In this experiment, the PAP was used as a specific marker to label the follicular dendritic cells (FDC) and their possible precursors in the spleens of postnatal rats at 21, 27, 34, 41 and 48 days respectively, and the changes of the labeled cells were studied under TEM. In 21-day-old rats the labeled cells were of the histological feature resembling fibroblastic reticulum cells(FRC). As the rats getting elder, the shape and structure of the labeled cells changed. The shape of t he cells and nuclei changed from ellipse to irregular. The heterochromatin decreased and so did the microfilaments in the cytoplasm. The cytoplasmic processes increased in number, length and complexity. The relatively smooth cell surface became folding and invaginating. By the 48 days after birth the labeled cells possessed the features of the FDC. The result implys that the FDC might originate from FRC.

Phagocytic capacities of both dendritic cells (DC) and macrophages(M?) in the DC-enriched fractions isolated from rat spleen were comparatively observed under electron microscope. Experiments were divided into two groups: in vitro and in vivo. In group 1, candida albicans(CA), cock red blood cells (CRBC) and CRBC opsonized with rat antiserum against CRBC (OCRBC) used as phagocytic markers were incubated with the DC-enriched fractions for 1h at 37℃ separately in vitro. In group 2, colloidal carbon (CC) (india ink) and heat killed Candida albicans (HKCA) were injected in vivo. The animals were sacrificed 18h later and DC-enriched fractions were isolated from the spleens. The results are as follow: generally, in the cytoplasm of DC, no phagocytic markers were identified except a few of DC ingested a small amount of CC in vivo and few CA occationally in vitro, while M? under the same conditions, ingested a lot of the substances mentioned above. It indicates that spleen M? phagocytose actively either to immunogenic or non-immunogenic, opsonized or non-opsonized particles (especially to opsonized particles), while DC in the same preparations are not.

Expression of Ia-antigen on cells in lymphoid dendritic cells (LDCs)-enrt- ched fractions isolated from unstimulated rat spleens was observed with ABC immunoperoxidase and indirect immunofluorescent staining methods. The results appeared that there were three types of cells in stained preparaions: 1. Large cells with dendritic processes on their surfaces showed dark brown in colour with ABC staining method and emitted intense light-green fluorescence with immuno- fluorescent staining technic. 2. Large rounded or ovoid cells without obviously ramifications revealed colourless or light yellow-brown in colour with ABC sta- ining method and emitted no or weak yellow-green fluorescence with immuno- fluorescent staining technic. 3. Spherical lymphocytes of varying in size were similar to type 2 cells in immunoreactivity. The results of SEM and S-100 pro- tein staining confirmed that these three types of cells were LDCs, macrophages and lymphocytes in turn. It is indicated that LDCs consistently expressed Ia- antigen in large amount on their surfaces.

Objective: This study aimed to compare the short- and long-term outcomes of laparoscopy-assisted radical gastrectomy between elderly and non-elderly patients with gastric cancer. Methods: A total of 219 patients who underwent laparoscopy-assisted radical gastrectomy in the Department of Gastrointestinal Surgery IV, Peking University Cancer Hospital & Institute from April 2009 to October 2013 were included in this retrospective study. All patients were divided into elderly (≥65 years) and non- elderly (<65 years)groups. We compared these groups based on clinicopathological characteristics, postoperative morbidities, and survival. Results:Theelderly group showed higher ASA scores and higher number of preoperative comorbidities (P<0.05). The operative time, blood loss,and conversion rate did not differ significantly between the groups (all P>0.05). The mean time to first ambulation in elderly group was 2.2±2.3d while first ambulation time in the non-elderly group was 1.4±1.3d,which showed significant difference between the two groups (P<0.05). No significant differences were observed between groups in terms of postoperativemorbidities (34.8％ vs. 28.5％, P> 0.05) as well as 3-year disease-free survival and overall survival (P>0.05). However, the elderly patients withpostoperative morbidities experienced significantly poorer overall survival rate than non-elderly patients (44.5％ vs. 70.5％, P<0.05). Conclusion: Laparoscopy-assisted gastrectomy can be safely and successfully performed in an elderly population with acceptable short- and long-term outcomes.Enhanced perioperative treatment is necessary to improve postoperative outcomes.

Background and aim:Few studies have reported hepatitis B surface antigen(HBsAg)kinetics after nucleos(t)ide analog(NA)discontinuation in patients with noncirrhotic chronic hepatitis B(CHB).The study specifically investigated long-term HBsAg kinetics after NA discontinuation. Methods:Between January 2014 to January 2024,this study prospectively enrolled 106 outpatients with noncirrhotic CHB who met the discontinuation criteria after NA consolidation treatment.Demographic,clinical,and laboratory data were collected and analyzed after NA discontinuation. Results:Ninety-six patients who finished 5 years of follow-up were included.HBsAg remained unde-tectable in 29 patients with end of treatment(EOT)HBsAg negativity.Among 67 patients with EOT HBsAg positivity,HBsAg seroclearance occurred in 12(17.9％)patients with an estimated annual inci-dence of HBsAg seroclearance of 3.6％.Patients with EOT HBsAg levels of ≤1000 IU/mL had a higher HBsAg seroclearance rate than those with EOT HBsAg levels of＞1000 IU/mL(33.3％vs.5.4％).The pro-portion of patients with HBsAg ≤1000 IU/mL increased during follow-up.Logistic regression analysis indicated that the EOT HBsAg level was an independent factor for HBsAg seroclearance and an HBsAg level decline exceeding 1 log10 IU/mL.The optimal EOT HBsAg cutoff for both HBsAg seroclearance and an HBsAg level decline exceeding 1 log10 IU/mL was 359 IU/mL. Conclusions:Patients with EOT HBsAg negativity experienced no relapse and maintained HBsAg sero-clearance during 5 years of follow-up after NA discontinuation.A higher HBsAg seroclearance rate can be obtained in patients with EOT HBsAg levels of ≤1000 IU/mL during 5 years of follow-up after NA discontinuation.Close monitoring and proper NA retreatment are recommended to guarantee the safety of NA discontinuation.

Purpose: Recently, totally laparoscopic gastrectomy has been gradually accepted by surgeons worldwide for gastric cancer treatment. Complete dissection of the lymph nodes and the establishment of the surgical margin are the most important considerations for curative gastric cancer surgery. Previous studies have demonstrated that indocyanine green (ICG)-traced laparoscopic gastrectomy significantly improves the completeness of lymph node dissection. However, it remains difficult to identify the tumor location intraoperatively for gastric cancers that are staged ≤T3. Here, we investigated the feasibility of ICG fluorescence for lymph node mapping and tumor localization during totally laparoscopic distal gastrectomy. Materials and Methods: Preoperative and perioperative data from consecutive patients with gastric cancer who underwent a totally laparoscopic distal gastrectomy were collected and analyzed. The patients were categorized into the ICG (n=61) or the non-ICG (n=75) group based on whether preoperative endoscopic mucosal ICG injection was performed. Results: The ICG group had a shorter operation time and less intraoperative blood loss.Moreover, significantly more lymph nodes were harvested in the ICG group than the non-ICG group. No pathologically positive margin was found and there was no significant difference in either the proximal or distal surgical margins between the 2 groups. Conclusions Near-infrared fluorescence imaging with ICG can be successfully used in totally laparoscopic distal gastrectomy, and it contributes to both the completeness of D2 lymph node dissection and confirmation of the gastric transection line. Well-designed prospective randomized studies are needed in the future to fully validate our findings.

OBJECTIVE: To investigate the risk factors of postoperative pulmonary infection (PPI) in patients over 60 years of age with gastric cancer after radical gastrectomy. METHODS: Clinicopathological data of 373 patients over 60 years of age who underwent radical gastrectomy at Department IV of Gastrointestinal Cancer Center, Peking University Cancer Hospital, from April 2009 to December 2016 were retrospectively collected in this case-control study. The clinicopathological characteristics of patients with postoperative pulmonary infection (including postoperative atelectasis) and those without pulmonary infection were compared. A Student t-test (reported as Mean±SD if data matching normal distribution) or Mann-Whitney U test [reported as median (quartile) if data did not conform to normal distribution] was used to analyze continuous variables. A χ² test or Fisher exact tests (reported as number and percentage) was used for categorical variables. Multivariable logistic regression was used to analyze the risk factors for pulmonary infection after operation of gastric cancer.PPI was defined as postoperative patients with elevated body temperature (>38.0 degrees centigrade) for more than 24 hours; cough and expectoration; positive sputum bacteria culture;recent infiltration, consolidation or atelectasis confirmed by chest imaging examination. RESULTS: Among 373 patients, 50 cases had PPI(13.4%, PPI group), 323 cases had no PPI(86.6%, non-PPI group). There were 39 (78.0%) and 178(55.1%) patients with comorbidities (including hypertension, diabetes and cardiopulmonary disease) preoperatively in PPI and non-PPI group, respectively. The difference between two groups was statistically significant (χ²=9.325,P=0.002). The incidence of preoperative hypoalbuminemia in PPI group was also significantly higher than that in non-PPI group [10.0%(5/50) vs. 3.1% (10/323),χ²=4.098, P=0.048]. Compared to non-PPI group, the rate of total gastrectomy [54.0%(27/50) vs. 34.4% (111/323), χ²=12.501, P=0.002], postoperative wound pain [34.0%(17/50) vs. 11.8% (38/323),χ²=16.928, P<0.001], secondary operation [6.0%(3/50) vs. 0.6% (2/323), χ²=6.032, P=0.014] and the rate of gastric tube removal later than 7 days postoperatively [96.0%(48/50) vs. 84.5%(273/323),χ²=4.811, P=0.028] were significantly higher in PPI group, respectively. The postoperative hospital stay was also prolonged in PPI group [16.0(9.5) days vs. 12.0(5.0) days, U=4 275.0, P<0.001]. Multivariate logistic regression analysis showed that preoperative comorbidities (OR=4.008, 95%CI:1.768-9.086, P=0.001), abdominal infection (OR=3.164, 95%CI:1.075-9.313, P=0.037), and wound pain (OR=3.428, 95%CI:1.557-7.548, P=0.002) were independent risk factors for PPI in patients over 60 years of age with gastric cancer. Furthermore, 50 patients with pulmonary infection were classified according to the length of latency and the type of infection. The patients with PPI latency ≤ 3 days were classified as early onset (34 cases, 68.0%), and those with latency ≥ 4 days as delayed onset (16 cases, 32.0%); PPI combined with surgical infection (including anastomotic leakage, abdominal infection, duodenal stump leakage, wound infection, etc.) was classified into mixed infection group (13 cases, 26.0%), with non-surgical infection as simple infection group (37 cases, 74.0%). The results showed that the pulmonary infection occurred 0 to 12 days (median 3 days) before surgical infection in mix infection group. The incidence of previous chronic obstructive pulmonary disease (COPD) in patients with early onset was significantly higher than that in patients with delayed onset [17.6%(6/34) vs. 0, χ²=5.005, P=0.025], and the incidence of mixed infection in patients with delayed onset was significantly higher than that in patients with early onset [50%(8/16) vs. 14.7%(5/34), χ²=6.730, P=0.009],but there was no significant difference in postoperative hospital stay between the two groups[17.0(9.8) days vs. 14.0(9.5) days, U=224.0, P=0.317]. CONCLUSIONS Postoperative pulmonary infection is common in gastric cancer patients over 60 years of age. Preoperative comorbidities, abdominal infection and wound pain are independent risk factors for postoperative pulmonary infection. Pulmonary infection within 3 days after operation is associated with preoperative COPD. For patients suffering from PPI after the 4th day,attentions should be paid to abdominal infection and anastomotic leakage.
Age Factors ; Anastomotic Leak ; etiology ; Case-Control Studies ; Gastrectomy ; adverse effects ; methods ; Humans ; Intraabdominal Infections ; etiology ; Middle Aged ; Pneumonia ; etiology ; Pulmonary Atelectasis ; etiology ; Pulmonary Disease, Chronic Obstructive ; complications ; Retrospective Studies ; Risk Factors ; Stomach Neoplasms ; complications ; surgery

OBJECTIVE: To evaluate the safety and feasibility of laparoscopy-assisted total gastrectomy in gastric cancer patients over 65 years old. METHODS: Clinical, pathological and follow-up data of 188 gastric cancer patients who underwent laparoscopy-assisted total gastrectomy at Department IV of Gastrointestinal Cancer Center, Peking University Cancer Hospital, from April 2009 to December 2016 were collected for a retrospective cohort study. INCLUSION CRITERIA: ECOG performance score 0-1; preoperative gastroscopy discovered gastric masses, and pathological biopsy confirmed adenocarcinoma; distant metastases were excluded by image examination; preoperative cardiopulmonary function was normal; preoperative blood routine test, liver and renal function, and coagulation function were normal; laparoscopy-assisted total gastrectomy was performed. EXCLUSION CRITERIA: intraoperative laparoscopic exploration indicated abdominal and/or pelvic peritoneal metastasis; free cancer cells in peritoneal cavity; conversion to laparotomy during laparoscopic surgery. Patients were divided by age into 2 groups, ≥ 65 years old group(59 cases) and < 65 years old group (129 cases). The perioperative conditions and postoperative complications between two groups were compared, and the high risk factors of postoperative complications in patients over 65 years old were analyzed. RESULTS: All the patients were operated by the same operation team. The incidence of comorbidities was 44.1%(26/59) in the ≥ 65 years old group, which was significantly higher than 20.2% (26/129) in the < 65 years old group (χ²=11.570, P=0.001). The incidence of cardia/fundus cancer was 64.4%(38/59) in the ≥ 65 years old group, which was also significantly higher than 40.3% (52/129) in the < 65 years old group (χ²=16.625, P=0.001). The number of retrieved lymph nodes in the ≥65 years old group was significantly lower than that in the < 65 years old group (28.9±10.7 vs. 36.1±15.4, t=3.271, P=0.001). The total morbidity of complications was 13.8%(21/188) and the mortality within 30 days after operation was 1.6%(3/188). The morbidity of postoperative complications and the mortality within 30 days after operation were 20.3%(12/59) and 3.4%(2/59,respectively) in the ≥ 65 years old group, which were slightly higher than those in the <65 years old group [10.9%(14/129) and 0.8%(1/129)], without significant difference(both P>0.05). Multivariate logistic regression analysis showed that preoperative comorbidities(OR=0.223, 95%CI:0.053 to 0.944, P=0.041) was an independent risk factor for postoperative complications in patients aged ≥ 65 years old undergoing laparoscopy-assisted total gastrectomy. The median survival time was 21.3 months and the overall 5-year survival rate was 50.0%. The 5-year survival rate was 45.5% and 57.5% in patients aged ≥ 65 and < 65 years, respectively, and there was no significant difference(P=0.205). CONCLUSIONS Laparoscopy-assisted total gastrectomy is safe and effective in the treatment of gastric cancer patients ≥ 65 years old. Age is not a contraindication of laparoscopy-assisted total gastrectomy.
Aged ; Cohort Studies ; Gastrectomy ; instrumentation ; Humans ; Laparoscopy ; Postoperative Complications ; Retrospective Studies ; Stomach Neoplasms ; surgery ; Treatment Outcome