18 and CD62L in pancreatic microcirculation of Caerulein induced experimental acute pancreatitis (AP). METHODS: The Wistar rats (n = 21) were randomized into three groups. The model of AP was established by subcutaneous injection of Caerulein. The changes of apparent viscosity of whole blood were measured by Low- shear 30 rheometer. The expression of adhesion molecules on the surface of neutrophil in duced by shear stress was used with stationary control. CD18 expression was increased on neutrophils treated with shear rate, and andanalyzed using flow cytometry. RESULTS: Rat treated with Caerulein showed hyperamyleimia (t = 69.029, t = 79.734, P < 0.05). Blood viscosity of two AP groups were significantly elevated (0.512 s(-1): t = 10.725, t = 16.945; 5.96 s(-1): t = 12.781, t = 11.992, P < 0.05). Compared with stationary control, CD18 expression was increased on neutrophil treated with shear rate, and significantly induced with shear rate >/= 94.5 s(-1) (94.5 s(-1): t = 7.403, t = 13.323, t = 16.655; 128.5 s(-1): t = 10.092, t = 28.531, t = 24.563, P < 0.05). The expression of CD62L was less sensitive to low shear rate, and began to be down-regulated significantly when the shear rate >/= 94.5 s(-1) (94.5 s(-1): t = 10.687, t = 19.376, t = 12.848; 128.5 s(-1): t = 26.152, t = 48.402, t = 56.814, P < 0.05). CONCLUSIONS: The changes of apparent viscosity of whole blood, and the effect of fluid shear stress on the expression of neutrophil adhesion molecules CD18, CD62L may play an important role in the pancreatic microcirculatory failure of acute pancreatitis.

Acute Disease↗

PubMed2002

[Structure, function and regulation of MMPs].

The matrix metalloproteinases (MMPs) are a large family of proteolytic enzymes, which are involved in the degradation of many different components of the extracellular matrix. The MMPs have been classified into different groups including collagenases, gelatinases, stromelysins, membrane-type MMPs, etc. There is increasing evidence to indicate that MMPs play important roles in tumour invasion and metastasis. Moreover, MMPs not only play a direct role in tumour invasion by facilitating extracellular matrix degradation, but as a consequence they also have an important role in maintaining the tumour micro-environment and thus promoting tumour growth. In this paper, the structure, function and regulation of MMPs were reviewed.

Matrix Metalloproteinases↗

PubMed2002

[DST and low/ultralow/colo-anal anastomoses laparoscopically in the treatment of low rectal cancer].

OBJECTIVE: To assess the feasibility and adequacy of double stapling technique (DST) and anal sphincter preservation with laparoscopic approach for low rectal cancer. METHODS: DST and low/ultralow/coloanal anastomoses were performed laparoscopically on 30 patients with low rectal cancer. RESULTS: The 30 laparoscopic DST and low/ultralow/colo-anal anastomoses with anal sphincter preservation were successfully completed, and not one of the cases was converted to open procedures. The operation time was 155 min with the ranges from 110 to 320 min. The operative blood loss was 20 ml with a range between 5 and 80 ml. The time of bowel function restoration and post-operative ambulation was 1-2 days after the operation. 14 patients had postoperative analgesic requirement. The hospital stay varied from 5 to 14 days, averaging 8 days, and there were no intraoperative and postoperative complications in the 30 patients. CONCLUSION: Laparoscopic DST and low/ultralow/colo-anal anastomoses for low rectal cancer is a perspective minimally invasive technique, which is feasible, safe and effective. With the use of this technique, surgeons could accomplish higher rates of sphincter preservation, more accurate autonomic nerve preservation and good micturation with decreased postoperative pain and rapid recovery.

Adenocarcinoma↗

PubMed2002

[Laparoscopic total mesorectal excision for low or ultralow anterior resection of rectal cancer with anal sphincter preservation].

OBJECTIVE: To assess the feasibility of laparoscopic total mesorectal excision (TME) for low or ultralow anterior resection of rectal cancer. METHODS: Excision of the mesorectum and low (ultralow) colo-anal anastomoses were performed laparoscopically in 62 patients with low rectal cancer based on the concept of TME and double stapling technique (DST). RESULTS: Sixty-two operations with TME and DST were performed in a totally laparoscopic manner, and only one was converted to open procedures because of dysfunction of coagulation. The operative time was 125 min (110-210 min) and the operative blood loss 20 ml (5-80 ml). The time for bowel function recovery and post-operatively dietary intake was 1-2 days. Twenty-eight patients received postoperative analgesics. Average hospital stay was 8 days (5-14 days). Complications were observed in only 2 of the 62 patients, one had suffered from urinary retention and the other, anastomotic leakage. CONCLUSIONS: Totally laparoscopic excision of the mesorectum for low or ultralow anterior resection of rectal cancer is a minimally invasive technique with sphincter preservation, less postoperative pain, and rapid recovery.

Adult↗