Hydrogen sulfide promotes migration of trophoblast cells by a Rho GTPase mediated actin cytoskeleton reorganization.

INTRODUCTION: Preeclampsia (PE) arises due to defective spiral artery remodelling which may be due to deficient migration of trophoblast cells. Migration of human endothelial cells has been shown to be promoted via Hydrogen sulphide(H2S)/Rho GTPase Rac1 axis. This novel role of H2S and its downstream processes have not yet been studied in the development and function of the placental trophoblast cells. METHODS: Placental tissues were obtained post-delivery from consented preeclamptic and normotensive mothers (n = 60). The protein expression levels of cystathionine-gamma-lyase (CSE) and cystathionine-beta-synthase (CBS) along with its downstream migratory molecules were compared in both the arms. The pro-migratory role of H2S was investigated in a first trimester placental cell line. RESULTS: H2S promoted the migration of trophoblast cells in a Rho GTPase dependent manner mediated by actin cytoskeleton reorganization. The reduced levels of H2S producing enzymes in the PE placentae along with decreased levels of Rho GTPases (Rac1 and Rho A) corroborate the results of PAG and AOAA treatment in down regulating the Rho GTPases in the in vitro grown placental cultures. Reduction of the migratory potential of trophoblastic cells caused due to hypoxia/reoxygenation was rescued by upregulating the H2S expression with the use of NaHS as a H2S donor. DISCUSSION: Exogenous H2S increases the migratory potential of the placental cells in culture conditions and also post hypoxia/reoxygenation injury. H2S as a gaso-transmitter holds a great potential as a therapeutic agent. Its long-term effects need to be investigated using model systems (rat/mouse) of PE following it up with clinical regulatory trials.

Writing Practices Associated With Electronic Progress Notes and the Preferences of Those Who Read Them: Descriptive Study.

BACKGROUND: Hospital progress notes can serve as an important communication tool. However, they are criticized for their length, preserved content, and for the time physicians spend writing them. OBJECTIVE: We aimed to describe hospital progress note content, writing and reading practices, and the preferences of those who create and read them prior to the implementation of a new electronic health record system. METHODS: Using a sample of hospital progress notes from 1000 randomly selected admissions, we measured note length, similarity of content in successive daily notes for the same patient, the time notes were signed and read, and who read them. We conducted focus group sessions with note writers, readers, and clinical leaders to understand their preferences. RESULTS: We analyzed 4938 inpatient progress notes from 418 authors. The average length was 886 words, and most were in the Assessment & Plan note section. A total of 29% of notes (n=1432) were signed after 4 PM. Notes signed later in the day were read less often. Notes were highly similar from one day to the next, and 26% (23/88) had clinical risk associated with the preserved content. Note content of the highest value varied according to the reader's professional role. CONCLUSIONS: Progress note length varied widely. Notes were often signed late in the day when they were read less often and were highly similar to the note from the previous day. Measuring note length, signing time, when and by whom notes are read, and the amount and safety of preserved content will be useful metrics for measuring how the new electronic health record system is used, and can aid improvements.

Regulation of metastasis suppressor NME1 by a key metabolic cofactor coenzyme A.

The metastasis suppressor protein NME1 is an evolutionarily conserved and multifunctional enzyme that plays an important role in suppressing the invasion and metastasis of tumour cells. The nucleoside diphosphate kinase (NDPK) activity of NME1 is well recognized in balancing the intracellular pools of nucleotide diphosphates and triphosphates to regulate cytoskeletal rearrangement and cell motility, endocytosis, intracellular trafficking, and metastasis. In addition, NME1 was found to function as a protein-histidine kinase, 3'-5' exonuclease and geranyl/farnesyl pyrophosphate kinase. These diverse cellular functions are regulated at the level of expression, post-translational modifications, and regulatory interactions. The NDPK activity of NME1 has been shown to be inhibited in vitro and in vivo under oxidative stress, and the inhibitory effect mediated via redox-sensitive cysteine residues. In this study, affinity purification followed by mass spectrometric analysis revealed NME1 to be a major coenzyme A (CoA) binding protein in cultured cells and rat tissues. NME1 is also found covalently modified by CoA (CoAlation) at Cys109 in the CoAlome analysis of HEK293/Pank1ß cells treated with the disulfide-stress inducer, diamide. Further analysis showed that recombinant NME1 is efficiently CoAlated in vitro and in cellular response to oxidising agents and metabolic stress. In vitro CoAlation of recombinant wild type NME1, but not the C109A mutant, results in the inhibition of its NDPK activity. Moreover, CoA also functions as a competitive inhibitor of the NME1 NDPK activity by binding non-covalently to the nucleotide binding site. Taken together, our data reveal metastasis suppressor protein NME1 as a novel binding partner of the key metabolic regulator CoA, which inhibits its nucleoside diphosphate kinase activity via non-covalent and covalent interactions.

Status of VEGF in preeclampsia and its effect on endoplasmic reticulum stress in placental trophoblast cells.

OBJECTIVE: To explore the role of VEGF in attenuating endoplasmic reticulum stress in placental trophoblast cells. STUDY DESIGN: Study was divided into following parts: 1. Serum Analysis of GRP78 and VEGF using sandwich ELISA. 2. Expression of VEGF and GRP78 in placentae by immunohistochemistry (IHC). 3. In Vitro experiments. Status of ER stress markers (GRP78, eIF2α, XBP1, ATF6 and CHOP) was assessed at various time points (8 h, 14 h, 24 h) when trophoblast cells were treated with varying concentration(s) of VEGF and also by adding recombinant VEGF at protein (Immunofluorescence, Western blot) and transcript levels (qRT-PCR). RESULTS: Increased GRP78 and decreased VEGF protein levels in sera and placentae of preeclamptic pregnant women and reduced expression of various ER stress markers at both transcript and protein levels was observed in trophoblast cells when they were exposed to recombinant VEGF thereby indicating positive role of VEGF in alleviating ER stress. CONCLUSIONS: Reduced expression of ER stress markers in trophoblast cells against increased VEGF highlighted a new window to explore prospective drugs that can be designed to modulate the activities of various ER stress sensors in order to alleviate ER stress in pregnant women with preeclampsia.

Characteristics of Endophthalmitis after Cataract Surgery in the United States Medicare Population.

PURPOSE: Endophthalmitis is a rare but sight-threatening infection after cataract surgery. Roughly one third of eyes remain blind after treatment. We report United States population-based data on microbiological investigations and treatment patterns plus risk factors for poor outcomes. DESIGN: Retrospective cohort study. PARTICIPANTS: Medicare beneficiaries from 5 states in whom endophthalmitis developed within 6 weeks after cataract surgery in 2003 and 2004. METHODS: We identified endophthalmitis cases occurring after cataract surgery using Medicare billing claims. We contacted treating physicians and requested they complete a questionnaire on clinical and microbiological data and submit relevant medical records. Two independent observers reviewed materials to confirm that cases met a standardized definition. MAIN OUTCOME MEASURES: Positive culture results, vitrectomy status, microbiology spectrum, and final visual acuity. RESULTS: In total, 615 cases met our case definition. Initial visual acuity was counting fingers or worse for 72%. Among 502 cases with known culture results, 291 (58%) had culture positive results. Twelve percent had positive results for streptococci. More than 99% of cases were treated with intravitreal vancomycin. Vitrectomy was performed in 279 cases (45%), including 201 cases with initial acuity better than light perception. Rates of vitrectomy varied across states, with California having the highest rate and Michigan having the lowest (56% and 19% of cases, respectively). Overall, 43% of individuals achieved visual acuity of 20/40 or better. Poor initial acuity (adjusted odds ratio [OR], 1.08; 95% confidence interval [CI], 1.04-1.12 per 0.10 logarithm of the minimum angle of resolution units), older age at diagnosis (OR, 1.22; 95% CI, 1.03-1.45 per 5-year increase), and more virulent organisms were important predictors of poor final visual acuity. Cases with streptococci infection were 10 times more likely to have poor final acuity than coagulase-negative staphylococci cases (adjusted OR, 11.28; 95% CI, 3.63-35.03). Vitrectomy was not predictive of final visual acuity (adjusted OR, 1.26; 95% CI, 0.78-2.04). CONCLUSIONS: Population-based data on the microbiology of acute postoperative endophthalmitis in the United States after cataract surgery are consistent with prior reports. Vitrectomy usage is higher than that recommended from the Endophthalmitis Vitrectomy Study, with no evidence of increased benefit.