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Henig O, Weber G, Hoshen MB, Paul M, German L, Neuberger A, Gluzman I, Berlin A, Shapira C, Balicer RD. Risk factors for and impact of carbapenem-resistant Acinetobacter baumannii colonization and infection: matched case-control study. Eur J Clin Microbiol Infect Dis 2015. [PMID: 26205665 DOI: 10.1007/s10096-015-2452-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The objective of this investigation was to identify risk factors for carbapenem-resistant Acinetobacter baumannii (CRAB) and its association with mortality. A population-based matched case-control study using the computerized database of Clalit Health Services (CHS) in the period between 2007 and 2012 was conducted. Hospitalized patients with CRAB colonization or infection were compared to hospitalized patients without evidence of A. baumannii, matched by age, ward of hospitalization, season, Charlson score, and length of hospitalization. Risk factors for CRAB isolation were searched for using multivariate analysis. Association of CRAB and other risk factors with mortality were assessed in the cohort. A total of 1190 patients with CRAB were matched to 1190 patients without CRAB. Low socioeconomic status was independently associated with CRAB isolation and CRAB bacteremia [odds ratio 2.18, 95% confidence interval (CI) 1.02-5]. Other risk factors were invasive procedures and bacteremia with other pathogens prior to CRAB isolation, and various comorbidities. Among all patients, CRAB isolation was independently associated with increased mortality (hazard ratio 2.33, 95% CI 2.08-2.6). Socioeconomic status is associated with health outcomes. Our population-based study revealed an almost doubled risk for CRAB in patients at lower socioeconomic status and an association with healthcare exposure. CRAB was associated with mortality and might become a risk indicator for complex morbidity and mortality.
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Affiliation(s)
- O Henig
- Infectious Disease Unit, Lady Davis Carmel Medical Center, 7 Michal Street, Haifa, Israel. .,Clalit Research Institute, Chief Physician's Office, Clalit Health Services, Tel Aviv, Israel.
| | - G Weber
- Infectious Disease Unit, Lady Davis Carmel Medical Center, 7 Michal Street, Haifa, Israel.,Technion Faculty of Medicine, Haifa, Israel
| | - M B Hoshen
- Clalit Research Institute, Chief Physician's Office, Clalit Health Services, Tel Aviv, Israel
| | - M Paul
- Division of Infectious Diseases, Rambam Health Care Campus, Haifa, Israel
| | - L German
- Clalit Research Institute, Chief Physician's Office, Clalit Health Services, Tel Aviv, Israel
| | - A Neuberger
- Division of Infectious Diseases, Rambam Health Care Campus, Haifa, Israel.,Technion Faculty of Medicine, Haifa, Israel
| | - I Gluzman
- Clalit Research Institute, Chief Physician's Office, Clalit Health Services, Tel Aviv, Israel
| | - A Berlin
- Clalit Research Institute, Chief Physician's Office, Clalit Health Services, Tel Aviv, Israel
| | - C Shapira
- Technion Faculty of Medicine, Haifa, Israel.,Lady Davis Carmel Medical Center, Haifa, Israel
| | - R D Balicer
- Clalit Research Institute, Chief Physician's Office, Clalit Health Services, Tel Aviv, Israel.,Public Health Department, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
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Abstract
A family of aspartic proteases, the plasmepsins (PMs), plays a key role in the degradation of hemoglobin in the Plasmodium falciparum food vacuole. To study the trafficking of proPM II, we have modified the chromosomal PM II gene in P. falciparum to encode a proPM II-GFP chimera. By taking advantage of green fluorescent protein fluorescence in live parasites, the ultrastructural resolution of immunoelectron microscopy, and inhibitors of trafficking and PM maturation, we have investigated the biosynthetic path leading to mature PM II in the food vacuole. Our data support a model whereby proPM II is transported through the secretory system to cytostomal vacuoles and then is carried along with its substrate hemoglobin to the food vacuole where it is proteolytically processed to mature PM II.
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Affiliation(s)
- Michael Klemba
- Department of Molecular Microbiology, Washington University School of Medicine, 660 S. Euclid Ave., Box 8230, St. Louis, MO 63110, USA
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Klemba M, Gluzman I, Goldberg DE. A Plasmodium falciparum dipeptidyl aminopeptidase I participates in vacuolar hemoglobin degradation. J Biol Chem 2004; 279:43000-7. [PMID: 15304495 DOI: 10.1074/jbc.m408123200] [Citation(s) in RCA: 142] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Intraerythrocytic growth of the human malaria parasite Plasmodium falciparum requires the catabolism of large amounts of host cell hemoglobin. Endoproteolytic digestion of hemoglobin to short oligopeptides occurs in an acidic organelle called the food vacuole. How amino acids are generated from these peptides is not well understood. To gain insight into this process, we have studied a plasmodial ortholog of the lysosomal exopeptidase cathepsin C. The plasmodial enzyme dipeptidyl aminopeptidase 1 (DPAP1) was enriched from parasite extract by two different approaches and was shown to possess hydrolytic activity against fluorogenic dipeptide substrates. To localize DPAP1 we created a transgenic parasite line expressing a chromosomally encoded DPAP1-green fluorescent protein fusion. Green fluorescent protein fluorescence was observed in the food vacuole of live transgenic parasites, and anti-DPAP1 antibody labeled the food vacuole in parasite cryosections. Together these data implicate DPAP1 in the generation of dipeptides from hemoglobin-derived oligopeptides. To assess the significance of DPAP1, we attempted to ablate DPAP1 activity from blood stage parasites by truncating the chromosomal DPAP1-coding sequence. The inability to disrupt the coding sequence indicates that DPAP1 is important for asexual proliferation. The proenzyme form of DPAP1 was found to accumulate in the parasitophorous vacuole of mature parasites. This observation suggests a trafficking route for DPAP1 through the parasitophorous vacuole to the food vacuole.
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Affiliation(s)
- Michael Klemba
- Department of Medicine, Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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Klemba M, Beatty W, Gluzman I, Goldberg DE. Correction: Trafficking of plasmepsin II to the food vacuole of the malaria parasite Plasmodium falciparum. J Biophys Biochem Cytol 2004. [PMCID: PMC2171997 DOI: 10.1083/jcb.2004021616447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Tyas L, Gluzman I, Moon RP, Rupp K, Westling J, Ridley RG, Kay J, Goldberg DE, Berry C. Naturally-occurring and recombinant forms of the aspartic proteinases plasmepsins I and II from the human malaria parasite Plasmodium falciparum. FEBS Lett 1999; 454:210-4. [PMID: 10431809 DOI: 10.1016/s0014-5793(99)00805-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Comparable kinetic parameters were derived for the hydrolysis of peptide substrates and the interaction of synthetic inhibitors with recombinant and naturally-occurring forms of plasmepsin II. In contrast, recombinant plasmepsin I was extended by 12 residues at its N-terminus relative to its naturally-occurring counterpart and a 3-10-fold diminution in the k(cat) values was measured for substrate hydrolysis by the recombinant protein. However, comparable Ki values were derived for the interaction of two distinct inhibitors with both forms of plasmepsin I, thereby validating the use of recombinant material for drug screening. The value of plasmepsin I inhibitors was determined by assessing their selectivity using human aspartic proteinases.
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Affiliation(s)
- L Tyas
- Cardiff School of Biosciences, Cardiff University, UK
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Samoszuk MK, Nguyen V, Gluzman I, Pham JH. Occult deposition of eosinophil peroxidase in a subset of human breast carcinomas. Am J Pathol 1996; 148:701-6. [PMID: 8774125 PMCID: PMC1861714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Degranulation of eosinophils has been observed in a variety of human tumors and in other diseases but has not been previously described in breast cancer. To determine whether eosinophil degranulation also occurs in breast carcinomas, we performed immunohistological studies on cryostat sections obtained from 26 breast cancer biopsies and from 2 benign breast tissues using a monoclonal antibody specific for human eosinophil peroxidase (EPO). For control purposes, the tissues were also immunostained with a mouse IgG1 negative control antibody and with monoclonal mouse anti-human myeloperoxidase. Of the 26 breast cancer specimens, 14 (53%) had extensive, unsuspected deposition of EPO that was located primarily in the connective tissue stroma around and within the tumor. Only 3 of the breast cancer cases had no immunohistochemical evidence of EPO. Thus, 23 of 26 cases of breast cancer (88%) had EPO deposits detectable within or around the tumor. By contrast, none of the benign breast tissues had similar deposits of EPO, and substantial extracellular myeloperoxidase deposition was detectable in only 3 cases of breast cancer. From these studies we conclude that there is eosinophil degranulation and extensive occult deposition of EPO in a major subset of human breast cancers.
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Affiliation(s)
- M K Samoszuk
- Pathology Department, University of California, Irvine, USA
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