T wave alternans as a predictor of recurrent ventricular tachyarrhythmias in ICD recipients: prospective comparison with conventional risk markers

INTRODUCTION: The current standard for arrhythmic risk stratification is electrophysiologic (EP) testing, which, due to its invasive nature, is limited to patients already known to be at high risk. A number of noninvasive tests, such as determination of left ventricular ejection fraction (LVEF) or heart rate variability, have been evaluated as additional risk stratifiers. Microvolt T wave alternans (TWA) is a promising new risk marker. Prospective evaluation of noninvasive risk markers in low- or moderate-risk populations requires studies involving very large numbers of patients, and in such studies, documentation of the occurrence of ventricular tachyarrhythmias is difficult. In the present study, we identified a high-risk population, recipients of an implantable cardioverter defibrillator (ICD), and prospectively compared microvolt TWA with invasive EP testing and other risk markers with respect to their ability to predict recurrence of ventricular tachyarrhythmias as documented by ICD electrograms. METHODS AND RESULTS: Ninety-five patients with a history of ventricular tachyarrhythmias undergoing implantation of an ICD underwent EP testing, assessment of TWA, as well as determination of LVEF, baroreflex sensitivity, signal-averaged ECG, analysis of 24-hour Holter monitoring, and QT dispersion from the 12-lead surface ECG. The endpoint of the study was first appropriate ICD therapy for electrogram-documented ventricular fibrillation or tachycardia during follow-up. Kaplan-Meier survival analysis revealed that TWA (P < 0.006) and LVEF (P < 0.04) were the only significant univariate risk stratifiers. EP testing was not statistically significant (P < 0.2). Multivariate Cox regression analysis revealed that TWA was the only statistically significant independent risk factor. CONCLUSIONS: Measurement of microvolt TWA compared favorably with both invasive EP testing and other currently used noninvasive risk assessment methods in predicting recurrence of ventricular tachyarrhythmias in ICD recipients. This study suggests that TWA might also be a powerful tool for risk stratification in low- or moderate-risk patients, and needs to be prospectively evaluated in such populations.     

Developments in caries diagnosis and their relationship to treatment decisions and quality of care. ORCA Saturday Afternoon Symposium 1997

This study sought to examine the diagnostic accuracy of noninvasive prediction of accessory pathway localization in patients with manifest Wolff-Parkinson-White syndrome with the use of myocardial Doppler imaging as a new noninvasive mapping procedure. Myocardial Doppler imaging measures myocardial velocities and therefore can determine the site of earliest ventricular activation in patients with accessory bypass tracts. Twenty-five patients with manifest preexcitation were studied with the use of pulsed wave and M-mode myocardial Doppler imaging for the evaluation of the shortest electromechanical time interval in 9 basal myocardial segments. The new diagnostic test was compared with 3 electrocardiographic algorithms. An invasive mapping procedure served as reference standard. Abnormally short electromechanical time intervals were found in preexcited segments (27 +/- 12 ms vs 64 +/- 27 ms). Myocardial Doppler imaging correctly localized 84% of the accessory pathways and electrocardiographic algorithms only 48% to 60% of cases. Noninvasive prediction of accessory pathway localization by myocardial Doppler imaging is accurate and proved to be superior to prediction based on electrocardiographic algorithms.     

Proliferative activity and invasiveness among pituitary adenomas and carcinomas: an analysis using the MIB-1 antibody

Although histologically benign, one-third of all pituitary tumors will be invasive of surrounding structures. In this study, the relationship between the proliferative activity in pituitary adenomas and their invasiveness was investigated. Invasion was defined as gross, operatively or radiologically apparent infiltration of dura or bone. Using the recently developed MIB-1 monoclonal antibody, which recognizes the Ki-67 cell cycle-specific nuclear antigen, the growth fractions of 37 noninvasive adenomas, 33 invasive adenomas, and 7 primary pituitary carcinomas were determined. All tumors were fully classified by histology, immunohistochemistry, and electron microscopy. The mean Ki-67 -derived growth fractions for noninvasive adenomas, invasive adenomas, and pituitary carcinomas were 1.37 +/- 0.15%, 4.66 +/- 0.57%, and 11.91 +/- 3.41%, respectively (mean +/- standard error of the mean). An analysis of variance and then individual pairwise comparisons confirmed significant differences in the mean Ki-67 labeling index between each of the three tumor groups (P < 0.01). The mean growth fraction of hormonally active pituitary adenomas (3.25 +/- 0.26%) was significantly higher than that for nonfunctioning adenomas (2.06 +/- 0.23%) (P = 0.03). Establishing a threshold labeling index of 3% served to distinguish invasive from noninvasive adenomas with 97% specificity and 73% sensitivity and was associated with positive and negative predictive values of 96 and 80%, respectively. Although invasive pituitary tumors exhibited significantly higher growth fractions than did noninvasive tumors, there were individual exceptions, indicating that in a subpopulation of invasive pituitary tumors, factors other than proliferative activity determine invasive potential.     

Noninvasive evaluation of blunt abdominal trauma: prospective study using diagnostic algorithms to minimize nontherapeutic laparotomy

A prospective study was performed to investigate the feasibility and benefit of evaluating blunt abdominal trauma (BAT) without diagnostic peritoneal lavage (DPL) or other invasive methods. Diagnostic algorithms were designed by using ultrasonography (US) as a screening method. For unstable patients, a free fluid >/= 2 mm thickness on US images over any one of the intraperitoneal spaces (bilateral subphrenic, Morrison, and Douglas pouch) was used as an indicator for laparotomy. For stable patients, any intraabdominal free fluid detected by US was used as an indicator for further investigations. Computed tomography served as a principal complementary method. To further clarify the clinical results, the rate of nontherapeutic laparotomy (NTL) was compared with that from a previous 5-year review done before this study. During studying period of 1 year, 170 patients were consecutively enrolled. There was no delayed diagnosis, and 66 patients were found to have BAT; 17 patients were initial unstable, among whom 15 had free fluid shown by US and 13 patients had confirmed BAT. Eight of the unstable patients with free fluid on US were saved from NTL, of whom six had retroperitoneal hematoma. There was no NTL in unstable patients. Twenty-two patients underwent laparotomy. Two laparotomies done for a suspicion of bowel injury turned out to be NTL. The rate of NTL in the present study was significant lower than that in a previous review (9.1% vs. 32.2%, p = 0.025). Hence following well designed algorithms, noninvasive evaluation of BAT can proceed with safety, and NTL is minimized.     

Influence of Social Support on Adaptation to Surgery.

The authors investigated the influence of patients' social support on subjective and objective stress indicators before, during, and after surgery. The sample consisted of 42 male and 42 female patients. Social support as perceived by the patients was measured by a surgery-specific inventory with the Emotional Support and Informational Support subscales. Perioperative adaptation was assessed by self-reported anxiety, the amount of narcotics needed for anesthesia induction, and the length of the postoperative stay. Results demonstrated that patients who scored high on social support showed less anxiety, received lower doses of narcotics, and had a shorter hospital stay than did patients with low support. However, gender was a moderator of some of these associations. Compared with men, women exhibited more relationships that were in accordance with the hypotheses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Synchronous, bilateral mastectomy

Sixty-four patients (mean age, 51 years) had mastectomies which were synchronous and bilateral. Sixty-one premastectomy biopsies (bilateral, 34 and unilateral, 27) demonstrated the following: invasive carcinoma, 17; noninvasive carcinoma, 24; combination of above, 10; and benign disease, 10. Twenty-two patients had bilateral mastectomy because of bilateral positive biopsy. Twenty-nine patients with unilateral carcinoma on biopsy had bilateral mastectomy. Thirteen patients had bilateral mastectomy despite benign disease only on biopsy (10) or no biopsy (3). Ten unexpected carcinomas (34%) were found in the contralateral breast in the 29 patients with carcinoma diagnosed on unilateral biopsy. The biopsy pathology of these 10 specimens was invasive ductal carcinoma in 1 and multifocal, noninvasive carcinoma (ductal, 3 and lobular, 6) in 9. An unexpected carcinoma may be found in the contralateral breast in a significant number of patients who are selected for bilateral mastectomy, particularly if the selection is on the basis of a noninvasive, lobular histology. Bilateral mastectomy may be appropriate for such patients, particularly when complicated by a strong family history and breasts which are difficult to assess by physical or mammographic examination.     

Relationship of security of attachment to exploration and cognitive mapping abilities in 2-year-olds.

28 children aged 30–34 mo who had been assessed at 12 mo of age for security of attachment were observed exploring with their mothers in a large-scale laboratory space and were then given tasks to assess their knowledge of that space. After learning a specific route through the space to a goal, Ss were required to invent new routes to the goal. Results indicate that Ss who had been classified as securely attached explored relatively more independently and had less restricted patterns of exploration than did anxiously attached Ss. They also scored higher on tasks on spatial ability. It is proposed that individual differences in security of attachment, mode of exploration, and cognitive mapping abilities exert mutual effects on each other throughout early development. Findings indicate that security of attachment affects later competence in environmental adaptation. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Noninvasive hemodynamic monitoring of critical patients in the emergency department

OBJECTIVE: To evaluate the feasibility of multicomponent noninvasive hemodynamic monitoring in critical emergency patients and to compare this technique with simultaneous invasive monitoring by the pulmonary artery thermodilution catheter. METHODS: A prospective observational study was done comparing invasive monitoring and noninvasive monitoring in 60 critically ill or injured patients who required hemodynamic monitoring shortly after entering the ED of a university-affiliated country hospital. Cardiac output (CO) values measured by the standard thermo-dilution pulmonary artery catheter technique were compared with simultaneously obtained measurements using a noninvasive bioimpedance method. Concurrent measurements were made of pulse oximetry to screen pulmonary function and transcutaneous oximetry to assess tissue perfusion. RESULTS: The impedance CO values closely approximated those for the thermodilution method; r 0.81, p < 0.001. Significant circulatory abnormalities, including hypotension, reduced cardiac index, arterial hemoglobin desaturation, tissue hypoxia, reduced O2 delivery, and consumption, were found in 54 of the 60 (90%) patients. The cardiac index decreased in 44% of the patients, the transcutaneous O2 decreased in 39%, and the O2 saturation by pulse oximetry fell in 22% during the observation period in the ED (commonly lasting 2-8 hours). CONCLUSIONS: Noninvasive monitoring can provide hemodynamic and perfusion information previously available only by invasive thermodilution catheters. Such noninvasive monitoring can display continuous on-line real-time data, allowing immediate recognition of circulatory abnormalities and providing a means to titrate therapy to appropriate therapeutic goals.     

Dating couples' attachment styles and patterns of cortisol reactivity and recovery in response to a relationship conflict.

This study investigated theoretically predicted links between attachment style and a physiological indicator of stress, salivary cortisol levels, in 124 heterosexual dating couples. Cortisol was assessed at 7 points before and after an experimental conflict negotiation task, creating a trajectory of stress reactivity and recovery for each participant. Growth modeling of cortisol data tested hypotheses that (a) insecurely attached individuals show patterns of greater physiological stress reactions to interpersonal conflict than do securely attached individuals and (b) people with insecurely attached partners show patterns of greater stress in reaction to relationship conflict than those with securely attached partners. Hypothesis 1 was supported, but men and women differed in the type of insecure attachment that predicted stress trajectories. Hypothesis 2 was supported for men, but not for women. The discussion emphasizes the role of gender role norms and partner characteristics in understanding connections between adult attachment and patterns of cortisol responses to interpersonal stress. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparison between results of ileal conduit and continent ileal bladder (VIP), after radical cystectomy

OBJECTIVES: The aim of the present study is to analyze the results achieved with the ileal bladder according to the VIP (vescica ileale Padovana) procedure. METHODS/RESULTS: We compared the results obtained in 31 patients with invasive bladder cancer who underwent radical surgery (22 underwent the ileal conduit procedure and 9 were treated by orthotopic bladder substitution) and analyzed the early complications, long-term results and physiological data of the group submitted to the VIP procedure. In the patient group submitted to the VIP procedure, there was only one case who required removal of the new bladder due to an enteroneovesical fistula. Another case developed medium serrate anular stricture of the bulbar urethra about 8 months postoperatively and was treated by endoscopic urethrotomy. The uroradiologic and urodynamic evaluations confirmed urinary tract stability integrity of renal function and good adaptation of the new reservoir. The andrological studies showed complete sexual potency in 2 of 9 patients. CONCLUSIONS: The VIP procedure appears to be a good technique, with complications no greater than those of traditional urinary diversion, and improves the quality of life of patients undergoing radical surgery for invasive bladder cancer.     

Controversies in the use of inhaled nitric oxide therapy in the newborn

Because of the increasing incidence of tuberculosis consequent on the increasing number of patients with drug-related or HIV-induced immunosuppression, the problems of the invasive or noninvasive treatment of osteoarticular tuberculosis have come up again. While the approach aimed at the elimination of infectious foci with an adequate combination of medical therapy with a conservative treatment or surgery is still valid, the advanced technology of osteosynthesis systems and prosthetic replacement for spinal, hip and knee involvement respectively, with suitable indications, affords new solutions of surgical technique. The objective is to achieve surgical procedures that preserve at best the physiology of locomotor apparatus.     

The 'LH/HCG test', a valuable aid in the diagnosis of tubal pregnancy

174 patients with suspected tubal pregnancy were thoroughly examined. The diagnosis was confirmed in 102 women. As the usual noninvasive and invasive examination methods proved to be rather inaccurate, a new procedure, the 'LH/HCG test', was evaluated. Results were positive in all our cases. It was therefore concluded that this assay should receive primary consideration when tubal pregnancy is in question.     

Magnetic source imaging of abnormal low-frequency magnetic activity in presurgical evaluations of epilepsy

PURPOSE: Regional cortical dysfunction associated with epileptogenic activity was predicted from interictal localized abnormal low frequency neuromagnetic activity (ALFMA) using Magnetic Source Imaging (MSI). ALFMA can be detected in patients who show no interictal spikes. METHODS: A large array biomagnetometer was used in a blinded, rapid screening protocol. The MSI procedure required no alteration in epileptic medications. MSI results were compared with the presumed epileptogenic region as determined by a consensus of standard techniques, which included MR and electroclinical monitoring. RESULTS: One or more sites of localized abnormality were detected by MSI ALFMA in 29 of the 33 epileptic patients. ALFMA mapped with MSI showed a 48.5% specificity with respect to the presumed epileptogenic region. MSI ALFMA was in agreement with the final consensus as often as was ictal noninvasive video EEG monitoring, and was exceeded in specificity overall only by invasive ictal video EEG monitoring, which was required for conventional localization in 21 of the 33 patients tested with MSI. CONCLUSIONS: ALFMA measurements with MSI may augment the array of noninvasive methods used for reaching a consensus for epilepsy surgery.     

Lectin histochemistry of astrocytic tumors and in vitro characterization of lectin-induced modifications on the proliferation of the SW1088, U373 and U87 human astrocytic cell lines

The availability of a simple-to-use, automatic measurement system for noninvasive flow estimation is imperative, given the clinical demand for an acceptable noninvasive procedure rather than the standard invasive procedure of thermodilution. A method for calculating cardiac output from noninvasively derived pressure pulses has been developed, and the results of a preliminary evaluation study on post-cardiac surgery patients for whom invasive flow measures were readily available for comparison are provided in this report. The proposed method relies on fast Fourier transform (FFT) analysis of pulses measured externally at the carotid and femoral pressure points. A transfer function of the aorta is computed from digitally filtered pulse measurements, and a tapered model of the aorta is parametrically adapted using a simplex optimization algorithm so that its transfer function matches that derived experimentally. An aortic input impedance term is obtained from the optimized model and utilized along with the carotid pulse (analogous to input voltage) to compute aortic flow. In addition to its automation, attractive features of this method include the requirement for relatively few pulses for analysis as well as considerable resistance to noise artifact. For 59 data records collected from 54 post-cardiac surgery patients, the average flow measurements computed over several pulses compare well with the standard, invasive method of thermodilution. Preliminary results also indicate a strong potential for tracking changes in cardiac output over time, and invite further use of the method in monitoring hemodynamically unstable patients.     

Diagnosis of amebic dysentery by detection of Entamoeba histolytica fecal antigen by an invasive strain-specific, monoclonal antibody-based enzyme-linked immunosorbent assay

An invasive strain-specific monoclonal antibody against Entamoeba histolytica has been used in a capture enzyme-linked immunosorbent assay (ELISA) for the detection of invasive E. histolytica fecal antigen in clinical specimens and for the diagnosis of amebic dysentery in patients from Bangladesh. The fecal antigen capture ELISA (FAC-ELISA) did not cross-react with other parasite species in the clinical specimens or with noninvasive E. histolytica present in those specimens and in experimentally seeded stools. The limit of detection of the assay for invasive E. histolytica crude antigen diluted in phosphate-buffered saline or in stools was 0.58 and 3.9 micrograms/ml, respectively, which is the equivalent of approximately 72 and 487 E. histolytica trophozoites per well, respectively. The sensitivity, specificity, and efficiency of the FAC-ELISA were 87, 100, and 98%, respectively, for the detection of invasive E. histolytica antigens and 100, 100, and 100%, respectively, for the diagnosis of amebic dysentery. The FAC-ELISA is a potential alternative for the field diagnosis of amebic dysentery and for epidemiological studies to define the distribution of invasive E. histolytica.     

18F-labeled 2-deoxy-2-fluoro-D-glucose positron-emission tomography scans for the localization of the epileptogenic foci

The localization of epileptogenic foci that are amenable to curative epilepsy surgery may be accomplished by noninvasive surface electroencephalogram (EEG) recordings, clinical observations, computed tomography (CT), magnetic resonance imaging (MRI), and neuropsychologic tests. Other tests, such as invasive EEG, 18F-fluoro-deoxyglucose-positron-emission tomography (FDG-PET or PET) scans, and single-photon-emission computed tomography (SPECT) scans, have also been used at various epilepsy centers to help identify candidates who might benefit from such surgery. Interictal PET scans have demonstrated hypometabolism in areas concordant with the epileptogenic foci indicated by other diagnostic tests such as EEG and MRI. However, PET scans have also shown no abnormality in many patients with EEG-indicated epileptogenic foci; in others, the scans have shown abnormal metabolism in areas that were discordant with the epileptogenic foci. Although substitution of the noninvasive PET scan for the invasive EEG recordings would be desirable, the available data were insufficient to determine whether PET scans might serve as a reliable substitute for EEG. A positive PET scan might contribute independent information for identifying the epileptogenic site but could be noncontributory or confusing when hypometabolism is not seen or is seen in presumably normal brain areas. It is not evident from the data in the literature to what extent confirmatory PET scan findings might contribute to the management of patients with complex partial seizures.     

Noninvasive pressure support ventilation in COPD patients with postextubation hypercapnic respiratory insufficiency

Patients with chronic obstructive pulmonary disease (COPD) who have been intubated and mechanically ventilated may prove difficult to wean. Noninvasive ventilation may be used in an attempt to avoid new endotracheal intubation. The efficacy of administration of noninvasive pressure support ventilation was evaluated in 30 COPD patients with postextubation hypercapnic respiratory insufficiency, compared with 30 historically matched control patients who were treated conventionally. Patients were included in the study if, within 72 h postextubation, they presented with respiratory distress, defined as the combination of a respiratory frequency >25 breaths x min(-1), an increase in the arterial carbon dioxide tension (Pa,CO2) of at least 20% compared with the value measured after extubation, and a pH <7.35. Noninvasive pressure support ventilation was effective in correcting gas exchange abnormalities. The use of noninvasive ventilation significantly reduced the need for endotracheal intubation: 20 of the 30 patients (67%) in the control group required endotracheal intubation, compared with only six of the 30 patients (20%) in the noninvasive-ventilation group (p<0.001). In-hospital mortality was not significantly different between the two groups, but the mean duration of ventilatory assistance for the treatment of the postextubation distress, and the length of intensive care unit stay related to this event, were both significantly shortened by noninvasive ventilation (p<0.01). In conclusion, noninvasive ventilation may be used in the management of patients with chronic obstructive pulmonary disease and postextubation hypercapnic respiratory insufficiency.     

Noninvasive electrodes for electrocochleography in the chinchilla

This study compares noninvasive vs invasive electrodes for electrocochleography in chinchillas. Summating potential (SP) amplitude, action potential (AP) amplitude, and AP threshold, recorded with five types of noninvasive electrodes, were compared with simultaneous bulla recordings. Noninvasive electrodes included a needle electrode over the bulla, gold Tiptrode (Etymotic Research, Elk Grove Village, Ill), Enhancer I (Nicolet Instrument Corp, Madison, Wis), Coats (Lifetech Inc, Austin, Tex) electrode, and a locally constructed tympanic membrane (TM) electrode. Stimuli included 100-microsecond clicks and 6000-Hz tone bursts (with a 1 millisecond rise/fall time and a 5 millisecond plateau). Stimuli were initially presented at 110 dB peak equivalent sound pressure level for the clicks and 100 dB peak equivalent sound pressure level for the tone bursts. Intensity was then decreased in 10-dB decrements until no replicable AP activity was observed. The TM damping for the TM electrode was measured with 0.5, 1, 2, 4, and 6 kHz and click stimuli. The AP was clear and replicable for all electrodes used in the study, although the amplitude was substantially less for the noninvasive electrodes as opposed to the invasive electrode. The invasive electrode provided the largest amplitude SP recording, but SP could generally be clearly recorded with the needle electrode, Enhancer I, and the Coats electrode. The TM electrode and gold Tiptrode provided SP recordings less consistently. The AP threshold could be recorded with all the electrodes in the study and was generally within 10 dB of threshold recorded invasively. Electrode variables, including ease of electrode placement and potential injury, were examined. The Tiptrode and Enhancer I electrodes posed relatively few problems during placement.(ABSTRACT TRUNCATED AT 250 WORDS)     

The structure of the keratan sulphate chains attached to fibromodulin from human articular cartilage

We have previously demonstrated that fibroblasts and invasive human breast carcinoma (HBC) cells specifically activate matrix metalloproteinase-2 (MMP-2) when cultured on 3-dimensional gels of type I collagen but not a range of other substrates. We show here the constitutive expression of membrane-type 1 (MT1)-MMP in both fibroblasts, and invasive HBC cell lines, that have fibroblastic attributes presumably acquired through an epithelial-to-mesenchymal transition (EMT). Treatment with collagen type I increased the steady-state MT1-MMP mRNA levels in these cells but did not induce either MT1-MMP expression or MMP-2 activation in noninvasive breast carcinoma cell lines, which retain epithelial features. Basal MT3-MMP mRNA expression had a pattern similar to that of MT1-MMP but was not up-regulated by collagen. MT4-MMP mRNA was seen in both invasive and noninvasive HBC cell lines and was also not collagen-regulated, and MT2-MMP mRNA was not detected in any of the HBC cell lines tested. These data support a role for MT1-MMP in the collagen-induced MMP-2-activation seen in these cells. In situ hybridization analysis of archival breast cancer specimens revealed a close parallel in expression of both collagen type I and MT1-MMP mRNA in peritumoral fibroblasts, which was correlated with aggressiveness of the lesion. Relatively high levels of expression of both mRNA species were seen in fibroblasts close to invasive tumor nests and, although only focally, in certain areas close to preinvasive tumors. These foci may represent hot spots for local degradation and invasive progression. Collectively, these results implicate MT1-MMP in collagen-stimulated MMP-2 activation and suggest that this mechanism may be employed in vivo by both tumor-associated fibroblasts and EMT-derived carcinoma cells to facilitate increased invasion and/or metastasis.