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Transoesophageal echocardiography (TEE) is a safe procedure with a low complication rate. We present a patient with severe coronary artery stenosis or disease who developed acute coronary ischemia of the anterior wall as a complication of TEE procedure. The possible mechanism can be stress during the procedure.
The case report describes a rare cause of acute myocardial infarction. 68-years old man with the cancer triplicity (follicular and papillar carcinoma of the thyroid gland, Grawitz tumor, bronchogenic carcinoma with generalization) was admitted to the intensive care unit for the sudden onset of chest pain, positivity of cardioselective enzymes and signs of cardiogenic shock. Echocardiographic examination proved diaphragmatic akinesis with low left ventricular ejection fraction about 30%. The acute coronary angiogram revealed unimportant atherosclerotic narrowing of the left coronary artery and a long significant stenosis in the proximal portion of the right coronary artery untypical for atherosclerotic lesion suspicious of extramural compression. A pathological vascularization to the extramyocardial region was documented during right coronary angiogram. The patient was treated conservatively and finally transferred to the pulmonary disease department, where he died of progression of the cancer disease two months later. Postmortem examination found spreading of the bronchogenic adenocarcinoma to the pericardium along the course of the right coronary artery, but neither direct infiltration of the vessel wall by the tumor nor atherosclerotic disease of the proximal portion of the right coronary artery were proved. These findings together with the coronary angiogram demonstrate a rare cause of the myocardial infarction due to the extramural compression by the malignant tumor.
PURPOSE: Case studies of four in vitro fertilization (IVF) cycles where embryo transport by commercial airline followed by biopsy and genetic analysis with subsequent culture to Day 5 and resulting ongoing pregnancy. METHOD: Retrospective clinical case study of 4 patients requiring preimplantation genetic diagnosis (PGD) testing. Normally fertilized embryos were transported in a battery-powered portable incubator by commercial airline following evaluation for fertilization under controlled conditions from the Center for Assisted Reproduction, Bedford, Texas to the Reproductive Genetic Institute, Chicago, Illinois. Following Day 3 embryo biopsy and genetic analysis, embryos were transported back to the Center for Assisted Reproduction for Day 5 embryo transfer. RESULTS: Ongoing clinical pregnancy resulted for all patients receiving embryo transfer. CONCLUSION: These results demonstrate the feasibility of embryo transport by air for centers that do not have the in-house capabilities to perform genetic analysis. With successful pregnancies obtained through extended culture to Day 5, embryos requiring genetic analysis can be successfully transported by air, tested, and returned to the initial facility for embryo transfer without time restriction.
Opportunities to examine patients with spastic angina pectoris are at present, due to the inaccessibility of ergonovine, very limited. The authors demonstrate on a small group of patients the application of echocardiographic hyperventilation test for assessment of the diagnosis of spastic angina pectoris.
We had reported previously that 2.5-5 microM sodium arsenite decreased the phenobarbital-mediated induction of CYP2H activity and protein but not CYP2H1 mRNA in chick-embryo hepatocyte cultures. Induction of a CYP1A activity and protein by 3-methylcholanthrene was also decreased by low arsenite concentrations; however, CYP1A mRNAs were not measured in those studies. We report here that low concentrations of arsenite decreased induction of activities and mRNAs of two chicken cytochromes P450, CYP1A (1A4 and 1A5), by 3-methylcholanthrene in chick-embryo hepatocyte cultures. Arsenite treatment did not affect the turnover of either mRNA, nor did it decrease the superinduction of each mRNA caused by treatment with cycloheximide in addition to 3-methylcholanthrene. Glutathione depletion enhanced the effect of arsenite to decrease induction of CYP1A4. These results indicate the induction of CYP1A4 and 1A5 is inhibited by sodium arsenite at the level of transcription, suggesting that the Ah receptor complex may be involved.
Problems which arise in conjunction with the use of assisted reproduction methods are no longer resolved only by the gynaecologist. The authors demonstrate on the case of a female patient the necessity of interdisciplinary collaboration in the diagnosis and therapy of developed ovarian hyperstimulation syndrome (OHSS)--the most serious complication of assisted reproduction.
We had previously reported that low concentrations of sodium arsenite (1-5 microM) decreased the induction of cytochrome P450 CYP1A and CYP2H in cultured chick embryo hepatocytes in parallel with increases in heme oxygenase. However, in those studies exogenous heme did not prevent the decrease in CYPs. In this study, we investigated the effect of arsenite on the synthesis and degradation of heme. Arsenite had no effect on induction of 5-aminolevulinic acid synthase mRNA or activity. Arsenite, at concentrations from 1 to 25 microM, had no effect on protoporphyrin synthesis from 5-aminolevulinic acid and did not increase the accumulation of other porphyrins, indicating that the enzymes in the pathway between 5-aminolevulinic acid synthase and ferrochelatase were unaffected by arsenite. Synthesis of heme from radioactive 5-aminolevulinic acid was slightly decreased (less than 20%) by 2.5 microM arsenite, a concentration that decreased induction of CYP1A and CYP2H by greater than 50%. Rates of biliverdin formation and degradation of exogenous heme were not different in cultures treated simultaneously with arsenite and heme or with heme alone. However, arsenite treatment increased biliverdin formation from heme synthesized from added 5-aminolevulinic acid by 60% and decreased the endogenous heme content of the cells by 30%. Our results suggest that although 2.5 microM arsenite induced heme oxygenase four- to sixfold, this had no effect on degradation of exogenous heme. Degradation of heme synthesized from 5-aminolevulinic acid was increased but this did not affect the regulatory heme pool.
A high-throughput screening strategy is described that involves the acquisition of two-dimensional 15N/1H correlation spectra in less than 10 min on 50 microM protein samples using cryogenic NMR probe technology. By screening at these concentrations, small organic molecules can be tested in mixtures of 100, which dramatically increases the throughput of the NMR-based assay. Using this strategy, libraries of more than 200 000 compounds can be tested in less than 1 month. There are many advantages of high-throughput NMR-based screening compared to conventional assays, such as the ability to identify high-affinity ligands for protein targets with no known function. This suggests that the method will be extremely useful for screening the large number of targets derived from genomics research.
OBJECTIVE: To evaluate the nonselective application of extended embryo culture on the outcome of IVF. DESIGN: Retrospective analysis. SETTING: Private practice assisted reproductive technology center. PATIENT(S): Seven hundred ninety nonselected patients undergoing IVF with controlled ovarian stimulation. INTERVENTION(S): For day 3 ET, multicell embryos were cultured in human tubal fluid medium and 12% synthetic serum substitute. For day 5 ET, embryos were cultured for 48 hours in S1 medium and then for 48 hours in S2 medium. MAIN OUTCOME MEASURE(S): Implantation rate (determined by total no. of visualized gestational sacs), ongoing pregnancy rate, and number of embryos available for ET. RESULT(S): Respective day 3 and day 5 implantation rates for patients aged <35 years (29.5% and 38.9%), patients aged 35-39 years (20.7% and 28.2%), and all patients combined (23.3% and 32.4%) were statistically significantly different. Significantly more embryos were transferred on day 3 than on day 5 for patients aged <35 years (2.9 vs. 2.4), patients aged 35-39 years (3.1 vs. 2.6), and all patients combined (3.0 vs. 2.5). The difference in ongoing pregnancy rates per retrieval was statistically significant for day 3 compared with day 5 transfers for all patients combined (35.9% vs. 43.8%). Cancellation rates for transfer after retrieval increased significantly for day 3 compared with day 5 transfer (2.9% vs 6.7%). CONCLUSION(S): These results demonstrate the feasibility of using extended embryo culture in a nonselective manner for couples undergoing IVF. Overall, extended embryo culture was associated with a significant increase in pregnancy rates and implantation rates and a significant decrease in the number of embryos transferred. The rate of multiple implantation among patients aged <35 years warrants consideration of single blastocyst transfers for this group.
UNLABELLED: In patients with atrioventricular dissociation associated with complete atrioventricular block or reverse synchronization and preservation of the sinus rhythm the atria are mechanically over-burdened by contraction in an inept stage of the cardiac cycle (against a closed atrioventricular valve). Prolonged overburdening leads to dilatation of the atria and a higher incidence of supraventricular arrhythmias incl. atrial fibrillation. The objective of the trial was to assess whether these changes are reversible. METHOD: In 26 patients where atrioventricular dyssynchronization as the only detectable reason of atrial dilatation was eliminated by implantation of sequential atrioventricular stimulation, the authors investigated by echocardiography the dimensions, volumes and ejection fractions of the atria and left ventricle at baseline (A), after 24 hours following implantation (B), after 8 weeks (C), after one year (D). RESULTS: Left atrium: during the first 24 hours diminution in the long axis occurred (AxB: -4.28, p = 0.023), the difference remained significant even after eight weeks (AxC: -6.1, p = 0.050). The ejection fraction was after eight weeks also significantly greater (BxC: +8.29, p = 0.039). Right atrium: within 24 hours the long axis was reduced (AxB: -4.70 p = 0.033), the difference was apparent also after 8 weeks (AxC: -5.60 p = 0.028). Within 8 weeks (AxC) the mean enddiastolic pressure diminished significantly (-11.01, p = 0.032) as well as the endsystolic volume (-9.01, p = 0.018, while the ejection fraction increased (+7.50, p = 0.031). The right ventricular volume during diastole increased between the 8th week and the check-up after one year (+6, -1, +17.77, p = 0.046). Left ventricle: the ejection fraction had a rising trend, after one year a significant difference was found as compared with the baseline value (AxD: +10.20%, p = 0.007) and as compared with the value assessed 8 weeks after implantation (CxD: +9.44%, p = 0.018). The change of the ejection fraction was inversely proportional to the value of the ejection fraction immediately after implantation (r -0.83, p < 0.01). CONCLUSION: The authors provided evidence of the reversibility of the morphological and functional atrial damage and the favourable effect of atrioventricular synchronization on left ventricular function.
In earlier studies, treatment with sodium arsenite was shown to decrease total hepatic CYP in rats. A concomitant increase in heme oxygenase, the rate-limiting step in heme degradation to biliverdin, was considered responsible for the decrease in CYP. Here we investigated the effect of sodium arsenite on induction of CYP2H, CYP1A, and heme oxygenase in primary cultures of chicken embryo hepatocytes. When added simultaneously with inducer, arsenite inhibited phenobarbital-mediated increases in CYP2H and 3-methylcholanthrene-mediated increases in CYP1A, as measured enzymatically and immunochemically. Near maximal decreases were observed in these forms of CYP at a concentration of 2.5 microM sodium arsenite. The concentration-dependent decreases in CYP2H and CYP1A by sodium arsenite were concomitant with increases in heme oxygenase. Sodium arsenite was not toxic at concentrations as high as 10 microM, as indicated by protein synthesis and the reduction of MTT by intact cells. Sodium arsenite had no effect on induction of CYP2H1 mRNA, suggesting that the decreases in this form of CYP occurred post-transcriptionally. Treatment of cells with tin mesoporphyrin (SnMeso), an inhibitor of heme oxygenase, resulted in inhibition of arsenite-induced heme oxygenase. However, SnMeso did not alter the effect of arsenite to prevent phenobarbital-mediated increases in CYP2H protein. SnMeso alone inhibited phenobarbital-mediated increases in CYP2H. Inclusion of 2 or 5 microM exogenous heme with arsenite did not prevent the arsenite-mediated decrease in CYP2H. Combined treatment with heme and phenobarbital induced heme oxygenase to the same extent as treatment with heme, arsenite, and phenobarbital. However, CYP2H activity was decreased only when the treatment included arsenite. These results suggest that elevated levels of heme oxygenase alone are not responsible for arsenite-mediated decreases in CYP2H.
Assisted reproduction techniques (ART) are modern medical methods which should help infertile couples to resolve their problems. With the introduction of ART new ethical and technical problems arise. The authors wish to demonstrate on the submitted two case-histories the need of interdisciplinary collaboration of the specialist in internal medicine and gynaecologist when dealing with a serious complication of ART--ovarian hyperstimulation syndrome (OHSS).
The authors describe their initial experience with examination of the heart by magnetic resonance (MR) and discuss its position in the diagnostic algorithm of cardiac examinations:. They made 31 MR examinations of the heart in 30 patients. Echocardiography preceded 29 examinations. MR proved to be particularly useful where echocardiography did not lead to a decisive conclusion and called for confirmation by another method, or where it could not be carried out or its result was not consistent with the patient's clinical condition or the results of other examinations. The quality of the MR image was influenced most by the possibility of ECG gating. The latter was not possible in 16 patients (51.6%). In three of these (18.8%) the images were of such poor quality that they did not provide adequate diagnostic information. Images suitable for evaluation were obtained in 28 examinations (90.3%)--in these patients the MR information was valuable for establishment of the diagnosis. Magnetic resonance is a new possible method in the non-invasive diagnosis of heart disease. In the majority of cases it follows after echocardiographic examination which remains due to its accessibility the basic non-invasive method for examination of the heart.
The effect of reducing the amount of cytoplasm available for early embryonic development was investigated in embryos produced by in vitro fertilization (IVF) and nuclear transplantation. In Experiment 1, approximately 1/2 or 1/20 of the cytoplasm was removed from bovine embryos at the pronuclear-stage of development. The percentage of embryos developing to the compact morula or blastocyst stage was significantly higher in non-manipulated controls (26%) than in embryos with 1/20 of the cytoplasm removed (16%), and those with 1/2 of the cytoplasm removed (10%; P < 0.05). There was also a significant difference in the average number of cells between blastocysts in which 1/20 of their cytoplasm was removed (67), those with 1/2 of their cytoplasm removed (55), and nonmanipulated controls (77; P < 0.05). In Experiment 2, nuclear transfer embryos were produced in which approximately 1/2 or 1/20 of the cytoplasm was removed during oocyte enucleation. The percentage of embryos developing to the blastocyst stage was 17% for both groups of nuclear transfer embryos compared to 44% for control embryos (P < 0.05). The mean number of cells in blastocysts produced by nuclear transfer in which 1/20 of the cytoplasm was removed during oocyte enucleation (61) was no different than that in control embryos (66), but significantly higher than the mean number of cells in blastocysts produced by nuclear transfer in which 1/2 of the cytoplasm was removed (42; P < 0.05). There was no indication that altering the amount of cytoplasm available for early embryonic development of IVF embryos affected the timing of differentiation events, including those of embryo compaction and blastocyst formation.
Injection of the circular plasmid FV1 (derived from type I bovine papilloma virus) into Xenopus eggs before the start of the first cell cycle dramatically increases the efficiency of plasmid replication once eggs are chemically activated. We call this the preloading effect and report kinetic and quantitative characterization of this phenomenon here. The timing and the amount of FV1 synthesis were measured by both BrdUTP density labelling and an optimized method of selective enzymatic digestion of replicated and unreplicated molecules using the three methyladenosine-sensitive isoschizomers, DpnI, MboI and Sau3a. DpnI in 100 mM NaCl proved particularly useful for distinguishing and quantitating unreplicated, once-replicated, and repeatedly replicated molecules accumulated over several cell cycles. Our results reveal that both the amount of DNA replicated and the timing of synthesis during the first S-phase correlate with the length of the preloading period. Longer preloading leads to larger amounts of DNA being replicated sooner. In fact, up to 30-50% of 1 ng injected plasmid can replicate in a semiconservative cell cycle-dependent manner during the first S-phase. But such high levels of synthesis during the first cell cycle appear to limit the egg's ability to rereplicate this material in subsequent cell cycles. The preloading effect does not depend on synthesis of either viral or egg proteins, but does appear to correlate with the extent of plasmid assembly into chromatin before the start of the cell cycle. We postulate that each plasmid molecule must achieve a critical degree of chromatin assembly before it can proceed along the replication pathway. These observations illuminate some of the difficulties inherent in building a vector for gene insertion into Xenopus embryos, but also suggest an experimental strategy toward this aim.
The authors administered to 10 patients with mild hypertension a single dose of 10 mg bisoprolol (Concor-Merck) during bioimpedance control of changes of the cardiac index and peripheral vascular resistance after an interval of 3 and 24 hours following administration of the drug. In all patients administration of the drug led to a statistically significant drop of the blood pressure. In patients with a high cardiac output (group A, n = 6) the decline of blood pressure was due to a blocked increment of the cardiac output and a slight block of the peripheral vascular resistance. In the group with a low cardiac output and high peripheral vascular resistance (group B, n = 3) the drop of the blood pressure was caused by peripheral vascular dilatation, the cardiac output was influenced minimally. Bisoprolol did not affect the left ventricular systolic function.
The authors administered to 10 patients with mild hypertension a single dose of 10 mg bisoprolol (CONCOR-Merck) during bioimpedance control of changes of the cardiac index and peripheral vascular resistance during an isometric load after an interval of 3 and 24 hours following administration of the drug. In all patients administration of the drug led during the third hour to a statistically significant drop of the blood pressure after a load. Twenty-four hours after administration the drop was no longer statistically significant. In patients with a high cardiac index (group A, n = 6) the decline of blood pressure was due to a blocked increment of the cardiac output and a slight block of the peripheral vascular resistance. In the group with a low cardiac index and high peripheral vascular resistance (group B, n = 3) the drop of the blood pressure was less marked than in group A and it was due only to the blocked increment of the cardiac output. The increment of the peripheral vascular resistance was not influenced by the preparation. Bisoprolol did not affect the left ventricular systolic function.