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Klein AK, Dietzel A. Microfluidic Systems for Antimicrobial Susceptibility Testing. Adv Biochem Eng Biotechnol 2021; 179:291-309. [PMID: 33851232 DOI: 10.1007/10_2021_164] [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] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Human health is threatened by the spread of antimicrobial resistance and resulting infections. One reason for the resistance spread is the treatment with inappropriate and ineffective antibiotics because standard antimicrobial susceptibility testing methods are time-consuming and laborious. To reduce the antimicrobial susceptibility detection time, minimize treatments with empirical broad-spectrum antibiotics, and thereby combat the further spread of antimicrobial resistance, faster and point-of-care methods are needed. This requires many different research approaches. Microfluidic systems for antimicrobial susceptibility testing offer the possibility to reduce the detection time, as small sample and reagent volumes can be used and the detection of single cells is possible. In some cases, the aim is to use human samples without pretreatment or pre-cultivation. This chapter first provides an overview of conventional detection methods. It then presents the potential of and various current approaches in microfluidics. The focus is on microfluidic methods for phenotypic antimicrobial susceptibility testing.
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Affiliation(s)
- Ann-Kathrin Klein
- Institute of Microtechnology Technische Universität Braunschweig, Braunschweig, Germany
| | - Andreas Dietzel
- Institute of Microtechnology Technische Universität Braunschweig, Braunschweig, Germany.
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Klein AK, Laug EP, Datta PR, Watts JO, Chen JT. Metabolites: Reductive Dechlorination of DDT to DDD and Isomeric Transformation of o,p’-DDT to p,p’-DDT In Vivo. J AOAC Int 2020. [DOI: 10.1093/jaoac/47.6.1129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Abstract
Feeding p,p’-DDT and o,p’-DDT separately at a level of 50 ppm in the diet of rats causes reductive dechlorination of DDT to DDD in the liver. No DDD was found in the fat. DDE is not involved in the metabolic pathway. Feeding o,p’-DDT yields evidence of isomeric conversion to p,p’-DDT in the fat stores. The proportion of the p,p’-DDT found to the o,p’-isomer observed is approximately 7:1.
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Affiliation(s)
- A K Klein
- Food and Drug Administration, Washington, D.C. 20204
| | - E P Laug
- Food and Drug Administration, Washington, D.C. 20204
| | - P R Datta
- Food and Drug Administration, Washington, D.C. 20204
| | - J O Watts
- Food and Drug Administration, Washington, D.C. 20204
| | - J T Chen
- Food and Drug Administration, Washington, D.C. 20204
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Abstract
Microfluidic systems enable manipulating fluids in different functional units which are integrated on a microchip. This chapter describes the basics of microfluidics, where physical effects have a different impact compared to macroscopic systems. Furthermore, an overwiew is given on the microfabrication of these systems. The focus lies on clean-room fabrication methods based on photolithography and soft lithography. Finally, an outlook on advanced maskless micro- and nanofabrication methods is given. Special attention is paid to laser structuring processes.
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Affiliation(s)
- Ann-Kathrin Klein
- Institute of Microtechnology Technische Universität Braunschweig, Braunschweig, Germany
| | - Andreas Dietzel
- Institute of Microtechnology Technische Universität Braunschweig, Braunschweig, Germany.
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Klein AK, Horneff G. [Improvement of sensoneurinal hearing loss in a patient with Muckle-Wells syndrome treated with anakinra]. Klin Padiatr 2010; 222:266-8. [PMID: 20135584 DOI: 10.1055/s-0029-1239527] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Muckle Wells syndrome is an autoinflammatory disease in the group of cryopyrin associated periodic syndromes (CAPS). We report the case of an 8 year old girl with MWS who presented with remitting fever, urticaria, remitting coxitis, osteitis, bilateral uveitis anterior, elevated levels of C-reactive protein (CRP) and Serum amyloid A (SAA) and progressive sensoneurinal hearing loss. After starting treatment with anakinra, clinical symptoms dissolved almost completely for about two years now. CRP and SAA levels normalized quickly and sustained and as a consequence the risk of amyloidosis may be minimized. Notable is the complete recovery from sensoneurinal hearing loss merely two months after start of treatment. This brings up questions about pathophysiology of sensoneurinal hearing loss in MWS and emphasizes the benefits of an early diagnosis, as an early start of treatment possibly reduces long-term damage.
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Affiliation(s)
- A K Klein
- Asklepios Kinderklinik Sankt Augustin, Zentrum für Allgemeine Pädiatrie und Neonatologie, Arnold-Janssen-Strasse 29, Sankt Augustin, Germany.
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Klein AK, Patel DD, Gooding ME, Sempowski GD, Chen BJ, Liu C, Kurtzberg J, Haynes BF, Chao NJ. T-Cell recovery in adults and children following umbilical cord blood transplantation. Biol Blood Marrow Transplant 2002; 7:454-66. [PMID: 11569891 DOI: 10.1016/s1083-8791(01)80013-6] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
T-cell reconstitution following allogeneic stem cell transplantation may involve thymic education of donor-derived precursors or peripheral expansion of mature T cells transferred in the graft. T cell-receptor excision circles (sjTRECs) are generated within the thymus and identify new thymic emigrants and those that have not divided. We measured quantitative and qualitative immunologic reconstitution and sjTREC levels in adult and pediatric recipients of umbilical cord blood transplants (UCBTs). sjTRECs were detected at normal levels in all children, starting 12 months after transplantation. sjTRECs were not detected until 18 months after transplantation in adults, and then only at a 3-fold lower level than expected for age. We used complementarity-determining region 3 (CDR3) spectratyping to measure changes in T cell-receptor diversity occurring with restoration of thymic function. T-cell repertoires were skewed in adults and children at 12 to 18 months after transplantation but recovered to near-normal diversity at 2 to 3 years post-UCBT. T-cell repertoires appeared more diverse earlier in children (at 1 to 2 years post-UCBT) than in adults (at 3 to 4 years post-UCBT). We conclude that early T-cell recovery after UCBT occurs primarily through peripheral expansion of adoptively transferred donor T cells and results in skewing of the T-cell repertoire. The reappearance of sjTREC-containing cells after UCBT is associated with increasing numbers of phenotypicaly naive T cells, improved mitogen and recall antigen responses, and diversification of the T-cell repertoire. The delay in central T-cell recovery in adults relative to children may be due to differences in thymic function resulting from age-related atrophy, graft-versus-host disease, or the pharmacologic effects of prophylaxis and treatment of graft-versus-host disease.
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Affiliation(s)
- A K Klein
- Department of Medicine and the Human Vaccine Institute, Duke University Medical Center, Durham, North Carolina, USA. aklein2@life span.org
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Abstract
Although current edge-following schemes can be very efficient in determining coronary boundaries, they may fail when the feature to be followed is disconnected (and the scheme is unable to bridge the discontinuity) or branch points exist where the best path to follow is indeterminate. In this paper, we present new deformable spline algorithms for determining vessel boundaries, and enhancing their centerline features. A bank of even and odd S-Gabor filter pairs of different orientations are convolved with vascular images in order to create an external snake energy field. Each filter pair will give maximum response to the segment of vessel having the same orientation as the filters. The resulting responses across filters of different orientations are combined to create an external energy field for snake optimization. Vessels are represented by B-Spline snakes, and are optimized on filter outputs with dynamic programming. The points of minimal constriction and the percent-diameter stenosis are determined from a computed vessel centerline. The system has been statistically validated using fixed stenosis and flexible-tube phantoms. It has also been validated on 20 coronary lesions with two independent operators, and has been tested for interoperator and intraoperator variability and reproducibility. The system has been found to be specially robust in complex images involving vessel branchings and incomplete contrast filling.
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Affiliation(s)
- A K Klein
- Department of Internal Medicine, New England Medical Center, Boston, MA 02111, USA
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Wade MJ, Davis BK, Carlisle JS, Klein AK, Valoppi LM. Environmental transformation of toxic metals. Occup Med 1993; 8:574-601. [PMID: 8272980] [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: 01/29/2023]
Abstract
Because toxicity varies enormously with the chemical state of metals, transformations in the environment control the level of the human health hazard. Important transformation processes include adsorption and desorption from soils and sediments, oxidation and reduction (redox) reactions, biotic metabolism, formation of organic metal compounds, and bioaccumulation. The six metals detailed in this chapter--arsenic, cadmium, chromium, lead, mercury, and selenium--were chosen because of their toxicity, frequency of occurrence at hazardous waste sites, and involvement in environmental contamination.
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Affiliation(s)
- M J Wade
- Department of Toxic Substances Control, California Environmental Protection Agency Sacramento 95812-0806
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Abstract
Cultured Chinese hamster ovary (CHO) cells were exposed to two neurotoxic organophosphates, either sarin (GBI, GBII) at 1.4 X 10(-3) M or soman (GD) at 1.1 and 2.2 X 10(-3) M for 1 h, grown and their metaphase chromosomes scored for sister-chromatid exchanges (SCE). No cytotoxicity was seen with either agent at any dose level tested. Since histograms of SCE per cell showed that they were non-symmetrically arrayed around the mean, the number of SCEs were analyzed by using the nonparametric tests, Mann-Whitney and Kruskall-Wallis. Agents GBI and GBII did not show any significant increase in SCE over baseline. On the other hand, GD demonstrated a statistically significant increase in SCE with and without metabolic activation. Ethyl methanesulfonate (EMS) alone at 5 X 10(-3) M and cyclophosphamide (CP) at 10(-4) M in the presence of rat microsomes (S9) induced a 3- and 8-fold increase in SCE per cell, respectively.
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Affiliation(s)
- M L Nasr
- Laboratory for Energy-Related Health Research, University of California, Davis 95616
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Klein AK, Nasr ML, Goldman M. The effects of in vitro exposure to the neurotoxins sarin (GB) and soman (GD) on unscheduled DNA synthesis by rat hepatocytes. Toxicol Lett 1987; 38:239-49. [PMID: 3660426 DOI: 10.1016/0378-4274(87)90004-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [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: 01/06/2023]
Abstract
Large amounts of the nerve agents, sarin (GB) and soman (GD), are part of the military chemical arsenal and small amounts are on hand in numerous U.S. research laboratories. Thus, there is a potential for accidental occupational exposure to these compounds. As part of a study of mutagenic, reproductive and subchronic effects of these agents, we measured unscheduled DNA repair synthesis in isolated rat hepatocytes after exposure to GBI (stabilized with tributylamine), GBII (stabilized with diisopropylcarbodiimide) or GD. This was done to determine whether these agents or their metabolites directly damage DNA or their related proteins. Each agent was assayed at least once over concentrations ranging from 3.0 X 10(-4) to 2.4 X 10(-3) M for GBI and GBII and 2.3 X 10(-4) to 1.8 X 10(-3) for GD and at least 3 times at 2.4 X 10(-3) M for GBI and GBII and 1.8 X 10(-3) M for GD, added as 20% of the culture medium. In all assays, no increase in the level of DNA synthesis was observed. On the contrary, significant decreases in repair synthesis were seen in hepatocytes exposed to GBI or GBII. The decreases in DNA synthesis seen in response to GD were less marked and not significant. These observations were not related to cell death, since 8 of 10 assays performed showed no significant decrease in the amount of DNA present in cultures exposed to the nerve agents compared to the negative controls. Our results suggest that the agents GBI, GBII and GD may either inhibit the repair of DNA or protect DNA from damage.
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Affiliation(s)
- A K Klein
- Laboratory for Energy-Related Health Research, University of California, Davis 95616
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Dyck JA, Shifrine M, Klein AK, Rosenblatt LS, Kawakami T. Spontaneous cell-mediated cytolysis by peripheral blood cells obtained from whole-body chronically irradiated beagle dogs. Radiat Res 1986; 106:31-40. [PMID: 3515399] [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: 01/06/2023]
Abstract
The level of natural killer (NK) activity of continuously gamma-irradiated (whole body) beagle dogs and their nonirradiated controls was studied. For analytical purposes, irradiated dogs were segregated into groups according to their clinical status: clinically normal, hypocellular, or with acute non-lymphocytic leukemia. Since unirradiated control animals exhibited a wide range of NK responses, the data from each irradiated animal were compared to its own age-matched or litter-matched unirradiated control. Of the eight clinically normal irradiated dogs (median = 146% activity of control) only one animal had a NK activity lower than that of its control. The hypocellular group (n = 5, median = 21.8% of control) and the leukemic group (n = 4, median = 52.5% of control) each contained one responder with higher activity than its control. The difference between the percentage of control of the clinically normal and clinically abnormal dogs was found to be significant (P less than 0.05). There is a negative correlation between the NK results obtained and the total accumulated dose of radiation at the time of sampling (correlation coefficient = -0.739, P less than 0.01), suggesting a radiation effect upon natural killer activity, which is evidence by enhancement at lower doses and depression at higher doses of irradiation.
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Klein AK, Dyck JA, Shimizu JA, Stitzel KA, Wilson FD, Cain GR. Effect of continuous, whole-body gamma irradiation upon canine lymphohematopoietic (CFU-GM, CFU-L) progenitors and a possible hematopoietic regulatory population. Radiat Res 1985; 101:332-50. [PMID: 3883396] [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: 01/07/2023]
Abstract
Clonogenic assays for granulocytes-macrophages (CFU-GM) in bone marrow and for T lymphocytes (CFU-L) in peripheral blood were performed on dogs continuously exposed to 60Co irradiation (0.02, 0.04, or 0.11 Gy/day). When decreased numbers of CFU-GM were observed they correlated well with the clinical status of the dogs but were not generally associated with increasing cumulative doses of absorbed irradiation. In clinically normal, irradiated animals, decreased CFU-GM values and myeloid-erythroid ratios were observed, suggesting that chronic irradiation may affect the granulocytic series well before decreased peripheral blood values are seen. In hypocellular dogs the number of CFU-GM were significantly decreased compared to values obtained from control or clinically normal irradiated dogs, while virtually no CFU-GM were observed in the leukemic dogs. Only the CFU-GM values of the hypocellular group showed an association, e.g., a suggestion of an abortive regenerative effort, with increasing absorbed dose. Proliferative capacity of T lymphocytes (CFU-L) was not affected by either increasing absorbed irradiation or the presence of leukemia. D0 values were determined on marrow fibroblastic cells to ascertain whether a radioresistant subpopulation of stromal elements would result from continuous in vivo irradiation. No correlation was found between absorbed dose and increased D0 values. However, seven of eight dogs which developed acute nonlymphocytic leukemia displayed marrow fibroblastic cells with elevated D0 values. These radioresistant marrow fibroblastic cells were assayed for their ability to support normal granulopoiesis and found to be not significantly different from control fibroblasts.
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Greenberg BR, Wilson FD, Woo L, Klein AK, Rosenblatt LS. Increased in vitro radioresistance of bone marrow fibroblastic progenitors (CFU-F) from patients with acute non-lymphocytic leukemia. Leuk Res 1984; 8:267-73. [PMID: 6717067 DOI: 10.1016/0145-2126(84)90150-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The proliferative potential following in vitro irradiation of bone marrow fibroblastic progenitors (CFU-F) derived from four patients with acute nonlymphocytic leukemia (ANLL) and seven nonleukemic subjects was compared. The CFU-F from the ANLL patients were significantly more radioresistant than the CFU-F from the nonleukemic subjects. The increased radioresistance in ANLL patients was evident in both the mean slope of the survival curve (control = -0.385, ANLL = -0.256) and in the Do values (control = 2.68 Gy, ANLL = 4.61 Gy). Thus CFU-F derived from ANLL patients differ from those derived from nonleukemics in both radioresistance and in granulopoietic effects as suggested from previous studies.
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Klein AK, Lynch JA, Dyck JA, Shimizu JA, Fox LA, Stitzel KA. The influence of fibroblast-like cells derived from canine fetal hematopoietic tissues on the regulation of lymphohematopoiesis. Int J Cell Cloning 1984; 2:20-33. [PMID: 6707490 DOI: 10.1002/stem.5530020105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Media conditioned by fibroblast-like cells derived from organs active in fetal lymphohematopoiesis were studied for their effects on adult granulocyte/macrophage colony-forming units (CFU-GM). Fibroblasts from fetal liver produced a factor stimulatory for CFU-GM, whereas fibroblasts from fetal marrow produced a factor inhibitory for CFU-GM which was not completely relieved by adding indomethacin to the assay. Our studies indicated that neither fetal marrow nor fetal liver produced factors affecting lymphocyte colony-forming units (CFU-L). Cell-cell interactions between fibroblast-like cells derived from fetal liver or marrow and normal adult CFU-GM were also studied. We observed that fibroblasts derived from both fetal and adult marrow inhibited colony formation, whereas inhibition in the presence of fetal liver fibroblasts was minimal. Loss of inhibitory activity by a liver fibroblast cell line over repeated passages was seen. Differential analysis of colonies formed above an adherent layer of fetal marrow fibroblasts suggested that these fibroblasts suppress myeloid/macrophage differentiation to a far greater degree than did adult marrow fibroblasts. A role in the regulation of fetal lymphohematopoiesis may be played by stromal fibroblasts.
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Klein AK, Rosenblatt LS, Stitzel KA, Greenberg B, Woo L. In vitro radiation response studies on bone marrow fibroblasts (CFU-F) obtained from normal and chronically irradiated dogs. Leuk Res 1984; 8:473-81. [PMID: 6748731 DOI: 10.1016/0145-2126(84)90088-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The radiation resistance of bone marrow fibroblasts as measured by their proliferative potential was evaluated in chronically irradiated dogs. Bone marrows were obtained from eight dogs that had been chronically irradiated beginning at 21 days of gestation or after birth and eight age-matched controls. Of these irradiated dogs, four were either preleukemic or exhibited frank acute nonlymphocytic leukemia. The other four were clinically normal but demonstrated abnormalities in their marrow that could be attributed to radiation effects and/or other pathologic changes. Fibroblasts from six of the irradiated dogs were significantly more radioresistant than those of their controls. Five of these six dogs subsequently succumbed to hematopathologic disease, while the two irradiated dogs with normal fibroblasts remained clinically normal, suggesting that this observed radioresistance may be linked to the disease process.
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Klein AK, Dyck JA, Stitzel KA, Shimizu J, Fox LA, Taylor N. Characterization of canine fetal lymphohematopoiesis: studies of CFUGM, CFUL, and CFUF. Exp Hematol 1983; 11:263-74. [PMID: 6601584] [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: 01/20/2023]
Abstract
We assayed the colony forming units for granulocyte-macrophages (CFUGM), T-lymphocytes (CFUL) and fibroblasts (CFUF) in the blood, bone marrow, liver and spleen of the canine at 45 and 55 days of gestation and 4 and 30 days post partum. As the number of CFUGM per 5 x 10(5) cells increased in the fetal liver, the number of CFUGM increased in circulating blood, whereas when the number of CFUGM decreased in liver and blood, CFUGM increased in both bone marrow and spleen. This suggests that CFUGM are produced in the liver, are released into the circulation and then transported to the spleen and bone marrow. CFUF studies showed that canine fetal bone marrow and spleen are active sites of fibroblast proliferation, whereas the liver is not. Morphologic examination of colonies derived from concanavalin-A stimulated progenitors ("CFUL") demonstrated that these colonies from fetal tissues and adult bone marrow were not exclusively lymphoid but were also made up of significant numbers of precursors of the myeloid and monocytic series. Lymphocyte stimulation tests (LST) showed the presence of a large population of mitogen-independent dividing cells, suggesting that fetal lymphohematopoiesis may be at least partially under the influence of factors other than those of adult cells.
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Wilson FD, Stitzel KA, Klein AK, Shifrine M, Graham R, Jones M, Bradley E, Rosenblatt LS. Quantitative response of bone marrow colony-forming units (CFU-C and PFU-C) in weanling beagles exposed to acute whole-body gamma irradiation. Radiat Res 1978; 74:289-97. [PMID: 663067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Wilson FD, Konrad PN, Greenberg BR, Klein AK, Walling PA. Cytogenetic studies on bone marrow fibroblasts from a male-female hematopoietic chimera. Evidence that stromal elements in human transplantation recipients are of host type. Transplantation 1978; 25:87-8. [PMID: 341430 DOI: 10.1097/00007890-197802000-00010] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Wolf HG, Shifrine M, Klein AK, Foin AT. Hematologic values for laboratory reared Marmosa mitis. Lab Anim Sci 1971; 21:249-51. [PMID: 4325700] [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: 01/10/2023]
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Klein AK, Link JD. Elimination of Interferences in the Determination of Toxaphene Residues. J AOAC Int 1970. [DOI: 10.1093/jaoac/53.3.524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
The presence of DDT interferes in the GLC method for toxaphene. The interference is overcome by treating the sample extract with cold sulfuric-fuming nitric acids (1 + 1). The acid treatment converts DDT to compounds which do not register on the GLC. Toxaphene is scarcely affected and responds in the usual manner. The interference of various other pesticides is also prevented. The acid treatment also aids the toxaphene colorimetric method by destroying sample organic background. Toxaphene levels below 1.0 ppm can now be determined by the colorimetric method. Chlordane is not removed by the acid treatment and interferes in both the GLC and colorimetric toxaphene methods.
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Affiliation(s)
- A K Klein
- Division of Pesticides, Food and Drug Administration, Washington, D.C. 20204
| | - J D Link
- Division of Pesticides, Food and Drug Administration, Washington, D.C. 20204
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Dailey RE, Walton MS, Beck V, Leavens CL, Klein AK. Excretion, distribution, and tissue storage of a 14C-labeled photoconversion product of 14C-dieldrin. J Agric Food Chem 1970; 18:443-445. [PMID: 5487102 DOI: 10.1021/jf60169a014] [Citation(s) in RCA: 3] [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: 05/21/2023]
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Klein AK, Link JD, Ives NF. Isolation and Purification of Metabolites Found in the Urine of Male Rats Fed Aldrin and Dieldrin. J AOAC Int 1968. [DOI: 10.1093/jaoac/51.4.895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
A procedure for the isolation and purification of aldrin and dieldrin metabolites derived from rat urine is described. The procedure yields enough material of adequate purity to enable the determination of the chemical structure of the metabolites.
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Affiliation(s)
- A K Klein
- Division of Food Chemistry, Bureau of Science, Food and Drug Administration, Washington, D.C. 20204
| | - J D Link
- Division of Food Chemistry, Bureau of Science, Food and Drug Administration, Washington, D.C. 20204
| | - N F Ives
- Division of Food Chemistry, Bureau of Science, Food and Drug Administration, Washington, D.C. 20204
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Mendel JL, Klein AK, Chen JT, Walton MS. Metabolism of DDT and Some Other Chlorinated Organic Compounds by Aerobacter aerogenes. J AOAC Int 1967. [DOI: 10.1093/jaoac/50.4.897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
The micro-organism, Aerobacter aerogenes, reductively dechlorinates o,p'-DDT to o,p'-DDD. The yield is constant for a constant 24-hour incubation period. This metabolic pathway appears to be rather specific for the DDT's, since Perthane is not produced from l,l,l-trichloro-2,2-bis(pethylphenyl) ethane even after long incubation with A. aerogenes. In general, incubation of methoxychlor with the bacterium results in loss of the pesticide: its olefin and the reductively dechlorinated pesticide [ (l,l-dichloro-2,2-bis (p-methoxyphenyl) ethane] are sometimes produced but only after long term incubation. A. aerogenes does not effect the conversion of aldrin to dieldrin.
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Affiliation(s)
- J L Mendel
- Food and Drug Administration, Washington, D.C. 20204
| | - A K Klein
- Food and Drug Administration, Washington, D.C. 20204
| | - J T Chen
- Food and Drug Administration, Washington, D.C. 20204
| | - Mae S Walton
- Food and Drug Administration, Washington, D.C. 20204
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Klein AK, Link JD. Field Weathering of Toxaphene and Chlordane. J AOAC Int 1967. [DOI: 10.1093/jaoac/50.3.586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
Both toxaphene and chlordane are rapidly lost on kale and presumably on other vegetables by weathering. Only trace amounts remain from an initial heavy application after 28 days. During this period the composition of the pesticides changes. With toxaphene, even at low levels, the remaining components appear to be organic chlorine compounds. The revised colorimetric method for toxaphene gives satisfactory results and supplements gas chromatography when the toxaphene level is not lower than 10 ppm or perhaps 5 ppm. The colorimetric method is not applicable at levels of 1 ppm or less. Large amounts of DDT interfere with the proper evaluation of the toxaphene by gas chromatography. Chlordane interferes seriously in both methods
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Affiliation(s)
- A K Klein
- Division of Food Chemistry, Food and Drug Administration, Washington, D.C. 20204
| | - J D Link
- Division of Food Chemistry, Food and Drug Administration, Washington, D.C. 20204
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24
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Klein AK, Watts JO, Damico JN. Electron Capture Gas Chromatography for Determination of DDT in Butter and Some Vegetable Oils. J AOAC Int 1963. [DOI: 10.1093/jaoac/46.2.165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
The use of electron capture gas chromatography makes it possible to determine DDT in 1 g of butter and in 1 g of refined vegetable oils at the 0.1—1.0 ppm level of DDT. The precision is about 90%. The lowest limit for reliable measurements is 0.1 ppm DDT. At 0.05 ppm, DDT is not measured. A variable artifact, having the same retention time as p,p’-DDT, is the limiting factor. The presence of DDT may be confirmed by measuring and identifying DDE formed by alkaline hydrolysis.
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Affiliation(s)
- A K Klein
- Division of Food, Food and Drug Administration, Washington 25, D.C
| | - J O Watts
- Division of Food, Food and Drug Administration, Washington 25, D.C
| | - J N Damico
- Division of Food, Food and Drug Administration, Washington 25, D.C
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25
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Affiliation(s)
- J O Watts
- Division of Food, Food and Drug Administration, Washington 25, D.C
| | - A K Klein
- Division of Food, Food and Drug Administration, Washington 25, D.C
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26
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Klein AK, Gajan RJ. Determination of Pentachloronitrobenzene in Vegetables. J AOAC Int 1961. [DOI: 10.1093/jaoac/44.4.712] [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: 11/13/2022]
Affiliation(s)
- A K Klein
- Division of Food, Fcod and Drug Administration,Washington 25, D.C
| | - R J Gajan
- Division of Food, Fcod and Drug Administration,Washington 25, D.C
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27
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Klein AK. Determination of DDT in Leafy Vegetables. J AOAC Int 1960. [DOI: 10.1093/jaoac/43.3.703] [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: 11/14/2022]
Affiliation(s)
- A K Klein
- Food and Drug Administration, Department of Health, Education, and Welfare, Washington 25, D.C
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28
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Klein AK, Laug EP, Sheehan JD. Report on Extraction Procedures for Chloro-organic Insecticides. J AOAC Int 1959. [DOI: 10.1093/jaoac/42.3.539] [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: 11/12/2022]
Affiliation(s)
- A K Klein
- Food and Drug Administration, Department of Health, Education, and Welfare, Washington 25, D.C
| | - E P Laug
- Food and Drug Administration, Department of Health, Education, and Welfare, Washington 25, D.C
| | - J D Sheehan
- Food and Drug Administration, Department of Health, Education, and Welfare, Washington 25, D.C
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29
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Klein AK. Report on Extraction Procedures for Chloro-organic Pesticides. J AOAC Int 1958. [DOI: 10.1093/jaoac/41.3.551] [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: 11/12/2022]
Affiliation(s)
- A K Klein
- Division of Food, Food and Drug Administration, Department of Health, Education, and Welfare, Washington 25, D.C
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30
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Munsey VE, Mills PA, Klein AK. IV. Findings. E. Cooking Studies. J AOAC Int 1957. [DOI: 10.1093/jaoac/40.1.201] [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: 11/13/2022]
Affiliation(s)
- V E Munsey
- Food and Drug Administration, Washington 25, D. C
| | - P A Mills
- Food and Drug Administration, Washington 25, D. C
| | - A K Klein
- Food and Drug Administration, Washington 25, D. C
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31
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Klein AK, Laug EP, Tighe JF, Ramsey LL, Mitchell LC, Kunze FM. Biological Assay of Endrin in Leafy Vegetables and Its Confirmation By Paper Chromatography. J AOAC Int 1956. [DOI: 10.1093/jaoac/39.1.242] [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: 11/13/2022]
Affiliation(s)
- A K Klein
- Food and Drug Administration, Department of Health, Education, and Welfare, Washington 25, D. C
| | - E P Laug
- Food and Drug Administration, Department of Health, Education, and Welfare, Washington 25, D. C
| | - J F Tighe
- Food and Drug Administration, Department of Health, Education, and Welfare, Washington 25, D. C
| | - L L Ramsey
- Food and Drug Administration, Department of Health, Education, and Welfare, Washington 25, D. C
| | - L C Mitchell
- Food and Drug Administration, Department of Health, Education, and Welfare, Washington 25, D. C
| | - Frieda M Kunze
- Food and Drug Administration, Department of Health, Education, and Welfare, Washington 25, D. C
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32
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Klein AK. Report on Benzene Hexachloride in Foods. J AOAC Int 1953. [DOI: 10.1093/jaoac/36.3.589] [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: 11/14/2022]
Affiliation(s)
- A K Klein
- Food and Drug Administration, Department of Health, Education, and Welfare, Washington, D. C
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33
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Affiliation(s)
- A K Klein
- Food and Drug Administration, Department of Health, Education, and Welfare, Washington, D. C
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34
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Affiliation(s)
- A K Klein
- Food and Drug Administration, Federal Security Agency, Washington, D. C
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35
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Affiliation(s)
- A K Klein
- Food and Drug Administration, Federal Security Agency, Washington 25, D. C
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36
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Affiliation(s)
- A K Klein
- Food & Drug Administration, Federal Security Agency, Washington, D. C
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37
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Affiliation(s)
- A K Klein
- Food and Drug Administration, Federal Security Agency, Washington 25, D. C
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38
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Affiliation(s)
- A K Klein
- U. S. Food and Drug Administration, Federal Security Agency, Washington, D. C
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39
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White WB, Price CW, Klein AK, Wichmann HJ. Soil and Plant Take-up of Selenium from Spraying Orange Groves. J AOAC Int 1946. [DOI: 10.1093/jaoac/29.4.349] [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: 11/14/2022]
Affiliation(s)
- W B White
- U. S. Food and Drug Administration, Federal Security Agency, Washington, D. C
| | - C W Price
- U. S. Food and Drug Administration, Federal Security Agency, Washington, D. C
| | - A K Klein
- U. S. Food and Drug Administration, Federal Security Agency, Washington, D. C
| | - H J Wichmann
- U. S. Food and Drug Administration, Federal Security Agency, Washington, D. C
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40
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Wichmann HJ, Patterson WI, Clifford PA, Klein AK, Claborn HV. The Determination of Ddt as Spray Residue on Fresh Fruit Three Independent Methods. J AOAC Int 1946. [DOI: 10.1093/jaoac/29.2.188] [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: 11/13/2022]
Affiliation(s)
- H J Wichmann
- Food and Drug Administration,** Federal Security Agency, Washington 25, D. C
| | - W I Patterson
- Food and Drug Administration,** Federal Security Agency, Washington 25, D. C
| | - P A Clifford
- Food and Drug Administration,** Federal Security Agency, Washington 25, D. C
| | - A K Klein
- Food and Drug Administration,** Federal Security Agency, Washington 25, D. C
| | - H V Claborn
- Food and Drug Administration,** Federal Security Agency, Washington 25, D. C
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41
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Wichmann HJ, Patterson WI, Clifford PA, Klein AK, Claborn HV. Decomposition and Volatility of Ddt and Some of Its Derivatives. J AOAC Int 1946. [DOI: 10.1093/jaoac/29.2.218] [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: 11/14/2022]
Affiliation(s)
- H J Wichmann
- Food Division,* Food and Drug Administration, Federal Security Agency, Washington 25, D. C
| | - W I Patterson
- Food Division,* Food and Drug Administration, Federal Security Agency, Washington 25, D. C
| | - P A Clifford
- Food Division,* Food and Drug Administration, Federal Security Agency, Washington 25, D. C
| | - A K Klein
- Food Division,* Food and Drug Administration, Federal Security Agency, Washington 25, D. C
| | - H V Claborn
- Food Division,* Food and Drug Administration, Federal Security Agency, Washington 25, D. C
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42
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Affiliation(s)
- A K Klein
- Food and Drug Administration, Federal Security Agency, Washington, D. C
| | - H J Wichmann
- Food and Drug Administration, Federal Security Agency, Washington, D. C
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43
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Affiliation(s)
- A K Klein
- U. S. Food and Drug Administration, Washington, D. C
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44
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Affiliation(s)
- A K Klein
- U. S. Food and Drug Administration, Washington, D. C
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45
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Klein AK, Vorhes FA. Determination of Arsenic. J AOAC Int 1939. [DOI: 10.1093/jaoac/22.1.121] [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: 11/13/2022]
Affiliation(s)
- A K Klein
- U. S. Food and Drug Administration, San Francisco, Calif
| | - F A Vorhes
- U. S. Food and Drug Administration, San Francisco, Calif
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