Natural killer cell cytotoxicity assay with time-resolved fluorimetry

A new time-resolved fluorimetric method for the measurement of natural killer (NK) cell cytotoxicity has been developed by labelling the target cell K562 with a new synthesized fluorescence marker KLUK. The method has advantages of higher sensitivity, time-saving, good reproducibility and has no radioactivity problems. A satisfactory result is obtained by comparing it with 51Cr release method. It demonstrates that the new marker provides an alternative to currently used radioactive markers for the assessment of in vitro cellular cytotoxicity.

[Effects of Astragalus polysaccharides and ginsenosides of Ginseng stems and leaves on lymphocytes membrane fluidity and lipid peroxidation in traumatized mice]

From days 0 to 3 posttrauma, daily administration of Astragalus polysaccharides (250mg/kg,ip) and ginsenosides of ginseng stems and leaves (50mg/kg,sc) can elevate significantly the lymphocytes membrane fluidity of plasmalemma, mitochondria and microsome from spleen,thymus and mesenteric lymph nodes in traumatized mice, reduce lipid peroxide levels, and increase superoxide dismutase activities in serum and lymphocytes from traumatized mice.

[Is anomalous junction of pancreaticobiliary duct related to pancreatitis]

Among 1779 patients was subjected to endoscopic retrograde cholangiopancreatography (ERCP), an anomalous junction of pancreaticobiliary duct (AJPB) was found in 48 (AJPB group), a normal common channel was found in 734 (control group A), and a non-common channel was found in 284 (control group B). Another 713 patients were excluded because the pancreaticobiliary duct was not clear. In AJPB group, the length of the common channel ranged from 15 to 35mm (17.9 +/- 5.06mm). 16 patients were of P-B type and 32 patients B-P type. As to pancreatitis there were 21 patients in AJPB group, 48 in control group A and 22 in control group B. As to acute pancreatitis (AP) there were 4 patients in AJPB group, 9 patients in control group A and 4 patients in control group B. In AJPB group, there were 13 P-B type patients and 8 B-P type patients with pancreatitis. The incidence of pancreatitis in AJPB group was larger than that in control group A or B (P < 0.01), and in AJPB group, the incidence of pancreatitis of B-P type was less than that of P-B type (P < 0.01). The results showed that AJPB is related to pancreatitis. We consider that AJPB is an anatomic factor inducing pancreatitis. The pancreatic ductal high pressure may play an important role in the pathogenesis of pancreatitis caused by AJPB.

The disintegration of absorbable suture materials on exposure to human digestive juices: an update

This is a comparative study of the disintegration of absorbable sutures when incubated in human gastric juice, bile, pancreatic juice, and their mixture. Plain catgut rapidly lost its strength in each of these digestive fluids. Chromic catgut was susceptible to digestion although it retained most of its strength in bile for two weeks. Synthetic absorbable sutures, polyglycolic acid or its derivatives (Dexon "S", Dexon Plus, and Maxon), maintained most of their strength for 2 weeks, disintegrating only after 5 to 8 weeks. Controls of saline or human plasma had little demonstrable effect. As a further control, silk maintained its strength under each exposure. Although catgut is widely used, the study suggests that it disintegrates too rapidly, at least under the conditions tested, to be appropriate for alimentary tract surgery, whereas the synthetic sutures maintained their integrity rather well for the 2 to 3 weeks needed for visceral wound healing. The data suggest that slowly absorbed synthetic sutures may be particularly useful in pancreatic or biliary anastomoses where a single layer is preferable and where a nonabsorbable suture offers inherent disadvantages.

Prognostic value of serum CA 19-9 levels in pancreatic adenocarcinoma

Thirty-eight patients with histologically proven pancreatic adenocarcinoma were investigated to establish the utility of serum CA 19-9 as a prognostic indicator. CA 19-9 assays were performed serially during the course of the disease. In four patients with negative Lewis blood type, the CA 19-9 levels remained essentially normal throughout the disease course. In the remaining 34 patients, (1) CA 19-9 levels were significantly lower in patients with tumor size no larger than 5 cm in diameter, and in patients with resectable tumors than in those with tumor size larger than 5 cm or with unresectable tumors (p less than 0.01). 2) CA 19-9 levels dropped sharply after resection in all 11 resectable patients, whereas no significant change was found after laparotomy without resection. (3) The average survival time in seven patients whose CA 19-9 levels returned to normal after resection was significantly longer than in those four patients with postoperative CA 19-9 levels that decreased but did not return to normal (21.9 versus 8.7 months, p less than 0.05). (4) In 6 of 11 patients who underwent resection, recurrent elevation of CA 19-9 preceded changes detectable by computed tomography or clinical examination by 2 to 9 months. (5) In 23 patients who died of pancreatic carcinoma, 15 (65%) had an obvious rise in CA 19-9 level before death. There was a correlation between the doubling time of the CA 19-9 serum level and survival time (r = 0.5, p less than 0.05). Because it can be demonstrated that the reduction of tumor burden by resection lowers serum CA 19-9 levels, serum CA 19-9 levels may be a useful indicator of whether other forms of treatment such as radiation therapy or chemotherapy also reduce the tumor burden.

Detection of occult metastases in pancreatic adenocarcinoma with anticytokeratin antibody

Fifty-six lymph nodes excised from 11 patients with pancreatic adenocarcinoma were studied for evidence of metastasis by standard light microscopy and immunohistochemistry using an anticytokeratin monoclonal antibody. Eight of 56 nodes contained metastatic carcinoma as demonstrated by conventional techniques. By immunohistochemistry, positive-staining cells were easily identified. In 10 of 56 nodes, the positive staining was accompanied by cytologic atypia, changes consistent with malignancy. In seven additional nodes, positive-staining cells were present, but cytologic atypia was lacking. The use of immunohistochemistry facilitated recognition of malignant cells and raised questions that single-cell metastasis may be present. Positive staining for cytokeratin should prompt a close examination of cells to determine if morphologic features of malignancy are present.

Occupational exposure to benzene in China

Of a total of 528,729 workers exposed to benzene or benzene mixtures in China, 508,818 (96.23%) were examined. Altogether 2,676 cases of benzene poisoning were found, a prevalence of 0.15%. A higher prevalence of benzene poisoning was found in the cities of Hangjou, Hefei, Nanjing, Shenyang, and Xian. The geometric mean concentration of benzene in 50,255 workplaces was 18.1 mg/m3 but 64.6% of the workplaces had less than 40 mg/m3. There was a positive correlation between the prevalence of benzene poisoning and the concentration in shoemaking factories. The prevalence of benzene induced aplastic anaemia in shoemakers was about 5.8 times that occurring in the general population. The results of this investigation show the need for a practicable hygiene standard to prevent benzene poisoning.