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Klempt M, Franz CMAP, Hammer P. Characterization of coagulase-negative staphylococci and macrococci isolated from cheese in Germany. J Dairy Sci 2022; 105:7951-7958. [PMID: 35965117 DOI: 10.3168/jds.2022-21941] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 05/23/2022] [Indexed: 11/19/2022]
Abstract
Cheese, especially ripened varieties, harbor a very complex and heterogeneous microbiota. In addition to the desired microorganisms (starter cultures) added during cheese production, potentially harmful bacteria may also enter the production chain. Regarding the latter, the focus of this study was on coagulase-negative staphylococci (CNS) and Macrococcus caseolyticus. Both are known to harbor a variety of genes coding for antibiotic resistance, including mecA, mecB, mecC, and mecD. Coagulase-negative staphylococci or macrococci carrying such genes or other virulence factors should not be present in cheese. Cheese samples (101 in total) were collected from retail sources. Coagulase-negative staphylococci and M. caseolyticus were isolated utilizing selective agars, and species were identified by phenotypical tests and partial sequencing of the sodA gene. The results allowed identification of 53 CNS strains and 19 M. caseolyticus strains. Among the CNS, 11 isolates of Staphylococcus saprophyticus and one Staphylococcus epidermidis isolate were obtained. Both species are potential human pathogens and may thus adversely affect the safety of these food products. Screening for antimicrobial resistance was performed by application of disc diffusion tests, a gradient strip-test, and 14 different PCR tests. Evidence for methicillin resistance (by either positive disc diffusion assay for cefoxitin or by mec PCR) was found in CNS isolates and M. caseolyticus (9 isolates each). Regarding other virulence factors, no genetic determinants for coagulase or the most common staphylococcal enterotoxins sea, seb, sec, sed, and see were detected in any of the CNS or M. caseolyticus isolates by PCR testing. In conclusion, the presence of facultatively pathogenic CNS and carriers of genes for antibiotic resistance in both groups of microorganisms, especially mec genes, and the respective food safety issues need further evaluation and surveillance.
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Affiliation(s)
- M Klempt
- Department of Microbiology and Biotechnology, Max Rubner-Institute, Federal Research Institute of Nutrition and Food, 24103 Kiel, Germany
| | - C M A P Franz
- Department of Microbiology and Biotechnology, Max Rubner-Institute, Federal Research Institute of Nutrition and Food, 24103 Kiel, Germany
| | - P Hammer
- Department of Microbiology and Biotechnology, Max Rubner-Institute, Federal Research Institute of Nutrition and Food, 24103 Kiel, Germany.
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Hammer P, Ireland K, Houghton DC, Jaggers A, Coleman A, Snir OL, Troxell ML, Andeen NK. One Hundred Years of the Pathology Medical Student Fellowship. Arch Pathol Lab Med 2021; 146:1037-1042. [PMID: 34784414 DOI: 10.5858/arpa.2021-0220-oa] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/23/2021] [Indexed: 11/06/2022]
Abstract
CONTEXT.— The Pathology Medical Student Fellowship (PSF) is a unique, year-long immersive educational experience. Review of institutional archives describes a medical student "Fellowship in Pathology" founded in 1919. OBJECTIVE.— To characterize the impacts of this 100-year-old program. DESIGN.— We determined subsequent medical specialty of each PSF graduate in our department and surveyed those with available contact information. RESULTS.— Of 145 pathology student fellows graduating between 1924 and 2020, a total of 50 (34.4%) matched into pathology; medical, surgical, and radiology subspecialties were also well-represented career choices. Between 2001 and 2020, of 36 students who matched into pathology from our institution, 19 (52.8%) had completed the fellowship. Survey respondents (n = 42) indicated that before the PSF, 11 of 42 students (26.2 %) were undecided in specialty, with only 6 (14.3%) identifying pathology as their primary field of interest. Of survey respondents who had completed training, 26 (61.9%) practice in academic settings. Nonpathology physicians reported frequent utilization of skills gained during the PSF year, with 5 of 23 (21.7%) responding "daily," and 9 (39.1%) responding "weekly." The most useful skills included knowledge of pathophysiology of disease and anatomy, improved communication with multidisciplinary teams, and/or interpretation of pathology results (each selected by 17 to 20 students, 73.9%-87.0%). Free-text responses on impacts of the PSF described enhanced knowledge of disease pathobiology and diagnostic complexity and increased confidence and autonomy. CONCLUSIONS.— We describe the program structure, educational benefits, graduate specialty choices, and career impacts of 100 years of the PSF at our institution. Although undecided before pathology exposure, many PSF graduates subsequently enter pathology careers. Regardless of specialty choice, PSF graduates have a high rate of subsequently pursuing academic medical careers.
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Affiliation(s)
- Phoebe Hammer
- From the Department of Pathology, Oregon Health & Science University, Portland (Hammer, Ireland, Houghton, Jaggers, Coleman, Snir, Andeen).,the Department of Pathology, Stanford University, Stanford, California (Hammer, Troxell)
| | - Karen Ireland
- From the Department of Pathology, Oregon Health & Science University, Portland (Hammer, Ireland, Houghton, Jaggers, Coleman, Snir, Andeen)
| | - Donald C Houghton
- From the Department of Pathology, Oregon Health & Science University, Portland (Hammer, Ireland, Houghton, Jaggers, Coleman, Snir, Andeen)
| | - Alexis Jaggers
- From the Department of Pathology, Oregon Health & Science University, Portland (Hammer, Ireland, Houghton, Jaggers, Coleman, Snir, Andeen)
| | - Anya Coleman
- From the Department of Pathology, Oregon Health & Science University, Portland (Hammer, Ireland, Houghton, Jaggers, Coleman, Snir, Andeen)
| | - Olivia L Snir
- From the Department of Pathology, Oregon Health & Science University, Portland (Hammer, Ireland, Houghton, Jaggers, Coleman, Snir, Andeen)
| | - Megan L Troxell
- the Department of Pathology, Stanford University, Stanford, California (Hammer, Troxell)
| | - Nicole K Andeen
- From the Department of Pathology, Oregon Health & Science University, Portland (Hammer, Ireland, Houghton, Jaggers, Coleman, Snir, Andeen)
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3
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Hammer P, Latour E, Bohnett MC, McKenzie F, Korcheva VB, Mengden S, White KP, Ortega-Loayza AG. The utility and challenges of histopathologic evaluation in the diagnosis of nonmalignant skin ulcers. Wound Repair Regen 2019; 28:219-223. [PMID: 31705777 DOI: 10.1111/wrr.12780] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 10/17/2019] [Accepted: 11/06/2019] [Indexed: 12/12/2022]
Abstract
Histopathologic evaluation of cutaneous ulcers is indicated when the clinical diagnosis is unclear or when ulcers have not responded to standard of care. Many nonmalignant skin ulcers lack specific histologic findings on biopsy and pose a diagnostic challenge. While the usefulness of skin biopsies to diagnose underlying malignancy in ulcerated lesions has been demonstrated in previous studies, their utility in the diagnosis of ulcers of other etiologies has not been reported. We conducted a retrospective study of 45 nonmalignant ulcer biopsies in a 3-year period to compare the histologic diagnosis with the final diagnosis. Additionally, we assessed the diagnostic concordance among three blinded dermatopathologists when reviewing these cases. The leading histologic diagnosis from each of the three observers agreed with the final clinical diagnosis, on average, for 29.6% of the cases (average pairwise kappa = 0.15). Inflammatory ulcers had the lowest concordance between the observers and final diagnosis with an average of 26.0% of cases (average pairwise kappa = 0.06). The observers agreed with each other for 35.6% of the cases (Fleiss' kappa = 0.32). The highest agreement among observers was in the vascular/vasculopathic category (50%, Fleiss' kappa = 0.44). Our results indicate that skin biopsies alone are useful in the evaluation of nonmalignant ulcers to rule out other conditions (e.g. neoplasm) but frequently not sufficient to establish a definitive diagnosis. Additional clinicopathologic correlation is necessary in the final assessment of nonmalignant ulcers to determine the diagnosis. Future research endeavors should explore alternative approaches to more efficiently diagnose nonmalignant skin ulcers.
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Affiliation(s)
- Phoebe Hammer
- Oregon Health & Science University, Department of Dermatology, Portland, Oregon, USA
| | - Emile Latour
- Biostatistics Shared Resource, Knight Cancer Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - Mary C Bohnett
- Oregon Health & Science University, Department of Dermatology, Portland, Oregon, USA
| | - Fatima McKenzie
- Oregon Health & Science University, Department of Dermatology, Portland, Oregon, USA
| | - Veselina B Korcheva
- Oregon Health & Science University, Department of Dermatology, Portland, Oregon, USA
| | - Stephanie Mengden
- Oregon Health & Science University, Department of Dermatology, Portland, Oregon, USA
| | - Kevin P White
- Oregon Health & Science University, Department of Dermatology, Portland, Oregon, USA
| | - Alex G Ortega-Loayza
- Oregon Health & Science University, Department of Dermatology, Portland, Oregon, USA
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Haynes D, Hammer P, Malachowski SJ, Kaffenberger B, Yi JS, Vera N, Calhoun C, Shinohara MM, Seminario-Vidal L, Trinidad JC, Keller JJ, Ortega-Loayza AG. Characterisation and diagnosis of ulcers in inpatient dermatology consultation services: A multi-centre study. Int Wound J 2019; 16:1440-1444. [PMID: 31475449 DOI: 10.1111/iwj.13211] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 08/18/2019] [Indexed: 12/20/2022] Open
Abstract
Accurate and prompt diagnosis of skin ulcers is critical to optimise management; however, studies in hospitalised patients are limited. This retrospective review of dermatologic consultations included 272 inpatients with skin ulcers between July 2015 and July 2018 in four U.S. academic hospitals. The median age was 54 years and 45% were male. In 49.3% of the patients, skin ulcers were considered the primary reason for admission. Ulcers of 62% were chronic and 49.6% were located on the lower extremities. Pyoderma gangrenosum (17.3%), infection (12.5%), and exogenous causes (11.8%) were the leading aetiologies; 12% remained diagnostically inconclusive after consultation. Diagnostic agreements pre-dermatology and post-dermatology consult ranged from 0.104 (n = 77, 95% CI 0.051-0.194) to 0.553 (n = 76, 95% CI 0.440-0.659), indicating poor-modest agreement. This study highlights the diagnostic complexity and relative incidences of skin ulcers in the inpatient setting.
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Affiliation(s)
- Dylan Haynes
- Oregon Health & Science University, Department of Dermatology, Portland, Oregon
| | - Phoebe Hammer
- Oregon Health & Science University, School of Medicine, Portland, Oregon
| | | | | | - Jonathan S Yi
- University of Washington, Division of Dermatology, Seattle, Washington
| | - Nora Vera
- University of South Florida, Department of Dermatology, Tampa, Florida
| | - Cody Calhoun
- Ohio State University, Department of Dermatology, Columbus, Ohio
| | - Michi M Shinohara
- University of Washington, Division of Dermatology, Seattle, Washington
| | | | - John C Trinidad
- Ohio State University, Department of Dermatology, Columbus, Ohio
| | - Jesse J Keller
- Oregon Health & Science University, Department of Dermatology, Portland, Oregon
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Hammer P, Jordan J, Jacobs C, Klempt M. Characterization of coagulase-negative staphylococci from brining baths in Germany. J Dairy Sci 2019; 102:8734-8744. [PMID: 31421877 DOI: 10.3168/jds.2018-15610] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 06/19/2019] [Indexed: 12/17/2022]
Abstract
Brining is an important step in cheese making, and using brine baths for this purpose is common practice in German dairies. Time of brining, brine concentration, and composition of the complex and heterogeneous microbiota, including coagulase-negative staphylococci (CNS), contribute to the ripening and taste of cheese. As well as producing staphylococcal enterotoxins, some CNS show antibiotic resistance; therefore, we isolated 52 strains of presumptive CNS from cheese brines from 13 factories in Germany. Species identification by sodA gene sequencing revealed that 50 isolates were CNS: 31 Staphylococcus saprophyticus, 4 Staphylococcus carnosus, 4 Staphylococcus equorum, 3 Staphylococcus sciuri, 2 Staphylococcus hominis, and 2 Staphylococcus warneri. One isolate each was identified as Staphylococcus epidermidis, Staphylococcus pasteurii, Staphylococcus succinus, and Staphylococcus xylosus. Further subtyping of the Staph. saprophyticus isolates to the subspecies level revealed the presence of 6 Staph. saprophyticus ssp. saprophyticus. Using pulsed-field gel electrophoresis with the identified Staph. saprophyticus strains, 12 independent clones were identified, resulting in the exclusion of 18 strains from further testing. In 19 of the remaining 32 CNS isolates, resistance to antibiotics was observed. Resistance was found against oxacillin (17), penicillin (5), and cefoxitin (1). Four isolates expressed resistance to both oxacillin and penicillin. No resistance was found to enrofloxacin, tetracycline, gentamicin, or erythromycin. Then, PCR analysis for antibiotic resistance genes was performed for 22 different genes. Only genes blaZ and blaTEM were found in 7 isolates. These isolates were selected for challenge tests with different concentrations of lactic acid and NaCl to examine whether expression of antibiotic resistance was influenced by these stressors. An increase in the minimal inhibitory concentration from 0 to 2.0 µg/mL was seen for trimethoprim/sulfamethoxazole only in one isolate of Staph. saprophyticus at an increased lactic acid concentration. Finally, all isolates were tested for genetic determinants (entA, entB, entC, entD, and entE) of the most common staphylococcal enterotoxins; none of these genes were detected. We found no indication for unacceptable risks originating from the isolated CNS.
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Affiliation(s)
- P Hammer
- Department of Safety and Quality of Milk and Fish Products, Max Rubner-Institut, Federal Research Institute of Nutrition and Food, 24103 Kiel, Germany.
| | - J Jordan
- Department of Safety and Quality of Milk and Fish Products, Max Rubner-Institut, Federal Research Institute of Nutrition and Food, 24103 Kiel, Germany
| | - C Jacobs
- Department of Safety and Quality of Milk and Fish Products, Max Rubner-Institut, Federal Research Institute of Nutrition and Food, 24103 Kiel, Germany
| | - M Klempt
- Department of Safety and Quality of Milk and Fish Products, Max Rubner-Institut, Federal Research Institute of Nutrition and Food, 24103 Kiel, Germany
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6
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Hammer P, White K, Mengden S, Korcheva V, Raess PW. Nipple leiomyoma: A rare neoplasm with a broad spectrum of histologic appearances. J Cutan Pathol 2019; 46:343-346. [PMID: 30663114 DOI: 10.1111/cup.13423] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Revised: 01/07/2019] [Accepted: 01/14/2019] [Indexed: 11/29/2022]
Abstract
Cutaneous leiomyomas are rare benign smooth-muscle tumors. These lesions are distinguished based on their cell of origin and are subclassified as pilar leiomyoma, angioleiomyoma, and genital-type leiomyoma. Nipple leiomyoma is the least common genital-type leiomyoma, arising from the dartoic muscle cell of the nipple. Histologic examination of the lesion is necessary for definitive diagnosis, and these uncommon tumors can pose a diagnostic challenge. We describe herein a series of six nipple leiomyomas with a spectrum of histologic appearances.
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Affiliation(s)
- Phoebe Hammer
- Department of Pathology, Oregon Health & Science University, Portland, Oregon
| | - Kevin White
- Department of Dermatology, Oregon Health & Science University, Portland, Oregon
| | - Stephanie Mengden
- Department of Dermatology, Oregon Health & Science University, Portland, Oregon
| | - Vessy Korcheva
- Department of Dermatology, Oregon Health & Science University, Portland, Oregon
| | - Philipp W Raess
- Department of Pathology, Oregon Health & Science University, Portland, Oregon
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7
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Hammer P, Litvack D, Saul JP. Interpreting Open- and Closed-Loop Transfer Relations Between Cardiorespiratory Parameters: Lessons Learned from a Computer Model of Beat-to-Beat Cardiovascular Regulation. Methods Inf Med 2018. [DOI: 10.1055/s-0038-1636866] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Abstract:A computer model of cardiovascular control has been developed based on the response characteristics of cardiovascular control components derived from experiments in animals and humans. Results from the model were compared to those obtained experimentally in humans, and the similarities and differences were used to identify both the strengths and inadequacies of the concepts used to form the model. Findings were confirmatory of some concepts but contrary to some which are firmly held in the literature, indicating that understanding the complexity of cardiovascular control probably requires a combination of experiments and computer models which integrate multiple systems and allow for determination of sufficiency and necessity.
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8
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Moura Souza F, Parreira LS, Hammer P, Batista BL, Santos MC. Niobium: a promising Pd co-electrocatalyst for ethanol electrooxidation reactions. J Solid State Electrochem 2017. [DOI: 10.1007/s10008-017-3802-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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9
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Hammer P, Bockelmann W, Hoffmann W. Fate of Listeria innocua during production and ripening of smeared hard cheese made from raw milk. J Dairy Sci 2017; 100:7846-7856. [PMID: 28755934 DOI: 10.3168/jds.2017-12823] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 06/05/2017] [Indexed: 11/19/2022]
Abstract
The fate of 2 different Listeria innocua strains was analyzed during the production and ripening of smeared raw milk Greyerzer cheese (Gruyère). These strains were used as surrogates for the pathogenic Listeria monocytogenes, as they are physiologically very similar. Bacterial cells were added to the cheese milk at levels of 105 cfu/mL. During the first 24 h of cheese making, the number of the test strains decreased to a level of below 102 cfu/g. Obviously, the cooking temperature of 56°C and the subsequent slight temperature decrease to 50°C within 70 min contributed to a distinct reduction of Listeria counts. The counts in the cheese cores did not exceed 103 cfu/g within 12 wk of cheese ripening and Listeria was not detectable after 24 wk. In contrast to the cores of the cheeses of the 4 batches in this study, their rinds always contained a high listerial load of approximately 106 to 108 cfu/g throughout the entire ripening period. The smeared surface showed an increase of pH to alkaline values, corresponding to smear microbiota development. Coryneforms and Staphylococcus counts were stable at >107 cfu/cm2 over 175 d, whereas yeast counts decreased to about 105 cfu/cm2 at the end of ripening. The study shows that the smear culture had no noticeable anti-listerial potential. When removing the rind or portioning such smeared cheese loaves with a cutting device, a postprocess contamination of the core might occur, thus presenting a major hygienic risk.
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Affiliation(s)
- P Hammer
- Department of Safety and Quality of Milk and Fish Products, Max Rubner-Institut, 24103 Kiel, Germany
| | - W Bockelmann
- Department of Microbiology and Biotechnology, Max Rubner-Institut, 24103 Kiel, Germany
| | - W Hoffmann
- Department of Safety and Quality of Milk and Fish Products, Max Rubner-Institut, 24103 Kiel, Germany.
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10
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Bouget YH, Cosimi M, Hammer P, Humbert G, Lyon F, Martini M. Physics Performances of a Heterogeneous Fast Reactor Core Concept Studied in MASURCA. NUCL TECHNOL 2017. [DOI: 10.13182/nt79-a32238] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Y. H. Bouget
- Commissariat à l’Energie Atomique Centre d’Etudes Nucléaires de Cadarache, B.P. No. 1 13115 Saint Paul les Durance, France
| | - M. Cosimi
- Comitato Nazionale per l’Energia Nucleare Centro di Studi Nucleari della Casaccia, 00100 Rome, Italy
| | - P. Hammer
- Commissariat à l’Energie Atomique Centre d’Etudes Nucléaires de Cadarache, B.P. No. 1 13115 Saint Paul les Durance, France
| | - G. Humbert
- Commissariat à l’Energie Atomique Centre d’Etudes Nucléaires de Cadarache, B.P. No. 1 13115 Saint Paul les Durance, France
| | - F. Lyon
- Commissariat à l’Energie Atomique Centre d’Etudes Nucléaires de Cadarache, B.P. No. 1 13115 Saint Paul les Durance, France
| | - M. Martini
- Comitato Nazionale per l’Energia Nucleare Centro di Studi Nucleari della Casaccia, 00100 Rome, Italy
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11
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Simas PS, Antonin VS, Parreira LS, Hammer P, Silva FL, Kronka MS, Valim RB, Lanza MRV, Santos MC. Carbon Modified with Vanadium Nanoparticles for Hydrogen Peroxide Electrogeneration. Electrocatalysis (N Y) 2017. [DOI: 10.1007/s12678-017-0366-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [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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12
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Jakimowicz T, Szmidt J, Hammer P, Witek G, Nazarewski S. T-Branch in Thoraco-abdominal Aneurysm Treatment. Eur J Vasc Endovasc Surg 2016. [DOI: 10.1016/j.ejvs.2016.07.029] [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: 10/21/2022]
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13
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Hammer P. WE-AB-204-04: D&I in Physics. Med Phys 2016. [DOI: 10.1118/1.4957716] [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: 11/07/2022] Open
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14
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Hammer P, Richter E, Rüsch-Gerdes S, Walte HGC, Matzen S, Kiesner C. Inactivation of Mycobacterium bovis ssp. caprae in high-temperature, short-term pasteurized pilot-plant milk. J Dairy Sci 2015; 98:1634-9. [DOI: 10.3168/jds.2014-8939] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Accepted: 11/25/2014] [Indexed: 11/19/2022]
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15
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Harb SV, Santos FCD, Caetano BL, Pulcinelli SH, Santilli CV, Hammer P. Structural properties of cerium doped siloxane–PMMA hybrid coatings with high anticorrosive performance. RSC Adv 2015. [DOI: 10.1039/c4ra15974h] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Novel environmentally compliant Ce(iv) doped siloxane–PMMA coatings exhibiting dense cross-linked structure, high thermal stability, unique anticorrosive performance and self-healing ability.
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Affiliation(s)
- S. V. Harb
- Instituto de Química
- UNESP-Univ Estadual Paulista
- 14800-900 Araraquara
- Brazil
| | - F. C. dos Santos
- Instituto de Química
- UNESP-Univ Estadual Paulista
- 14800-900 Araraquara
- Brazil
| | - B. L. Caetano
- Instituto de Química
- UNESP-Univ Estadual Paulista
- 14800-900 Araraquara
- Brazil
| | - S. H. Pulcinelli
- Instituto de Química
- UNESP-Univ Estadual Paulista
- 14800-900 Araraquara
- Brazil
| | - C. V. Santilli
- Instituto de Química
- UNESP-Univ Estadual Paulista
- 14800-900 Araraquara
- Brazil
| | - P. Hammer
- Instituto de Química
- UNESP-Univ Estadual Paulista
- 14800-900 Araraquara
- Brazil
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Peng S, Hummerjohann J, Stephan R, Hammer P. Erratum to “Short communication: Heat resistance of Escherichia coli strains in raw milk at different subpasteurization conditions” (J. Dairy Sci. 96:3543–3546). J Dairy Sci 2014. [DOI: 10.3168/jds.2014-97-10-6623] [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: 11/19/2022]
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17
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Moore G, Hammer P, Peters M. An intestinal gap‐junction protein is needed for normal acetylcholine response in
Caenorhabditis elegans
(1129.8). FASEB J 2014. [DOI: 10.1096/fasebj.28.1_supplement.1129.8] [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: 11/11/2022]
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18
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Hammer P, Kiesner C, Walte HGC. Short communication: Effect of homogenization on heat inactivation of Mycobacterium avium subspecies paratuberculosis in milk. J Dairy Sci 2014; 97:2045-8. [DOI: 10.3168/jds.2013-7361] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Accepted: 12/10/2013] [Indexed: 11/19/2022]
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19
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Mauline L, Gressier M, Roques C, Hammer P, Ribeiro SJL, Caiut JMA, Menu MJ. Bifunctional silica nanoparticles for the exploration of biofilms of Pseudomonas aeruginosa. Biofouling 2013; 29:775-788. [PMID: 23805884 DOI: 10.1080/08927014.2013.798866] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Luminescent silica nanoparticles are frequently employed for biotechnology applications mainly because of their easy functionalization, photo-stability, and biocompatibility. Bifunctional silica nanoparticles (BSNPs) are described here as new efficient tools for investigating complex biological systems such as biofilms. Photoluminescence is brought about by the incorporation of a silylated ruthenium(II) complex. The surface properties of the silica particles were designed by reaction with amino-organosilanes, quaternary ammonium-organosilanes, carboxylate-organosilanes and hexamethyldisilazane. BSNPs were characterized extensively by DRIFT, (13)C and (29)Si solid state NMR, XPS, and photoluminescence. Zeta potential and contact angle measurements exhibited various surface properties (hydrophilic/hydrophobic balance and electric charge) according to the functional groups. Confocal laser scanning microscopy (CLSM) measurements showed that the spatial distribution of these nanoparticles inside a biofilm of Pseudomonas aeruginosa PAO1 depends more on their hydrophilic/hydrophobic characteristics than on their size. CLSM observations using two nanosized particles (25 and 68 nm) suggest that narrow diffusion paths exist through the extracellular polymeric substances matrix.
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Affiliation(s)
- L Mauline
- Centre Interuniversitaire de Recherche et de l'Ingénierie des Matériaux, UMR-CNRS 5085, Université Paul Sabatier, Toulouse cedex 9, France
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Peng S, Hummerjohann J, Stephan R, Hammer P. Short communication: heat resistance of Escherichia coli strains in raw milk at different subpasteurization conditions. J Dairy Sci 2013; 96:3543-6. [PMID: 23548287 DOI: 10.3168/jds.2012-6174] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Accepted: 02/11/2013] [Indexed: 11/19/2022]
Abstract
A commonly applied treatment of raw milk to reduce bacterial loads is the short-time application of heat at subpasteurization levels under continuous flow, generally referred to as thermization, because this method retains some of the beneficial properties of raw milk. In a previous study, Escherichia coli strains exhibiting increased thermotolerance were found, demanding investigations into their ability to survive thermization. Nine E. coli strains, including 4 Shiga toxin-producing E. coli (STEC) strains, were investigated for their reduction during a thermization treatment in raw milk using a pilot-plant pasteurizer to reflect typically applied commercial conditions. Six of the 9 E. coli strains, including the 4 STEC strains, were similarly inactivated at 60, 62.5, and 65°C, whereas increased thermotolerance was observed for 3 E. coli strains. All strains were reduced to <2 log10 at 60 and 62.5°C within 25s. At 65°C, 6 of 9 E. coli strains were reduced by at least 5 log10 after 25s, whereas at 67.5°C, such a reduction was observed for 8 strains. A much higher thermotolerance was found for E. coli strain FAM21805. For some E. coli strains, time-temperature combinations above 65°C were required to obtain a substantial reduction during a thermization treatment.
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Affiliation(s)
- S Peng
- Institute for Food Safety and Hygiene, University of Zurich, 8057 Zurich, Switzerland
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21
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Peng S, Hoffmann W, Bockelmann W, Hummerjohann J, Stephan R, Hammer P. Fate of Shiga toxin-producing and generic Escherichia coli during production and ripening of semihard raw milk cheese. J Dairy Sci 2013; 96:815-23. [DOI: 10.3168/jds.2012-5865] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Accepted: 10/02/2012] [Indexed: 11/19/2022]
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22
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Jacobs C, Braun P, Hammer P. Reservoir and routes of transmission of Enterobacter sakazakii (Cronobacter spp.) in a milk powder-producing plant. J Dairy Sci 2011; 94:3801-10. [DOI: 10.3168/jds.2011-4318] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 04/10/2011] [Indexed: 11/19/2022]
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23
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Tonoli S, Scotti V, Bertoni F, Saiani F, Spiazzi L, Buonamici FB, Bastiani P, Marrazzo L, Meattini I, Amichetti M, Schwarz M, Guidi G, Hammer P, Magrini S. 277 oral ADJUVANT RADIOTHERAPY AFTER EXTRAPLEURAL PNEUMONECTOMY FOR MESOTHELIOMA. PROSPECTIVE ANALYSIS OF A MULTI-ISTITUTIONAL SERIES. Radiother Oncol 2011. [DOI: 10.1016/s0167-8140(11)70399-1] [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: 11/15/2022]
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24
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Sill B, Roy N, Hammer P, Knappe D, Triedman J, Sigg D, Reichenspurner H, Cowan D. Ovine model of pediatric complete heart block. Thorac Cardiovasc Surg 2011. [DOI: 10.1055/s-0030-1269399] [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: 10/18/2022]
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25
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Affiliation(s)
- A. Helmbold
- a Department of Photoelectrochemistry and New Materials , Institute for Solar Energy Research/GmbH , Sokelantstr. 5, D-30165 , Hannover , Germany
| | - P. Hammer
- a Department of Photoelectrochemistry and New Materials , Institute for Solar Energy Research/GmbH , Sokelantstr. 5, D-30165 , Hannover , Germany
| | - J. U. Thiele
- a Department of Photoelectrochemistry and New Materials , Institute for Solar Energy Research/GmbH , Sokelantstr. 5, D-30165 , Hannover , Germany
| | - K. Rohwer
- a Department of Photoelectrochemistry and New Materials , Institute for Solar Energy Research/GmbH , Sokelantstr. 5, D-30165 , Hannover , Germany
| | - D. Meissner
- a Department of Photoelectrochemistry and New Materials , Institute for Solar Energy Research/GmbH , Sokelantstr. 5, D-30165 , Hannover , Germany
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26
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Abstract
BACKGROUND Gastrin exerts trophic effects on the gastric mucosa by mechanisms not yet completely elucidated. Our aim was to localize the cholecystokinin-2 (CCK2) receptor in epithelial cells of foetal and adult rat stomachs in order to determine the cell types that are directly affected by gastrin. METHODS Gastric tissue was subjected to indirect double immunofluorescence staining with antiserum against the C-terminal decapeptide of the CCK2 receptor and antibodies against 5' bromo-2-deoxyuridine, which had been injected into the rats I h before they were killed, the acid pump H,K-ATPase, the membrane-cytoskeletal linker ezrin, pepsin/pepsinogen or histidine decarboxylase. RESULTS Undifferentiated foetal gastric epithelial cells expressed CCK2 receptors, whereas stem cells of adult gastric glands did not exhibit immunoreactivity. However, other epithelial cells in the progenitor zone of adult gastric glands did express CCK2 receptors. Some of these cells were faintly stained for H,K-ATPase; pepsin/pepsinogen was also detected in this region. Parietal cells in the isthmus/pit region of the glands contained ezrin, and some showed weak immunoreactivity for the CCK2 receptor. As expected, enterochromaffin-like cells also expressed CCK2 receptors. CONCLUSION Our findings are consistent with the hypothesis that a CCK2 receptor mediates direct effects of gastrin on gastric epithelial cells during both stomach organogenesis and adult life.
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Affiliation(s)
- K Tømmerås
- Dept of Biomedicine and Surgery, Faculty of Health Sciences, Linköping University, Sweden.
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27
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Elsner HA, Himmel A, Steitz M, Hammer P, Schmitz G, Ballas M, Blasczyk R. HLA-B*3531, a hybrid of B35 and B61, implications for diagnostic approaches to alleles with complex ancestral compositions. Tissue Antigens 2002; 60:95-7. [PMID: 12366790 DOI: 10.1034/j.1399-0039.2002.600114.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The serological characterization of allelic variants that have been generated by large-scale interallelic recombination events indicates which residues may be involved in the formation of epitopes crucial for serological recognition. The allelic product of HLA-B*3531 is composed of B35 in its alpha1 domain and of B61(40) in its alpha2 domain. Both specificities are only weakly detectable with available sera. Allelic products with 'mixed' serology also represent a challenge to DNA-based HLA typing methods, as only the sequence motif of one ancestral allele may be recognized. In this case the hidden specificity would not be considered in the matching process and might not be recognized as an antigen 'unacceptable' to the recipient.
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Affiliation(s)
- H-A Elsner
- Department of Transfusion Medicine, Hannover Medical School, Germany
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28
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Melchior D, Hammer P, Fimmers R, Schüller H, Albers P. Long term results and morbidity of paraaortic compared with paraaortic and iliac adjuvant radiation in clinical stage I seminoma. Anticancer Res 2001; 21:2989-93. [PMID: 11712799] [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: 02/22/2023]
Abstract
BACKGROUND Radiotherapy is accepted as standard adjuvant treatment for low-stage seminoma and results in excellent survival rates. The optimal radiation field for stage I seminoma, however, is still being discussed. PATIENTS AND METHODS In a retrospective study we evaluated long-term results concerning survival, relapse-pattern, and acute and chronic toxicity in patients receiving adjuvant radiotherapy of the paraaortic and ipsilateral iliac lymph nodes (hockey-stick, HS) versus radiotherapy of the paraaortic lymph nodes only (PA). From 1979-1997, 129 patients (median age 32 years) in clinical stage I received adjuvant radiotherapy. Eighty-seven patients were treated with 36 Gy to the HS field and 42 patients were treated with a median of 28 Gy to the PA field. RESULTS With a median follow-up of 7.7 years (HS) and 5.2 years (PA) the relapse rate was 3.4% and 2.4%, respectively. There was no abdominal or pelvic recurrence in either group. Radiotherapy was well tolerated in both groups. No significant difference in acute or chronic toxicity was noted. However, lower gastrointestinal tract toxicities and myelotoxicities appeared less frequent in the PA group. Second malignancies only occurred in the HS group. Overall survival in the HS and PA group was 96.6% and 100%, respectively. No patient died of seminoma. CONCLUSION With paraaortic radiotherapy only, long-term disease-specific survival was excellent. Decreased risk of acute toxicity and of second malignancies are potential benefits of the reduced radiation field.
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Affiliation(s)
- D Melchior
- Department of Urology, Bonn University, Germany.
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29
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Teufel P, Hammer P. [Which zoonosis is it?]. Dtsch Tierarztl Wochenschr 1999; 106:311-8. [PMID: 10488634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
Starting from the definition for zoonoses according to EU directive 92/117 EEC a brief and mainly tabulated summary is given on the occurrence of zoonoses worldwide and in Germany and related factors.
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30
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Christoffersen GR, Christensen LH, Hammer P, Vang M. The class I metabotropic glutamate receptor antagonist, AIDA, improves short-term and impairs long-term memory in a spatial task for rats. Neuropharmacology 1999; 38:817-23. [PMID: 10465685 DOI: 10.1016/s0028-3908(99)00008-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [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: 11/20/2022]
Abstract
Effects of the class I selective metabotropic glutamate receptor antagonist, 1-aminoindan-1,5-dicarboxylic acid (AIDA), on spatial procedural learning and episodic short-term memory of rats were investigated in an appetitively reinforced 3-choice delayed match-to-position task. First, an acute intraperitoneal injection of AIDA (2 mg/kg) was given 20 min before a single training session of 20 trials using repeated reward position in one alcove out of three. AIDA caused facilitated short-term acquisition within such a session compared to saline treated controls. Secondly, injections were given before each of ten sessions (48 h intervals) also using constant reward position. The results showed AIDA induced inhibition of procedural between-session acquisition. Finally, the use of reward positions in a non-repetitive but trial-specific version of the 3-choice test revealed a facilitating effect of AIDA on episodic short-term memory.
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Affiliation(s)
- G R Christoffersen
- Neuroscience Centre for Cognition and Memory, August Krogh Institute, University of Copenhagen, Denmark.
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31
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Hammer P, Litvack D, Saul JP. Interpreting open- and closed-loop transfer relations between cardiorespiratory parameters: lessons learned from a computer model of beat-to-beat cardiovascular regulation. Methods Inf Med 1997; 36:237-40. [PMID: 9470367] [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: 02/06/2023]
Abstract
A computer model of cardiovascular control has been developed based on the response characteristics of cardiovascular control components derived from experiments in animals and humans. Results from the model were compared to those obtained experimentally in humans, and the similarities and differences were used to identify both the strengths and inadequacies of the concepts used to form the model. Findings were confirmatory of some concepts but contrary to some which are firmly held in the literature, indicating that understanding the complexity of cardiovascular control probably requires a combination of experiments and computer models which integrate multiple systems and allow for determination of sufficiency and necessity.
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Affiliation(s)
- P Hammer
- Boston University, Children's Hospital, Department of Cardiology, Harvard Medical School, MA, USA.
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Pettersson B, Lembke F, Hammer P, Stackebrandt E, Priest FG. Bacillus sporothermodurans, a new species producing highly heat-resistant endospores. Int J Syst Bacteriol 1996; 46:759-64. [PMID: 8782686 DOI: 10.1099/00207713-46-3-759] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Bacteria that differentiate into highly heat-resistant endospores (HHRS strains) may survive ultrahigh-temperature treatment of milk and germinate in the final product. They do not noticeably spoil the milk and are nonpathogenic. The complete (>96%) 16S rRNA genes from three HHRS strains were identical, and phylogenetic analysis placed them alongside Bacillus firmus in the B. megaterium group of the genus Bacillus. Moreover, the approximately 550 nucleotides between regions U2 and U5 were invariant for seven HHRS strains. However, three cloned 16S rRNA genes from one HHRS strain, M215, showed marked size and sequence variations within the V1 and V2 regions. DNA reassociation assays confirmed the distinction between a reference HHRS strain and closely related members of the B. megaterium group, notably, B. firmus (30%), B. benzoevorans (28%), and B. circulans (20%). Ribotyping and pyrolysis mass spectrometry both indicated that the HHRS strains belong to a homogeneous, species-ranked taxon, an exception being strain TP1248, which is slightly atypical. The HHRS strains are unusual in that they grow poorly, if at all, on nutrient agar; good growth is obtained on brain heart infusion agar. On subculture, most HHRS strains form long, filamentous rods which stain unevenly in the Gram reaction. They are strictly aerobic and do not produce acid from sugars. We propose the name Bacillus sporothermodurans for these bacteria, which are phenotypically and phylogenetically distinct from other Bacillus species. The type strain is M215 (= DSMZ 10599).
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Affiliation(s)
- B Pettersson
- Department of Biochemistry and Biotechnology, Royal Institute of Technology, Stockholm, Sweden
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35
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Berg C, Hammer P. [Metal-free restoration techniques. Pin-supported by In-Ceram]. Dent Labor (Munch) 1992; 40:1199-202. [PMID: 1451869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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37
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Miny P, Hammer P, Schloo R, Horst J, Tercanli S, Gerlach B, Holzgreve W. [Prenatal diagnosis with chorionic villi and placenta puncture biopsy in the 1st to 3d trimester of pregnancy: diagnostic value of chromosome studies]. Geburtshilfe Frauenheilkd 1991; 51:694-703. [PMID: 1743468 DOI: 10.1055/s-2007-1023818] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [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: 12/28/2022] Open
Abstract
Chorionic villus sampling and placental biopsies became established diagnostic alternatives to amniocentesis worldwide during the 80's. Safety and accuracy are the most important criteria for the evaluation of these newer techniques as compared to amniocentesis. We report on our experience with more than 3400 chromosome analyses between 1985 and 1990 from first to third trimester of pregnancy in a single centre. Most obvious is the higher frequency of mosaicism, which is often, but not always confined to the placenta. Mosaicism accounts for the overwhelming majority of all discrepant (so-called false negative or false positive) cytogenetic findings. The most important prerequisites for diagnostic accuracy of chromosome analyses are meticulous separation of villi immediately after the sampling procedure as well as simultaneous use of direct preparation and cell culture. If mosaicism is not taken as sound evidence for foetal aneuploidy, the accuracy of cytogenetic diagnoses after chorionic villus sampling and placental biopsies is in the same range as the one after amniocentesis.
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Affiliation(s)
- P Miny
- Institut für Humangenetik der Westfälischen Wilhelms-Universität zu Münster
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Miny P, Hammer P, Gerlach B, Tercanli S, Horst J, Holzgreve W, Eiben B. Mosaicism and accuracy of prenatal cytogenetic diagnoses after chorionic villus sampling and placental biopsies. Prenat Diagn 1991; 11:581-9. [PMID: 1766934 DOI: 10.1002/pd.1970110815] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.5] [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: 12/28/2022]
Abstract
Discrepant chromosome findings in placenta and fetus (false negative and false positive) after chorionic villus sampling (CVS) are mainly due to confined mosaicism. Non-mosaic normal or abnormal chromosome counts after direct preparation and culture nearly always correctly reflect the fetal chromosome constitution. False-negative results have almost exclusively been restricted to cytotrophoblast cells not representing a fetal chromosome abnormality. Diagnosis of placental mosaicism definitely requires an adequate follow-up by amniocentesis, fetal blood sampling, or sonography before a pregnancy is terminated. When direct preparations and cultured cells are used for cytogenetic diagnoses and placental mosaicism is not taken as proof for a chromosomal abnormality in the fetus, CVS is an accurate diagnostic tool.
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Affiliation(s)
- P Miny
- Institut für Humangenetik, University of Münster, Germany
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Abstract
A 37-year-old gravida was referred for CVS because of advanced maternal age. A trisomy 21 was present in all cells after short-term incubation (direct processing (DP)) and long-term culture. According to our policy, a retap was offered for confirmation of the result during the legally required 3-day waiting period between communication of the result and termination of pregnancy. Unexpectedly all cells after DP showed a normal male chromosome complement. Further investigations revealed mosaicism in trophoblast tissue and a normal karyotype in amniotic fluid cells and fetal blood (50 mitoses each). The parents elected to continue the pregnancy after extensive ultrasound examinations did not show suspicious findings. After the birth of a healthy child, cell cultures from ten different placental sites confirmed mosaicism. Four out of 100 mitoses from a lymphocyte culture showed an additional chromosome 21. The child had no dysmorphic features and the development was normal at the age of 10 weeks. This case demonstrates the restricted validity of prenatal cytogenetic analysis in the presence of true fetal mosaicism. It also stresses the benefit of our policy to offer a retap in cases with abnormal cytogenetic results prior to termination of pregnancy which is considered unnecessary by many cytogeneticists.
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Affiliation(s)
- P Hammer
- Institut für Humangenetik, University of Münster, F.R.G
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40
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Berg C, Hammer P. [In-Ceram: unexpected progress in the metal-free ceramic technique]. Dent Labor (Munch) 1990; 38:1043-50. [PMID: 2097217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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41
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Miny P, Karabacak Z, Hammer P, Schulte-Vallentin M, Holzgreve W. Chromosome analyses from urinary sediment: postnatal confirmation of a prenatally diagnosed trisomy 20 mosaicism. N Engl J Med 1989; 320:809. [PMID: 2922032 DOI: 10.1056/nejm198903233201216] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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42
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Ander ME, Zumberge MA, Lautzenhiser T, Parker RL, Aiken CL, Gorman MR, Nieto MM, Cooper AP, Ferguson JF, Fisher E, McMechan GA, Sasagawa G, Stevenson JM, Backus G, Chave AD, Greer J, Hammer P, Hansen BL, Hildebrand JA, Kelty JR, Sidles C, Wirtz J. Test of Newton's inverse-square law in the Greenland ice cap. Phys Rev Lett 1989; 62:985-988. [PMID: 10040395 DOI: 10.1103/physrevlett.62.985] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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43
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Hammer P, Steiner LA. Specificity and heterocliticity of rabbit antisera to the 2,4-dinitrophenyl determinant. The Journal of Immunology 1982. [DOI: 10.4049/jimmunol.128.1.343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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44
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Hammer P, Steiner LA. Specificity and heterocliticity of rabbit antisera to the 2,4-dinitrophenyl determinant. J Immunol 1982; 128:343-50. [PMID: 6172486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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45
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Hammer P, Benedek GB. The effect of naturally occurring cellular constituents on phase separation and opacification in calf lens nuclear homogenates. Curr Eye Res 1982; 2:809-14. [PMID: 7187638 DOI: 10.3109/02713688209020016] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
We have measured the change in the phase separation temperature, Tc, in calf nuclear homogenate produced by a variety of naturally occurring cellular constituents. For all of the compounds studied, increasing concentrations of test compound were found to lower Tc. Phosphorylated nucleotides had the greatest effect, lowering Tc by 165-305 degrees/mole of test compound. Reduced and oxidized glutathione reduced Tc by 69 and 100 degrees C/mole, respectively. Smaller effects were observed for amino and ascorbic acids and sugars. The pH of the homogenate was also found to affect Tc. In the normal lens, the concentration of each of these constituents is small. Therefore, for each individual component, the cataract associated decrease in concentration is insufficient to produce the large increase in Tc that has been observed during cataractogenesis in some model systems. However, the superposition of the effects of changes in many cellular constituents (including pH and hydration) could possible produce a change in Tc more consistent with the experimentally observed one. In support of this, we have found that combinations of test compound have an additive effect on the Tc of the nuclear homogenate.
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Vitti JA, Felten LD, Galluzzo NG, Otter JM, Brittingham JC, Lineberry MJ, McFarlane HF, Collins PJ, Carpenter SG, Barthold WP, Beitel JC, Bouget YH, Cosimi M, Hammer P, Humbert G, Lyon F, Martini M, Bailey HS, Lu YS, Beslu P, Frejaville G, Jeanson P, Garrett PM, Shaw RA, Murata F, Kato K, Tomizawa F, Sumida I, MacEwen SR, Causey AR, Peelle E, Bierman SR, Durst BM, Clayton ED, Scherpelz RI, Kerr HT, Tsoulfanidis N, Jankhah MH, Hall MM, Lee BWT, Levine SH, Jester WA, LeVert FE, Mosteller RD, Andrews WM, Ozer O, Eieh WJ. Authors. NUCL TECHNOL 1979. [DOI: 10.13182/nt79-a32233] [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: 11/12/2022]
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48
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Hammer P. Image building in the eye of a hurricane. Assoc Soc Manager 1978; 10:57-60, 144. [PMID: 10305992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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49
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Hammer P. Determining patient norms. Respir Ther 1977; 7:59-60. [PMID: 10236556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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50
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Hammer P. When crises get the upper hand. Respir Ther 1976; 6:19-21. [PMID: 1029038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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