[Research progress on the distribution patterns and surgical dissection of central lymph nodes in left-sided colon cancer].

Lymphatic metastasis is one of the main pathways of colorectal cancer spread and also a crucial factor in patient long-term prognosis. Lymph node dissection in the possible tumor drainage area, particularly the central group of lymph nodes at the root of the tumor-associated supplying artery, is a key and challenging aspect of surgical techniques. Currently, the patterns of lymphatic drainage and the distribution of central lymph nodes in left-sided colon cancer are not well illustrated, and there is no consensus on the necessity and extent of central lymph node dissection. This has led to significant variability in the extent of lymph node dissection among different surgeons in clinical practice, a lack of quality control standards for surgical procedures, and impacts on postoperative treatment strategy and long-term outcomes. Moreover, current research on lymphatic drainage and metastasis is primarily based on traditional anatomy, whereas individualized, precise approaches to lymph node dissection have not been realized. The application of preoperative and intraoperative lymph node imaging techniques based on functional anatomy in colorectal cancer patients is still under exploration.

[Safety and efficacy of adjuvant chemotherapy with oxaliplatin and S-1 for patients with locally advanced gastric cancer after D2 lymph nodes dissection].

Objective: To investigate the safety and efficacy of oxaliplatin combined with S-1 (SOX) as adjuvant chemotherapy after D2 radical gastrectomy for locally advanced gastric cancer. Methods: A descriptive case series study was applied. Case inclusion criteria: (1) locally advanced gastric cancer confirmed by endoscopic biopsy or surgical specimen pathology as gastric adenocarcinoma; (2) receiving D2 radical gastric resection followed by SOX regimen adjuvant chemotherapy. Case exclusion criteria: (1) postoperative pathological TNM stage I or IV; (2) acute complications and emergency surgeries; (3) receiving neoadjuvant therapy; (4) concurrent malignancies and complications compromising patients' treatment or survival; (5) without receiving adjuvant SOX chemotherapy. A total of 94 patients with stage II-III gastric cancer who underwent D2 radical gastrectomy and postoperative adjuvant SOX chemotherapy at department of Gastrointestinal Surgery, Peking University People's Hospital from January 2014 to December 2019 were retrospectively enrolled. Chemotherapy-related adverse events, overall survival (OS) and progression-free survival (PFS) were analyzed. Kaplan-Meier survival analysis was performed and log rank test was used to analyze the difference between groups. P<0.2 or clinically significant indicators in univariate analysis were included in Cox regression model for multivariate survival analysis. Results: Among these 94 patients, there were 65 males and 29 females with an average age of (58.2±12.1) years; 33 patients with hypertension, diabetes mellitus, or cardiovascular and cerebrovascular diseases, 11 patients with family history of gastrointestinal tumors; 59 patients with tumors locating in the antrum or pylorus, 16 patients in the gastric body, 19 patients in the gastric fundus or cardia; 29 patients underwent total gastrectomy, 5 patients underwent proximal subtotal gastrectomy, and 60 patients underwent distal subtotal gastrectomy. In this study, 73 patients (77.7%) completed at least 5 cycles of adjuvant SOX regimen chemotherapy. Grade 3-4 adverse reactions included thrombocytopenia (23.4%, 22/94), nausea and vomiting (18.1%, 17/94) and peripheral neurotoxicity (6.4%, 6/94). Eighty-nine patients (94.7%) completed follow-up with a median follow-up time of 32 months. The 3-year and 5-year OS rates were 89.8% and 83.7%, respectively, and the 3-year and 5-year PFS rates were 81.4% and 78.1%, respectively. Taking 5 chemotherapy cycles as the cut-off point, the 3-year OS rate and 3-year PFS rate were 72.2% and 53.9% in the adjuvant chemotherapy < 5 cycles group, and 93.7% and 87.1% in the adjuvant chemotherapy ≥5 cycles group, respectively; the differences were statistically significant (P=0.029, P=0.006). Univariate analysis showed that the adjuvant chemotherapy < 5 cycles group was associated with worse 3-year OS (P=0.029). Multivariate analysis showed that insufficient chemotherapy cycle (HR=9.419, 95% CI: 2.330-38.007, P=0.002) was an independent risk factor for 3-year OS. Meanwhile, univariate analysis showed that the adjuvant chemotherapy <5 cycles (P=0.006), preoperative CEA > 4.70 µg/L (P=0.035) and adjacent organ resection (P=0.024) were associated with worse 3-year PFS. Multivariate analysis showed that adjuvant chemotherapy <5 cycles (HR=10.493, 95% CI: 2.466-44.655, P=0.001) and adjacent organ resection (HR=127.518, 95% CI: 8.885-1 830.136, P<0.001) were independent risk factors for 3-year PFS. Conclusions: Oxaliplatin combined with S-1 as an adjuvant chemotherapy regimen for locally advanced gastric cancer has high efficacy and low incidence of adverse reactions. At least 5 cycles of SOX regimen adjuvant chemotherapy can significantly improve prognosis of patients with stage II-III gastric cancer.

[Controversy and consideration of high and low ligation of inferior mesenteric artery in radical resection of rectal cancer].

Radical resection is one of the most important treatment for rectal cancer, which requires not only removal of adequate bowel and mesorectum around the tumor, but also thorough lymphadenectomy. Besides, postoperative complications are surgeons' concerns as well. According to different ways to manage inferior mesenteric artery, procedures could be divided into two groups: inferior mesenteric artery (IMA) high ligation and low ligation, which lead to various outcomes of the extent of lymph nodes dissection, survival, preservation of intestinal blood supply, incidence of anastomotic leakage, and postoperative functions including defecation function, urinary function and sexual function. Author believes that for those patients with clinical stage T1, low ligation and D2 lymph nodes dissection could be considered. However, for patients with locally advanced carcinomas (clinical stage T2+or N+), especially suspicious metastasis of lymph nodes around IMA root, high ligation and D3 lymph node dissection is suggested to ensure en bloc resection. As for those patients with high risks for compromised intestinal blood supply, preservation of left colic artery plus D3 lymph nodes dissection might be a feasible way. Intraoperative indocyanine green fluorescent imaging might play a role in quality control of lymphadenectomy.

Inhibition of left ventricular hypertrophy and expression of proto-oncogenes c-myc other than c-fos in myocardium by early captopril treatment in SHR rats.

AIM: To explore the mechanisms by which angiotensin converting enzyme inhibitor (ACEI) prevents the development of left ventricular hypertrophy (LVH). METHODS: Captopril (Cap 100 mg.kg(-1).d(-1)) was given orally to male spontaneously hypertensive rats from intrauterine period to 16 wk of age. Experiments were performed at 40 wk of age. SBP, left ventricular weight to body weight ratio (LVW/BW) were assessed. The levels of c-myc and c-fos mRNA in the left ventricle were measured by Northern blot. RESULTS: Early-onset Cap therapy significantly decreased SBP. After discontinuance of treatment for 24 wk, SBP of SHRcap was still maintained at a lower level. LVW/BW in SHRcap was markedly reduced. The expression of myocardial c-myc mRNA was decreased by 72% in SHRcap compared with that in the untreated SHR, but the expression of myocardial c-fos mRNA was not different between the untreated SHR, SHRcap, and WKY rats. CONCLUSION: Early Cap treatment may permanently prevent the development of hypertension, inhibit LVH. Furthermore, the prevention of LVH is associated with a decrease in c-myc mRNA levels, and the development and regression of left ventricular hypertrophy may be irrelevant to c-fos expression.

[Mechanism of inhibition in left ventricular hypertrophy by captopril treatment in spontaneously hypertensive rats].

To explore the mechanisms by which angiotensin converting enzyme inhibitor (ACEI) prevents the development of left ventricular hypertrophy (LVH), captopril (Cap 100 mg.kg-1/d was administered orally to male spontaneously hypertensive rats from intrauterine period to 16 weeks of age. Male and age-matched untreated WKY rats and SHR were used as controls. Experiments were performed at 40 weeks of age. SBP, left ventricular weight to body weight ratio (LVW/BW), myocardial hydroxyproline (Hypro) and norepinephrine (NE) were determined. The levels of c-myc and c-fos mRNA in the left ventricle were measured by Northern blot. Early-onset Cap therapy significantly decreased SBP at 16 weeks of age. After discontinuance of treatment for 24 weeks, SBP of SHRcap was still maintained at a level lower than that of untreated SHR. LVW/BW and Hypro in SHR cap were markedly reduced. The expression of myocardial c-myc mRNA (n = 5) was decreased by 72% in SHRcap compared with that in the untreated SHR, but the expression of c-fos mRNA (n = 7) and NE was not different between the untreated SHR, SHRcap and WKY rats. These results indicate that early Cap treatment may permanently prevent the development of hypertension, inhibit myocardial hypertrophy (MH), and interstitial fibrosis. Furthermore, the prevention of MH is associated with a decrease in myocardial c-myc mRNA levels, and the development and regression of MH may be irrelevant to proto-oncogene c-fos expression.

Study of microencapsulation for pituitary transplantation: capsule preparation and in vitro study.

We have developed microcapsules using sodium alginate (SA) and Poly-L-Lysine (PLL). A factorial design method of screening was chosen to study influences of different experimental parameters on size and stability of the capsules. We found that air flow affects initial size of the capsules significantly, while the molecular weight (MW) of PLL and incubation time have a positive impact on the expansion when capsules are incubated in sodium citrate (SC). When the capsules were continuously shaken in an attempt to mimic in vivo environmental conditions, those capsules made with optimal parameters (0.1% PLL, 42,000 MW, incubated for 6 minutes; 1.5% SA, incubated for 4 minutes; SC bath 4 minutes; 25# needle; air flow 14L/min) were still intact after 30 days and not totally ruptured until 90 days, while those developed with less strict parameters were ruptured within 2 hours in 50%. We also encapsulated human pituitary adenoma cells using PLL of 80,000 MW and cultured them for 9 days. Adenoma cells, both encapsulated or non-encapsulated, secreted the same amount of hormones. Our preliminary study suggests that selecting optimal combinations of experimental parameters is essential in developing durable microcapsules, which may be potentially used for pituitary transplantation in vivo.

Study of microencapsulated pituitary transplantation. Preparation of the capsule and its property.

Microencapsules for pituitary transplantation was successfully developed with sodium alginate and poly-L-lysine (average molecular weight MW 70,000). The permeability of the capsular membrane (CM) was tested. The results showed that 60% of growth hormone (GH), thyroid stimulating hormone (TSH), prolactin (PRL) have passed through the membrane within 3 hours, and reached equilibrium up to 6 hours, suggesting that pituitary hormones (MW 20,000) could pass through CM freely. Bovine serum albumin (MW 67,000) in 50% could also permeate the CM in 3 hours and reached equilibrium up to 24 hours. While immunoglobulin (Ig, MW > 150,000) did not penetrate the CM completely. This study revealed that the microencapsular membrane we made effected immuno-isolation and could be used for pituitary transplantation.

[A voltage-dependent potassium channel of outward rectifier type in plasma membrane of oocyte from toad, Bufo bufo gargarizans].

Membrane properties of the fully-grown oocytes from toad, Bufo bufo gargarizans, were studied by using voltage-clamp technique. It was found that a sustained outward current was elicited by membrane depolarization to -30 mV or more positive value. The increase of the current was nearly proportional to the degree of depolarization. The peak value of the current ranged 2-5 microA at a membrane potential of 20 mV in oocytes from different toads. The current was inhibited by antagonists of potassium channel, TEA and 4-AP. The concentration of TEA capable of inhibiting half of the current was 2.6 mmol/L. Chloride channel antagonist 9-AC (2.5 mmol/L) had no effect on the current. Triple the extracellular calcium concentration did not show any effect either. The reversal potential of the current varied with an increase of 47.3 mV per decade change of the extracellular potassium concentration. Changing extracellular concentration of sodium or chloride did not shift the reversal potential. It was concluded that the outward current was a voltage-activated potassium current. The voltage-dependent potassium current decreased after treatment of the oocytes with progesterone to a state of maturation. A large decrease of the current (to about 1/20 of the control) occurred to the oocytes obtained from hibernating toads while a less striking decrease of the current (to about 1/3 of the control) was observed in the oocytes from toads all year round reared at 25-30 degrees C.

Development of a monoclonal antibody specific for the gamma chain of the T-cell antigen receptor using an open reading frame expression vector.

To develop an anti-framework monoclonal antibody (mab) specific for the gamma (gamma)-chain of the T-cell antigen receptor (TCR), we expressed a part of the constant region of the gamma-chain (C gamma 2 gene segment) in E. coli using the pWR590 vector. This plasmid contains the E. coli lac promoter, operator, a truncated beta-galactosidase (beta-gal) gene (coding for the first 590 of the 1,007 amino acids of the beta-gal) and a polylinker region (at the 3' end of the beta-gal) containing nine restriction sites. These can be cleaved by any one of eight common restriction enzymes, permitting the introduction of the DNA fragment of interest. We employed the pT gamma 1 gamma-chain cDNA probe, which like the vast majority of the gamma-chain specific probes is aberrant and contains an in-frame stop codon at the junction of V and J regions. Computer analysis of the pT gamma 1 sequence revealed several MaeIII restriction sites that could result in a number of fragments. One of these fragments consisted of 245 base pairs (nucleotides 404-648) and contained most of the CI exon of the C gamma 2. Successful insertion of this fragment to the pWR590 vector was confirmed using restriction enzyme analysis. The C gamma insert was 12% of the construct. Expression of the pWR590-HpT gamma 1 recombinant plasmid in E. coli followed by SDS-PAGE analysis revealed a hybrid protein with a molecular weight of 85 kd which constituted at least 25% of the total E. coli insoluble protein. In contrast, cells transformed with the control pWR590 vector without insert expressed a 78 kd polypeptide chain. We developed several mabs against the pWR590-HpT gamma 1 hybrid protein by fusing spleen lymphocytes from BALB/c mice immunized with the pWR590-HpT gamma 1 protein, with cells of the NS1 mouse myeloma cell line. Screening of the mabs was carried out by ELISA against the pWR590-HpT gamma 1 hybrid protein and the control pWR590 beta-gal protein (beta-gal 590), derived by expressing in E. coli the pWR590 vector without gamma-chain insert. Two groups of mabs were obtained, those reacting with the pWR590-HpT gamma 1 hybrid protein only and those reacting with both the hybrid and the control beta-gal 590 proteins. The specificity of these mabs was further studied by Western blotting with similar results.(ABSTRACT TRUNCATED AT 400 WORDS)

[Dibutyryl cyclic adenosine monophosphate (DBc-AMP) in the treatment of recurrent malignant gliomas--report of 7 patients].

It has been demonstrated, by experiments, that DBc-AMP can induce biochemical and morphological changes in cultured glioma cells. In this paper, seven recurrent malignant glioma patients, who had received operation, radiotherapy and chemotherapy, were treated with DBc-AMP by injecting into the tumor feeding artery in 1 patient and directly into the tumor cavities in 6 patients. The results showed that although no improvement of symptoms was observed except the case by intraarterial injection, the IgG and IgA levels were elevated and tumor volume was reduced as shown by enhancement CT scan in 4 patients. It suggests that this method be a better adjuvant therapy for recurrent malignant gliomas.