The effect of external gamma-irradiation on 59Fe release in vitro from alveolar macrophages previously having ingested 59Fe-iron hydroxide colloid

The effect of external gamma-irradiation on the digestive function of rat alveolar macrophages (AM) was studied by using the in vitro assay system, where the 59Fe release from AM engulfing 59Fe-iron hydroxide colloid was measured as an indicator of their digestive capability. Graded doses of gamma-irradiation up to 100 Gy had no effect on the extracellular release of 59Fe in AM cultured at 4 and 37 degrees C for 8-72 hrs postirradiation. When 10 mM Ca-DTPA was added to the culture medium, the 59Fe release was slightly depressed by irradiation at a dose of 30 Gy. It is apparent from these results that gamma-irradiation had no effect on the 59Fe transfer between cell and medium, and little effect on the catabolism of 59Fe-colloid in rat AM.     

Study of para-aortic lymph node metastasis of gastric cancer subjected to superextensive lymph node dissection

Para-aortic lymph nodes (n4), were dissected out to the technical extreme (superextensive lymph node dissection) from 129 gastric cancer cases, and were subjected to the histological study for metastasis. Following observations led us to the conclusions in reference to the significance of n4 node dissections on curability of surgery. 1) Among 25 cases with n4(+) metastasis n3 was free [n3(-)] in 11 cases (44.0%). 2) ps(+) cancer presented high rate of n4(+) (31.5%). 3) n4(+) occurred irrespective of the location of the cancer, with particularly high rate of occurrence among CMA and cancers. 4) The rate of the metastasized lymph nodes to the total number of the n4 lymph nodes, was found low (34.9%) in cases with n3(-), and high (90.1%) with n3(+). 5) The cumulative survival rate of the cases with n4(+) was found significantly high with n3(-), as compared to n3(+) cases. The lymphatic drainage from the stomach seems more direct and/or more abundant to the n4 than to the n3 nodes. Such observation coincides with our experience that the n4 nodes are involved in metastasis in earlier timing and in higher incidence than n3 nodes. These results warn the present evaluation of curability in which the n4 node dissection is not performed. It is our opinion that the thorough dissection extended to the n4 nodes (superextensive lymph node dissection) is warranted, particularly in order to improve the curability of n3(-)-n4(+) cases.     

Carcinoma of the main hepatic duct junction: indications, operative morbidity and mortality, and long-term survival

Carcinoma of the main hepatic duct junction tends to spread extensively along the hepatic ducts into the liver parenchyma. Therefore extensive resection of the bile ducts combined with hepatic resection is the procedure of choice. Between January 1973 and April 1989, 25 of 50 patients with this type of carcinoma underwent resection, a resectability rate of 50%. One patient died of staphylococcal sepsis on the postoperative day 42 after right trisegmentectomy and resection of the bile ducts, a hospital death rate of 4%. Twenty-four patients were discharged from the hospital. The 5-year actuarial survival rate calculated by the Kaplan-Meier method was 19%. Four patients lived longer than 5 years after surgery; the longest survival was 9 years after right trisegmentectomy and resection of the bile ducts. These four patients had clear margins at the resected bile ducts. This article was designed to clarify the point at issue by presenting our results in terms of indications, operative morbidity and mortality, and long-term survival.     

Hypoosmotic swelling test of sperm

For the diagnosis and evaluation of the therapy for male infertility and for predicting the outcome of AIH and IVF-ET, technically simple, replicable tests that can be performed virtually anywhere and that have definite reliability are required. The results of the HOS test correlate well with the functions of the sperm cell membrane, indicating such aspects as motility, and it is thought to be a particularly effective test of human sperm fertility. Because the HOS test reflects the functions and integrity of the sperm cell membrane, it should be possible to use it to predict the potential for fertilization of frozen sperm.     

Skeletal unloading induces resistance to insulin-like growth factor-I (IGF-I) by inhibiting activation of the IGF-I signaling pathways.

We showed that unloading markedly diminished the effects of IGF-I to activate its signaling pathways, and the disintegrin echistatin showed a similar block in osteoprogenitor cells. Furthermore, unloading decreased alphaVbeta3 integrin expression. These results show that skeletal unloading induces resistance to IGF-I by inhibiting activation of the IGF-I signaling pathways at least in part through downregulation of integrin signaling. INTRODUCTION: We have previously reported that skeletal unloading induces resistance to insulin-like growth factor-I (IGF-I) with respect to bone formation. However, the underlying mechanism remains unclear. The aim of this study was to clarify how skeletal unloading induces resistance to the effects of IGF-I administration in vivo and in vitro with respect to bone formation. MATERIALS AND METHODS: We first determined the response of bone to IGF-I administration in vivo during skeletal unloading. We then evaluated the response of osteoprogenitor cells isolated from unloaded bones to IGF-I treatment in vitro with respect to activation of the IGF-I signaling pathways. Finally we examined the potential role of integrins in mediating the responsiveness of osteoprogenitor cells to IGF-I. RESULTS: IGF-I administration in vivo significantly increased proliferation of osteoblasts. Unloading markedly decreased proliferation and blocked the ability of IGF-I to increase proliferation. On a cellular level, IGF-I treatment in vitro stimulated the activation of its receptor, Ras, ERK1/2 (p44/42 MAPK), and Akt in cultured osteoprogenitor cells from normally loaded bones, but these effects were markedly diminished in cells from unloaded bones. These results were not caused by altered phosphatase activity or changes in receptor binding to IGF-I. Inhibition of the Ras/MAPK pathway was more impacted by unloading than that of Akt. The disintegrin echistatin (an antagonist of the alphaVbeta3 integrin) blocked the ability of IGF-I to stimulate its receptor phosphorylation and osteoblast proliferation, similar to that seen in cells from unloaded bone. Furthermore, unloading significantly decreased the mRNA levels both of alphaV and beta3 integrin subunits in osteoprogenitor cells. CONCLUSION: These results indicate that skeletal unloading induces resistance to IGF-I by inhibiting the activation of IGF-I signaling pathways, at least in part, through downregulation of integrin signaling, resulting in decreased proliferation of osteoblasts and their precursors.     

Direct determination of benzalkonium chloride in ophthalmic systems by reversed-phase high-performance liquid chromatography

High-performance liquid chromatography has been used to quantitate benzalkonium chloride (alkylbenzyldimethylammonium chloride) in complex ophthalmic formulations at or below concentration levels of 50 ppm. The method involves a one-step dilution for sample preparation and direct injection; therefore, recovery and/or conversion problems are nonexistent. The assay is quick, specific, reproducible, and simple. This new approach makes routine determinations far simpler than previous methods and is especially useful for product stability studies and quality control procedures.     

Factor VIII lability, protein C and other vitamin K-dependent proteins

The stability of factor VIII was studied in plasmas from patients on long-term warfarin therapy. The percent residual factor VIII activity (F.VIII:C) after incubation at 37 degrees C for 4 hr was higher in warfarinized patients than in normal subjects; 76.9 +/- 10.8% (mean +/- SD) of the initial F.VIII:C in the patients versus 61.6 +/- 5.8% in normal subjects (p less than 0.001). On the whole, neither protein C nor vitamin K-dependent coagulation factors except factor VII activity (F.VII:C) correlated with the residual F.VIII:C. There was a negative and weak correlation between the residual F.VIII:C at 4 hr and either the initial F.VIII:C or F.VII:C. Another experiment using protein C depleted plasma showed a relatively enhanced stability of F.VIII:C in the protein C deficiency. These results indicate that factor VIII is more stable in warfarinized plasma, and that protein C and vitamin K-dependent coagulation factors are not the sole, main factor responsible for such a phenomenon.