Abbreviated hospitalization for deep venous thrombosis with the use of ardeparin

BACKGROUND

Ardeparin sodium has recently received approval by the Food and Drug Administration for prophylaxis against venous thromboembolism in patients undergoing elective total knee replacement. However, this low-molecular-weight heparin has not been previously evaluated in a randomized controlled trial for treatment of established acute deep venous thrombosis.

METHODS

The study included patients with ultrasound-documented acute symptomatic deep venous thrombosis of the legs. They had to be deemed appropriate for discharge home to receive subcutaneous low-molecular-weight heparin. Patients were randomized to receive ardeparin with a 2-day hospitalization or unfractionated heparin sodium with a 5-day hospitalization. Both groups received warfarin sodium. Follow-up ultrasound examinations were undertaken at 6 weeks.

RESULTS

Of the 80 patients enrolled, 75 had follow-up ultrasonography. Evaluation of baseline vs 6-week venous scans demonstrated that, overall, 31 of the 39 ardeparin-treated patients improved, compared with 21 of the 36 patients assigned to receive unfractionated heparin (P=.05). The 95% confidence interval for the difference in improvement was 0.6% to 42% in favor of ardeparin. Median charges for ardeparin and unfractionated heparin were $2815 and $6500, respectively (P<.001). There were no differences in bleeding or patient satisfaction between the 2 groups.

CONCLUSIONS

The results of this small preliminary trial suggest that ardeparin can be administered effectively and safely to selected patients with acute deep venous thrombosis and that, with proper nursing and home services, it can help decrease the duration of hospitalization.

The association of intraoperative factors with the development of postoperative delirium

PURPOSE

To examine the association of intraoperative factors, including route of anesthesia, hemodynamic complications, and blood loss, with the development of postoperative delirium.

PATIENTS AND METHODS

We studied 1,341 patients 50 years of age and older admitted for major elective noncardiac surgery at an academic medical center. Data on route of anesthesia, intraoperative hypotension, bradycardia and tachycardia, blood loss, number of blood transfusions, and lowest postoperative hematocrit were obtained from the medical record. Delirium was diagnosed by using daily interviews with the Confusion Assessment Method, as well as from the medical record and the hospital's nursing intensity index.

RESULTS

Postoperative delirium occurred in 117 (9%) patients. Route of anesthesia and intraoperative hemodynamic complications were not associated with delirium. Delirium was associated with greater intraoperative blood loss, more postoperative blood transfusions, and postoperative hematocrit <30%. After adjusting for preoperative risk factors, postoperative hematocrit <30% was associated with an increased risk of delirium (odds ratio = 1.7, 95% confidence interval 1.1-2.7).

CONCLUSIONS

Further study is required to determine whether transfusion to keep postoperative hematocrit above 30% can reduce the incidence of postoperative delirium.

Airway smooth muscle as a target of glucocorticoid action in the treatment of asthma

Glucocorticoids are highly effective in the control of asthma and suppression of airway inflammation. The cellular and molecular mechanisms involved in the anti-inflammatory actions of glucocorticoids are becoming clearer. Although it is apparent that glucocorticoids have effects on many aspects of inflammation, it is not certain which actions on which cell types are the most critical in controlling asthma. Airway smooth muscle cells represent a significant proportion of all cells present in the airways and might therefore be expected to be a prominent cellular target for inhaled steroids. Despite this, little is known of the action of glucocorticoids on airway smooth muscle. It is becoming clear that in addition to its contractile properties, airway smooth muscle can potentially contribute to the pathogenesis of asthma by increased proliferation and by expression and secretion of pro-inflammatory cytokines and mediators, which in turn may lead to the activation and recruitment of key inflammatory cells in the airways. This review examines the action of glucocorticoids on some of the diverse functions of airway smooth muscle that are implicated in remodeling of the airways in asthma. Glucocorticoids either directly or indirectly modulate contraction of airway smooth muscle by suppressing agonist-induced increases in intracellular calcium levels or by downregulating or uncoupling receptors linked to contraction (e.g., muscarinic M2 or M3, histamine H1 receptors). In addition, glucocorticoids may augment relaxation of airway smooth muscle by increasing activation of either cyclic AMP-dependent (e.g., increased expression of beta2-adrenoceptors, reduced homologous desensitization of beta2-adrenoceptors) or AMP-independent mechanisms (e.g., increased Na+/K+ electrogenic pump activity). In addition to their effects on contraction, glucocorticoids are also effective antiproliferative agents in airway smooth muscle, but under some circumstances may also contribute to proliferation by inhibiting the antiproliferative effect of high concentrations of tumor necrosis factor alpha in these cells. Glucocorticoids also suppress induction of cyclooxygenase-2 in human airway smooth muscle cells and the subsequent synthesis and release of arachidonic acid metabolites, particularly prostaglandin E2. The potential of airway smooth muscle to recruit and activate pro-inflammatory cells such as the eosinophil may also be reduced by glucocorticoids, as they are effective in preventing the release of several cytokines (e.g., RANTES, interleukin-8, and granulocyte macrophage colony-stimulating factor). The possibility exists that as we begin to understand and speculate more about the likely role of airway smooth muscle in the pathogenesis of asthma, it may be necessary to reconsider airway smooth muscle as an important cellular target for the action of glucocorticoids in the treatment of asthma.

Sample suitability for the detection of minor white cell populations (microchimerism) by polymerase chain reaction

BACKGROUND

There is increasing use of highly sensitive testing with polymerase chain reaction (PCR) to study white cell microchimerism after transfusion and transplantation. This study investigated possible artifactual sources of allogeneic sample contamination before PCR testing.

STUDY DESIGN AND METHODS

Quantitative Y-chromosome PCR was used to study microchimerism among transfused patients with sickle cell disease (SCD) and thalassemia by using residual specimens from the clinical laboratory. High levels of circulating male white cells among transfused patients with SCD but not thalassemia led to concern over the artifactual origin of male cells. To investigate, paired specimens were collected from 26 female SCD patients: one specimen underwent processing only for PCR, while the other underwent testing in the clinical laboratory before PCR as a process control. All laboratory instruments were also assessed for their ability to impart male allogeneic cells to aliquots of female blood.

RESULTS

Thirty-three (31%) of 107 SCD samples, but 0 of 20 thalassemia samples, gave a high-level PCR signal. One of 26 paired samples that was not exposed to clinical laboratory equipment had low-level PCR positivity while 10 of the 26 became strongly positive after testing on a blood cell analyzer and a reticulocyte analyzer. Sixteen of 32 female samples became positive after reticulocyte analysis, while none became positive after blood cell analysis. Samples from thalassemia patients tested PCR-negative because reticulocyte counts had not been performed.

CONCLUSION

Allogeneic cell contamination is common with clinical laboratory equipment. These samples may not be suitable for microchimerism studies. In addition to method controls, process controls should be employed where appropriate.

Distribution of neuronal intermediate filament proteins in the developing mouse olfactory system

The distribution of neuronal intermediate filament proteins in the developing mouse olfactory bulb and olfactory epithelium was characterized by immunocytochemical approach. Antibodies against alpha-internexin, neurofilament triplet proteins (NFTPs; NF-L, NF-M, and NF-H) and peripherin were used to determine their expression at different developmental stages. Alpha-internexin and peripherin were first found to be co-localized in the olfactory neuroepithelium during early development. At the perinatal stage, expression patterns of alpha-internexin and peripherin are distinguishable by spatial and temporal manner: peripherin is predominantly expressed in the olfactory nerves; whereas alpha-internexin is expressed in both olfactory nerves and olfactory bulb. Our observation suggests that peripherin as well as alpha-internexin may play some roles in the process formation of olfactory nerves during development. In the developing olfactory periglomerulus, alpha-internexin was found around postnatal Day 3, whereas NFTPs were not observed until postnatal Day 7. Our data showed that the expression of alpha-internexin preceded those of the NFTPs in most neurons of the developing olfactory bulb. Some small neurons in the adult olfactory bulb were uniquely labeled with antibody to alpha-internexin. Our results suggest that alpha-internexin may play a functional role in the neuronal cytoarchitecture of developing olfactory system, and can be a neuronal marker for detecting postmitotic migrating neurons in the adult olfactory bulb.

Immunopathology of the small-airway submucosa in smokers with and without chronic obstructive pulmonary disease

The airflow obstruction in chronic obstructive pulmonary disease (COPD) occurs mainly at the level of the small airways. In order to investigate the effect of smoking on small-airway submucosal immunopathology, we used immunohistochemistry in peripheral lung sections obtained at surgery from a group of smokers (n = 22) and from a group of nonsmokers (n = 22) that contained both ex-smokers (n = 17) and lifelong nonsmokers (n = 5). Subjects were also divided into those with (n = 19) and those without (n = 20) airflow obstruction. We found an increase in total eosinophils (p = 0.001) and activated eosinophils (p = 0.010), an increase in the CD8(+)/CD3(+) cell ratio (p = 0.003), and a decrease in the CD4(+)/CD8(+) cell ratio (p = 0.005) among cells infiltrating the small-airway submucosa in an area 50 micrometers deep to the basement membrane in smokers as compared with nonsmokers. There was also an increase in neutrophils (p = 0.019) when smokers were compared with lifelong nonsmokers. Neutrophil numbers correlated with numbers of eosinophils (p = 0.0003, r = 0.58). Furthermore, the CD8(+)/CD3(+) cell ratio was related to pack-years smoked (p = 0.016, r = 0.36), months since smoking cessation (p = 0.003, r = 0.47), and number of infiltrating eosinophils (p = 0.007, r = 0.43) and neutrophils (p = 0.004, r = 0.44). These findings suggest that smoking induces movement of an inflammatory infiltrate into the submucosa of the small airway, the location of the increased resistance to airflow in COPD.

Matrix attachment region sequences enhanced the expression frequency of a whey acidic protein/human lactoferrin fusion gene in the mammary gland of transgenic mice

To elevate the expression frequency of transgenes in transgenic mice, the chicken lysozyme matrix attachment region (MAR) sequence was used by combining it with a transgene. The whey acidic protein (WAP) promoter/human lactoferrin (hLF) cDNA fusion transgene (pWL) was connected to the chicken lysozyme MAR sequence at its 5'-end (pMWL). While only two of three mice became transgenic from the pWL vector expressed hLF, all seven mice from the pMWL vector expressed the transgene in their lactating mammary glands. To evaluate the effect of lactogenic hormones on transgene expression, experiments with the primary culture of transgenic mammary explants were performed. It was revealed that the expression of transgenes was slightly increased by insulin plus dexamethasone or insulin plus prolactin treatment. However it was not increased by insulin, dexamethasone or prolactin (IDP) treatment alone. In contrast, the endogenous WAP gene was expressed only in the IDP treated group. These results demonstrate that MAR sequences are effective in improving the expression frequency of transgenes in transgenic mice although the developmental and hormonal regulations are not the same as those of the endogenous WAP gene.

Prothrombin kringle-2 domain has a growth inhibitory activity against basic fibroblast growth factor-stimulated capillary endothelial cells

Recently, O'Reilly et al. (O'Reilly, M. S., Holmgren, L., Shing, Y., Chen, C., Rosenthal, R. A., Moses, M., Lane, W. S., Cao, Y., Sage, E. H., and Folkman, J. (1994) Cell 79, 315-328; O'Reilly, M. S., Boehm, T., Shing, Y., Fukai, N., Vasios, G., Lane, W. S., Flynn, E., Birkhead, J. R., Olsen, B. R., and Folkman, J. (1997) Cell 88, 277-285) developed a simple in vitro angiogenesis assay system using bovine capillary endothelial cell proliferation and purified potent angiogenic inhibitors, including angiostatin and endostatin. Using a simple in vitro assay for angiogenesis, we purified a protein molecule that showed anti-endothelial cell proliferative activity from the serum of New Zealand White rabbits, which was stimulated by lipopolysaccharide. The purified protein showed only bovine capillary endothelial cell growth inhibition and not any cytotoxicity. This molecule was identified as a prothrombin kringle-2 domain (fragment-2) using Edman degradation and the amino acid sequence deduced from the cloned cDNA. Both the prothrombin kringle-2 domain released from prothrombin by factor Xa cleavage and the angiogenic inhibitor purified from rabbit sera exhibited anti-endothelial cell proliferative activity. The recombinant rabbit prothrombin kringle-2 domain showed potent inhibitory activity with half-maximal concentrations (ED50) of 2 microg/ml media. As in angiostatin, the recombinant rabbit prothrombin kringle-2 domain also inhibited angiogenesis in the chorioallantoic membrane of chick embryos.

Dexamethasone inhibits ischemia-induced transient reduction of neurotrophin-3 mRNA in rat hippocampal neurons

Dexamethasone (DEX) increases the expression of neurotrophin-3 (NT-3) in normal rat hippocampal neurons, whereas transient forebrain ischemia reduces the NT-3 mRNA level. The effect of DEX on the expression of NT-3 mRNA in injured brain cells after ischemia has not been investigated, however. Using in situ hybridization and ribonuclease protection assay methods, we studied NT-3 mRNA expression in rats with and without DEX administration after transient forebrain ischemia. Without DEX treatment, NT-3 mRNA was down-regulated in the hippocampal neurons at 2, 4, 12 h and returned to basal levels 24 h following ischemia. With DEX treatment, however, NT-3 mRNA showed no change at 2, 4 and 12 h and increased 24 h after ischemia. The results indicate that DEX inhibits ischemia-induced NT-3 mRNA down-regulation during the first 12 h and up-regulates NT-3 mRNA 24 h after ischemia. DEX administration might be effective in influencing some of the pathophysiological effects of ischemia in the hippocampus.

Characterization of an immunosuppressive anti-CD40 ligand monoclonal antibody

The interaction between CD40 ligand (CD40L) and its counter-receptor CD40 is critically important in T- and B-cell costimulation and generation of the humoral immune response. But several questions still remain unsolved, particularly in the human in vivo system. To clarify the precise function of CD40L and develop an immunosuppressive agent, we have generated a murine monoclonal antibody (MAb), 2B2 specific for human CD40L. The specificity of this MAb for human CD40L was verified by enzyme-linked immunoadsorbent assay (ELISA) and flow cytometry. MAb 2B2 immunoprecipitated proteins of molecular weight 35 and 28 kD on human peripheral blood lymphocytes (PBLs) stimulated with phorbol 12-myristate-13-acetate (PMA) plus ionomycin. Then we have studied the biological effect of MAb 2B2 in severe combined immunodeficiency (SCID) mice reconstituted with human PBLs. The data showed that this MAb strongly suppressed human IgG production of human B cells transplanted in SCID mice, indicating that this MAb 2B2 could be used to regulate unwanted immune responses associated with autoimmune disease. Then we analyzed the sequence of MAb 2B2. The 2B2 heavy chain variable region (VH) and light chain variable region (VL) genes were cloned using PCR. The cloned VH gene coded for 123 amino acid residues and belonged to the subgroup III(D). The VL gene coded for 126 amino acid and belonged to the subgroup V. Collectively, these results will be used to develop an immunosuppressive chimeric or humanized anti-CD40L antibody.

Isoform expression of Na+-K+-ATPase alpha-subunit in gills of the teleost Oreochromis mossambicus

Three isoform-specific antibodies, 6F against the alpha1-isoform of the avian sodium pump, HERED against the rat alpha2-isoform, and Ax2 against the rat alpha3-isoform, were used to detect the expression of Na+-K+-ATPase alpha-subunits in gills of a teleost, the tilapia (Oreochromis mossambicus). Tilapia gill tissue showed positive reactions to antibodies specific for alpha1- and alpha3-isoforms. The results of immunoblots were converted to numerical values (relative intensities) by image analysis for comparisons. Relative amounts of alpha1-like isoform alone and consequently the ratio of alpha1-like to alpha3-like isoforms were higher in gills of seawater-adapted tilapia than in those of freshwater-adapted ones, indicating that the two isoforms respond differently to environmental salinities. In the subsequent immunocytochemical experiments, gill mitochondria-rich cells were demonstrated to immunoreact with antibodies specific for alpha1- and alpha3-isoforms. alpha1-like and alpha3-like isoforms of gill Na+-K+-ATPase are suggested to be involved in the ion- and osmoregulation mechanisms in tilapia. Moreover, differential expressions of two isoforms may be associated with different functions, secretion and uptake of ions and acid-base regulation, in gills of seawater- and freshwater-adapted tilapia.

Lhermitte-Duclos disease: first report in Taiwan

We report a case of Lhermitte-Duclos disease (dysplastic gangliocytoma of the cerebellum), an uncommon disorder of uncertain pathogenesis characterized by disarrangement of the normal cerebellar laminar cytoarchitecture. A 40-year-old man was admitted because of vomiting and syncope of a few days' duration, and a 2-month history of intermittent headaches and unsteady gait. A computed tomographic scan of the patient's head showed obstructive hydrocephalus due to displacement of the fourth ventricle by a large, nonenhancing cerebellar mass. The magnetic resonance images of the brain also revealed a space-occupying lesion within the right cerebellum with unusual septation. After surgery, the histologic examination confirmed the diagnosis of Lhermitte-Duclos disease. This is the first report of Lhermitte-Duclos disease in Taiwan.

Supraventricular arrhythmia in patients having noncardiac surgery: clinical correlates and effect on length of stay

BACKGROUND

Few recent data are available on risk factors for perioperative supraventricular arrhythmia (SVA) after noncardiac surgery or on the effect of SVA on clinical outcomes.

OBJECTIVE

To determine the incidence, clinical correlates, and effect on length of stay of perioperative SVA in patients having major noncardiac surgery.

DESIGN

Prospective cohort study.

SETTING

Urban tertiary care teaching hospital.

PARTICIPANTS

4181 patients 50 years of age or older who had major, nonemergency, noncardiac procedures and were in sinus rhythm at the preoperative evaluation.

MEASUREMENTS

Preoperative clinical data, postoperative enzyme data, serial electrocardiograms, and clinical outcomes were collected prospectively. Outcomes were 1) SVA that persisted or led to treatment and 2) increase in length of stay attributable to SVA.

RESULTS

Perioperative SVA occurred in 317 patients (7.6%); it occurred in 83 patients (2.0%) during surgery and in 256 (6.1%) after surgery. Independent preoperative correlates of SVA were male sex (odds ratio [OR], 1.3 [95% CI, 1.0 to 1.7]), age 70 years or older (OR, 1.3 [CI, 1.0 to 1.7]), significant valvular disease (OR, 2.1 [CI, 1.2 to 3.6]), history of SVA (OR, 3.4 [CI, 2.4 to 4.8]) or asthma (OR, 2.0 [CI, 1.3 to 3.1]), congestive heart failure (OR, 1.7 [CI, 1.1 to 2.7]), premature atrial complexes on preoperative electrocardiography (OR, 2.1 [CI, 1.3 to 3.4]), American Society of Anesthesiologists class III or IV (OR, 1.4 [CI, 1.1 to 1.9]), and type of procedure: abdominal aortic aneurysm (OR, 3.9 [CI, 2.4 to 6.3]) or abdominal (OR, 2.5 [CI, 1.7 to 3.6]), vascular (OR, 1.6 [CI, 1.1 to 2.4]), and intrathoracic (OR, 9.2 [CI, 6.7 to 13]) procedures. Among patients who had intrathoracic surgery, those receiving digoxin were at lower risk (OR, 0.2 [CI, 0.04 to 0.8]) for SVA than those not receiving digoxin. Patients with perioperative acute cardiac and noncardiac events had high relative risks for SVA. Supraventricular arrhythmia was associated with a 33% increase in length of stay after adjustment for other clinical data (P < 0.001).

CONCLUSIONS

In this cohort, SVA was common after noncardiac surgery and was associated with prolonged length of stay.

Expression of nerve growth factor and trkA after transient focal cerebral ischemia in rats

BACKGROUND AND PURPOSE

In vitro studies have shown that nerve growth factor (NGF) is protective to cortical neurons against various insults. However, the role of NGF in relation to its high-affinity trkA receptor in the cortical neurons has not been well discussed. In this experiment, we studied the possible involvement of the NGF/receptor system in the ischemic injury of cortical neurons after focal cerebral ischemia in rats.

METHODS

Male Wistar rats received right middle cerebral artery occlusion of 90 minutes' duration. The rats were decapitated at different reperfusion time points: hour 4 and days 1, 3, 7, and 14 of recirculation. Brain sections at the level of striatum were immunostained against NGF, trkA, glial fibrillary acidic protein (GFAP), and stress protein HSP70. Double immunostaining against NGF and GFAP was also performed. Optical density of NGF immunoreactivity in the ischemic and nonischemic cortexes was compared between sham-control and ischemic animals.

RESULTS

In the sham-control rats, NGF immunoreactivity was present in the cortical and striatal neurons. However, beginning at hour 4 after recirculation, there was a significant decrease of NGF in the ischemic cortex and striatum. Beginning at day 1, NGF was absent completely in the infarcted striatum and cortex. However, in the peri-infarct penumbra area, despite a decrease in NGF at hour 4 and day 1, NGF recovered beginning at day 3 and returned almost to the sham-control level at day 14. In the nonischemic cortex, NGF increased beginning at hour 4, peaked at day 7, and returned almost to the sham-control level at day 14. The trkA and HSP70 immunoreactivities were not present in the sham-control cortex. However, trkA was induced at hour 4 in the ischemic cortex and at days 1 and 3 in the peri-infarct penumbra cortex. The HSP70 was induced at days 1 and 3 in the peri-infarct penumbra area. Double immunostaining showed that the number of GFAP-positive cells increased gradually, and NGF immunoreactivity in the GFAP-positive cells became gradually intense after ischemia.

CONCLUSIONS

Our study demonstrated a temporal profile of NGF and trkA in the ischemic cortex and NGF expression by reactive astrocytes. Our data suggest that the NGF/receptor system may play a role in the astrocyte/neuron interaction under certain pathological conditions, such as focal cerebral ischemia.

Cardiac troponin I as a predictor of major cardiac events in emergency department patients with acute chest pain

OBJECTIVES

We sought to evaluate the diagnostic and prognostic value of cardiac troponin I (cTnI) in emergency department (ED) patients with chest pain.

BACKGROUND

Although cTnI has been shown to correlate with an increased risk for complications in patients with unstable angina, the prognostic significance of this assay in the heterogeneous population of patients who present to the ED with chest pain is unclear.

METHODS

cTnI and creatine kinase-MB fraction (CK-MB) mass concentration were collected serially during the first 48 h from onset of symptoms in 1,047 patients > or =30 years old admitted for acute chest pain. Sensitivity, specificity and receiver operating characteristic curves were calculated for cTnI and CK-MB collected in the first 24 h.

RESULTS

The sensitivity, specificity and positive predictive value of cTnI for major cardiac events were 47%, 80% and 19%, respectively. Among patients were who ruled out for myocardial infarction, cTnI was elevated in 26% who had major cardiac complications compared with 5% for CK-MB; the positive predictive value for an abnormal cTnI result was 8%. Elevated cTnI in the presence of ischemia on the electrocardiogram was associated with an adjusted odds ratio of 1.8 (95% confidence interval 1.1 to 2.9) for major cardiac events within 72 h. Among patients without a myocardial infarction or unstable angina, cTnI was not an independent correlate of complications.

CONCLUSIONS

In patients presenting to the ED with acute chest pain, cTnI was an independent predictor of major cardiac events, However, the positive predictive value of an abnormal assay result was not high in this heterogeneous cohort.

Capsaicin activates heat loss and heat production simultaneously and independently in rats

Subcutaneous administration of capsaicin (5 mg/kg) immediately increased the temperature of the tail skin (Tsk) for 2 h in urethan-anesthetized rats, suggesting an increase in heat loss. O2 consumption, an index of heat production, also immediately increased after the capsaicin injection, and this increase lasted for >10 h. Colonic temperature (Tco) decreased within 1 h after the injection, and this decrease was followed by a long-lasting hyperthermic period. Adrenal demedullation largely attenuated the capsaicin-induced increase in O2 consumption, and sympathetic denervation of the interscapular brown adipose tissue partly attenuated the increase in O2 consumption. However, capsaicin-induced heat loss was normal in these rats. In rats with cutaneous vasodilation maximized by warming and administration of hexamethonium, capsaicin did not further increase Tsk but normally induced heat production, and Tco gradually rose without a hypothermic period. Thus capsaicin simultaneously increased heat loss and heat production, and inhibition of one response did not affect the other. These findings suggest that capsaicin simultaneously activates independent networks for heat loss and heat production.