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PubMed2005

Temperature-driven decoupling of key phases of organic matter degradation in marine sediments.

The long-term burial of organic carbon in sediments results in the net accumulation of oxygen in the atmosphere, thereby mediating the redox state of the Earth's biosphere and atmosphere. Sediment microbial activity plays a major role in determining whether particulate organic carbon is recycled or buried. A diverse consortium of microorganisms that hydrolyze, ferment, and terminally oxidize organic compounds mediates anaerobic organic matter mineralization in anoxic sediments. Variable temperature regulation of the sequential processes, leading from the breakdown of complex particulate organic carbon to the production and subsequent consumption of labile, low-molecular weight, dissolved intermediates, could play a key role in controlling rates of overall organic carbon mineralization. We examined sediment organic carbon cycling in a sediment slurry and in flow through bioreactor experiments. The data show a variable temperature response of the microbial functional groups mediating organic matter mineralization in anoxic marine sediments, resulting in the temperature-driven decoupling of the production and consumption of organic intermediates. This temperature-driven decoupling leads to the accumulation of labile, low-molecular weight, dissolved organic carbon at low temperatures and low-molecular weight dissolved organic carbon limitation of terminal metabolism at higher temperatures.

Bacterial Physiological Phenomena↗
PubMed1979

Abnormal retino-geniculate and geniculo-cortical pathways in several genetically distinct color phases of the mink (Mustela vison).

Several genetically distinct color phases of mink, which all show an abnormal reduction of pigment in the retinal pigment epithelium and which also show abnormalities of the retinofugal pathways, have been studied. Autoradiographic methods have been used to demonstrate the retino-geniculate pathways, and retrograde degeneration or the retrograde transport of horseradish peroxidase has been used for the geniculo-cortical pathways. The retino-geniculate abnormality is mild in some of the color phases and extremely severe in others, but within any one color phase the variability is relatively low. Although the severity of the abnormality varies between color phases, a rather specific pattern of abnormal geniculate innervation is recognizable for mink in general and this is distinct from that found in Siamese cats. In the abnormal mink the size of geniculate lamina A1 is reduced and there is an abnormal crossed input going to the intermediate sectors of this reduced layer. Layer C1 also receives an abnormal crossed input, but this is more variable than that going to A1 and there appears to be little correspondence, retinotopically, between the normal inputs to layers A1 and C1. In some of the abnormal mink there are interruptions within the cytoarchitectionically definable layer A1, and opposite these gaps reduplications of layer A are commonly seen, as though there is an intrinsic geniculate mechanism for generating the characteristic multilaminar geniculate structure. However, there are also numerous examples of fusions between layers receiving afferents from the same eye, and these demonstrate that the development of geniculate lamination must also be under the influence of the retinal inputs. The geniculo-cortical pathway shows a normal topography in most of the mink. Abnormal geniculo-cortical projections, comparable to the "Boston" pattern of Siamese cats are extremely rare, and their occurrence could not be correlated with the severity of the retino-geniculate abnormality or with the laminar pattern in the lateral geniculate nucleus. We suggest that the development of one or the other pattern of geniculo-cortical projection may depend upon the relative timing of the two mechanisms that produce the geniculate lamination.

Animals↗
PubMed1998

Elevated pretreatment serum levels of soluble vascular cell adhesion molecule 1 and lactate dehydrogenase as predictors of survival in cutaneous metastatic malignant melanoma.

Very rapid progression of disease with a median survival of 6-9 months is a common feature of metastatic cutaneous malignant melanoma. Nevertheless, substantial variability of survival suggests that metastatic cutaneous malignant melanoma can be divided into several biological subgroups. Pretreatment serum levels of soluble adhesion molecules and various clinical parameters in cutaneous metastatic malignant melanoma were evaluated to determine their prognostic value. In this study pretreatment serum levels of soluble vascular cell adhesion molecule 1 (sVCAM-1), soluble intercellular cell adhesion molecule 1 (sICAM-1), soluble endothelial leukocyte adhesion molecule 1 (sE-selectin) and multiple clinical factors were assessed in relation to overall survival of 97 consecutive patients with metastatic cutaneous malignant melanoma seen at our institution between May 1990 and April 1996. For statistical analysis, both univariate and multivariate Cox proportional-hazards models were used. Elevated pretreatment serum levels of sVCAM-1 (P < 0.005) and of lactate dehydrogenase (P < 0.002) were rendered statistically independent and were significantly associated with unfavourable outcome. Patients were assigned to one of three risk categories (low, intermediate and high) according to a cumulative risk score defined as the function of the sum of these two variables. There were significant differences in overall survival (P < 0.0001) between low- (n = 53, 5-year survival probability of 23.3%), intermediate- (n = 29, 5-year survival probability of 9.9%) and high-risk (n = 15) patients. Elevated pretreatment serum levels of sVCAM-1 and of lactate dehydrogenase correlate with poor outcome in metastatic cutaneous malignant melanoma. These data support risk stratification for future therapeutic trials and identify factors that need to be validated in prospective studies and may potentially influence decision-making in palliative management of patients with disseminated cutaneous malignant melanoma.

Adult↗
PubMed1997

International scoring system for evaluating prognosis in myelodysplastic syndromes.

Despite multiple disparate prognostic risk analysis systems for evaluating clinical outcome for patients with myelodysplastic syndrome (MDS), imprecision persists with such analyses. To attempt to improve on these systems, an International MDS Risk Analysis Workshop combined cytogenetic, morphological, and clinical data from seven large previously reported risk-based studies that had generated prognostic systems. A global analysis was performed on these patients, and critical prognostic variables were re-evaluated to generate a consensus prognostic system, particularly using a more refined bone marrow (BM) cytogenetic classification. Univariate analysis indicated that the major variables having an impact on disease outcome for evolution to acute myeloid leukemia were cytogenetic abnormalities, percentage of BM myeloblasts, and number of cytopenias; for survival, in addition to the above, variables also included age and gender. Cytogenetic subgroups of outcome were as follows: "good" outcomes were normal, -Y alone, del(5q) alone, del(20q) alone; "poor" outcomes were complex (ie, > or = 3 abnormalities) or chromosome 7 anomalies; and "intermediate" outcomes were other abnormalities. Multivariate analysis combined these cytogenetic subgroups with percentage of BM blasts and number of cytopenias to generate a prognostic model. Weighting these variables by their statistical power separated patients into distinctive subgroups of risk for 25% of patients to undergo evolution to acute myeloid leukemia, with: low (31% of patients), 9.4 years; intermediate-1 (INT-1; 39%), 3.3 years; INT-2 (22%), 1.1 years; and high (8%), 0.2 year. These features also separated patients into similar distinctive risk groups for median survival: low, 5.7 years; INT-1, 3.5 years; INT-2, 1.2 years; and high, 0.4 year. Stratification for age further improved analysis of survival. Compared with prior risk-based classifications, this International Prognostic Scoring System provides an improved method for evaluating prognosis in MDS. This classification system should prove useful for more precise design and analysis of therapeutic trials in this disease.

Acute Disease↗
PubMed1980

The influence of environmental conditions and parasite-intermediate host-related factors on the transmission of Echinostoma liei.

Moderate freezing, desiccation, and pH levels of 5 and 6 killed the Echinostoma liei egg immediately or after only partial development, and increasing salinity levels above 3.79 0/00 and temperatures of 33 degrees C and 35 degrees C reduced the developmental potential. Temperatures of 6 degrees C and 8 degrees C and maintenance of eggs in mouse faeces arrested the development of the egg, and increasing temperatures decreaseds the time of development from 40 days at 18 degrees C to nine days at 35 degrees C. Maintenance of unembryonated eggs for 14 weeks in faeces at 12 degrees C and 22 degrees C and for 20 weeks in filtered pond water at 4 degrees C allowed a subsequent normal development, while embryonated eggs maintained at 4 degrees C only retained an unchanged hatchability for three weeks. A miracidium/snail density of 10:10 in 18 litres of water gave rise to an average level of parasitisation of 21%. Increasing miracidium/snail densities gave rise to increasing levels of parasitisation but to a level less than expected. The first intermediate host spectrum of E. liei was shown to be restricted to the genus Biomphalaria, but species variability in susceptibility within the genus and differences in survival of infected susceptible species was also demonstrated to exist. B. glabrata (Puerto Rico and St. Lucia), B. alexandrina (Qalyub), and B. pfeifferi (Malumfashi) were found to be susceptible, while B. camerunensis (Kinshasa) was almost refractory. Increasing size of B. glabrata (Puerto Rico) resulted in increasing daily cercarial production, but resistance to infection with increasing snail size was also demonstrated to exist. E. liei cercarial infectivity to the second intermediate host snail and the subsequent metacercarial infectivity to the mouse was found to be independent of the species of the first intermediate host and of the age of the infection in B. glabrata (Puerto Rico) for up to at least 6 1/2 weeks after the end of the prepatent period. No obvious peak in cercarial shedding fom the host snail occurred during the day. Five species of the genus Bulinus and Physa acuta (Egypt) were found to be highly susceptible as second intermediate host snails, whereas three species of the genus Biomphalaria, Planorbarius corneus (Rabat), Lymnaea natalensis (Egypt), and Helisoma duryi (Florida) all had a lower degree of susceptibility. On the other hand, E. liei metacercarial infectivity to the mouse was independent of the species and size of the second intermediate host snail. Also, the infectivity of metacercariae encysted on snail mucus, in snails harbouring patient redial infections, and in clean second intermediate host snails was comparable. Metacercarial infectivity remained unchanged for at least 12 and 18 weeks, respectively, when encysted in living B. glabrata (Puerto Rico) or when maintained in freshwater at 4 degrees C. Metacercariae in dead decaying B...

Animals↗
PubMed2003

[Thiopurine methyltransferase activity and myelosuppression in inflammatory bowel disease patients treated with azathioprine and 6-mercaptopurine].

BACKGROUND AND OBJECTIVE: We aimed at assessing whether there exists a relationship between thiopurine methyltransferase (TPMT) activity and the incidence of adverse events, especially myelotoxicity, in patients with inflammatory bowel disease treated with azathioprine (AZA) or 6-mercaptopurine (6-MP). PATIENTS AND METHOD: By means of a radiochemical method, we determined the TPMT activity in erythrocytes of patients with inflammatory bowel disease who had received previously or at the time of the study AZA or 6-MP (n = 97). A group of 37 patients who had never been treated with these drugs was included. We studied the relationship between several variables and TPMT values as well as their correlation with adverse events. RESULTS: Mean (SD) TPMT value was 20.8 (5) U/ml erythrocytes (from 7.8 to 32.7). There was no patient with low TPMT levels (< 5); 9% patients had intermediate levels (from 5 to 13.7 U/ml), while 91% displayed high levels (>= 13.8 U/ml). There were no differences when comparing TPMT values according to several variables such as age, gender, tobacco consumption, weight, type of inflammatory bowel disease, and treatment with 5-aminosalicylates, steroids or AZA/6-MP. Side effects were seen in 13 out of 97 (13%) patients administered AZA/6-MP. None patient with side effects exhibited low TPMT levels (< 5 U/ml), nor even intermediate levels (5-13.7 U/ml). There were no differences when comparing mean TPMT values in patients with side effects and in those without side effects. CONCLUSIONS: In this study, the usefulness of the determination of the TPMT activity to identify patients with inflammatory bowel disease at risk of myelotoxicity due to AZA or 6-MP has not been confirmed. Therefore, even when the TPMT enzymatic activity is normal, it is necessary to continue performing the periodic laboratory analysis.

Adult↗
PubMed1967

Free-operant compounding of variable-interval and low-rate discriminative stimuli.

Four rats were trained on a schedule containing stimuli associated with variable-interval 30-sec and differential-reinforcement-of-low-rate 20-sec schedules of reinforcement. Subsequently, a stimulus compounding test was administered that included individual presentations of two intensities of each stimulus plus compounds of these stimuli. In training, extremely high rates were emitted to the variable-interval stimulus, and very low rates to the differential-reinforcement-of-low-rate stimulus. Compounding the two training stimuli always produced an overall response rate intermediate between the rates controlled by the two stimuli separately presented. Essentially the same relationship held with different stimulus intensities. These results resolve the confounding of response and reinforcement variables present in previous conditioning studies reporting response averaging. They are discussed in terms of the incompatibility of the response chains associated with the individual stimuli compounded.

Animals↗
PubMed1990

Type VII collagen and 19-DEJ-1 antigen. Comparison of expression in inversa and generalized variants of recessive dystrophic epidermolysis bullosa.

The expression of type VII collagen and 19-DEJ-1 antigen was examined in 73 and 71 patients, respectively, with recessive dystrophic epidermolysis bullosa (RDEB), comprising gravis, mitis, inversa, and indeterminant subsets, to better determine the specificity and sensitivity of two monoclonal antibodies directed against these dermoepidermal junction-specific epitopes. Type VII collagen (LH 7:2 epitope) was usually absent (in 90%) in patients with the gravis variant of RDEB, whereas its expression was most often diminished (in 67%) in those with the mitis form of the disease. Only 2% and 5% of patients with gravis and mitis variants, respectively, had apparent normal amounts of type VII collagen within their skin. In contrast, six (86%) of seven patients with the inversa variant had normal expression of the antigen. Only 25% of all patients with RDEB lacked the 19-DEJ-1 antigen; of these, however, most had the gravis variant, although absence or diminution was also infrequently observed in those with the mitis and inversa forms. Intermediate findings were noted in patients classified as having indeterminant forms of RDEB. Some variability in antigen expression was also noted among affected siblings. We conclude that assessment of expression of the LH 7:2 epitope of type VII collagen may be diagnostically useful, although considerable overlap does exist between individual patients with gravis and mitis forms. 19-DEJ-1 expression is a far less sensitive probe in RDEB, although such data may prove useful in the assessment of newborns lacking the characteristic features of gravis disease. In addition, based on our experience with inversa RDEB, it would appear that altered expression of type VII collagen cannot be attributed to blister formation in this latter rare subset, since this antigen is usually strongly detected along the dermoepidermal junction, even in perilesional skin sites.

Antibodies, Monoclonal↗
PubMed1999

Fine-needle aspiration biopsy findings in marginal zone B cell lymphoma.

Marginal zone B cell lymphomas (MZBCLs) represent a category of non-Hodgkin's lymphoma which may arise in a wide variety of extranodal organs where they are termed low grade B cell lymphomas of mucosa-associated lymphoid tissue (MALT). MZBCLs may involve primarily lymph nodes and or spleen where they are designated monocytoid B cell lymphoma or splenic marginal zone lymphoma, respectively. Recognition of this category of lymphoma, in particular, extranodal MALT lymphoma, is clinically significant in determining optimal therapy. Although there have been recent case reports describing the cytologic findings in low grade MALT lymphoma in various extranodal organs, this category of lymphoma has not been widely recognized or discussed in the cytology literature. The cytologic findings in seven fine-needle aspirations and two bronchial washings of histologically confirmed marginal zone lymphoma (five extranodal MALT lymphomas and four nodal marginal zone lymphomas) are described. In all of the cases, the cytologic specimens showed a polymorphous proliferation comprising a predominant population of intermediate sized lymphoid cells with centrocyte-like or monocytoid features, transformed cells, and variable numbers of plasma cells. These findings, while highly suggestive of MALT lymphoma in extranodal proliferations, may be more difficult to distinguish from reactive conditions in lymph nodes.

Adolescent↗
PubMed1994

Emery-Dreifuss syndrome: genetic and clinical varieties.

Two familial and 2 sporadic cases of Emery-Dreifuss syndrome are reported. One family presented a rare autosomal dominant variant of Emery-Dreifuss muscular dystrophy, another with X-linked recessive inheritance showed unusual intrafamilial variability. One of sporadic cases closely resembled rigid spine syndrome, the other was clinically intermediate between Emery-Dreifuss muscular dystrophy and rigid spine syndrome, showing that they are not distinct disorders.

Adolescent↗
PubMed1993

MR imaging of eosinophilic granuloma: report of 11 cases.

The findings in 11 patients with histologically proven eosinophilic granuloma (EG) examined by magnetic resonance imaging (MRI) are described. In contrast with the variable appearance of EG on conventional radiography and computed tomography (CT), relatively constant features--intermediate to high signal intensity on T1-weighting, high signal intensity on T2-weighting, marked enhancement--were found on MRI. MRI was superior to other imaging methods in demonstrating bone marrow involvement and any accompanying soft tissue mass or inflammation. Intermediate to high signal intensity on T1-weighting and marked contrast enhancement could not be "explained" by histological findings. Prediction of the evolutionary phase of EG by MRI remains questionable because of the phase I (proliferative) histology of all 11 lesions.

Adolescent↗
PubMed1981

Ultrastructural studies on the nucleoli of the follicle cells in the lizards Acanthodactylus scutellatus hardyi and Eremias brevirostris.

The ultrastructure of the nuclei in the ovarian follicular cells has been examined in the lizards Acanthodactylus scutellatus hardyi, and Eremias brevirostris. During certain growth stages, the nuclei of the intermediate and the pyriform cells become large and conspicuous, and usually contain numerous morphologically variable nucleoli. The latter may be nucleolonemal, compact, ring-shaped, "filamentous", "fine-filamentous", "amorphous" or "course-granular" in type, and the number and type in each nucleus seems to be related to the developmental stage. The type of nucleolus may indicate different phases of activity in the nucleus and may also suggest an association with the production of different types of RNA.

Animals↗
PubMed1984

The bioavailability of oral intermediate-dose methotrexate. Effect of dose subdivision, formulation, and timing in the chemotherapy cycle.

The oral bioavailability of methotrexate is variable and may be dose-dependent. The absorption of 'interval' oral methotrexate, which is given between cycles of chemotherapy, is unknown. The bioavailability of oral methotrexate has been studied in eight patients, acting as their own controls, to assess the effect of subdivision of the dose, the formulation, and the timing of the methotrexate within the chemotherapy cycle. The mean bioavailability for all the oral methods of administration was 28.2% +/- 3.7% compared with the same dose given IV. Absorption was uninfluenced by subdivision of the dose, liquid or tablet formulation, or administration on day 1 or day 10 of the chemotherapy cycle.

Administration, Oral↗
PubMedDate not supplied

The use of stoichiometric relations for the description and analysis of microbial cultures.

A general method is described, which enables the derivation of predictive fermentation equations for any microbiological process. The method combines the well-known achievements of the elemental balance approach with microscopic, metabolic balances and biochemical restrictions, using the key intermediates concept. Special attention is paid to the distinction between independent and dependent flow variables of a system. The method is fully illustrated for the very simple example of heterotrophic growth on a single substrate without product formation. Other examples include growth on mixed substrates and the description of catabolic and anabolic product formation.

Adenosine Triphosphate↗
PubMed1987

Electrolocation in the presence of jamming signals: electroreceptor physiology.

Responses of ampullary and tuberous electroreceptor afferents were studied using moving electrolocation targets and electrical modulations of the animal's electric organ discharge as stimuli. The ability of the electroreceptors to encode these stimuli was measured with and without various forms of electrical jamming signals. The goal of this study was to measure the deterioration in electroreceptor responses due to the jamming signals, and to compare these results with the behavioral measures of electrolocation under the same conditions of jamming as described in the preceding report (Bastian 1987). 1. Three types of jamming stimuli were used to interfere with the tuberous electroreceptor afferents' ability to respond to the test stimuli mentioned above: Broad-band noise, high frequency stimuli consisting of a sinusoidal waveform having a frequency maintained at a chosen difference frequency (DF) from the EOD frequency of the fish being studied, and 5 or 50 Hz sinusoidal stimuli. 2. The tuberous receptor afferents' spontaneous frequency was sensitive to continuous presentation of all but the 5 Hz jamming signals. The 4 Hz DF signal caused the largest increase in spontaneous activity, the 50 Hz stimulus was intermediate in effectiveness, and the noise stimulus caused the smallest increase. Estimates of the variability of the ongoing receptor activity were also made, and both the 4 Hz DF and the 50 Hz stimuli reduced the coefficient of variation of the receptor activity, but noise had no significant effect on this parameter. Noise, 4 Hz DF, and 50 Hz jamming signals also reduced the tuberous receptors' responses to a 100 ms EOD amplitude modulation, and the 5 Hz stimulus was again ineffective. 3. Noise and 4 Hz DF jamming were also effective in reducing tuberous receptor afferents' responses to a moving metal electrolocation target. The 4 Hz DF stimulus was most effective in reducing the receptor's ability to encode information about the target. Receptor responses showed about a three-fold larger decrease per 10 dB increase in DF jamming amplitude as compared to similar sized increases in noise amplitude. Threshold target distances were also determined with and without noise and DF jamming, and again, the noise stimulus was less effective in reducing the distance at which electrolocation targets were just detectable. 4. Recordings from ampullary receptor afferents confirmed that the galvanic potentials produced by metal electrolocation targets stimulate these receptors while EOD distortions caused by such objects probably do not.(ABSTRACT TRUNCATED AT 400 WORDS)

Acoustic Stimulation↗
PubMed1987

Immunohistochemical evaluation of ras oncogene expression in pulmonary and pleural neoplasms.

We undertook an immunohistochemical analysis of human bronchopulmonary epithelial neoplasms and pleural mesotheliomas using a monoclonal antibody which recognizes ras oncogene products (p21ras). The monoclonal antibody, RAP-5, recognizes both unaltered and certain mutated p21ras. Formalin fixed and paraffin embedded tissue samples of 187 lung epithelial tumors and 27 pleural mesotheliomas were investigated; normal and bronchiectatic lungs were similarly studied. Normal lung and pleural tissue did not immunostain except for occasional type II pneumocytes. Reactive type II pneumocytes adjacent to carcinomas and bronchiectasis immunostained consistently. Twenty four/34 (71%) squamous carcinomas immunostained. Only 8/50 (16%) adenocarcinomas immunostained focally and weakly whereas 19/24 (79%) bronchioloalveolar carcinomas immunostained. Eleven/18 (61%) large cell carcinomas immunostained with variable intensity. Eleven/13 (85%) carcinoids, 6/7 (85%) well differentiated neuroendocrine carcinomas, and 18/21 (86%) intermediate cell neuroendocrine carcinomas immunostained while none of 20 small cell neuroendocrine carcinomas immunostained. Only a few mesotheliomas were immunostained focally. Two/14 (14%) epithelial type and 1/9 (11%) biphasic type mesotheliomas immunostained weakly; none of 4 spindle cell mesotheliomas immunostained. We conclude that while at least occasional cases of most types of pulmonary epithelial neoplasms express p21ras, the frequency and intensity of the expression are distinctly greater in certain tumor types such as squamous, bronchioloalveolar, and neuroendocrine neoplasm except for the small cell type. Contrary to these lung epithelial neoplasms, most mesotheliomas did not immunostain for p21ras. Whether the enhanced p21ras expression may point to a different mechanism of transformation or may merely reflect differentiation features remains undetermined.

Histocytochemistry↗
PubMed1993

Immunohistochemical localization of cytokeratin 17 in transitional cell carcinomas of the human urinary tract.

The expression of cytokeratin (CK) 17 was studied in 28 primary transitional cell carcinomas (TCCs) of the human urinary tract using CK 17-specific monoclonal antibody E3. While CK 17 was not detectable at all or only present in some areas of basal cells in normal--appearing urothelium, a certain subpopulation of cells of all G1 and G1/G2 TCCs examined (9 cases) stained positive for CK 17. These latter cells were either restricted to the basal compartment or located also in suprabasal layers exhibiting a decreasing intensity of immunoreactivity. CK 17 was seen in practically all cells in G2 and G2/G3 tumors (7 cases). In contrast, G3 TCCs and anaplastic carcinomas showed a highly variable CK 17 staining pattern ranging from completely negative to completely positive with several intermediate phenotypes. Our results indicate that CK 17 could be a useful marker for the progression of urinary tumors.

Biomarkers, Tumor↗
PubMed1986

Contribution of muscle relaxant to the haemodynamic course of high-dose fentanyl anaesthesia: a comparison of pancuronium, vecuronium and atracurium.

To define the role of muscle relaxants in haemodynamic responses to high-dose (75 micrograms X kg-1) fentanyl anaesthesia and to noxius stimuli associated with intubation and sternal spread during coronary artery bypass surgery, we compared haemodynamics between three groups of patients given either pancuronium (0.1 mg X kg-1, n = 11), vecuronium (0.086 mg X kg-1, n = 11) or atracurium (0.43 mg X kg-1, n = 12). Additional doses of the relaxants were given to maintain a 90 per cent neuromuscular block. Patients given pancuronium showed no increases in mean values of heart rate, arterial pressure or cardiac output during the induction of anaesthesia or after intubation, whereas a decrease in these variables was observed in the vecuronium group. The haemodynamics in the atracurium group were intermediate compared with the other two study groups. In spite of a decrease in coronary perfusion pressure, no patient given vecuronium developed myocardial ischaemia. An advantage of vecuronium over pancuronium and atracurium was an attenuation of the blood pressure response to sternotomy. Patients given atracurium had a small increase in pulmonary vascular resistance during sternotomy. Our patients continued their beta-adrenergic antagonist medication until the morning of the day of operation and they were pretreated with a small intravenous dose of diazepam (0.1 mg X kg-1) before induction of anaesthesia. These drugs may have prevented the deleterious haemodynamic effects observed by some investigators after the administration of pancuronium during high-dose fentanyl anaesthesia.

Adult↗