Use of a dual lumen port for automated red cell exchange in adults with sickle cell disease

Red cell exchange (RCE) is a common procedure in adults with sickle cell disease (SCD). Implantable dual lumen Vortex (DLV) ports can be used for RCE in patients with poor peripheral venous access. We performed a retrospective cohort study of RCE procedures performed in adults with SCD. The main objective of the study was to compare the inlet speed, duration of procedures and rate of complications performed through DLV ports to those performed through temporary central venous and peripheral catheters. Twenty‐nine adults with SCD underwent a total of 318 RCE procedures. Twenty adults had DLV ports placed and 218 procedures were performed using DLV ports. Mean length of follow‐up after DLV port placement was 397 ± 263 days. Six DLV ports were removed due to infection and 1 for malfunction after a mean of 171 ± 120 days. Compared to temporary central venous and peripheral catheters, DLV port procedures had a greater rate of procedural complications, a longer duration, and a lower inlet speed (all P < 0.01). When accounting for the maximum allowable inlet speed to avoid citrate toxicity, 40% of DLV port procedures were greater than 10% below maximum speed, compared to 7 and 14% of procedures performed through temporary central venous and peripheral catheters (P < 0.0001). In conclusion, DLV ports can be used for RCE in adults with SCD, albeit with more procedural complications and longer duration. The smaller internal diameter and longer catheter of DLV ports compared to temporary central venous catheters likely accounts for the differences noted. J. Clin. Apheresis 30:353–358, 2015. © 2015 Wiley Periodicals, Inc.     

Regulated expression of the IL-31 receptor in bronchial and alveolar epithelial cells, pulmonary fibroblasts, and pulmonary macrophages.

Interleukin-31 (IL-31), an IL-6 cytokine family member, is proposed to play a role in animal models of airway hyperreactivity. It is produced by activated T cells and signals via a heterodimeric receptor complex composed of IL-31Ralpha and OSMRbeta. Only low levels of IL-31Ralpha expression have been demonstrated in pulmonary epithelial cell lines, however, and little is known about the ability to regulate its expression and signaling. Therefore, primary cultures of human bronchial and alveolar epithelial cells, pulmonary fibroblasts, pulmonary macrophages, and established lines of immortalized bronchial epithelial cells (HBE) and alveolar carcinoma cells (A549) were analyzed by RT-PCR, immunoblotting, and thymidine incorporation. Distinct, cell type-specific regulation of IL-31Ralpha expression was detected. Transforming growth factor-beta (TGF-beta) enhanced IL-31Ralpha mRNA expression in primary cultures and established lines of epithelial cells, but not in macrophages. In contrast, interferon-gamma (IFN-gamma) induced IL-31Ralpha mRNA expression in macrophages. IL-31Ralpha protein expression was below detection threshold in primary epithelial cell cultures but was detectable in A549 cells and increased with TGF-beta treatment. In HBE and A549 cells, TGF-beta pretreatment increased IL-31-mediated Stat3 and extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation. In A549 cells, TGF-beta magnified IL-31-dependent suppression of proliferation. The data suggest that increased IL-31Ralpha expression correlates with an enhanced response to IL-31.     

Identification of amino acid residues of anthrax protective antigen involved in binding with lethal factor

Protective antigen (PA) and lethal factor (LF) are the two components of anthrax lethal toxin. PA is responsible for the translocation of LF to the cytosol. The binding of LF to cell surface receptor-bound PA is a prerequisite for the formation of lethal toxin. It has been hypothesized that hydrophobic residues P184, L187, F202, L203, P205, I207, I210, W226, and F236 of domain 1b of PA play an important role in the binding of PA to LF. These residues are normally buried in the 83-kDA version of PA, PA83, as determined by the crystal structure of PA. However, they become exposed due to the conformational change brought about by the cleavage of PA83 to PA63 by a cell surface protease. Mutation of the above-mentioned residues to alanine resulted in mutant proteins that were able to bind to the cell surface receptors and also to be specifically cleaved by the cellular proteases. All the mutant proteins except the F202A, L203A, P205A, and I207A mutants were able to bind to LF and were also toxic to macrophage cells in combination with LF. It was concluded that residues 202, 203, 205, and 207 of PA are essential for the binding of LF to PA.     

Prostaglandin E2 synthesis and suppression of fibroblast proliferation by alveolar epithelial cells is cyclooxygenase-2-dependent

Alveolar epithelial cells (AECs) may influence neighboring fibroblasts by the elaboration of prostaglandin E(2) (PGE(2)). This prostanoid can be synthesized via "constitutive" cyclooxygenase (COX)-1 and "inducible" COX-2 enzyme isoforms. We compared AECs isolated from wild-type (WT), COX-1 knockout (KO), and COX-2 KO mice to determine the contribution of COX isoforms to AEC PGE(2) synthesis and capacity for suppression of fibroblast proliferation in co-cultures. WT AECs constitutively expressed both COX-1 and COX-2 isoforms by immunoblot analysis. COX-1 KO cells and WT cells comparably augmented PGE(2) synthesis following incubation with lipopolysaccharide or interleukin-1, whereas COX-2 KO cells were unable to do so. Surprisingly, however, constitutive generation of PGE(2) was also dramatically reduced only in COX-2 KO cells. When co-cultured with WT murine lung fibroblasts, AECs from WT and COX-1 KO animals suppressed serum-induced fibroblast proliferation, whereas COX-2-deficient AECs caused a modest enhancement in fibroblast proliferation. These results indicate that PGE(2) synthetic capacity in AECs is predominantly COX-2-dependent under both basal and stimulated conditions. They also demonstrate conclusively that AECs can modulate fibroblast function by the elaboration of suppressive prostanoids. These alterations in AEC phenotype likely contribute to the propensity for pulmonary fibrosis observed in COX-2-deficient mice.     

Physiologic Transdermal Estradiol Replacement Mimics Effects of Endogenous Estrogen on Bone Outcomes in Hypoestrogenic Women with Anorexia Nervosa

Background: While physiologic estrogen replacement results in increases in areal bone mineral density (aBMD) in hypoestrogenic adolescent girls and young adult women with AN, data are lacking regarding its impact on measures of volumetric BMD (vBMD), bone geometry, and structure. Methods: 23 young women with anorexia nervosa (AN) and 27 normal-weight healthy controls (HC) between 14–25 years old were followed for 12 months. AN participants received transdermal 17β-estradiol (continuously) with 10 days of cyclic oral progesterone (100 mg daily) every month for the study duration (AN-E+). DXA was used to measure aBMD and body composition, high resolution peripheral quantitative CT (HRpQCT) to assess vBMD, bone geometry and structure at the distal radius and tibia, and microfinite element analysis to estimate strength. Results: Groups did not differ for age. Median baseline BMI z-scores were −1.13 (−1.58, −0.38) in AN-E+ vs. 0.08 (−0.40, 0.84) in HC (p < 0.0001). For most HRpQCT parameters and strength estimates, young women with AN receiving physiologic estrogen replacement demonstrated similar changes over 12 months as did normoestrogenic HC. Additionally, radial cortical tissue mineral density, cortical vBMD, and failure load increased (p = 0.01; p = 0.02; p = 0.004 respectively) over 12 months in AN-E+ compared to HC. Conclusions: With physiologic estrogen replacement, bone accrual improved in AN to approximate changes observed in normoestrogenic controls followed without any intervention, with additional benefits observed for cortical tissue mineral density, cortical vBMD, and failure load at the radius in AN vs. controls. Thus, this strategy for estrogen replacement effectively mimics the effects of endogenous estrogen on bone structure and estimated strength.     

Mucinous cystadenocarcinoma arising in mature cystic teratoma ovary and associated pseudomyxoma peritonei: report of a case

Pseudomyxoma peritonei (PMP) is most commonly associated with intra-abdominal spread of an appendiceal mucinous neoplasm and very rarely seen in cases of primary ovarian tumours. Mucinous adenocarcinoma arising in a mature cystic teratoma giving rise to PMP is even rarer. Extensive medlar search has revealed only nine cases; we are reporting tenth such case.     

Proton pump inhibitor use and risk for recurrent Clostridioides difficile infection: a systematic review and meta-analysis

ObjectivesProton pump inhibitor (PPI) therapy is a potentially modifiable risk factor for recurrent Clostridioides difficile infection (CDI). Citing an absence of clinical trials, many guidelines do not provide recommendations for addressing PPI management. Our aim was to perform an updated systematic review and meta-analysis evaluating the association between PPI use and recurrent CDI addressing prior methodological limitations.MethodsData sources were MEDLINE and EMBASE. Eligible studies were cohort and case–control studies; there were no restrictions on study setting or duration of follow-up. Participants were adults with prior CDI who did or did not receive PPI therapy and were assessed for recurrent CDI. Summary (unadjusted) odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using a random effects model. Prespecified subgroup analyses were performed to explore heterogeneity including study design, study quality, duration of follow-up, adjustment for confounders, and outcome definition.ResultsSixteen studies were included in the meta-analysis, comprising 57 477 patients with CDI, of whom 6870 (12%) received PPIs. The rate of recurrent CDI was 24% in patients treated with PPIs versus 18% in those who were not. A meta-analysis that pooled unadjusted odds ratios demonstrated higher odds of recurrent CDI in patients who received PPIs (OR 1.69, 95%CI 1.46–1.96) versus those who did not. There was moderate heterogeneity between studies (I² 56%); however, a sensitivity analysis restricted to studies with 56 days of follow-up substantially reduced the heterogeneity (OR 1.59, 95%CI 1.36–1.85; I² 12%). An analysis restricted to multivariate studies that combined adjusted ORs also demonstrated higher odds of recurrent CDI in patients who received PPIs (OR 1.49, 95%CI 1.12–2.00). No publication bias was identified.ConclusionsWe found significantly higher odds of recurrent CDI among users of PPIs that persisted across multiple sensitivity analyses. These results support stronger recommendations for PPI stewardship at CDI diagnosis.     

Urgent Redo-Laparotomies: Patterns and Outcome—A Single Centre Experience

A proportion of the operations performed in a surgical gastroenterology department are unplanned repeat laparotomies for complications of the original procedure. We examined why, in our department, these ‘redo’ laparotomies were performed and what was their outcome. We retrospectively analyzed 6530 patients operated between September 1996 - December 2010, of these 257 redo laparotomies were performed in 193(2.5 %) patients. There were 138 males and 55 females who had a mean age of 42 years (range 7–68 years). Eighty one (42 %) of the index surgeries were elective and 112 (58 %) performed in the emergency situation. Pancreas was the commonest organ for the index operation {50 (25.9 %)}, followed by the colon and rectum {45 (23.3 %)} and the small bowel {36 (18.7 %)}. Postoperative bleeding was the most common cause for re-exploration 66 (34.2 %) followed by an abscess or fluid collection that required surgical drainage 57 (29.6 %). The mortality rate after redo laparotomies was 33.2 % with sepsis and multi-organ failure being the commonest cause of death. Urgent redo-laparotomies that are performed following complicated abdominal operations have a high mortality rate. Postoperative bleeding, intrabdominal abscess and peritonitis are the commonest cause for redo-laparotomy. Multiple redolaparotomies and associated co-morbid conditions are significant predictors of mortality.