Water circulation in Ryugu asteroid affected the distribution of nucleosynthetic isotope anomalies in returned sample

Studies of material returned from Cb asteroid Ryugu have revealed considerable mineralogical and chemical heterogeneity, stemming primarily from brecciation and aqueous alteration. Isotopic anomalies could have also been affected by delivery of exogenous clasts and aqueous mobilization of soluble elements. Here, we show that isotopic anomalies for mildly soluble Cr are highly variable in Ryugu and CI chondrites, whereas those of Ti are relatively uniform. This variation in Cr isotope ratios is most likely due to physicochemical fractionation between 54Cr-rich presolar nanoparticles and Cr-bearing secondary minerals at the millimeter-scale in the bulk samples, likely due to extensive aqueous alteration in their parent bodies that occurred [Formula: see text] after Solar System birth. In contrast, Ti isotopes were marginally affected by this process. Our results show that isotopic heterogeneities in asteroids are not all nebular or accretionary in nature but can also reflect element redistribution by water.

A postpartum haemorrhage package with condom uterine balloon tamponade: a prospective multi-centre case series in Kenya, Sierra Leone, Senegal, and Nepal

OBJECTIVE

To evaluate the effectiveness and safety of an ultra-low-cost uterine balloon tamponade package (ESM-UBT™) for facility-based management of uncontrolled postpartum haemorrhage (PPH) in Kenya, Sierra Leone, Senegal, and Nepal.

DESIGN

Prospective multi-centre case series.

SETTING

Facilities in resource-scarce areas of Kenya, Sierra Leone, Nepal, and Senegal.

POPULATION

Women with uncontrolled postpartum haemorrhage in 307 facilities across the four countries.

METHODS

A standardised ESM-UBT package was implemented in 307 facilities over 29 months (1 September 2012 to 1 February 2015). Data were collected via a multi-pronged approach including data card completion, chart reviews, and provider interviews. Beginning in August 2014, women who had previously undergone UBT placement were sought and queried regarding potential complications associated with UBT use.

MAIN OUTCOME MEASURES

All-cause survival, survival from PPH, and post-UBT use complications (surgery, hospitalisation, antibiotics for pelvic infection) associated with UBT use.

RESULTS

201 UBTs were placed for uncontrolled vaginal haemorrhage refractory to all other interventions. In all, 38% (71/188) of women were either unconscious or confused at the time of UBT insertion. All-cause survival was 95% (190/201). However, 98% (160/163) of women survived uncontrolled PPH if delivery occurred at an ESM-UBT online facility. One (1/151) potential UBT-associated complication (postpartum endometritis) was identified and two improvised UBTs were placed in women with a ruptured uterus.

CONCLUSIONS

These pilot data suggest that the ESM-UBT package is a clinically promising and safe method to arrest uncontrolled postpartum haemorrhage and save women's lives. The UBT was successfully placed by all levels of facility-based providers. Future studies are needed to further evaluate the effectiveness of ESM-UBT in low-resource settings.

TWEETABLE ABSTRACT

Evidence for ESM-UBT as a clinically promising and safe method to arrest uncontrolled PPH and save women's lives.

Perinatal health care in a conflict-affected setting: evaluation of health-care services and newborn outcomes at a regional medical centre in Iraq

A field-based assessment was conducted to assess maternal and newborn health-care services, perinatal and newborn outcomes and associated risk factors at Bint Al-Huda Maternal and Newborn Teaching Hospital, a large referral hospital in southern Iraq. The multi-method approach used interviews, discussions, observation and review of perinatal and newborn outcome data. There is limited assessment of maternal vital signs, labour pattern, fetal response, and complications during pregnancy and labour. Perinatal and neonatal mortality rates are 27.4/1000 births and 30.9/1000 live births respectively. Associated neonatal mortality factors were gestational age < 37 weeks, male sex, birth weight < 2.5 kg, maternal age > 35 years, rural maternal residence and vaginal delivery. Improving birth outcomes in southern Iraq requires evidence-based clinical guidelines, additional supplies and equipment, quality improvement initiatives and in-service training.

Validation of genomic markers that predict distant recurrence risk via FISH assays in women with early stage breast carcinoma

10506

Background: Biomarkers offer the potential to better predict recurrence risk in early stage invasive breast cancer, especially if adaptable to common assays such as fluorescent in situ hybridization (FISH). We studied the ability of tumor copy numbers (CN) of 3 genes, BIRC5, CYP24, and PDCD6IP, to predict distant recurrence in women with breast cancer. Methods: We conducted a blinded, multi-site study of 350 women with lymph node negative, estrogen/progesterone receptor positive (ER/PR+), invasive ductal carcinomas with archived paraffin-embedded biopsy specimens available. Eligible women received local surgical and radiation treatment only (93) (LTO) or local treatment and tamoxifen therapy only (257), and had distant metastases or no evidence of distant recurrence with at least 5 years follow-up (FU). Tumors were subjected to FISH with DNA probes for the 3 genes to assess CN. A prognostic index (PI) was calculated for each patient based on the 3 genes’ CN. A predetermined threshold (3.0) was used to categorize PI's as low or high. Data were assessed by Fisher's exact analysis and by categorical and continuous Cox modeling. Results: The study included 350 women with Stage I (288) and II (62) disease. FU averaged 7.3 years. Distant recurrence occurred in 32 women (9.1%) overall and in 5.2% of women with Stage I disease. In a multivariate Cox analysis including continuous PI, age, tamoxifen treatment, grade, and tumor size, PI remained a significant predictor of recurrence for Stage I patients: OR=1.56, p=0.019, and Stage I/LTO patients: OR=6.02, p=0.00007. Using the PI as a categorical classifier, the high/low recurrence rates were significantly different: OR=2.24, p= 0.045. Similar results were seen in Stage I patients: OR=3.53, p=0.021 with recurrence rates of 3.5% and 11.5% in the low and high risk groups, respectively, and for the Stage I/LTO patients: OR=5.33, p=0.041. Conclusions: FISH analysis of 3 genes allows metastasis risk prediction in women with early stage ER/PR+ cancers. This may be particularly useful for Stage I cancers traditionally considered low risk. The markers are prognostic in that they predict metastasis in patients receiving only local therapy.

No significant financial relationships to disclose.

Chromatographic separation and multicollection-ICPMS analysis of iron. Investigating mass-dependent and -independent isotope effects

A procedure was developed that allows precise determination of Fe isotopic composition. Purification of Fe was achieved by ion chromatography on AG1-X8 strongly basic anion-exchange resin. No isotopic fractionation is associated with column chemistry within 0.02 per thousand /amu at 2sigma. The isotopic composition was measured with a Micromass IsoProbe multicollection inductively coupled plasma hexapole mass spectrometer. The Fe isotopic composition of the Orgueil CI1 carbonaceous chondrite, which best approximates the solar composition, is indistinguishable from that of IRMM-014 (-0.005 +/- 0.017 per thousand /amu). The IRMM-014 reference material is therefore used for normalization of the isotopic ratios. The protocol for analyzing mass-dependent variations is validated by measuring geostandards (IF-G, DTS-2, BCR-2, AGV-2) and heavily fractionated Fe left after vacuum evaporation of molten wüstite (FeO) and solar (MgO-Al(2)O(3)-SiO(2)-CaO-FeO in chondritic proportions) compositions. It is shown that the isotopic composition of Fe during evaporation of FeO follows a Rayleigh distillation with a fractionation factor alpha equal to (m(1)/m(2)()1/2), where m(1) and m(2) are the masses of the considered isotopes. This agrees with earlier measurements and theoretical expectations. The isotopic composition of Fe left after vacuum evaporation of solar composition also follows a Rayleigh distillation but with a fractionation factor (1.013 22 +/- 0.000 67 for the (56)Fe/(54)Fe ratio) that is lower than the square root of the masses (1.018 35). The protocol for analyzing mass-independent variations is validated by measuring terrestrial rocks that are not expected to show departure from mass-dependent fractionation. After internal normalization of the (57)Fe/(54)Fe ratio, the isotopic composition of Fe can be measured accurately with precisions of 0.2epsilon and 0.5epsilon at 2sigma for (56)Fe/(54)Fe and (58)Fe/(54)Fe ratios, respectively (epsilon refers to relative variations in parts per 10 000). For (58)Fe, this precision is an order of magnitude better than what had been achieved before. The method is applied to rocks that could potentially exhibit mass-independent effects, meteorites and Archaean terrestrial samples. The isotopic composition of a 3.8-Ga-old banded iron formation from Isua (IF-G, Greenland), and quartz-pyroxene rocks from Akilia and Innersuartuut (GR91-26 and SM/GR/171770, Greenland) are normal within uncertainties. Similarly, the Orgueil (CI1), Allende (CV3.2), Eagle Station (ESPAL), Brenham (MGPAL), and Old Woman (IIAB) meteorites do not show any mass-independent effect.

DH82 cells: a macrophage cell line for the replication and study of equine infectious anemia virus

In vivo, tissue macrophages have been implicated as an important cell for the replication of equine infectious anemia virus (EIAV). Laboratory investigations of EIAV/macrophage interactions, however, have been hampered by the laborious blood monocyte isolation procedures. In addition, adherent equine macrophage cultures generally have poor long-term viability and are resistant to transfection. This report describes an adherent canine macrophage-like cell line, DH82, that supports the replication of EIAV. This cell line was easily transfectable and supported EIAV Tat transactivation of the LTR. Electrophoretic mobility shift assays were carried out to determine which transcription factor binding sites within the LTR enhancer region were bound by DH82 nuclear extracts. It was found that five different motifs were occupied. The ets motifs that are bound by PU.1 in primary macrophage nuclear extracts specifically interacted with DH82 nuclear extracts. In addition, the PEA-2, Lvb and Oct motifs that are occupied by fibroblast nuclear extracts were also bound by DH82 nuclear extracts. Finally, the methylation-dependent binding protein (MDBP) site that is bound by all nuclear extracts investigated to date demonstrated specific interactions with DH82 nuclear extracts. The observation that both macrophage-specific and fibroblast-specific motifs were utilized by DH82 nuclear extracts suggested that both macrophage-adapted and fibroblast-adapted EIAV could replicate in DH82 cells. Indeed, infectivity studies demonstrated that strains of virus that exclusively replicate in macrophages can replicate in DH82 cells and fibroblast-adapted strains of virus can also replicate in these cells. Finally, these cells could be transfected readily with the EIAV molecular clone, pSPeiav19-2, and virus spread was detected within the culture. In conclusion, this study has identified a useful cell line that should facilitate the study of EIAV expression and replication.

Successful community-based laboratory services program for long-term care facilities, Part 2

Hagerstown Medical Laboratory, Inc., located in Hagerstown, Maryland, has an outreach program that currently provides laboratory services to 52 long-term care facilities. Part 1 of this series, published in the May/June 2001 issue of Clinical Leadership & Management Review, discussed general organization, staffing, and safety issues for their Nursing Home Program. Part 2 relates their experience with contracts, fees, and reimbursement.

Successful community-based laboratory services program for long-term care facilities, Part 1

Hagerstown Medical Laboratory, Inc. (HML) is a regional reference laboratory in Hagerstown, Maryland, that provides laboratory services to more than 50 long-term care facilities (LTCFs, or nursing homes) in Western Maryland and West Virginia. HML also operates the rapid response laboratory at Washington County Hospital and performs house calls for homebound or bedridden patients through its Nursing Home Program (NHP). This article relates HML's successful experience with an outreach program that provides laboratory services to LTCFs.

Cell specificity of the transcription-factor repertoire used by a lentivirus: motifs important for expression of equine infectious anemia virus in nonmonocytic cells

The equine infectious anemia virus (EIAV) long-terminal repeat (LTR) has been identified as highly variable, both in infected horses and in cell culture. This nucleotide hypervariation is localized to the LTR enhancer region. The EIAV LTR has been implicated in controlling both the cell tropism and virulence of the virus and it is postulated that the enhancer-region hypervariation may be responsible for the LTR effects. Our previous studies have demonstrated that the presence of DNA motifs bound by the ets transcription-factor family member PU.1 are critically important for EIAV expression in equine macrophages. Here we identify and characterize the EIAV LTR enhancer motifs PEA-2, Lvb, Oct, and CRE, that bind to fibroblast nuclear extracts. Three of these four motifs, PEA-2, Oct, and CRE, were determined to be important for expression of the LTR in a fibroblast cell line that supports productive infection of EIAV. These motifs that are important for expression of the LTR in fibroblasts were found to be interdigitated between the PU.1 sites. We hypothesize that the combination of motif interdigitation and cell-specific usage of these motifs may be responsible for the observed EIAV LTR enhancer-region hypervariation.

Pharmacology and biological efficacy of a recombinant, humanized, single-chain antibody C5 complement inhibitor in patients undergoing coronary artery bypass graft surgery with cardiopulmonary bypass

BACKGROUND

Cardiopulmonary bypass (CPB) induces a systemic inflammatory response that causes substantial clinical morbidity. Activation of complement during CPB contributes significantly to this inflammatory process. We examined the capability of a novel therapeutic complement inhibitor to prevent pathological complement activation and tissue injury in patients undergoing CPB.

METHODS AND RESULTS

A humanized, recombinant, single-chain antibody specific for human C5, h5G1.1-scFv, was intravenously administered in 1 of 4 doses ranging from 0.2 to 2.0 mg/kg before CPB. h5G1.1-scFv was found to be safe and well tolerated. Pharmacokinetic analysis revealed a sustained half-life from 7.0 to 14.5 hours. Pharmacodynamic analysis demonstrated significant dose-dependent inhibition of complement hemolytic activity for up to 14 hours at 2 mg/kg. The generation of proinflammatory complement byproducts (sC5b-9) was effectively inhibited in a dose-dependent fashion. Leukocyte activation, as measured by surface expression of CD11b, was reduced (P<0.05) in patients who received 1 and 2 mg/kg. There was a 40% reduction in myocardial injury (creatine kinase-MB release, P=0.05) in patients who received 2 mg/kg. Sequential Mini-Mental State Examinations (MMSE) demonstrated an 80% reduction in new cognitive deficits (P<0.05) in patients treated with 2 mg/kg. Finally, there was a 1-U reduction in postoperative blood loss (P<0. 05) in patients who received 1 or 2 mg/kg.

CONCLUSIONS

A single-chain antibody specific for human C5 is a safe and effective inhibitor of pathological complement activation in patients undergoing CPB. In addition to significantly reducing sC5b-9 formation and leukocyte CD11b expression, C5 inhibition significantly attenuates postoperative myocardial injury, cognitive deficits, and blood loss. These data suggest that C5 inhibition may represent a novel therapeutic strategy for preventing complement-mediated inflammation and tissue injury.

Correlation of polyamine and growth responses to N1,N11-diethylnorspermine in primary fetal fibroblasts derived from transgenic mice overexpressing spermidine/spermine N1-acetyltransferase

A recently generated transgenic mouse line having activated polyamine catabolism due to systemic overexpression of spermidine/spermine N1-acetyltransferase (SSAT) was used to isolate primary fetal fibroblasts as a means to further elucidate the cellular consequences of activated polyamine catabolism. Basal levels of SSAT activity and steady-state mRNA in the transgenic fibroblasts were about approximately 20- and approximately 40-fold higher than in non-transgenic fibroblasts. Consistent with activated polyamine catabolism, there was an overaccumulation of putrescine and N1-acetylspermidine and a decrease in spermidine and spermine pools. Treatment with the polyamine analogue N1,N11-diethylnorspermine (DENSPM) increased SSAT activity in the transgenic fibroblasts approximately 380-fold, whereas mRNA increased only approximately 3-fold, indicating post-mRNA regulation. SSAT activity in the nontransgenic fibroblasts increased approximately 200-fold. By Western blot, enzyme protein was found to increase approximately 46 times higher in the treated transgenic fibroblasts than non-transgenic fibroblasts: a value comparable to 36-fold differential in enzyme activity. With DENSPM treatment, spermidine pools were more rapidly depleted in the transgenic fibroblasts than in nontransgenic fibroblasts. Similarly, transgenic fibroblasts were much more sensitive to DENSPM-induced growth inhibition. This was not diminished by co-treatment with an inhibitor of polyamine oxidase, suggesting that growth inhibition was due to polyamine depletion per se as opposed to oxidative stress. Since the two fibroblasts were genetically identical except for the transgene, the various metabolic and growth response differences are directly attributable to overexpression of SSAT.

Intentional and unintentional injury in the State of Nevada: 1989-1992

INTRODUCTION

Data from a large population-based trauma registry were used to assess risk factors and outcomes associated with injuries that were either caused unintentionally, were self-inflicted, or resulted from an assault.

DESIGN

A retrospective analysis was conducted of all cases of serious trauma (N = 19,505) occurring in the State of Nevada during the 4-year period from January 1, 1989, through December 31, 1992. The outcome measures of interest were Injury Severity Score, hospitalization, and mortality.

RESULTS

Of all patients with unintentional injuries, 9.9% died compared with 44.8% of those whose injuries were intentionally caused. Nearly half (49.0%) of all deaths occurred in persons who were intentionally injured. Of the intentional injuries, 70% were from assaults. Self-inflicted injuries accounted for 5.2% of all injuries but 28.2% of the deaths in the registry. Firearms were most often used in both assaults (38.8%) and self-inflicted injuries (87.4%). Logistic regressions showed that, compared with unintentional injuries, assaults were more likely to occur in urban counties, among males, African Americans, and young adults. Also, compared with unintentional injuries, self-inflicted injuries were more likely to occur in urban counties, among Caucasian, and the 65+ age group.

CONCLUSION

Although the overwhelming number of injuries in the registry were unintentionally caused, deaths from intentionally caused injuries accounted for almost half of all deaths. The data from Nevada's registry provided the ability to identify who is at risk for trauma-related injury and death. Prevention programs should be designed to target these populations. As prevention programs are implemented, trauma registries such as Nevada's will provide a sound source of data for assessing long-term trends in injury patterns.

Ovulation induction in clomiphene-resistant anovulatory women with normal dehydroepiandrosterone sulfate levels: beneficial effects of the addition of dexamethasone during the follicular phase

OBJECTIVE

To evaluate the effect on ovulation of a 10-day course of dexamethasone (DEX) initiated concurrently with a 5-day course of clomiphene citrate (CC) in CC-resistant patients with normal DHEAS levels.

DESIGN

Retrospective review.

SETTINGS

Patients from the clinical practice of the authors at the Medical College of Georgia, Augusta, Georgia.

PATIENTS

Thirteen oligomenorrheic women with normal DHEAS levels who failed to ovulate on a graduated regimen of CC up to a dose of 150 mg for 5 days.

INTERVENTIONS

Ten-day course of DEX initiated concurrently with a 5-day course of CC; ovulation and pregnancy outcomes recorded.

MAIN OUTCOME MEASURE

Pregnancy.

RESULTS

Eleven of 13 women had evidence of ovulation. Five clinical pregnancies were achieved.

CONCLUSION

These initial data support improvements in follicular development with an overlapping follicular phase regimen of CC and DEX in patients with normal DHEAS levels and a previous poor response.

Nitroprusside inhibition of platelet function is transient and reversible by catecholamine priming

BACKGROUND

The time course and reversibility of sodium nitroprusside's in vivo inhibition of platelet function are unclear.

METHODS

Platelet aggregation and P-selectin expression as measures of platelet dense and alpha-granule release, respectively, were examined before and after administration of sodium nitroprusside (18 mg) to human volunteers and in in vitro studies. Hypotension occurring with sodium nitroprusside administration was treated with intravenous crystalloid and/or phenylephrine.

RESULTS

Compared with preinfusion studies, platelet aggregation to epinephrine was significantly inhibited immediately and 4 min after discontinuation of the sodium nitroprusside infusion but returned to baseline at 8 and 12 min after discontinuing sodium nitroprusside. However, both dense and alpha-granule release to adenosine diphosphate after in vivo sodium nitroprusside were never significantly inhibited even at the time when sodium nitroprusside infusion was maximal. In contrast to our in vivo findings, in vitro incubation of platelet-rich plasma with sodium nitroprusside resulted in significant inhibition of dense and alpha-granule release to adenosine diphosphate. These in vitro inhibitory effects of sodium nitroprusside were reversed by pretreatment with epinephrine but not phenylephrine.

CONCLUSIONS

In normal volunteers, sodium nitroprusside inhibits platelet aggregation to epinephrine but not adenosine diphosphate; inhibition was reversed within 8-12 min after discontinuing sodium nitroprusside. Sodium nitroprusside in vitro inhibition of platelet function to adenosine diphosphate was reversed by epinephrine pretreatment. Because of the rapid reversibility of its antiplatelet effect, sodium nitroprusside may be clinically useful even when there is the potential for impaired coagulation.

Treatment of postoperative hypertension after coronary artery bypass surgery. Double-blind comparison of intravenous isradipine and sodium nitroprusside

BACKGROUND

Hypertension commonly occurs after cardiac surgery and requires therapy to prevent the potentially deleterious effects.

METHODS AND RESULTS

After coronary artery bypass graft surgery (CABG), 177 patients with elevated blood pressure > or = 90 mm Hg during the initial 6-hour postsurgical period were selected for this random blinded, parallel study to receive intravenous infusions of either isradipine (n = 90) or sodium nitroprusside (n = 87). Isradipine produced a statistically significant decrease in mean arterial pressure (MAP, delta-23 mmHg) during a 90-minute treatment period. Target MAP (< or = 85 mmHg or a decrease of 10 mmHg, if baseline MAP was between 90 and 95 mmHg) was achieved in 94% of patients 30 minutes after initiation of isradipine infusion (total mean dose, 411 micrograms); target MAP was achieved in 75% of nitroprusside-treated patients (total mean dose, 1708 micrograms). The mean time to control MAP was 18 minutes for isradipine compared with 24 minutes for nitroprusside. Global smoothness in MAP control was graded on a scale of 0 (not controlled) to 5 (excellent). Approximately 76% of isradipine-treated patients received a rating of > or = 3 (mean score, 3.5); 40% of the sodium nitroprusside-treated patients achieved a score of > or = 3 (mean score, 2.0). Both isradipine and nitroprusside produced statistically significant reductions in systolic and diastolic blood pressures, a decrease in systemic vascular resistance, and increases in heart rate, cardiac index, and stroke volume index. Isradipine produced no significant decreases in pulmonary artery occlusion wedge pressure compared with nitroprusside.

CONCLUSIONS

Intravenous isradipine was effective and well tolerated in patients with hypertension after CABG and offers an additional therapeutic option to treat patients after cardiac surgery.

Childhood psychological trauma and chronic refractory low-back pain

OBJECTIVE

To examine the correlation between childhood psychological trauma(s) and refractory back pain in patients with and patients without prior spine surgery.

DESIGN

Retrospective chart review survey of 101 consecutive patients who had undergone multidisciplinary evaluation for refractory back pain.

SETTING

Private practice, tertiary care spine center.

MAIN OUTCOME MEASURES

Each psychological risk factor (physical abuse, sexual abuse, emotional neglect or abuse, abandonment, and chemically dependent caregiver) was rated as present or absent. Spinal pathology was graded as significant or not significant.

RESULTS

There were 56 patients with failed back surgery syndrome, 28 men and 28 women, with a mean age of 43 and mean pain duration of 45 months. There were 45 patients with no prior surgery, 26 men and 19 women, with a mean age of 43 and mean pain duration of 33 months. In the failed back surgery syndrome group, 27 (48%) had three or more risks and 39 (70%) had two or more. When the 12 patients with significant pathology are not considered, 24 of the remaining 44 (55%) patients had three or more risks. In the group with no prior surgery, 26 (58%) had three or more risks and 38 (84%) had two or more. When the five patients with significant pathology are not considered, 24 (60%) had three or more risks.

CONCLUSIONS

Multiple childhood psychological traumas may predispose a person to chronic low back pain. In patients in this setting with refractory low back pain with or without prior lumbar spine surgery, three or more childhood psychological risk factors are prevalent, especially in patients with minimal structural pathology.

Transesophageal two-dimensional echocardiographic analysis of right ventricular systolic performance indices during coronary artery bypass grafting

Sixteen patients (aged 59 +/- 14 years) undergoing coronary artery bypass surgery were evaluated to delineate the intraoperative course of transesophageal echocardiographic right ventricular (RV) systolic performance indices. Pre-induction data included thermodilution RV ejection fraction (RVEFTD), 0.43 +/- 0.13, RV end-diastolic volume index (EDVI), 110 +/- 33 mL/m2, cardiac index (CI), 3.4 +/- 1.0 L/min/m2, RV end-diastolic pressure (EDP), 7.1 +/- 4.2 mmHg, and mean pulmonary artery pressure (PAP), 21 +/- 6 mmHg. Eleven patients had significant right coronary artery (RCA) disease (> 70% occlusion). Five patients arrived with an ongoing nitroglycerin infusion (1 to 3 micrograms/kg/min), which was maintained intraoperatively. Echocardiographic measurements included longitudinal-axis (LA) and short-axis (SA) planimetered area excursion fractions (2DLA and 2DSA, respectively) and LA maximal major and minor axis shortening fractions (max majorLA and max minorLA, respectively). Hemodynamic measurements included RVEFTD, EDVI, CI, EDP, and PAP. Measurements were determined following induction/endotracheal intubation, following sternotomy/pericardiotomy, and after cardiopulmonary bypass (CPB) with the chest open. All patients were maintained on vasodilator therapy post-CPB (nitroglycerin, 1 to 3 micrograms/kg/min [N = 16] and nitroprusside, 0.5 to 4.5 microgram/kg/min [N = 4]) post-CPB. Two patients received inotropic support (epinephrine, 0.2 to 0.3 microgram/kg/min). CPB was associated with significant decreases in max major axisLA and 2DLA (P < 0.05) as compared to measurements determined prior to CPB. Maximum major axisLA values pre-CPB were 0.35 +/- 0.06 and 0.33 +/- 0.08 versus post-CPB values of 0.24 +/- 0.08.(ABSTRACT TRUNCATED AT 250 WORDS)

Thermodilution right ventricular ejection fraction measurement reproducibility--a study in patients undergoing coronary artery bypass graft surgery

OBJECTIVE

To assess the effects of heart rate, right ventricular systolic performance (ejection fraction), chamber dimensions, and flow rate (cardiac index) on the reproducibility of algorithm-derived triplicate thermodilution right ventricular ejection fraction measurements.

DESIGN

Prospective study; combined hemodynamic and echocardiographic clinical evaluation.

SETTING

Operating room in a university hospital.

PATIENTS

Twenty-one coronary artery bypass graft patients.

MEASUREMENTS AND MAIN RESULTS

The right atrial delivery site was positioned by analysis of transduced pressure waveform and echocardiographic imaging of tracer agitated saline cavitations. Measurement reproducibility was quantified by determining the variation (standard deviation) within 101 triplicate thermodilution measurement sets. There was no significant relationship between measurement reproducibility and estimates of right atrial area (21.6 +/- 6.9 cm2), diameter (5.1 +/- 0.8 cm) and supero-inferior length (5.1 +/- 0.9 cm) and right ventricular maximal minor axis diastolic diameter (4.21 +/- 1.05 cm). Reproducibility was also unrelated to right ventricular end-diastolic volume index (97.9 +/- 32.7 mL/m2) and cardiac index (2.9 +/- 0.9 L/min/m2). Measurement reproducibility was directly related to mean right ventricular ejection fraction (0.39 +/- 0.14) and inversely related to heart rate (80.8 +/- 18.6 beats/min) (p < .01 and < .001, respectively).

CONCLUSIONS

Thermodilution-derived right ventricular ejection fraction measurement reproducibility was unrelated to estimates of right atrial and ventricular dimensions and cardiac index. Measurement reproducibility was a direct function of right ventricular systolic performance and an indirect function of heart rate. Measurement should be interpreted with these constraints in mind.

The effect of calcium on pulmonary vascular resistance and right ventricular function

Calcium chloride is frequently administered to patients immediately after separation from cardiopulmonary bypass to improve the contractile state of the myocardium. Animal studies suggest that calcium chloride may produce increases in pulmonary vascular resistance, which can precipitate right ventricular failure. In an attempt to determine the effect of calcium chloride administration after cardiopulmonary bypass on right ventricular function, this study was designed to evaluate patients with normal and elevated pulmonary vascular resistance. Fifty patients scheduled for elective cardiac surgery were prospectively studied for changes in ionized calcium levels before and after bypass. The impact of calcium administration on right ventricular function was assessed by a pulmonary artery catheter modified for the measurement of right ventricular ejection fraction. In all patients the level of ionized calcium decreased during bypass from a mean of 4.91 to 4.29 mg.dl-1. However, the infusion of calcium chloride (10 mg.kg-1) after bypass resulted in increasing the ionized calcium levels to prebypass levels. Administration of calcium chloride after bypass to patients with normal right ventricular function resulted in a transient increase in both cardiac output and right ventricular ejection fraction without any change in pulmonary vascular resistance. Eight patients with both elevated pulmonary vascular resistance and depressed right ventricular function were evaluated to determine the effect of calcium chloride after bypass on pulmonary vascular resistance and right ventricular ejection fraction. Administration of calcium chloride (10 mg.dl-1) to these patients did not result in any significant increase in pulmonary vascular resistance or depression of right ventricular performance. More important, in these patients, right ventricular ejection fraction and cardiac output were significantly increased after calcium chloride administration. In summary, the results of this study fail to demonstrate any increase in pulmonary vascular resistance or deterioration of right ventricular function with the administration of calcium chloride (10 mg.kg-1) after bypass in patients with elevated pulmonary vascular resistance.

Childhood psychological trauma correlates with unsuccessful lumbar spine surgery

In a retrospective study of 86 patients who underwent lumbar spine surgery, patients who had three or more of a possible five serious childhood psychological traumas (risk factors) had an 85% likelihood of an unsuccessful surgical outcome. Conversely, in patients with a poor surgical outcome, the incidence of these traumas was 75%. In the group of 19 patients with no risk factors, there was only a 5% incidence of failure. This study shows that a highly significant correlation exists between unsuccessful lumbar spine surgery and a history of childhood traumas. Although recognition of predictors for unsuccessful outcome can be useful in avoiding surgery in patients whose indications for surgery are borderline, the greater challenge is to help the patient who, despite being at high psychological risk for negative outcome, has severe spinal pathology that will likely require surgery. In such cases, psychiatric treatment is critical. In the group of 19 patients with no risk factors, single-level laminectomies and discectomies were performed on 6 patients. The other 13 cases were complex, involving a combination of repeat surgeries (n = 4) fusions (n = 3), and/or multilevel laminectomies and discectomies (n = 11).

Complications occurring in the postanesthesia care unit: a survey

To identify and quantitate complications occurring in the postanesthesia care unit (PACU), a prospective study evaluated 18,473 consecutive patients entering a PACU at a university teaching hospital. Using a standardized collection form, the incidence of intraoperative and PACU complications was determined. The combined PACU and intraoperative complication rate was 26.7%. Data showed a PACU complication rate of 23.7%, with an overall intraoperative complication rate of 5.1%. Nausea and vomiting (9.8%), the need for upper airway support (6.9%), and hypotension requiring treatment (2.7%) were the most frequently encountered PACU complications. Patients in whom PACU complications developed were analyzed by ASA physical status. Of all patients experiencing nausea and vomiting (n = 1571), the highest percentage were ASA physical status II patients (n = 831). Likewise, in the group of 1450 patients who demonstrated a need for upper airway support, 792 were ASA physical status II. In patients experiencing a major cardiovascular complication, for example, variables associated with a greater risk of developing any PACU complications were ASA physical status (status II), duration of anesthesia (2-4 h), anesthetic technique, emergency procedures, and certain types of surgical procedures (orthopedic or abdominal). For patients admitted with a temperature of less than 35 degrees C the duration of the PACU stay was 152 +/- 46 min compared with 116 +/- 65 min for patients with a temperature greater than or equal to 36 degrees C (P less than 0.01). In conclusion, events occurring during the PACU period continue to be a source of patient morbidity.

Cardiopulmonary bypass induces leukocyte-platelet adhesion

Cardiopulmonary bypass (CPB) has been demonstrated to activate platelets, producing an increased number of circulating platelets that have undergone alpha-granule release and express granule membrane protein-140 (GMP-140) on their surface. In vitro, GMP-140 mediates activated platelet adhesion to neutrophils (PMN) and monocytes, causing the formation of leukocyte-platelet conjugates. Using a newly developed assay that measures the percentage of circulating leukocyte-platelet conjugates in whole blood, we studied 17 patients undergoing CPB and have determined that (1) monocyte-platelet conjugates increased significantly during CPB, from 18% +/- 1.5% to 44% +/- 4.5% (mean +/- SEM) by the end of CPB, while PMN-platelet conjugates increased only slightly and lymphocyte-platelet conjugates decreased; (2) the time course of the increase in monocyte- and PMN-platelet conjugates paralleled that of the increase in circulating activated platelets, as determined by the presence of surface GMP-140; and (3) monocyte activation, as assessed by increased surface expression of CD11b, showed a gradual increase similar to the increase in monocyte-platelet conjugates, while PMN surface CD11b peaked immediately after the start of CPB. We conclude that CPB, through increased platelet GMP-140 expression, causes formation of monocyte-platelet, and to a lesser extent, PMN-platelet conjugates. The activation of monocytes and PMN on CPB, as evidenced by CD11b expression, occurs with differing time courses.

Right ventricular function and failure: a review

The importance of right ventricular (RV) function in maintaining global cardiac performance is the focus of this discussion. The physiological determinants of normal right ventricular function will be discussed, with particular emphasis on the afterload and contractility characteristics of the right ventricle. Numerous clinical conditions have been shown to affect RV performance. These conditions include positive-pressure ventilation, ischemia, pulmonary hypertension, and cardiac surgery. Present methods for the perioperative evaluation of RV function include angiography, radionuclide techniques, thermodilution techniques, echocardiography, and magnetic resonance imaging. Traditional modalities for the treatment of RV dysfunction consist of pharmacological interventions (i.e., vasodilators and inotropes) and/or mechanical assist devices. Newer pharmacological strategies for the treatment of RV failure and associated pulmonary hypertension include the phosphodiesterase fraction III inhibitors and the prostaglandins, specifically PGE1. In summary, the accurate evaluation of perioperative RV performance combined with new treatment options will ensure maximal preservation of RV performance.

A Veterans Administration Cooperative Study of biphasic calcium phosphate ceramic in periodontal osseous defects

One hundred thirty-seven V.A. patients were randomized to one of three treatment groups to evaluate the efficacy of biphasic calcium phosphate (BCP) ceramic in the treatment of periodontal osseous defects. This material was tested against both autogenous bone implant and open flap curettage procedures. Baseline probing attachment level, Navy plaque index, and gingival index were recorded for all patients. These parameters were monitored for 3 years. At the end of this period, 101 patients had completed the study. Although the plaque and gingival indices steadily increased with time, there were no statistically significant differences among the treatment groups. Patients in the ceramic group had a gain in attachment level of 1.0 mm; those in the curettage group, 0.9 mm; and 0.4 mm for those in the bone implant group. Although the BCP patients had a greater gain, the difference was not statistically significant. In this veteran population, not only did BCP patients fail to outperform those in the control groups, all three treatment groups were similarly ineffective.

Immunochemical and molecular biological studies on human placental cigarette smoke-inducible cytochrome P-450-dependent monooxygenase activities

The induction of specific forms of cytochrome P-450 and P-450-associated xenobiotic-metabolizing monooxygenase activities by maternal cigarette smoking was characterized in human placenta employing polyclonal and monoclonal antibodies and recombinant DNA probes. The anti-BNF-B2 (prepared against rat liver P-450 induced by beta-naphthoflavone) inhibited about 60 per cent of aryl hydrocarbon hydroxylase (AHH) and 7-ethoxyresorufin O-deethylase activities (ERDE) in placental tissues from smoking mothers, whereas the anti-PB-B2 (to phenobarbital-induced rat liver P-450) was without significant inhibitory effect. Inhibition of 7-ethoxycoumarin O-deethylase (ECDE) by the anti-BNF-B2 was dependent on maternal smoking: the enzyme from non-smokers was not significantly inhibited, whereas the enzyme from smokers was variably inhibited by 15-60 per cent. The monoclonal antibodies towards the major 3-methylcholanthrene-inducible and phenobarbital-inducible rat liver P-450s (Mab 1-7-1 and 2-66-3, respectively) behaved similarly, except the inhibition was somewhat stronger if present. Antibody raised against rat liver NADPH-cytochrome P-450 oxido-reductase did not inhibit any activity studied. In immunoblotting experiments, the anti-reductase recognized the protein in human placental microsomes. However, neither anti-BNF-B2, anti-PB-B2 or Mab 1-7-1 or Mab 2-66-3 detected any proteins in human placental microsomes, regardless of smoking status. Northern blot hybridization analysis of placental RNA samples showed that only P-450IA1 mRNA existed in the placentas of smoking mothers with detectable ERDE activity. Despite the discrepancy between protein blotting and immunoinhibition data all other findings support the conclusion that maternal cigarette smoking induces the expression of the CYPIA1 gene (and not CYPIA2), resulting in an increased synthesis of P-450IA1 protein and increased AHH, ERDE and ECDE activities in human placenta.

Preservation of platelet function during trimethaphan infusion

The effect of trimethaphan (Arfonad) infusion on platelet function was prospectively evaluated in 38 (n = 38) patients (28 patients receiving trimethaphan, ten control patients) undergoing elective cardiac surgery. Any patient with a positive history for the ingestion of medication known to interfere with platelet function was excluded from the study. Following induction of anesthesia with fentanyl (and prior to cardiopulmonary bypass) 28 patients (n = 28) received trimethaphan as clinically indicated to maintain a mean blood pressure of 80 mmHg. The infusion rate and total dose of trimethaphan delivered was recorded for each patient. The evaluation of platelet function was performed via adenosine diphosphate (ADP) and epinephrine-induced platelet aggregation tests. The administration of trimethaphan failed to result in any detrimental effect on platelet function as assessed via these aggregation studies. Template bleeding times were also performed on all study patients. Bleeding time measurements performed in patients following trimethaphan administration were unchanged from baseline values. Platelet aggregation studies and bleeding time performed in control group following the administration of fentanyl (30 micrograms/kg) plus enflurane (inspired concentration 0.5-1%) did not reveal any deviation from baseline values. These results are in contrast to a previous study that demonstrated a negative effect upon platelet function following sodium nitroprusside administration (at clinically acceptable doses). These data demonstrate that trimethaphan provides control of arterial pressure with preservation of platelet function.

Clinical applications of amrinone

A bipyridine derivative, amrinone is a noncatecholamine, nonglycoside alternative in the treatment of perioperative myocardial dysfunction. A type-3 phosphodiesterase enzyme inhibitor, amrinone combines positive inotropic support with systemic and pulmonary vasodilation. In patients with heart failure undergoing cardiac or noncardiac surgery, the absence of tachycardia and dysrhythmias is of particular clinical benefit. In these patients, amrinone's ability to augment cardiac performance without increasing heart rate or myocardial oxygen consumption offers significant clinical advantages during the perioperative period.

The Escherichia coli dam gene is expressed as a distal gene of a new operon

DNA containing the Escherichia coli dam gene and sequences upstream from this gene were cloned from the Clarke-Carbon plasmids pLC29-47 and pLC13-42. Promoter activity was localized using pKO expression vectors and galactokinase assays to two regions, one 1650-2100 bp and the other beyond 2400 bp upstream of the dam gene. No promoter activity was detected immediately in front of this gene; plasmid pDam118, from which the nucleotide sequence of the dam gene was determined, is shown to contain the pBR322 promoter for the primer RNA from the pBR322 rep region present on a 76 bp Sau3A fragment inserted upstream of the dam gene in the correct orientation for dam expression. The nucleotide sequence upstream of dam has been determined. An open reading frame (ORF) is present between the nearest promoter region and the dam gene. Codon usage and base frequency analysis indicate that this is expressed as a protein of predicted size 46 kDa. A protein of size close to 46 kDa is expressed from this region, detected using minicell analysis. No function has been determined for this protein, and no significant homology exist between it and sequences in the PIR protein or GenBank DNA databases. This unidentified reading frame (URF) is termed urf-74.3, since it is an URF located at 74.3 min on the E. coli chromosome. Sequence comparisons between the regions upstream of urf-74.3 and the aroB gene show that the aroB gene is located immediately upstream of urf-74.3, and that the promoter activity nearest to dam is found within the aroB structural gene. This activity is relatively weak (about 15% of that of the E. coli gal operon promoter). The promoter activity detected beyond 2400 bp upstream of dam is likely to be that of the aroB gene, and is 3 to 4 times stronger than that found within the aroB gene. Three potential DnaA binding sites, each with homology of 8 of 9 bp, are present, two in the aroB promoter region and one just upstream of the dam gene. Expression through the site adjacent to the dam gene is enhanced 2- to 4-fold in dnaA mutants at 38 degrees C. Restriction site comparisons map these regions precisely on the Clarke-Carbon plasmids pLC13-42 and pLC29-47, and show that the E. coli ponA (mrcA) gene resides about 6 kb upstream of aroB.

Infusion of sodium nitroprusside induces platelet dysfunction in vitro

The effect of sodium nitroprusside (SNP) infusion on platelet function was prospectively evaluated in 29 patients undergoing cardiac surgical procedures requiring cardiopulmonary bypass. Any patient receiving preoperative medication known to interfere with platelet function was excluded from this study. Platelet function was evaluated by measurement of platelet aggregation with both adenosine diphosphate (ADP) and epinephrine-induced aggregation tests. Ten patients served as a control population receiving fentanyl anesthesia and no SNP. Nineteen patients received SNP, as clinically indicated, following the induction of anesthesia (and prior to cardiopulmonary bypass) to maintain a mean blood pressure of 80 mmHg. The infusion rate and total dose of SNP delivered was recorded for each patient. Infusion rates of SNP greater than or equal to 3 micrograms.kg.-1 min-1 resulted in a dose-related decrease in platelet aggregation (P less than 0.05). This reduction in platelet function was accompanied by a concomitant increase in bleeding time from 5.8 +/- 0.6 to 9.3 +/- 0.4 min in the patients receiving SNP (P less than 0.05). In addition, with the administration of a total dose of SNP greater than or equal to 16 mg, a significant reduction in platelet aggregation (P less than 0.05) was observed. Platelet aggregation studies and bleeding time performed in the control group (following the administration of fentanyl (30 micrograms/kg) did not reveal any deviation from baseline values. The results from this in vivo study support previous in vitro data demonstrating a detrimental effect upon platelet function following SNP infusion.

A study of iron complexation in a swine model

The treatment of iron poisoning consists of supportive care and efforts to remove or retard the absorption of iron from the gastrointestinal tract. A standard but rarely challenged treatment is to render the unabsorbed iron less soluble by complexing it with bicarbonate or phosphate solution. Another therapy is the use of oral deferoxamine. Bicarbonate and phosphate therapy are known to be associated with adverse outcomes if used inappropriately. Is their use justified? To closely simulate a potentially toxic iron overdose in a 24-month-old child, a swine model was used. Twenty fasted castrated male pigs weighing an average of 14.6 kg (+/- 3.0 kg) were orally dosed with 300 mg/kg FeSO4 (60 mg Fe/kg) and randomly placed into 1 of 4 treatment groups receiving 50 ml of distilled water (control), 5% sodium bicarbonate, 5% sodium dihydrogen phosphate, or deferoxamine (10 g). Sequential serum iron levels were obtained at 0, 1, 2, 4, and 6 hr. There were no significant differences in the absorption of iron, as reflected by serum iron concentrations, in the bicarbonate and phosphate groups when compared to the control group (p greater than 0.05). Deferoxamine therapy reduced iron serum concentrations, ie iron absorption, significantly (p less than 0.05) when compared to the control, bicarbonate and phosphate groups. This study provides evidence that efforts to form digestive tract complexation of iron with bicarbonate or phosphate are of no value.

Induction of cytochrome P-450IA1 gene expression in human breast tumour cell lines

The induction of cytochrome P-450IA1 by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was studied in eight human breast tumour cell lines. The cells were treated with various concentrations of TCDD for 24 h, and total RNA was isolated. The level of P-450IA1 RNA induced by 1 nM TCDD followed the order: MCF-7 greater than T47-D greater than ZR-75-1 greater than 3909 greater than 3522. AL-1, BT-20 and CAMA-1 did not respond to TCDD at the concentrations used. Northern blot analysis revealed 2 bands at 2.7 and 2.0 Kb, respectively, with the larger band being 6-fold more intense. The ratio was not changed by the TCDD treatment. TCDD induction did not change the benzo[a]pyrene-7,8-diol (BP-7,8-diol) metabolite profile compared with control cells, when cells were incubated with [3H]BP-7,8-diol for 24 h following the treatment with TCDD. These results demonstrate that different breast tumour cell lines vary greatly with respect to the basal expression levels of P-450IA1 RNA and its inducibility by TCDD. Furthermore, TCDD treatment does not change the relative distribution of BP-7,8-diol metabolites.