Postoperative chest radiographic changes after on- and off-pump coronary surgery.

AIM: A variety of chest radiograph abnormalities are recognized after coronary artery bypass grafting (CABG). This study analyzes the appearance of preoperative and postoperative chest radiographs in two groups of patients undergoing myocardial revascularization with or without the use of cardiopulmonary bypass (CPB). METHODS: Chest radiographs (preoperative and at 1 day, 6 days and 6 to 8 weeks post operatively) were analyzed according to a detailed protocol in cases of conventional CABG on CPB (n=60) or off-pump coronary artery bypass (OPCAB) (n=60) surgery. On each film 17 different major potential postoperative abnormalities were analyzed. RESULTS: Clinical findings were similar in the two groups. Patients undergoing OPCAB surgery had decreased blood loss, decreased red cell and platelet transfusion, significantly lower intubation time and required less postoperative inotropic support compared with patients undergoing CPB. The CPB group had a significantly higher incidence of left band atelectasis than the OPCAB group (37.6% vs 17.5%, p=0.01) at 6 days postoperatively. There was no other statistically significant difference in any of the 16 remaining major chest radiograph findings between the two groups. CONCLUSION: Although OPCAB surgery is associated with improved clinical outcome compared with conventional CABG surgery, the analysis of postoperative chest radiographs demonstrated only a minor benefit as shown by a reduced degree of left band atelectasis in the OPCAB group.

Effect of copper-containing intrauterine contraceptive devices (IUCD) on growth of endometrial and cervical cells.

PIP: Physicians at the School of Medicine at the University of Baghdad in Iraq took a biopsy of endometrial and cervical tissue from women between 25-40 years old before and after using a copper IUD. Researchers exposed each tissue type to autoradiography using 5% methyl tritiated thymidine to indicate active cell metabolism. They also examined each type with an electron microscope. Thymidine uptake fell as duration of a copper IUD was used. For example, 52% of the endometrial and cervical cells were viable before insertion of the copper IUD. After 5 months, thymidine uptake fell remarkably to 32%. It fell to 20% at 12 months, 10% at 18 months, and 6% at 36 months. The thymidine uptake between endometrial and cervical tissue was not statistically different. The major change in the cervix as observed under electron microscopy included a few to a significant number of lymphocytes between the epithelial cells. Apical protrusions remained the same in the secretory cells of the endothelial lining in the endometrium and the glands. In tissues exposed to a copper IUD, the mitochondria of cells in the lumen and glands swelled and the number of lysosomes increased. Further, the number of lymphocytes also increased in both the cervix and endometrium. These results demonstrate the inhibition of mitotic activity in cervical and endometrial cells brought on by a copper IUD, especially during the 1st 2 months. This action could adversely affect a fetus if pregnancy occurs at this time. The researchers suggest that health practitioners advise any pregnant woman who had only recently got a copper IUD to abort the fetus.^ieng

Effect of phenytoin on mitotic activity of gingival tissue and cultured fibroblasts.

The effect of phenytoin on the mitotic activity of gingival tissue as well as cultured mammalian fibroblasts was studied. This was measured quantitatively using autoradiography utilizing tritiated thymidine. Hyperplastic gingiva removed from patients treated with phenytoin and subjected to autoradiography showed a marked increase in the mitotic activity of gingival cells. This was also the case with cultured fibroblasts. The mitotic index was higher in the treated fibroblasts than that of the control. Ascorbic acid added to the cultures markedly reduced the mitotic activity of these cells. These results agree with other studies that phenytoin may be a factor in direct stimulation of the mitotic activity and gingival hyperplasia seen in patients taking this medication.

The actions of prostaglandins E 1 and F 2 on the on the perfused vessels of the isolated rabbit ear.

1. In the isolated rabbit ear vascular bed, perfused with Krebs solution, prostaglandins E(1) and F(2alpha) produce dose-dependent, phentolamine-sensitive constrictions.2. These are absent if the animal is pre-treated with reserpine or if the ear is denervated in advance.3. If noradrenaline or vasopressin is added to the Krebs solution, vascular resistance is high and PGE(1) and PGF(2alpha) produce vasodilatation which is unaffected by hyoscine or propranolol.4. Perfusion with theophylline, with added ATP, ADP or 3'5'-AMP, or pre-treatment of the animal with stilboestrol antagonizes the dilator response to PGE(1) in the presence of noradrenaline, which may be reversed. Most of the responses to PGF(2alpha) are reversed. These treatments elevate the level of 3'5'-AMP in tissues.5. It is postulated that prostaglandins exert a regulatory action on 3'5'-AMP levels through inhibition of adenyl cyclase and/or phosphodiesterase and that the resulting rising or falling level of 3'5'-AMP determines the nature of the response by the smooth muscle to the released noradrenaline.