Trans-scleral application of a semiconductor diode laser

We used a diode laser with an output power of 1 W through a fiberoptic light pipe (200 microns diameter) to deliver laser energy through the sclera of pigmented rabbits. Ciliary body destruction occurred with energy levels of 300-400 mW and exposure time of 0.5 sec. Retinal photocoagulation was achieved with energy levels of 200-500 mW in 0.5 sec. Histologic examination of acute lesions demonstrated thermal destruction of ciliary body processes and retina. Chorioretinal scar formation was observed clinically and histologically within 2-3 weeks. Our data indicate that the transscleral diode laser may be used for destruction of the ciliary body processes or peripheral retinal coagulation in pigmented eyes.     

Accelerated reversal of atracurium blockade with divided doses of neostigmine

The hypothesis that administration of neostigmine in divided doses might accelerate the antagonism of neuromuscular blockade was investigated. Neostigmine 0.05 mg X kg-1 was administered either in a single bolus dose (Group I, n = 16) or in an initial dose of 0.01 mg X kg-1 followed three minutes later by 0.04 mg X kg-1 (Group II, n = 16) for antagonism of atracurium-induced blockade. Reversal was attempted at 10 per cent spontaneous recovery of twitch height. The mean time (+/- SD) from the first injection of the drug until the train-of-four (TOF) ratio value had reached 0.75 was significantly shorter in Group II (p less than 0.05) than in Group I (391.8 +/- 83.3 and 468.6 +/- 150.3 seconds respectively). The rate of TOF ratio recovery was 2.5 times faster after neostigmine administration in divided doses. It is concluded that administration of neostigmine in divided doses, as described in this study, produced a significantly faster reversal of residual atracurium-induced neuromuscular blockade as compared to a single bolus administration.     

Intraoperative blood loss is a risk factor for complications in donors after living donor hepatectomy.

Complications in a donor are a distressing but inevitable occurrence, since graft procurement is a major undertaking. Although the technique for procurement has some similarities to hepatic resection, a donor is very unlike a patient with malignancy. The risk factors identified in these patients cannot be extrapolated to donors. Donor hepatectomy carried out from June 1995 to March 2005 in Chang Gung Memorial Hospital, Kaohsiung Medical Center was reviewed with the aim of identifying risk factors for complications. There were 204 living donor liver transplants, with 205 donor hepatectomies, as 1 living donor liver transplantation was a dual graft. Ten donors (4.88%) suffered complications. There was no difference in terms of age, gender, body weight, operation, and parenchymal time between those who had complications and those who did not. There was also no difference in liver function tests between the 2 groups of donors, but the total bilirubin was significantly higher in donors with complications. The graft weight and remnant liver volume were also similar. The proportion of donors with fatty liver was the same between the 2 groups. The mean blood loss in donors with complications was 170 +/- 79 mL, and that for donors without complications was 95 +/- 77 mL. There was a statistically significant greater blood loss in donors with complications (P < 0.05). The number of segments removed in donors with complications was also higher compared to donors without complications (P < 0.03). Using multivariate analysis, intraoperative blood loss and the number of segments removed were found to be independent risk factors for donor complications. Intraoperative blood loss during graft procurement must be kept low to minimize complications in donors.     

Cystic fibrosis detection in high-risk Egyptian children and CFTR mutation analysis.

BACKGROUND: Knowledge about Cystic Fibrosis (CF) in Egypt is very limited. The objective of this study was to screen for CF in Egyptian children with suggestive clinical features and to identify causative genetic mutations. METHODS: Sixty-one patients from the Chest Unit, Cairo University Children's Hospital, Egypt, were included. Subjects presented with persistent or recurrent respiratory symptoms, failure to thrive, diarrhea and/or steatorrhea and unexplained persistent jaundice. Patients were screened using the CF Indicatortrade mark sweat test system (PolyChrome Medical, Inc., Brooklyn Center, MN). A quantitative sweat testing was conducted on 10 of the 12 positive patients. Seven probands and one sibling underwent molecular analysis by direct DNA sequencing of the coding region and of the intronic sequences adjacent to the 27 exons of the CFTR gene. RESULTS: Of 61 patients, 12 (20%) had positive sweat chloride screening. Ten of the 12 patients underwent quantitative sweat testing and were positive. Eight CFTR sequence changes were identified in seven affected probands and two were confirmed in one sibling by direct DNA sequencing. CONCLUSION: The study results suggest that CF is more common in Egypt than previously anticipated. Larger studies are warranted to identify the incidence, molecular basis and clinical pattern of CF in the Egyptian population.     

Comparative study of three fluorescent dyes for angiography: sodium fluorescein, carboxyfluorescein, and calcein

To compare the characteristics of carboxyfluorescein (CF) and calcein (Calc) with those of sodium fluorescein (Naf), the only fluorescent dye currently in clinical use, we performed angiography in rabbits and primates using these three dyes. The circulation decay time of all dyes was longer in primates than in rabbits. In primates, CF and Calc had longer decay times than Naf. Calc produced the greatest contrast between the choroidal and retinal vasculature. Tissue staining and dye leakage into the vitreous immediately after retinal photocoagulation were minimal with Calc, moderate with CF, and marked with Naf. The limited leakage and longer circulation time of Calc may permit simultaneous angiography and photocoagulation therapy without obscuring the fundus view with leaking dye from the photocoagulated structure.     

Antitumor activity and pharmacokinetics following oral administration of natural product DNA topoisomerase I inhibitors 10-hydroxycamptothecin and camptothecin in SCID mice bearing human breast cancer xenografts

The DNA topoisomerase I inhibitors, 10-hydroxycamptothecin (HCPT) and camptothecin (CPT), are indole alkaloids isolated from the Chinese tree, Camptotheca acuminata. They have been shown to have a wide spectrum of anticancer activity both in vitro and in vivo. However, their use has been limited due to their water-insolubility. The purpose of the present study was 2-fold, to determine the in vitro and in vivo activity of HCPT and CPT against human breast cancer and to determine the pharmacokinetics of the two drugs to better understand how they can best be used therapeutically. The bl vitro inhibitory effect on tumor growth was observed with breast cancer cell line MDA-MB-468. The in vivo antitumor effects were then determined using severe combined immunodeficient (SCID) mice bearing MDA-MB-468 xenografts. The tumor-bearing mice were orally administered HCPT (1, 3, 6, 9 mg/kg/day, 5 days per week) or CPT (1, 3, 6 mg/kg/day, 5 days per week) for 3 weeks. Growth of the MDA-MB-468 cells was inhibited by HCPT and CPT in vitro and in vivo in a dose-dependent manner. Complete regression of the tumor xenografts, determined by tumor measurement and microscopic examination, occurred in the groups of animals treated with doses of HCPT or CPT of 3 mg/kg/day or more. In general, HCPT was more effective and less toxic than CPT. To determine the potential mechanisms for the pharmacologic differences, the comparative pharmacokinetics of HCPT and CPT were determined in tumor-bearing SCID mice following i.v. or oral administration of H-3-HCPT or H-3-CPT. Parent drugs and their metabolites in plasma, urine, feces, and various tissues were quantified by a recently developed reversed-phase HPLC method. Significant absorption of both HCPT and CPT was observed after oral administration, with CPT having a higher bioavailability. HCPT and CPT were distributed widely into various tissues including the tumor, enterohepatic system, kidneys, and bone marrow. These studies indicate that HCPT and CPT are of potential use in treatment of breast cancer, providing the basis for the design of future human trials with these anticancer drugs.     

Edrophonium priming alters the course of neuromuscular recovery from a pipecuronium neuromuscular blockade

This study was designed to investigate the effect of divided administration of edrophonium on the course of neuromuscular recovery from a pipecuronium neuromuscular blockade. During thiopentone-nitrous oxide-halothane anaesthesia 48 patients were given pipecuronium 70 micrograms.kg-1. Patients were randomly assigned to one of four groups (n = 12 in each) to receive either edrophonium 1 mg.kg-1 (Groups I and II) or edrophonium 0.75 mg.kg-1 (Groups III and IV). In Groups I and III (single-dose groups), edrophonium was administered as a single bolus dose. In Groups II and IV (divided-dose groups) edrophonium was administered as an initial dose of 0.25 mg.kg-1 followed three minutes later by either 0.75 or 0.50 mg.kg-1 respectively. Reversal was attempted at 20% spontaneous recovery of twitch height. Administration of edrophonium in divided doses (Groups II and IV) accelerated the reversal of the pipecuronium neuromuscular blockade. At ten minutes post-reversal, train-of-four (TOF) ratio recovery reached 0.75 or more in 12 (100%) and in ten (83%) patients in Groups II and IV respectively. Similarly, times to attain a TOF of 0.75 (SEM) were shorter in the divided-dose groups than in the single-dose groups (P less than 0.05), being 354.5 (38.7) and 398.3 (49.1) sec in Groups II and IV vs 705.4 (66.6) and 651.2 (54.3) sec in Groups I and III respectively. Time was counted from the first administration of edrophonium. It is concluded that administration of edrophonium in divided doses produced a faster reversal of residual pipecuronium-induced neuromuscular blockade than single bolus administration. Also, administration in divided doses reduced the requirements of edrophonium needed for reversal of pipecuronium neuromuscular blockade.     

Prognostic value of certain enzymatic and hormonal assays in threatened abortion

The following biochemical indices were evaluated comparatively as predictors of the course of threatened abortion: serum oxytocinase, heat stable alkaline phosphatase, leucine aminopeptidase, urinary pregnanediol, and urinary estriol. 36 cases, grouped into controls and pathological cases, were studied. In normal pregnancy, there was a progressive rise in the levels of the serum oxytocinase, leucine aminopeptidase, urinary estriol, and pregnanediol. Serum heat stable alkaline phosphatase showed an undifferentiated range of results in nonthreatened pregnancies. In the group of threatened abortion cases, results were, therefore, considered abnormal if 2 or more successive determinations showed progressive reduction in enzyme or hormonal levels, and abnormality was also diagnosed if the results were below the normal range (published tabularly, per gestational week). The prognostic value of these biochemical indices was as follows: of 16 cases with normal serum oxytocinase values, 31.2% aborted, whereas of 10 with abnormal values, 70% aborted. Of 16 cases with serum leucine normal values, 37.5% aborted, whereas Of 10 abnormal cases, 60% aborted. Of 18 cases with normal heat stable alkaline phosphatase values, 55.5% aborted, whereas of 8 cases with abnormal values, 25% aborted. Of 17 cases with normal urinary estriol determinations, 45% aborted, whereas of 9 cases with abnormal values, 44.5% aborted. And of 17 cases with normal pregnanediol levels, 41% aborted, whereas of 9 cases with abnormal values, 55.5% aborted. These results show that combined estimation of serum oxytocinase and urinary pregnanediol is a reliable parameter in anticipating pregnancy outcome in cases of threatened abortion.