Post-chemotherapy and cytokine pretreated marrow stromal cell layers suppress hematopoiesis from normal donor CD34+ cells

Marrow stromal layers were used to investigate the potential role of negative regulators produced by the marrow microenvironment as one potential cause of hematopoietic suppression after chemotherapy and cytokines. Stromal layers were established from marrow of normal or prechemotherapy donors and breast cancer patients after hematological recovery from one cycle of 5-fluorouracil, leucovorin, doxorubicin, and cyclophosphamide and GM-CSF or PIXY321 (GM-CSF/IL-3 fusion protein). Normal donor CD34+ cells were placed in contact with stromal layers, and the number of colony-forming units for granulocytes and macrophages (CFU-GM) was determined. There were 25-79% fewer CFU-GM in post-chemotherapy stromal layer cocultures than in no chemotherapy cocultures. With neutralizing antibody to TNF-alpha the number of CFU-GM in no chemotherapy and post-chemotherapy stromal cocultures was, respectively, 96 +/- 7% (n = 5) and 142 +/- 8% (n = 5) of the number with no antibody treatment. PIXY321 and GM-CSF pretreated stromal layers also suppressed production of CFU-GM. Anti-TNF-alpha promoted an increase in CFU-GM numbers from GM-CSF, but not PIXY321, pretreated stromal cocultures. The results demonstrate that post-chemotherapy marrow stromal layers were deficient in supporting in vitro hematopoiesis and suggest that negative regulators induced by chemotherapy and cytokines may be one cause for this defect.     

Mutation analysis of CYP2D6 locus in the Korean population: identification of rare poor metabolizer alleles at the nucleotide level

We conducted studies to determine at what time point an add-on prothrombin time (PT) or activated partial thromboplastin time (APTT) test can be honored on specimens that have been received in the laboratory hours earlier without yielding results with clinically significant differences from those if the test had been performed on the original unstored plasma. PT and APTT tests were performed on blood samples from 20 healthy subjects, 30 patients receiving warfarin, and 30 patients receiving heparin anticoagulation therapy. The tests were performed on plasma prepared initially after the samples were obtained. The same tests were assayed on plasma that had been left on spun-down blood cells at room temperature for 2, 4, and 8 hours. We found that the PT of the majority of plasma samples from healthy subjects and from patients receiving oral anticoagulant therapy tended to become shorter on storage. However, the difference in PT values was small and had no clinical significance. In most cases, the APTT values for the stored plasma from healthy subjects tended to increase with time. Except in one specimen in which the 8-hour add-on APTT was 1.2 seconds longer than the APTT result for the original sample, all others had APTT results less than 1.2 seconds longer than the original values. In patients receiving heparin, the differences in APTT values between the initial and add-on tests were larger than those observed for healthy subjects. However, those differences are not beyond what we would accept for duplicate checks for heparinized samples with high APTT values. Unlike samples from healthy subjects, there was no obvious trend of time-related prolongation of the APTT in heparinized plasma. These results led us to believe that within an 8-hour period and with plasma on spun-down cells at room temperature, add-on tests for PT and APTT could be performed with results similar to what would be obtained from testing unstored samples.     

Nickel biochemistry

We present a method for the determination of the lignan enterolactone in plasma (serum). This compound, produced by intestinal bacteria from matairesinol and secoisolariciresinol in fiber-rich food, is a biomarker related to the intake of a healthy diet. The method is based on time-resolved fluoroimmunoassay using a europium chelate as a label. After synthesis of 5'-O-carboxymethoxyenterolactone the compound is coupled to bovine serum albumin and then used as antigen in immunization of rabbits. The tracer with the europium chelate is synthesized using the same 5'-derivative of enterolactone. After enzymatic hydrolysis and ether extraction the immunoassay is carried out using the VICTOR 1420 multilabel counter (Wallac Oy, Turku, Finland). No antiserum cross-reactivity with available lignans, isoflavonoids, or flavonoids could be detected. The intraassay and interassay coefficients of variation at different concentrations vary 4.6-6.0 and 5.5-9.9, respectively. The working range of the assay is 1.5-540 nmol/liter. We measured enterolactone in serum/plasma of 224 Finnish subjects: 98.8% of the subjects had values <100 nmol/liter, 38.0% had 20-39.9 nmol/liter, and 34.4% had <20 nmol/liter.     

Developments in UK service provision for people with epilepsy: the impact of the NHS Executive Letter 95/120

The author describes the operating course of the Occupational Medicine Operating Units (OMOU) in our region. (Lombardia) These Units, born as a second level support to the Basal Occupational Medicine Units, greatly enlarged, as time passed, the limits of their users together with the charge of preventive duties ordered to the employers by the recent laws regarding Occupational Hygiene. (DLgs 277/91-DLgs 626/94) The author also illustrates the variety of the diagnostic demands to the OMOU according to the enlargement of the legal protection of occupational diseases and to the numerous aspects of specific job fitness. He underlines the need of multiple specialistic skillfulnesses achievable by means of a complete integration of OMOU in to the hospital to which they belong. In conclusion the author illustrates the new tasks of the OMOU in the field of the therapy and rehabilitation.     

Intravascular ultrasound findings in stenting of unprotected left main coronary artery stenosis

We evaluated the role of intravascular ultrasound (IVUS) in 16 patients with unprotected left main coronary artery (LMCA) stenting compared with 80 patients with other (non-LMCA) native coronary artery stenting and found that (1) additional high-pressure or larger size balloon dilations were more frequently performed in LMCA stenting than in non-LMCA stenting (p <0.05) and (2) after IVUS-guided stent implantation, minimum lumen area was > or = 9 mm2 in 88% of patients who underwent LMCA stenting and in 19% of those who underwent non-LMCA stenting (p <0.001). IVUS guidance may be a more important adjunctive imaging modality in the stenting of unprotected LMCA stenoses than in stenting of non-LMCA stenoses.     

Extracorporeal membrane oxygenator support for cardiopulmonary failure. Experience in 28 cases

We have used extracorporeal membrane oxygenation (ECMO) for 28 patients (14 children and 14 adults) over a 5 year period. Nine patients improved on ECMO and 5 were long-term survivors. ECMO was used for pulmonary insufficiency in 24 patients. Initially, only moribund patients were treated, but recently the combination of open lung biopsy and pulmonary insufficiency index (PII) has been used to select patients. The best results have been obtained in newborn cases and the adult capillary leak syndromes; the major problem has been progression to fibrosis despite ECMO support. ECMO was used for cardiac failure in 4 patients. Children with postoperative cardiac failure did the best; profound shock was not reversed with venoarterial bypass. ECMO support is lifesaving in selected cases of pulmonary insufficiency. Initial trials in cardiac failure and the infant age group in this series suggest that ECMO will have an even greater role in those applications.