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Cappelli A, Damiani C, Capone A, Bozic J, Mensah P, Clementi E, Spaccapelo R, Favia G, Ricci I. Tripartite interactions comprising yeast-endobacteria systems in the gut of vector mosquitoes. Front Microbiol 2023; 14:1157299. [PMID: 37396392 PMCID: PMC10311912 DOI: 10.3389/fmicb.2023.1157299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 05/30/2023] [Indexed: 07/04/2023] Open
Abstract
It is shown that bacteria use yeast as a niche for survival in stressful conditions, therefore yeasts may act as temporary or permanent bacterial reservoirs. Endobacteria colonise the fungal vacuole of various osmotolerant yeasts which survive and multiply in sugar-rich sources such as plant nectars. Nectar-associated yeasts are present even in the digestive system of insects and often establish mutualistic symbioses with both hosts. Research on insect microbial symbioses is increasing but bacterial-fungal interactions are yet unexplored. Here, we have focused on the endobacteria of Wickerhamomyces anomalus (formerly Pichia anomala and Candida pelliculosa), an osmotolerant yeast associated with sugar sources and the insect gut. Symbiotic strains of W. anomalus influence larval development and contribute digestive processes in adults, in addition to exerting wide antimicrobial properties for host defence in diverse insects including mosquitoes. Antiplasmodial effects of W. anomalus have been shown in the gut of the female malaria vector mosquito Anopheles stephensi. This discovery highlights the potential of utilizing yeast as a promising tool for symbiotic control of mosquito-borne diseases. In the present study, we have carried out a large Next Generation Sequencing (NGS) metagenomics analysis including W. anomalus strains associated with vector mosquitoes Anopheles, Aedes and Culex, which has highlighted wide and heterogeneous EB communities in yeast. Furthermore, we have disclosed a Matryoshka-like association in the gut of A stephensi that comprises different EB in the strain of W. anomalus WaF17.12. Our investigations started with the localization of fast-moving bacteria-like bodies within the yeast vacuole of WaF17.12. Additional microscopy analyses have validated the presence of alive intravacuolar bacteria and 16S rDNA libraries from WaF17.12 have identified a few bacterial targets. Some of these EB have been isolated and tested for lytic properties and capability to re-infect the yeast cell. Moreover, a selective competence to enter yeast cell has been shown comparing different bacteria. We suggested possible tripartite interactions among EB, W. anomalus and the host, opening new knowledge on the vector biology.
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Affiliation(s)
- Alessia Cappelli
- School of Biosciences and Veterinary Medicine, University of Camerino, CIRM Italian Malaria Network, Camerino, Italy
| | - Claudia Damiani
- School of Biosciences and Veterinary Medicine, University of Camerino, CIRM Italian Malaria Network, Camerino, Italy
| | - Aida Capone
- School of Biosciences and Veterinary Medicine, University of Camerino, CIRM Italian Malaria Network, Camerino, Italy
| | - Jovana Bozic
- Center for Infectious Disease Dynamics and Huck Institutes of the Life Sciences, Department of Entomology, Penn State University, University Park, PA, United States
| | - Priscilla Mensah
- School of Biosciences and Veterinary Medicine, University of Camerino, CIRM Italian Malaria Network, Camerino, Italy
| | - Emanuela Clementi
- Department of Biology and Biotechnology "L. Spallanzani", University of Pavia, Pavia, Italy
| | - Roberta Spaccapelo
- Department of Medicine and Surgery, University of Perugia, CIRM Italian Malaria Network, Functional Genomic Center (C.U.R.Ge.F), Perugia, Italy
| | - Guido Favia
- School of Biosciences and Veterinary Medicine, University of Camerino, CIRM Italian Malaria Network, Camerino, Italy
| | - Irene Ricci
- School of Biosciences and Veterinary Medicine, University of Camerino, CIRM Italian Malaria Network, Camerino, Italy
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Cappelli A, Valzano M, Cecarini V, Bozic J, Rossi P, Mensah P, Amantini C, Favia G, Ricci I. Killer yeasts exert anti-plasmodial activities against the malaria parasite Plasmodium berghei in the vector mosquito Anopheles stephensi and in mice. Parasit Vectors 2019; 12:329. [PMID: 31266522 PMCID: PMC6604151 DOI: 10.1186/s13071-019-3587-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 06/27/2019] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Wickerhamomyces anomalus is a yeast associated with different insects including mosquitoes, where it is proposed to be involved in symbiotic relationships with hosts. Different symbiotic strains of W. anomalus display a killer phenotype mediated by protein toxins with broad-spectrum antimicrobial activities. In particular, a killer toxin purified from a W. anomalus strain (WaF17.12), previously isolated from the malaria vector mosquito Anopheles stephensi, has shown strong in vitro anti-plasmodial activity against early sporogonic stages of the murine malaria parasite Plasmodium berghei. RESULTS Here, we provide evidence that WaF17.12 cultures, properly stimulated to induce the expression of the killer toxin, can directly affect in vitro P. berghei early sporogonic stages, causing membrane damage and parasite death. Moreover, we demonstrated by in vivo studies that mosquito dietary supplementation with activated WaF17.12 cells interfere with ookinete development in the midgut of An. stephensi. Besides the anti-sporogonic action of WaF17.12, an inhibitory effect of purified WaF17.12-killer toxin was observed on erythrocytic stages of P. berghei, with a consequent reduction of parasitaemia in mice. The preliminary safety tests on murine cell lines showed no side effects. CONCLUSIONS Our findings demonstrate the anti-plasmodial activity of WaF17.12 against different developmental stages of P. berghei. New studies on P. falciparum are needed to evaluate the use of killer yeasts as innovative tools in the symbiotic control of malaria.
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Affiliation(s)
- Alessia Cappelli
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Matteo Valzano
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Valentina Cecarini
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Jovana Bozic
- Florida Medical Entomology Laboratory, University of Florida, Vero Beach, FL, USA
| | - Paolo Rossi
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Priscilla Mensah
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Consuelo Amantini
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Guido Favia
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Irene Ricci
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy.
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Abstract
Purpose
This study aims to investigate the moderating effects of innovation capabilities and social media capabilities on the relationship between brand orientation and brand performance among small- and medium-sized enterprises (SMEs). Drawing on the size differential feature from the organizational ecology theory, the paper further tests variations in these conditions across disaggregated SME levels.
Design/methodology/approach
The empirical part of the study was carried out with a sample of 484 enterprises in an emerging market context via exploratory and confirmatory factor analyses, along with a moderated hierarchical regression.
Findings
Results from the moderated hierarchical regression analysis indicate that although the two capabilities generally offered positive moderating effects across all enterprises, these are conditional and not invariant when disaggregated based on enterprise sizes (small vs medium).
Originality/value
The study suggests the need for enterprise owners/managers to identify optimal combinations of enterprise capabilities, based on their sizes, for which their complementarities with brand orientation efforts are more potent.
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Cappelli A, Capone A, Valzano M, Bozic J, Preziuso S, Mensah P, Varotto Boccazzi I, Rinaldi L, Favia G, Ricci I. Denaturing Gradient Gel Electrophoresis Analysis of Bacteria in Italian Ticks and First Detection of Streptococcus equi in Rhipicephalus bursa from the Lazio Region. Vector Borne Zoonotic Dis 2018; 19:328-332. [PMID: 30418103 DOI: 10.1089/vbz.2018.2364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Tick-borne diseases are an increasing problem for the community. Ticks harbor a complex microbial population acquired while feeding on a variety of animals. Profiling the bacterial population by 16S rDNA amplification and denaturing gradient gel electrophoresis enables detection of the broad spectrum of bacteria that settles in the ticks. This study identified known and unknown tick-infecting bacteria in samples from Italy. Seven adult ticks from different hosts and origins were analyzed: two Rhipicephalus sanguineus ticks from dogs (Lombardia), two Rhipicephalus bursa ticks from bovines (Lazio), and three Ixodes ricinus ticks from humans (Marche). The major result was the first report of the zoonotic agent Streptococcus equi in ticks. S. equi is a species complex of highly contagious pathogens. Subsequent to S. equi detection in a R. bursa tick removed from a bovine of Lazio in 2012, we studied 95 R. bursa samples collected from 3 bovines, 3 ponies, and 1 sheep grazing in the same area in 2012 and from 6 ponies grazing there in 2017. The results of a specific PCR assay indicated a not sporadic occurrence of S. equi in ticks. This finding provides a basis for assessing the potential of ticks to harbor and disperse S. equi.
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Affiliation(s)
- Alessia Cappelli
- 1 School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Aida Capone
- 1 School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Matteo Valzano
- 1 School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Jovana Bozic
- 2 Medical Entomology Lab/IFAS Vero Beach, University of Florida, Vero Beach, Florida.,3 Emerging Pathogens Institute Gainesville, University of Florida, Gainesville, Florida
| | - Silvia Preziuso
- 1 School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Priscilla Mensah
- 1 School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | | | - Laura Rinaldi
- 5 Department of Veterinary Medicine and Animal Production, University of Naples, Naples, Italy
| | - Guido Favia
- 1 School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Irene Ricci
- 1 School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
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Martin E, Varotto Boccazzi I, De Marco L, Bongiorno G, Montagna M, Sacchi L, Mensah P, Ricci I, Gradoni L, Bandi C, Epis S. The mycobiota of the sand fly Phlebotomus perniciosus: Involvement of yeast symbionts in uric acid metabolism. Environ Microbiol 2018; 20:1064-1077. [PMID: 29345102 DOI: 10.1111/1462-2920.14044] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 12/22/2017] [Accepted: 01/08/2018] [Indexed: 01/02/2023]
Abstract
The knowledge of the fungal mycobiota of arthropods, including the vectors of human and animal diseases, is still limited. Here, the mycobiota associated with the sand fly Phlebotomus perniciosus, the main vector of leishmaniasis in the western Mediterranean area, by a culture-dependent approach (microbiological analyses and sequencing of the 26S rRNA gene), internal transcribed spacer (ITS) rRNA amplicon-based next-generation sequencing, fluorescence in situ hybridisation (FISH), and genome sequencing of the dominant yeast species was investigated. The dominant species was Meyerozyma guilliermondii, known for its biotechnological applications. The focus was on this yeast and its prevalence in adults, pupae and larvae of reared sand flies (overall prevalence: 57.5%) and of field-collected individuals (overall prevalence: 9%) was investigated. Using whole-mount FISH and microscopic examination, it was further showed that M. guilliermondii colonizes the midgut of females, males and larvae and the distal part of Malpighian tubules of female sand flies, suggesting a possible role in urate degradation. Finally, the sequencing and analysis of the genome of M. guilliermondii allowed predicting the complete uric acid degradation pathway, suggesting that the yeast could contribute to the removal of the excess of nitrogenous wastes after the blood meal of the insect host.
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Affiliation(s)
- Elena Martin
- Department of Biosciences, University of Milan, Milan, Italy
| | | | - Leone De Marco
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Gioia Bongiorno
- Unit of Vector-Borne Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Matteo Montagna
- Department of Agricultural and Environmental Sciences- Production, Landscape, Agroenergy, University of Milan, Milan, Italy
| | - Luciano Sacchi
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Priscilla Mensah
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Irene Ricci
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino, Italy
| | - Luigi Gradoni
- Unit of Vector-Borne Diseases, Istituto Superiore di Sanità, Rome, Italy
| | - Claudio Bandi
- Department of Biosciences, University of Milan, Milan, Italy.,Pediatric Clinical Research Center Romeo and Enrica Invernizzi, Ospedale 'Luigi Sacco', Milan, Italy
| | - Sara Epis
- Department of Biosciences, University of Milan, Milan, Italy.,Pediatric Clinical Research Center Romeo and Enrica Invernizzi, Ospedale 'Luigi Sacco', Milan, Italy
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Bozic J, Capone A, Pediconi D, Mensah P, Cappelli A, Valzano M, Mancini MV, Scuppa P, Martin E, Epis S, Rossi P, Favia G, Ricci I. Mosquitoes can harbour yeasts of clinical significance and contribute to their environmental dissemination. Environ Microbiol Rep 2017; 9:642-648. [PMID: 28714286 DOI: 10.1111/1758-2229.12569] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 07/07/2017] [Accepted: 07/10/2017] [Indexed: 06/07/2023]
Abstract
There is still a lack of studies on fungal microbiota in mosquitoes, compared with the number available on bacterial microbiota. This study reports the identification of yeasts of clinical significance in laboratory mosquito species: Anopheles gambiae, Anopheles stephensi, Culex quinquefasciatus, Aedes albopictus and Aedes aegypti. Among the yeasts isolated, they focused on the opportunistic pathogen Candida parapsilosis, since there is a need to better understand breakthrough candidaemia with resistance to the usual antifungals, which requires careful consideration in the broad-spectrum therapy, as documented in many clinical reports. C. parapsilosis occurs widely and has been isolated from diverse sources, including insects, which may contribute to its dissemination. In this study, it was isolated from the gut of An. gambiae and its presence in developmental stages and organs of different mosquito species was studied. Our results indicated that there was a stable association between C. parapsilosis and reared mosquitoes during the entire life cycle, and in adult male and female gut and gonads. A wide occurrence of C. parapsilosis was also documented in several populations of wild mosquitoes. Based on these findings, it can be said that mosquitoes might participate in the spreading of this opportunistic pathogen, not only as a carrier.
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Affiliation(s)
- Jovana Bozic
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Gentile da Varano III 62032, Camerino, Italy
| | - Aida Capone
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Gentile da Varano III 62032, Camerino, Italy
| | - Dario Pediconi
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Gentile da Varano III 62032, Camerino, Italy
| | - Priscilla Mensah
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Gentile da Varano III 62032, Camerino, Italy
| | - Alessia Cappelli
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Gentile da Varano III 62032, Camerino, Italy
| | - Matteo Valzano
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Gentile da Varano III 62032, Camerino, Italy
| | - Maria Vittoria Mancini
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Gentile da Varano III 62032, Camerino, Italy
| | - Patrizia Scuppa
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Gentile da Varano III 62032, Camerino, Italy
| | - Elena Martin
- Department of Veterinary Sciences and Public Health, University of Milan, Milan, 20133, Italy
| | - Sara Epis
- Department of Veterinary Sciences and Public Health, University of Milan, Milan, 20133, Italy
| | - Paolo Rossi
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Gentile da Varano III 62032, Camerino, Italy
| | - Guido Favia
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Gentile da Varano III 62032, Camerino, Italy
| | - Irene Ricci
- School of Biosciences and Veterinary Medicine, University of Camerino, Via Gentile da Varano III 62032, Camerino, Italy
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Canedo-Arguelles M, Hawkins CP, Kefford BJ, Schafer RB, Dyack BJ, Brucet S, Buchwalter D, Dunlop J, Fror O, Lazorchak J, Coring E, Fernandez HR, Goodfellow W, Achem ALG, Hatfield-Dodds S, Karimov BK, Mensah P, Olson JR, Piscart C, Prat N, Ponsa S, Schulz CJ, Timpano AJ. Saving freshwater from salts. Science 2016; 351:914-6. [DOI: 10.1126/science.aad3488] [Citation(s) in RCA: 183] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Ghazavi M, Bamford MW, Mensah P, Harman KE. Antiphospholipid syndrome masquerading as necrotising fasciitis. J Plast Reconstr Aesthet Surg 2012; 65:e322-3. [PMID: 22633390 DOI: 10.1016/j.bjps.2012.05.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 05/02/2012] [Accepted: 05/06/2012] [Indexed: 10/28/2022]
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Adu-Sarkodie Y, Mensah P, Opoku BK, Mayaud P, Peeling R. P1-S1.48 Prevalence of syphilis in antenatal clinic attenders and associated risk factors. Br J Vener Dis 2011. [DOI: 10.1136/sextrans-2011-050108.48] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Shah A, Ahmed S, Karlapudi K, Sherman J, Mensah P. P277 The use of an indwelling urinary catheter prior to caesarean delivery. Audit at a District General Hospital in the UK. Int J Gynaecol Obstet 2009. [DOI: 10.1016/s0020-7292(09)61767-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Czyz J, Dziadziuszko R, Knopinska-Postuszuy W, Hellmann A, Kachel L, Holowiecki J, Gozdzik J, Hansz J, Avigdor A, Nagler A, Osowiecki M, Walewski J, Mensah P, Jurczak W, Skotnicki A, Sedzimirska M, Lange A, Sawicki W, Sulek K, Wach M, Dmoszynska A, Kus A, Robak T, Warzocha K. Outcome and prognostic factors in advanced Hodgkin's disease treated with high-dose chemotherapy and autologous stem cell transplantation: a study of 341 patients. Ann Oncol 2004; 15:1222-30. [PMID: 15277262 DOI: 10.1093/annonc/mdh304] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The reported probability of survival of patients with Hodgkin's disease (HD) following high-dose chemotherapy with autologous stem cell transplantation (HDC/ASCT) is 35-65% at 5 years. The Polish Lymphoma Research Group investigated retrospectively prognostic factors for overall survival (OS) and event-free survival (EFS), and the risk of secondary malignancies in a large series of patients who underwent HDC/ASCT. PATIENTS AND METHODS The data of 341 consecutive patients treated in 10 centers from 1990 to 2002 were collected and analyzed. RESULTS The actuarial 5-year OS and EFS were 64% [95% confidence interval (CI) 57% to 71%] and 45% (95% CI 39% to 51%), respectively. In the multivariate model, unfavorable prognostic factors for EFS were less than partial response at the time of ASCT [relative risk (RR), 2.92 (95% CI 1.68-5.08); P<0.001] and three or more previous chemotherapy lines (RR, 2.16; 95% CI 1.42-3.30; P<0.001). These two factors were also associated with unfavorable OS (RR, 3.32; 95% CI 1.90-5.79; P<0.001 and RR, 2.34, 95% CI 1.51-3.64; P<0.001). Five-year cumulative risk of secondary malignancy was 8.4% (95% CI 2% to 13%) and the only identified risk factor was splenectomy (P=0.02). CONCLUSIONS HDC/ASCT should be considered early in the course of disease for patients with a response after standard therapy.
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Affiliation(s)
- J Czyz
- Medical University of Gdansk, Gdansk, Poland.
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Mensah P, Jurczak W, Piatkowska - Jakubas B, Walter Z, Hawrylecka D, Skotnicki AB. Prolonged hematopoietic reconstitution in patients failing previous peripheral blood stem cell collection, transplanted with adequate number of the CD34 cells obtained during bone marrow harvest. J Clin Oncol 2004. [DOI: 10.1200/jco.2004.22.90140.6641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- P. Mensah
- Collegium Medicum UJ, Kraków, Poland
| | | | | | - Z. Walter
- Collegium Medicum UJ, Kraków, Poland
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Abstract
AIMS The purpose of this study was to investigate the antibiotic resistance and clonal lineage of serogroup B Salmonella isolated from patients suspected of suffering from enteric fever in Accra, Ghana. METHODS AND RESULTS Serogroup B Salmonella were isolated from blood (n=28), cerebral spinal fluid (CSF) (n=1), or urine (n=2), and identified based on standard biochemical testing and agglutinating antisera. Isolates were examined for their susceptibility to ampicillin, chloramphenicol, tetracycline and trimethoprim-sulfamethoxazole. Most of the isolates could be classified as multiple-drug resistant. Furthermore, the genetic location of resistance genes was shown to be on conjugative plasmids. Genetic fingerprinting by plasmid profiling, enterobacterial repetitive intergenic consensus (ERIC)-PCR, and repetitive element (REP)-PCR were performed to determine the diversity among the isolates. Plasmid profiling discriminated five unique groupings, while ERIC-PCR and REP-PCR resulted in two and three groupings, respectively. CONCLUSIONS A high rate of antibiotic resistance was associated with the Salmonella isolates and the genes responsible for the resistance are located on conjugative plasmids. Also, there appears to be minimal diversity associated with the isolates. SIGNIFICANCE AND IMPACT OF THE STUDY As a result of the increasing antibiotic resistance among bacteria of all genera, surveys to monitor microbial populations are critical to determine the extent of the problem. The inability to treat many infectious diseases with current antibiotic regimens should prompt the medical community to be more prudent with its antibiotic use.
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Affiliation(s)
- F Mills-Robertson
- Centre for Scientific Research Into Plant Medicine, WHO Collaborating Centre for Traditional Medicine, PO Box 73, Mampong-Akwapim, Ghana
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Czyz J, Hellmann A, Dziadziuszko R, Hansz J, Goździk J, Hołowiecki J, Stella-Hołowiecka B, Kachel Ł, Knopińska-Posłuszny W, Nagler A, Meder J, Walewski J, Lampka E, Sułek K, Sawicki W, Lange A, Forgacz K, Suchnicki K, Pacuszko T, Skotnicki A, Mensah P, Jurczak W, Kuliczkowski K, Wróbel T, Mazur G, Dmoszyńska A, Wach M, Robak T, Warzocha K. High-dose chemotherapy with autologous stem cell transplantation is an effective treatment of primary refractory Hodgkin's disease. Retrospective study of the Polish Lymphoma Research Group. Bone Marrow Transplant 2002; 30:29-34. [PMID: 12105774 DOI: 10.1038/sj.bmt.1703590] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2001] [Accepted: 03/21/2002] [Indexed: 11/08/2022]
Abstract
We analysed the treatment outcome of primary refractory HD patients managed with high-dose chemotherapy and haematopoietic cell transplantation. Data of 65 adult patients who underwent HDC/ASCT in nine Polish centres for primary resistant Hodgkin's disease between June 1991 and July 2000 were collected retrospectively. Response rate to HDC/ASC: CR, 54%; PR, 20%; less than PR, 15%; early deaths, 11%. Actuarial 3-year OS and PFS were 55% and 36%, respectively. In multivariate analysis, lack of bulky lymph nodes and use of immunotherapy were favourable factors for both OS and PFS. IPF <3 at the time of transplantation was predictive for PFS. However, the prognostic impact of immunotherapy should be interpreted with caution since this group included more patients who achieved CR after HDC/ASCT. The results of HDC/ASCT are encouraging and confirm earlier findings. The role of immunotherapy should be further investigated in prospective trials.
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Affiliation(s)
- J Czyz
- Department of Haematology, Medical University, Gdańsk, ul. Debinki, Poland
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Sackey BA, Mensah P, Collison E, Sakyi-Dawson E. Campylobacter, Salmonella, Shigella and Escherichia coli in live and dressed poultry from metropolitan accra. Int J Food Microbiol 2001; 71:21-8. [PMID: 11764888 DOI: 10.1016/s0168-1605(01)00595-5] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This study on the microbiology of chicken assessed a total of 97 live birds from three selected farms and 87 carcasses/chicken parts from two supermarkets, two open markets and one wholesale outlet (cold store) in the Accra metropolis. Campylobacter spp. were isolated from 14 (14.4%) gut contents of live birds from three farms. None of the frozen birds were positive for Campylobacter spp. These isolates were sensitive to most common antibiotics but not to ampicillin and tetracyclines. Salmonella spp. were isolated from 7 (7.2%) gut contents and 13 (6.8%) carcasses and were resistant to erythromycin. cefotiam, penicillin, ampicillin and cefadroxil. Samonella spp. had varied susceptibilities to nalidixic acid, chloramphenicol and minocyclin. No Shigella spp. was isolated from any of the live birds but 6 (6.9%) of imported chicken samples from the cold store and two markets were positive. Fosfomycin and chloramphenicol were the only antibiotics effective against these isolates. Twelve different Escherichia coli serovars were identified from the total of 21 positive samples. These, in order of magnitude isolated, are E. coli 0158 (14.3%), 0125 (14.3%), 025 (9.5%), 028ac (9.5%), 0159 (9.5%). 015 (9.5%), 0126 (9.5%), 063 (4.8%), 0143 (4.8%), 026 (4.8%), 078 (4.8%), 0164 (4.8%). Cefadroxil, ampicillin, penicillin, cefotiam, tetracycline and erythromycin were ineffective against all strains of E. coli isolated. Minocyclin was effective against all strains with the exception of E. coli 0159, 025, 0164 and 063, which were moderately susceptible. All strains with exception of E. coli 0164 were susceptible to fosfomycin. Nalidixic acid, chloramphenicol, kanamaycin, ceftrioxone and amoxycillin all showed varied effectiveness against the strains isolated. It is concluded that imported and locally produced chicken is a potential source of multiple-antibiotic-resistant enteropathogenic bacteria. Measures to improve the microbial quality of chicken are discussed.
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Affiliation(s)
- B A Sackey
- Department of Food Science and Nutrition, University of Ghana, Legon
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Salamanchuk Z, Jakóbczyk M, Mensah P, Skotnicki AB. Novel translocation (5;18)(q31;q23) in biphenotypic acute leukemia. Cancer Genet Cytogenet 2001; 131:92-3. [PMID: 11734328 DOI: 10.1016/s0165-4608(01)00490-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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18
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Mensah P, Carta G. Adsorptive control of water in esterification with immobilized enzymes. Continuous operation in a periodic counter-current reactor. Biotechnol Bioeng 1999; 66:137-46. [PMID: 10577467] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
A periodic counter-current adsorptive-reactor system is developed to carry out continuous esterifications in organic solvents with immobilized enzymes. The system comprises a number of fixed-beds distributed between a reaction-adsorption zone and a regeneration zone and operated in a "merry-go-round" sequence. Water formed in the reaction is adsorbed preventing the formation of a free-water phase and deactivation of the biocatalyst. The adsorbed water is, in turn, recovered by desorption in the regeneration zone. The concept is tested experimentally on a laboratory-scale using, as a model, the esterification of isoamyl alcohol and propionic acid in hexane catalyzed by an immobilized lipase. Pure isoamyl alcohol is used as a regenerant to remove excess water from the biocatalyst. In the periodic steady-state, improvements in ester productivity greater than 50% over that achievable with a conventional fixed-bed reactor are demonstrated experimentally with just two beds in a series arrangement. Use of a water-selective adsorbent in conjunction with the biocatalyst provides further improvements by reducing accumulation of water on the enzyme. A mathematical model is also developed to predict the thermodynamic activity of water along the reactor and describe the dynamic behavior of the system. The model, based on independently developed rate and equilibrium parameters, successfully predicts the experimental behavior and provides an effective tool for scale-up and optimization.
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Affiliation(s)
- P Mensah
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22903-2442, USA
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Walter Z, Szostek M, Mensah P, Lorenz F, Weglarska D, Skotnicki AB. [Methods of mobilizing hematopoietic cells, their collection using cell separation, purging--processing of pathologic cells and enrichment with CD 34+ cells--negative and positive selection]. Przegl Lek 1999; 56 Suppl 1:22-7. [PMID: 10494178] [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: 02/14/2023]
Abstract
Autological transplantation of bone marrow as well as hematopoietic and precursor cells obtained from peripheral blood with the use of cell apheresis is a therapy applied in the treatment of hematological diseases and solid tumours. The mobilization of hematopoietic cells is performed by applying cytostatic drugs and/or recombinant growth factors (G-CSF, GM-CSF). The collection of CD 34+ cells is performed by using cell separators. An important role in the transplantation procedure is played by purging techniques of transplantation material from residual neoplastic cells (negative selection) or isolation of hematopoietic cells (positive selection). The considerable progress in this field is connected with the implementation of Immunoadsorbtive or magnetic methods as well as those of molecular biology. The improvement of the procedure of hematopoietic cells transplantation and its efficacy is caused by the stimulation of the hematopoiesis by using the combination of cytokines (G-CSF, GM-CSF, IL-3, SCF) and purging of the hematopoietic cells obtained from the cellular apheresis.
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Affiliation(s)
- Z Walter
- Kliniki Hematologii Collegium Medicum, Uniwersytetu Jagielońskiego w Krakowie.
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Jurczak W, Nowak WS, Mensah P, Skotnicki AB. [Hodgkin's disease--diagnostic basis and therapy in light of randomized clinical trials]. Przegl Lek 1999; 56 Suppl 1:90-100. [PMID: 10494189] [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: 02/14/2023]
Abstract
Hodgkin Disease has a relatively good prognosis and high curability due to the effectiveness of risk adapted treatment. Protocol currently used at the Department of Haematology in Cracow is based on randomised multicentre clinical trials, summarised in this paper. Proper choice of the first line treatment is most important for overall survival--no salvage therapy for resistant or recurrent disease is equally effective. High dose chemotherapy with autologous stem cell support should be considered in certain clinical situations, as partial response or relapse after conventional treatment.
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Affiliation(s)
- W Jurczak
- Kliniki Hematologii Collegium Medicum, Uniwersytetu Jagiellońksiego w Krakowie
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Abstract
Experimental and theoretical studies are conducted to understand the dynamic behavior of a continuous-flow fixed-bed reactor in which an esterification is catalyzed by an immobilized enzyme in an organic solvent medium. The experimental system consists of a commercial immobilized lipase preparation known as Lipozyme as the biocatalyst, with propionic acid and isoamyl alcohol (dissolved in hexane) as the reaction substrates. A complex dynamic behavior is observed experimentally as a result of the simultaneous occurrence of reaction and adsorption phenomena. Both propionic acid and water are adsorbed by the biocatalyst resulting in lower reaction rates. In addition, an excessive accumulation of water in the reactor leads to a rapid irreversible inactivation of the enzyme. A model based on previously-obtained adsorption isotherms and kinetic expressions, as well as on adsorption rate measurements obtained in this work, is used to predict the concentration and thermodynamic activity of water along the reactor length. The model successfully predicts the dynamic behavior of the reactor and shows that a maximum thermodynamic activity of water occurs at a point at some distance from the reactor entrance. A cation exchange resin in sodium form, packed in the reactor as a selective water adsorbent together with the catalyst particles, is shown to be an effective means for preventing an excessive accumulation of water formed in the reaction. Its use results in longer cycle times and greater productivity. As predicted by the model, the experimental results show that the water adsorbed on the catalyst and on the ion exchange resin can be removed with isoamyl alcohol with no apparent loss in enzyme activity.
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Affiliation(s)
- P Mensah
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22903-2442, USA
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Abstract
Reducing the influence of an undesired product in an enzymatic reaction could have a significant impact on the productivity of such systems. Here, we focus on the removal of water formed during an enzymatic esterification in a batch reactor. A commercial immobilized lipase preparation, known as Lipozyme, is used as the biocatalyst and propionic acid and isoamyl alcohol dissolved in hexane are the substrates. In this system, the water formed will partition between the catalyst and the medium. As the more polar reactants are converted into the less polar ester product, the water is partitioned more towards the biocatalyst and the accumulation of water eventually causes lower reaction rates. Addition of a strong-acid cation exchange resin in sodium form is found to control the water accumulation on the biocatalyst without stripping the essential water needed for the enzyme to function and substantial improvements in conversion are achieved. A mathematical model is developed to describe the batch reaction behavior with and without added absorbent, which successfully predicts the behavior of water and its effects.
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Affiliation(s)
- P Mensah
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22903-2442, USA
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Mensah P, Ndiokwelu CI, Uwaegbute A, Ablordey A, van Boxtel AM, Brinkman C, Nout MJ, Ngoddy PO. Feeding of lactic acid-fermented high nutrient density weaning formula in paediatric settings in Ghana and Nigeria: acceptance by mother and infant and performance during recovery from acute diarrhoea. Int J Food Sci Nutr 1995; 46:353-62. [PMID: 8574862 DOI: 10.3109/09637489509012567] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A period of acute diarrhoea in infants is often associated with anorexia and weight loss. Catch-up growth is, therefore, necessary and this depends very much on the type of food, in terms of nutrient density, protein quality and digestibility, given to the child. Fermented (F) and non-fermented (NF) maize-soybean porridges of increased nutrient density were formulated and compared with traditionally fermented maize-only porridge (P) for acceptability using mothers in peri-urban Ghana as well as urban Nigeria as subjects. Subsequently, infants hospitalised in paediatric wards for acute diarrhoea, from the same communities in both countries, were assigned randomly to one or other of the three porridges. Infant subjects in all cases fell within the ages of 6-15 months. Complementary to regular breast-feeding, infants could consume as much porridge as they wanted and their total daily consumption was interpreted as an indication of acceptance. Although mothers in both the environments of Ghana and Nigeria rated P as more acceptable than F and NF, no significant difference was recorded in the quantitative intake by infants of the three formula groups. By adding enzyme-rich cereal malt flour (at the 1-5% level by weight) as a viscosity-thinning agent to F and NF porridges, it was possible to feed these porridges to infants at total solids concentration levels of 20-25% (wet basis) which is approximately double the solid matter content of the P porridge. Consequently, the daily nutrient intake by infants consuming F and NF porridges was considerably higher compared to the P porridge group. It is concluded that the concept of high nutrient density weaning foods is a feasible vehicle for an improvement of nutrient supply to infants.
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Affiliation(s)
- P Mensah
- Noguchi Memorial Institute for Medical Research, Legon, Ghana
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Abstract
Unhygienic conditions of a typical rural community in a developing country were simulated in the laboratory by inoculating fermented maize dough porridge with Shigella flexneri and enterotoxigenic Escherichia coli (ETEC). The antimicrobial effects of the different processes involved in the preparation of fermented maize dough porridge were assessed. The soaking process reduced the pH but no antimicrobial effect against shigella and ETEC was noted. Unfermented maize dough did not inhibit any of the test strains. When the fermentation process had become established, half of the strains tested were inhibited by the fermented maize dough when examined 8 h after inoculation. Cooking the fermented maize dough into porridge reduced the antimicrobial effect but there was still significant inhibition of pathogens. This suggests that the antimicrobial effect of fermented maize dough is not due to pH per se. Fermentation of maize dough appears to be a useful strategy for reducing contamination of weaning foods by Sh. flexneri and ETEC. The possible nature of the antimicrobial agent(s) produced during the fermentation of maize dough is discussed.
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Affiliation(s)
- P Mensah
- Noguchi Memorial Institute for Medical Research, University of Ghana, Legon
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Mensah P, Deadwyler S. The caudate nucleus of the rat: cell types and the demonstration of a commissural system. J Anat 1974; 117:281-93. [PMID: 4142635 PMCID: PMC1231402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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Lynch G, Gall C, Mensah P, Cotman CW. Horseradish peroxidase histochemistry: a new method for tracing efferent projections in the central nervous system. Brain Res 1974; 65:373-80. [PMID: 4137706 DOI: 10.1016/0006-8993(74)90229-7] [Citation(s) in RCA: 95] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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