The alkaloid Berberine inhibits the growth of Anoikis-resistant MCF-7 and MDA-MB-231 breast cancer cell lines by inducing cell cycle arrest.

Berberine is a pure phenanthren alkaloid isolated from the roots and bark of herbal plants such as Berberis, Hydrastis canadensis and Coptis chinensis. Berberine has been established to inhibit the growth of breast cancer cells, but its effects on the drug resistance and anoikis-resistance of breast cancer cells have yet to be elucidated. Anoikis, or detachment-induced apoptosis, may prevent cancer progression and metastasis by blocking signals necessary for survival of localized cancer cells. Resistance to anoikis is regarded as a prerequisite for metastasis; however, little is known about the role of berberine in anoikis-resistance. We established anoikis-resistant cells from the breast cancer cell lines MCF-7 and MDA-MB-231 by culturing them on a Poly-Hema substratum. We then investigated the effects of berberine on the growth of these cells. The anoikis-resistant cells had a reduced growth rate and were more invasive than their respective adherent cell lines. The effect of berberine on growth was compared to that of doxorubicine, which is a drug commonly used to treat breast cancer, in both the adherent and anoikis-resistant cell lines. Berberine promoted the growth inhibition of anoikis-resistant cells to a greater extent than doxorubicine treatment. Treatment with berberine-induced cell cycle arrest at G0/G1 in the anoikis-resistant MCF-7 and MDA-MB-231 cells as compared to untreated control cells. In summary, these results revealed that berberine can efficiently inhibit growth by inducing cell cycle arrest in anoikis-resistant MCF-7 and MDA-MB-231 cells. Further analysis of these phenotypes is essential for understanding the effect of berberine on anoikis-resistant breast cancer cells, which would be relevant for the therapeutic targeting of breast cancer metastasis.

Usefulness of catheter-directed thrombolysis using alteplase in peripheral vascular occlusion.

This study evaluated the safety and efficacy of alteplase in catheter-directed treatment for peripheral arterial and venous thrombosis and considered the optimal dosing regimen. Forty-four patients (49 encounters) underwent transcatheter therapy using alteplase between January and November 1999. The most common indications for thrombolysis were peripheral arterial occlusion (PAO) and venous thrombosis (38 patients, 43 encounters). Each encounter was reviewed for indication, dosage of alteplase, duration of infusion, concomitant use of anticoagulation, degree of lysis, and complications. Patients were divided into low-dose (0.5 to 1.0 mg/hr), mid-dose (1.0 to 1.5 mg/hr), and high-dose (>1.5 mg/hr) groups. For PAO, there was no significant difference in the success rate between the 3 dose groups. A lower complication rate was achieved in the low-dose group. For venous thrombosis, there was no difference in the overall success or complication rates for each of the 3 groups. Partial lysis was achieved more readily in the mid and high-dose groups, but the risk of serious complications was greater. Overall, the complete thrombolysis rate was 71% for PAO and 55% for venous thrombosis. Major and minor complication rates were 7% and 19%, respectively. An equivalent success rate with a lower complication rate can be achieved using a low-dose constant catheter-directed infusion of alteplase for cases of PAO. Cases of venous thrombosis had a lower overall success rate compared with PAO. A mid-dose infusion of alteplase can achieve greater complete and partial thrombolysis rates without increasing the complication rate. Major and minor complication rates were similar to the rates given in the published literature.

Cloning and expression of the VP2 gene of an infectious bursal disease virus.

A serotype I infectious bursal disease virus (IBDV) strain HZ96 was isolated in Hangzhou, China, in 1996 and attenuated by adaptation to chicken embryo fibroblast cells. The VP2 gene of strain HZ96 was amplified by reverse transcription-polymerase chain reaction, cloned, and sequenced. Compared with the VP2 sequences of other IBDV strains, HZ96 is most related to two attenuated strains, CU-1 and PBG98, and two attenuated Chinese strains, Harbin and CJ801bkf. HZ96 shares nucleotide sequence homology 98.9% with CU-1 and PBG98, 98.5% with Harbin, and 98.6% with CJ801bkf. Most of the sequence variations observed between HZ96 and other strains are located in the middle variable region from nucleotides 637 to 996. Similar to other attenuated IBDVs, HZ96 has unique substitutions at residues 279 (Asp to Asn) and 284 (Ala to Thr), suggesting that these two substitutions may be directly related to adaptation of the virus to cell culture and attenuation of its virulence. As part of our effort to develop a submit vaccine for IBDV, the VP2 gene of HZ96 was cloned into a heat-inducible expression vector and expressed in Escherichia coli system. A protein band with expected molecular weight of 52 kD was detected by direct protein staining and western blotting.

The ureteric ring.

A ureteric ring is a smooth, concentric ring-like narrowing occurring in the upper third of the ureter. It is nonobstructive and may be transient and bilateral. There is a slight female preponderance. They are seen in all age groups and are common in the neonate together with transient changes. A ureteric ring has a characteristic appearance and is believed to result from contraction of circular muscle.