Conversion of temporary hemodialysis catheters to tunneled hemodialysis catheters

PURPOSE: To determine the feasibility and clinical outcomes of conversion of temporary to tunneled hemodialysis catheters using the same venous insertion site. METHODS: Data from 42 patients with existing temporary hemodialysis catheters referred for placement of tunneled hemodialysis catheters were retrospectively reviewed. In these patients, the temporary catheter was exchanged for a peel-away sheath, and a tunneled catheter was inserted using the existing venous access site. Technical success, procedural complications, and clinical outcomes were evaluated. Hemodialysis records were reviewed to assess catheter patency during a 30-day follow-up period. RESULTS: The study group consisted of 20 males and 22 females (mean age: 58 years). All 42 temporary catheters were successfully converted to tunneled hemodialysis catheters without immediate procedure-related complications. Follow-up data were available for 32 patients (total: 3038; median 71 catheter days). Nine catheters were removed for infection, yielding a catheter infection rate of 0.30/100 catheter days; three catheters were removed for blood flow <200 ml/min. 13 patients had catheters removed when catheters were no longer needed. Three patients died with working catheters. The patency rate was 72% at 30 days, with four catheters functioning at the end of the study period. CONCLUSION: Conversion of a temporary hemodialysis catheter to a tunneled hemodialysis catheter using the same venous insertion site is a safe procedure that avoids complications associated with venotomy and allows conservation of other central venous access sites. Patency and infection rates in these catheters are comparable to several studies of catheter exchange and de novo placement of tunneled hemodialysis catheters.     

Lysophosphatidic acid induces glycodelin gene expression in cancer cells

Glycodelin is a glycoprotein that has been suggested to be important in normal pregnancy and in malignancy. The regulation of its synthesis has not been studied. In this study, we report the induction of glycodelin gene expression by lysophosphatidic acid (LPA). We studied the effect of LPA (5, 10 and 25 microM) on glycodelin production in breast (MDA-MB-231), cervical (Hela), endometrial (RL-95), ovarian cancer (OVCAR-3) and erythroleukemia (K562) cells. There was a dose-dependent (5-25 microM) induction of glycodelin gene and protein expression in these cell types. LPA is a mimic of phorbol myristate acetate (PMA) action and is found to be elevated in high concentrations in the serum of cancer subjects. As glycodelin is an angiogenic protein with a potential immunosuppressive role, control of LPA synthesis might offer a potential target for intervention.     

Invasive aspergillosis in cancer

Ten confirmed cases of invasive aspergillosis (IA) in cancer patients were analysed retrospectively. Eight were pulmonary, one was sinonasal and one was cutaneous. The majority of patients had haematological malignancies (7), the remaining three were cases of solid tumours. Fever was present in all 10 cases. Cough and lung signs were present in all eight cases of invasive pulmonary aspergillosis. Haemoptysis was encountered in three of nine cases of pulmonary and sinonasal aspergillosis. Mortality was low (2%). While corticosteroids, antibiotics and anticancer chemotherapy/radiotherapy were factors predisposing the patients to IA, neutropenia was perhaps responsible for their mortality. Seven of the patients had other associated pathogens isolated in culture in addition to Aspergillus spp. Aspergillus fumigatus was the predominant species, followed by A. flavus, A. glaucus, A. nidulans and A. niger. Direct microscopic examination (in six of seven cases) and culture (six of seven cases) correlated well with radiographic and clinical findings in cases with lung involvement. Serology for anti-Aspergillus antibodies performed by gel diffusion precipitin test was positive in one case of sinonasal aspergillosis, wherein only one precipitin band was observed. Correlation of clinical symptoms, consistent radiographic findings and microbiological work-up (the latter including a triad of direct microscopy, culture and serology) are required to arrive at a diagnosis of IA, especially where histology cannot form the mainstay of diagnosis.     

Conversion of temporary hemodialysis catheters to permanent hemodialysis catheters: a retrospective study of catheter exchange versus classic de novo placement

Many clinicians believe that de novo access is required when converting temporary hemodialysis (HD) catheters to long-term or permanent catheters. However, since vascular access sites are at a premium in the dialysis patient, it is important to preserve existing central venous catheters and conserve future access sites. In this retrospective study, data from 94 patients referred to interventional radiology for placement of long-term, tunneled HD catheters between July 2001 and September 2002 were reviewed. The study group consisted of 42 patients in whom the temporary catheter was exchanged for a peel-away sheath and a tunneled catheter inserted using the existing venous access site. The control group included 52 patients who received traditional de novo placement of permanent catheters. Based on available follow-up data, we report a 100% technical success rate, with 72% patency at 30 days in the study group (n = 32; mean age 58 years). By comparison, de novo catheter placement (n = 35; mean age 59 years) yielded a 100% technical success rate, with 83% patency at 30 days. The overall infection rate was 0.30 per 100 catheter-days (total 3036 catheter-days) and 0.36 per 100 catheter-days (total 3295 catheter-days), respectively (chi2 = 0.64, p > or = 0.05). There was no incidence of exit site infection, tunnel infection, or florid sepsis in either group. Likewise, no stenosis or bleeding complication was noted. Thus conversion of a temporary HD catheter to a tunneled catheter using the same venous insertion site is safe, does not increase the risk of infection, and allows conservation of other central venous access sites.     

Vitamins E and C are safe across a broad range of intakes

A robust database shows that dietary supplements of vitamins E and C are safe for the general population. Because these nutrients supply antioxidant and other functions for homeostasis and protection against free radical damage, supplementation has been intensively studied. Because of perceived benefits, many persons consume quantities of vitamins E and C well above the recommended dietary allowances. As safety guidance, tolerable upper intake levels have been established by the Food and Nutrition Board, Institute of Medicine, at 1000 mg for vitamin E and 2000 mg for vitamin C in adults. Many clinical trials with these vitamins have involved subjects with various diseases, and no consistent pattern of adverse effects has occurred at any intake. Numerous studies of vitamin C supplementation have provided no pattern of evidence to support concerns about safety other than occasional gastrointestinal upset or mild diarrhea resulting from the osmotic effects of unabsorbed quantities of vitamin C. Evidence of bleeding effects and other potential adverse effects of high vitamin E intakes in humans is not convincing. Evidence of adverse effects of vitamin C that result from its effects on iron absorption and metabolism has not been confirmed in clinical trials. Thus, we conclude from clinical trial evidence that vitamin E supplements appear safe for most adults in amounts 相似文献   

Similarities and differences in distortion-product otoacoustic emissions among four FDA-approved devices

Similarities and differences in distortion-product otoacoustic emissions (DPOAEs) among four Food and Drug Administration (FDA) approved devices were assessed quantitatively. DPOAEs were recorded from 42 adult subjects (84 ears) ranging in age from 19 to 40 years. All subjects had hearing thresholds of 20 dB HL or better for the test frequencies from 0.25 to 8.0 kHz and normal acoustic immittance findings. DPOAEs were collected in a quiet non-sound-treated room. DPOAE measurement parameters included an f2/f1 ratio of approximately 1.2, with f1 at 65 dB SPL (L1) and f2 at 55 dB SPL (L2). There were no significant differences in the mean emissions levels among the four devices. This investigation showed that validity criteria, pass criteria, and strategies for DPOAE measurements interact to produce varying pass and refer results. However, when DPOAEs are obtained with consistent validity criteria, pass criteria, and strategies for measurement, the results are remarkably consistent.     

RU486-induced growth inhibition of human endometrial cells

OBJECTIVE: To determine the direct action of RU486 on endometrial cell proliferation and to differentiate whether the antioxidant or the antiprogesterone property of RU486 is predominately responsible for its effect on cell growth. DESIGN: In vitro study comparing the effects of RU486 (antiprogesterone and antioxidant), reduced RU486 (antioxidant), ZK112,993 (antiprogesterone), and lazaroid U74,500A (antioxidant) on endometrial cell growth. The human endometrial cell line EM42 was used in transient transfection assays to confirm the relative antiprogesterone potency of the various compounds. SETTING: Academic medical center PATIENT(S): Women presenting with pelvic pain or infertility and diagnosed with endometriosis at time of surgery or women desiring tubal ligation with a normal pelvis (controls). INTERVENTION(S): Endometrial cell cultures were treated with RU486, reduced RU486, lazaroid U74,500A, and ZK112,993. MAIN OUTCOME MEASURE(S): Tritiated thymidine incorporation was used to assess cell growth. Inhibition of progesterone induction of transiently transfected reporter plasmids was used to measure antiprogesterone activity of compounds studied. RESULT(S): RU486 reduced cell growth in a dose-dependent fashion of the endometrial cell lines EM42 and RL95-2 and of endometrial and endometriosis cells from primary culture. After being reduced, RU486 lost most of its antiprogesterone activity but retained its antiproliferative properties. ZK112,993 was similar in potency to RU486 as a progesterone antagonist but did not significantly modify endometrial cell growth. Lazaroid U74,500A was devoid of antiprogesterone activity but was shown to be a potent antiproliferative agent. CONCLUSION(S): RU486 has a direct inhibitory effect on human endometrial cell growth. This activity appears to be at least partly mediated through its antioxidant property.     

Implications in the maintenance of pregnancy: I. Presence of immunoreactive glycodelin in human umbilical cord vein endothelial cells

OBJECTIVE: We previously reported an antipeptide antibody to human glycodelin that recognizes glycodelin in amniotic fluid and epithelial glands of the endometrium. The objective of this study was to determine the presence of glycodelin in human umbilical cord. DESIGN: Controlled clinical study. SETTING: Healthy women undergoing normal delivery at Grady Memorial Hospital, Atlanta, Georgia. PATIENT(s): Healthy women undergoing normal delivery. Intervention(s): None. MAIN OUTCOME MEASURE(s): Umbilical cord vein was isolated from the cord and used for immunohistochemical studies. Human umbilical cords and placentae were collected after full-term delivery. Cords were washed and fixed with formal sucrose. Decidua tissues and blood vessels from placentae were dissected out and fixed. Cryostat sections were immunostained with anti-glycodelin peptide antibody and anti-von Willebrand factor antibody. RESULT(s): Endothelial cells of human umbilical cord vein and artery were strongly immunostained with antiglycodelin antibody. Endothelial cells of the vein were more strongly stained than those of the artery. These cells were confirmed as endothelial cells by positive immunostaining with anti-von Willebrand factor. The epithelial cells outlining the cord were stained with antiglycodelin antibody but not with anti-von Willebrand factor antibody. CONCLUSION(s): This is the first study showing that immunoreactive glycodelin is present in endothelial cells of the umbilical cord. Glycodelin in the umbilical cord may have immunosuppressive or other, unknown functions affecting the physiology or pathophysiology of pregnancy. Whether umbilical vein endothelial cells synthesize glycodelin or serve as reservoir for glycodelin is currently under investigation.