Comprehensive atrial fibrillation burden and symptom reduction post-ablation: insights from DECAAF II

AIMS

Traditional atrial fibrillation (AF) recurrence after catheter ablation is reported as a binary outcome. However, a paradigm shift towards a more granular definition, considering arrhythmic or symptomatic burden, is emerging. We hypothesize that ablation reduces AF burden independently of conventional recurrence status in patients with persistent AF, correlating with symptom burden reduction.

METHODS AND RESULTS

Ninety-eight patients with persistent AF from the DECAAF II trial with pre-ablation follow-up were included. Patients recorded daily single-lead electrocardiogram (ECG) strips, defining AF burden as the proportion of AF days among total submitted ECG days. The primary outcome was atrial arrhythmia recurrence. The AF severity scale was administered pre-ablation and at 12 months post-ablation. At follow-up, 69 patients had atrial arrhythmia recurrence and 29 remained in sinus rhythm. These patients were categorized into a recurrence (n = 69) and a no-recurrence group (n = 29). Both groups had similar baseline characteristics, but recurrence patients were older (P = 0.005), had a higher prevalence of hyperlipidaemia (P = 0.007), and had a larger left atrial (LA) volume (P = 0.01). There was a reduction in AF burden in the recurrence group when compared with their pre-ablation burden (65 vs. 15%, P < 0.0001). Utah Stage 4 fibrosis and diabetes predicted less improvement in AF burden. The symptom severity score at 12 months post-ablation was significantly reduced compared with the pre-ablation score in the recurrence group, and there was a significant correlation between the reduction in symptom severity score and the reduction in AF burden (R = 0.39, P = 0.001).

CONCLUSION

Catheter ablation reduces AF burden, irrespective of arrhythmia recurrence post-procedure. There is a strong correlation between AF burden reduction and symptom improvement post-ablation. Notably, elevated LA fibrosis impedes AF burden decrease following catheter ablation.

Smartphone AF Burden During the Blanking Period Predicts Catheter Ablation Outcomes: Insights From DECAAF II

BACKGROUND

Atrial fibrillation (AF) recurrence during the blanking period is under investigated. With the rise of smartphone-based electrocardiogram (ECG) monitoring, there's potential for better prediction and understanding of AF recurrence trends.

OBJECTIVES

In this study the authors hypothesize that AF burden derived from a single-lead Smartphone ECG during the blanking period predicts recurrence of atrial arrhythmias after ablation.

METHODS

630 patients with persistent AF undergoing ablation were included from the DECAAF II (Effect of MRI-Guided Fibrosis Ablation vs Conventional Catheter Ablation on Atrial Arrhythmia Recurrence in Patients With Persistent Atrial Fibrillation) trial. Patients recorded daily ECG strips using a smartphone device. AF burden was defined as the ratio of ECG strips with AF to the total number of strips submitted. The primary outcome was the recurrence of atrial arrhythmia.

RESULTS

Recurrence occurred in 301 patients during the 18-month follow-up period. In patients who developed recurrent arrhythmia after 90 days of follow-up, AF burden during the blanking period was significantly higher when compared with patients who remained in sinus rhythm (31.3% vs 7.5%; P < 0.001). AF burden during the blanking period was an independent predictor of arrhythmia recurrence (HR: 1.41; 95% CI: 1.36-1.47; P < 0.001). Through grid searching, an AF burden of 18% best discriminates between recurrence and no-recurrence groups, yielding a C-index of 0.748. After a follow-up period of 18 months, recurrence occurred in 33.7% of patients (147 of 436) with an AF burden <18% and in 79.4% of patients (154 of 194) with an AF burden >18% (HR: 4.57; 95% CI: 3.63-5.75; P < 0.001).

CONCLUSIONS

A high AF burden derived from a smartphone ECG during the blanking period is a strong predictor of atrial arrhythmia recurrences after ablation.

Effect of fibrosis regionality on atrial fibrillation recurrence: insights from DECAAF II

AIMS

The amount of fibrosis in the left atrium (LA) predicts atrial fibrillation (AF) recurrence after catheter ablation (CA). We aim to identify whether regional variations in LA fibrosis affect AF recurrence.

METHODS AND RESULTS

This post hoc analysis of the DECAAF II trial includes 734 patients with persistent AF undergoing first-time CA who underwent late gadolinium enhancement magnetic resonance imaging (LGE-MRI) within 1 month prior to ablation and were randomized to MRI-guided fibrosis ablation in addition to standard pulmonary vein isolation (PVI) or standard PVI only. The LA wall was divided into seven regions: anterior, posterior, septal, lateral, right pulmonary vein (PV) antrum, left PV antrum, and left atrial appendage (LAA) ostium. Regional fibrosis percentage was defined as a region's fibrosis prior to ablation divided by total LA fibrosis. Regional surface area percentage was defined as an area's surface area divided by the total LA wall surface area before ablation. Patients were followed up for a year with single-lead electrocardiogram (ECG) devices. The left PV had the highest regional fibrosis percentage (29.30 ± 14.04%), followed by the lateral wall (23.23 ± 13.56%), and the posterior wall (19.80 ± 10.85%). The regional fibrosis percentage of the LAA was a significant predictor of AF recurrence post-ablation (odds ratio = 1.017, P = 0.021), and this finding was only preserved in patients receiving MRI-guided fibrosis ablation. Regional surface area percentages did not significantly affect the primary outcome.

CONCLUSION

We have confirmed that atrial cardiomyopathy and remodelling are not a homogenous process, with variations in different regions of the LA. Atrial fibrosis does not uniformly affect the LA, and the left PV antral region has more fibrosis than the rest of the wall. Furthermore, we identified regional fibrosis of the LAA as a significant predictor of AF recurrence post-ablation in patients receiving MRI-guided fibrosis ablation in addition to standard PVI.

Baseline natriuretic peptides as a predictor of atrial fibrillation recurrence after radiofrequency-based pulmonary vein isolation in a non-heart failure population: A subanalysis from DECAAF II

BACKGROUND

Brain natriuretic peptide (BNP) is a marker of myocardial stretch and may have prognostic significance in patients with atrial fibrillation (AF) without heart failure (HF). We investigated the association between baseline BNP levels and arrhythmia recurrence following pulmonary vein isolation (PVI) among patients with persistent AF without HF.

METHODS

We analyzed 125 patients with persistent AF without HF who had baseline BNP measured from the DECAAF II trial. The primary outcome was arrhythmia recurrence following ablation. The baseline characteristics across the two groups were compared using Chi-square test and Wilcoxon rank test accordingly. Cox regression analysis was used to analyze the association between baseline BNP levels and the primary outcome.

RESULTS

Across the entire cohort, 64 (51%) patients experienced arrhythmia recurrence. When comparing patients who experienced arrythmia recurrence to patients who did not, patients with recurrent arrhythmia had higher levels of pre-ablation BNP, as evidenced by differences in means (330.05 pg/mL) compared to patients without recurrent arrhythmia (182.39 pg/mL) (p < .05). A cut-off BNP value of 300 pg/mL provided the largest area under curve (AUC) of receiver-operating characteristic (ROC) curve on univariate logistic regression. On unadjusted Cox analysis, for every 100 unit increase in BNP, the hazard ratio for the primary outcome increased 1.09 (1.026-1.158) times (p = .004). After adjusting for sex, hypertension, and stroke, the results remained significant (HR = 1.8516, CI 95% [1.0139 - 3.381], p = .045).

CONCLUSION

In the non-heart failure population, BNP levels predict AF recurrence following PVI in persistent AF patients.

Identifying the prognostic significance of early arrhythmia recurrence during the blanking period and the optimal blanking period duration: insights from the DECAAF II study

OBJECTIVE

Early atrial arrhythmia recurrence following atrial fibrillation (AF) ablation is common. Current guidelines promulgate a 3-month blanking period. We hypothesize that early atrial arrhythmia recurrence during the blanking period may predict longer-term ablation outcomes.

METHODS AND RESULTS

A total of 688 patients with persistent AF undergoing catheter ablation were included in the DECAAF II trial database. The primary endpoint of the study was the first confirmed recurrence of atrial arrhythmia. Recurrence was also monitored during the 90-day blanking period. A total of 287 patients experienced recurrent atrial arrhythmia during the blanking period, while 401 remained in sinus rhythm. Rates of longer-term arrhythmia recurrence were substantially higher among those who developed recurrence during the blanking period compared to those who remained in sinus rhythm throughout the blanking period (68% vs. 32%, P < 0.001). The study cohort was divided into three groups according to the timing of arrhythmia recurrence during the blanking period. Of those who had recurrent arrhythmia during the first month of the blanking period (Group 1), 43.9% experienced longer-term recurrence, compared to 61.6% who recurred during the second month of the blanking period (Group 2), and 93.3% of those who had arrhythmia recurrence during the third month (Group 3, P < 0.001). The risk of recurrent arrhythmia was highest in Group 3 (HR = 10.15), followed by Group 2 (HR = 2.35) and Group 1 (HR = 1.5). Receiver operating characteristic analysis was performed to assess the relationship between the timing of arrhythmia recurrence and the primary outcome (AUC = 0.746, P < 0.001). The optimal blanking period duration was identified as 34 days. Atrial fibrillation burden determined by smartphone electrocardiogram technology over the 18 months follow-up period was significantly higher in Group 3 (29%) compared to Groups 1 (6%) and 2 (7%) and in patients who stayed in sinus rhythm during the blanking period (5%) (P < 0.0001).

CONCLUSION

Early atrial arrhythmia recurrence during the blanking period, particularly during the third month, is significantly associated with later recurrence. Although a blanking period is warranted, it should be abbreviated.

Differences in postablation cardiac MRI scar between radiofrequency and cryoballoon ablation: A DECAAF II subanalysis

INTRODUCTION

Pulmonary vein isolation (PVI) using radiofrequency (RF) and cryoballoon (Cryo) ablation are standard approaches for rhythm control in patients with symptomatic atrial fibrillation. Both strategies create scars in the left atrium (LA). There have been few studies investigating the difference in scar formation between patients undergoing RF and Cryo using cardiac magnetic resonance (CMR) imaging.

METHODS

The current study is a subanalysis of the control arm of the Delayed-Enhancement MRI Determinant of Successful Catheter Ablation of Atrial Fibrillation study (DECAAF II). The study was a multicenter, randomized, controlled, single-blinded trial that evaluated atrial arrhythmia recurrence (AAR) between PVI alone and PVI plus CMR atrial fibrosis-guided ablation. Preablation CMR and 3- to 6-month postablation CMR were obtained to assess baseline LA fibrosis and scar formation, respectively.

RESULTS

Of the 843 patients randomized in the DECAAF II trial, we analyzed the 408 patients in the primary analysis control arm that received standard PVI. Five patients received combined RF and Cryo ablations, so they were excluded from this subanalysis. Of the 403 patients analyzed, 345 underwent RF and 58 Cryo. The average procedure duration was 146 min for RF and 103 min for Cryo (p = .001). The rate of AAR at ~15 months occurred in 151 (43.8%) patients in the RF group and 28 (48.3%) patients in the Cryo group (p = .62). On 3-month post-CMR, the RF arm had significantly more scar (8.8% vs. 6.4%, p = .001) compared to Cryo. Patients with ≥6.5% LA scar (p < .001) and ≥2.3% LA scar around the PV antra (p = .01) on 3-month post-CMR had less AAR independent of the ablation technique. Cryo caused a greater percentage of right and left pulmonary vein (PV) antral scar (p = .04, p = .02) and less non-PV antral scar (p = .009) compared to RF. On Cox regression, Cryo patients free of AAR had a greater percentage of left PV antral scar (p = .01) and less non-PV antral scar (p = .004) compared to RF free of AAR.

CONCLUSION

In this subanalysis of the control arm of the DECAAF II trial, we observed that Cryo formed a more significant percentage of PV antral scar and less non-PV antral scar compared to RF. Post ablation LA scar ≥6.5% predicted freedom from AAR, independent of ablation technique. These findings may have prognostic implications in ablation technique selection and freedom from AAR.

Atrial fibrillation ablation as first-line therapy for patients with heart failure with reduced ejection fraction (HFrEF): evaluating the impact on patient survival

INTRODUCTION

Atrial fibrillation and congestive heart failure share several pathophysiological mechanisms. As a result of their association, patients have worse outcomes than if either condition were present alone.

AREAS COVERED

While multiple trials report no significant difference between the use of pharmacological rhythm control and the use of rate control in terms of mortality and morbidity in patients with HFrEF, there is evidence to suggest that catheter ablation is beneficial in this patient population. The present review aims to provide a comprehensive overview of catheter ablation as a treatment modality for atrial fibrillation in patients with HFrEF as well as evaluate its outcome on survival.

EXPERT OPINION

An appropriate patient selection strategy for patients with HFrEF could be the next step in determining which patients might benefit most from catheter ablation. Future atrial fibrillation management may incorporate digital health and pulsed-field ablation.

Compliance challenges in a longitudinal COVID-19 cohort using wearables for continuous monitoring

BACKGROUND

Wearables to Investigate the Long Term Cardiovascular and Behavioral Impacts of COVID-19 (WEAICOR) study is a prospective observational study using continuous monitoring to detect and analyze biometrics. Compliance to wearables was a major challenge when conducting the study and was crucial for the results.

OBJECTIVE

The aim of this study is to evaluate patients' compliance to wearable wristbands and determinants of compliance in a prospective COVID-19 cohort.

METHODS

Biostrap wearable device was used to monitor participants' biometric data. Compliance was calculated by dividing the total number of days in which transmissions were sent by the total number of days in the study. Univariate correlation was performed between compliance, days in the study and age, BMI, sex, symptom severity, and number of complications/comorbidites as independent variables. Also, multivariate linear regression was then performed with days in the study as a dependent variable to assess the power of different parameters in determining days in the study.

RESULTS

On hundred twenty-two patients were included in the study. Patients were on average 43 years old and 32% were female. Age was found to be correlated with compliance (r=0.23, P=0.01). In addition, age (r=0.30, P=0.001), BMI (r=0.19, P=0.03) and severity of symptoms (r=0.19, P=0.03) were found to be correlated with days spent in the study. On multivariate analysis with days spent in the study as a dependent variable, only increased age was a significant determinant of compliance with wearables (adjusted R2 = 0.1, β = 1.6, P= 0.01).

CONCLUSIONS

Compliance is a major obstacle in remote monitoring studies and the reasons for a lack thereof are multifactorial. Patient factors such as age, in addition to environmental factors can affect compliance to wearables.

Routine postoperative laboratory tests are not required in patients undergoing elective total shoulder arthroplasty

BACKGROUND

Routine blood tests following total shoulder arthroplasty (TSA) cost the British national health system over £65,000 in 2018 without definite evidence of their impact on patients' outcomes. This study aimed to ascertain whether routine laboratory tests are necessary after elective TSA.

METHODS

A retrospective review of electronic records was completed for 274 patients that underwent TSA in the past six years. In total, 216 patients were eligible for analysis. The primary outcome was intervention rate for abnormal postoperative blood tests. Secondary outcomes were hospital length of stay (LOS), and readmissions at 30 and 90 days.

RESULTS

In total, 193 patients underwent 216 TSAs; 72% were female, and the mean cohort age was 78 ± 7.2 years. Overall, 136 patients (63%) had an abnormal postoperative blood test, however; only 8 (3.7%) required intervention. The average postoperative drop in haemoglobin (Hb) was 19g/l. In four patients (1.8%) Hb levels dropped to < 80g/l; however, only two (0.9%) were symptomatic and received a red blood cell transfusion. Six patients (2.8%) developed acute kidney injury and did not require haemofiltration. The mean LOS was 3.2 ± 2.9 days. Five patients (2.3%) were readmitted within 30 days and six patients (2.8%) within 90 days. Univariate analysis only showed association between patients with abnormal creatinine and LOS (p < 0.05), and all of these patients had raised preoperative creatinine levels.

CONCLUSIONS

Routine postoperative blood tests are not required as they did not change the clinical outcome in this cohort or the readmission rate, causing unnecessary costs. It is recommended to request postoperative blood tests for patients with raised preoperative creatinine levels.

Factors of loss to follow-up during tuberculosis treatment in a low-incidence region

OBJECTIVE

The proportion of successfully treated tuberculosis (TB) patients remains below the WHO target in France, because of a high proportion of loss to follow-up. We aimed to identify factors associated with loss to follow-up in northern France, a low-incidence area.

METHODS

Between 1997 and 2017, all consecutive patients diagnosed with TB at the Tourcoing Hospital, except those infected with multidrug-resistant or extensively drug-resistant strains, were included in a retrospective cohort study. A logistic regression analysis was performed to determine factors associated with loss to follow-up.

RESULTS

One hundred and ninety patients were included. Previous TB treatment was reported in 32 patients (17%), extrapulmonary TB in 107 (56%), and HIV infection in 44 (23%). The proportion of loss to follow-up was 15%. In multivariate analysis, the risk of loss to follow-up decreased in case of first TB treatment (OR 0.36; 95% CI: 0.14-0.92, P=0.03) and increased in non-HIV-infected patients (OR 7.67; 95% CI: 1.00-59.0, p=0.05). Support for compliance was more frequent in HIV-infected patients (23% vs. 7%, p=0.005).

CONCLUSION

The proportion of loss to follow-up was high. HIV infection was associated with a lower risk of loss to follow-up, likely to be due to more frequent support for compliance.

Potential of Raman Spectroscopy To Monitor Arsenic Toxicity on Bacteria: Insights toward Multiparametric Bioassays

In the field of toxicological bioassays, the latest progress in Raman spectroscopy opens new research perspectives on a fast method of observing metabolic responses against toxic agents. This technique offers a multiparametric approach, providing an overview of the physiological changes that are caused by pollutants. However, physiological spectral fingerprints require complex chemometric methods for proper analysis. In this study, particular attention has been given to the elaboration of an "aberrant spectra" detection strategy to highlight the effects of arsenic on the bacteria Escherichia coli. This strategy significantly improved spectra classification, consistent with a dose-response effect of the four tested concentrations of the metal. Indeed, the correct classification score of the spectra increased from 88 to more than 99%. The exposure time effect has also been investigated. The fine analysis of Raman spectroscopy fingerprints enabled the design of different "spectral signatures", highlighting early and late effects of arsenic on bacteria. The observed variations are in agreement with the expected toxicity and encourage the use of Raman spectroscopy for toxic element detection.

Computer-Guided Implant Surgery in Fresh Extraction Sockets and Immediate Loading of a Full Arch Restoration: A 2-Year Follow-Up Study of 14 Consecutively Treated Patients

Statement of Problem. Low scientific evidence is identified in the literature for combining implant placement in fresh extraction sockets with immediate function. Moreover, the few studies available on immediate implants in postextraction sites supporting immediate full-arch rehabilitation clearly lack comprehensive protocols. Purpose. The purpose of this study is to report outcomes of a comprehensive protocol using CAD-CAM technology for surgical planning and fabrication of a surgical template and to demonstrate that immediate function can be easily performed with immediate implants in postextraction sites supporting full-arch rehabilitation. Material and Methods. 14 subjects were consecutively rehabilitated (13 maxillae and 1 mandible) with 99 implants supporting full-arch fixed prostheses followed between 6 and 24 months (mean of 16 months). Outcome measures were prosthesis and implant success, biologic and prosthetic complications, pain, oedema evaluation, and radiographic marginal bone levels at surgery and then at 6, 12, 18, and 24 months. Data were analyzed with descriptive statistics. Results. The overall cumulative implant survival rate at mean follow-up time of 16 months was 97.97%. The average marginal bone loss was 0,9 mm. Conclusions. Within the limitations of this study, the results validate this treatment modality for full-arch rehabilitations with predictable outcomes and high survival rate after 2 years.

Raman spectroscopy applied to the horizontal methods ISO 6579:2002 to identify Salmonella spp. in the food industry

Food safety is a major concern for suppliers in the food chain to ensure the safety of their products. The identification procedure requested by norms is tedious, and it often requires systematic controls and qualified staff to perform the necessary analyses. Raman spectroscopy offers new opportunities to rapidly and efficiently ascertain the presence of pathogens in samples. Nevertheless, this technique requires a standardized procedure to be applied in the industrial context. Our study shows that the variability between spectral fingerprints is related to the physiological state of the microbial species and the growth phase of the bacteria plays a crucial role in its identification by Raman spectroscopy. To improve the discrimination between closely related bacterial species, a procedure based on the selection of bacterial spectra in the exponential growth phase was proposed. Different ways to introduce Raman spectroscopy in the ISO 6579:2002 standards are also proposed from the entire process to a shorter protocol. In the latter case, the identification of bacterial colonies after the selective enrichment step was proposed with the advantages of this path in terms of simplicity and rapidity (analysis time is reduced up to 50 h from the 100 h required by the standard). The protocol validated using six food categories from industrial partners have presented a good correlation by confirmation with other laboratory classical methods. In the future, this procedure could be introduced to the control system of the food production chain with a reliable database for various microorganisms encountered in this field.

A simple method of surface functionalisation for immuno-specific immobilisation of proteins

We present a new and advanced methodology, developed for surface functionalisation of gold and to study immobilisation of an immuno-specific system of proteins. A combination of electrochemical quartz crystal microbalance and Raman spectroscopy techniques allowed a complete understanding of the system starting from surface functionalisation and progressing to the functional structure analysis of immobilised proteins. A simple electrochemical procedure was formulated to prepare sulphonyl chloride terminated gold surfaces that form a strong sulphonamide bond with the receptor protein staphylococcal protein A (SpA). On the SpA grafted surfaces, the immobilisation of a human IgG and consecutive binding of an immuno-specific anti-human IgG was observed. The surface functional groups form a strong interaction with SpA without disturbing its functional properties. The native functional structure of SpA and also the IgGs was found to be retained in their immobilised state.

Traumatic occipital meningoencephalocele presenting with homonymous hemianopia in a professional driver

BACKGROUND

This study presents the case of a 32-year-old male who is a chronic headache sufferer. He is a professional driver who presented with homonymous hemianopia secondary to a traumatic occipital meningoencephalocele. This is the first time such an association has been reported.

CONCLUSIONS

The complete lack of previous visual symptoms supports the belief of late development of the hemianopia. However, the chronicity and the nature of the patients' headaches could have justified further investigations in the past.

Feasibility of bimanual microincision phacoemulsification in hard cataracts

PURPOSE

The purpose of this work was to assess the feasibility of bimanual phacoemulsification in hard cataracts of N3+ using WhiteStar technology of Soveriegn (Advanced Medical Optics, Santa Ana, CA, USA).

SETTING

Ain-Shams University Hospitals, Ophthalmology Department, Cairo, Egypt.

DESIGN

A randomized prospective noncomparative study.

METHODS

A randomized prospective study of 33 consecutive cases (N3+ or more) was conducted, phacoemulsification using a bimanual microincision technique using the Sovereign with WhiteStar technology phacoemulsification machine. One phaco mode was used in all eyes. The ultrasound power was set at 30-25% according to the hardness of the nuclei, duty cycle of 33%, flow rate of 20-28 cm3/min, and vacuum of 240 mmHg. Occlusion mode was on. Nine eyes received rollable intraocular lenses (IOL) of ThinOptx, whereas 24 eyes had been implanted with hydrophobic acrylic foldable IOL (Sensar OptiEdge SA40e of AMO) through a third incision. Study parameters were effective phacotime (EPT), presence of wound burn, degree of immediate postoperative iritis, amount of infusion solution used, and total operating time.

RESULTS

The mean EPT was 4.3 s with an average ultrasound used of 5.7%. The mean operating time was 11 min and 20 s. Although the nuclear hardness was of grade 3 or above (in a scale of 5), there were no cases of thermal burn; P=0.005. Only three eyes suffered postoperative iritis 2+, which resolved within 1 week on topical steroids, statistically nonsignificant, P=0.2. The amount of infusion solution was less than that used in conventional coaxial phaco. This technique induced considerably less corneal astigmatism than surgery using conventional corneal incisions.

CONCLUSIONS

Hard cataracts of N3 or more could be safely removed through an incision of 1.4 mm incision using bimanual micro-phaco.

Imaging of pyogenic infectious spondylodiskitis

The presence of infectious spondylodiskitis and its complications may present protean clinical and imaging findings. The frequent use of multi-imaging modalities has led to a greater sensitivity and specificity in the diagnosis of this ubiquitous disease.

Emergency MR imaging of orthopedic trauma. Current and future directions

Fast MR imaging protocols pave the way for more widespread use of MR imaging to evaluate emergency room trauma patients. This article reviews technical developments and protocols facilitating rapid imaging, conventional applications of MR imaging to evaluate soft tissue injuries, and newer applications in which MR imaging is used to image both axial and appendicular fractures.

TRP, a protein essential for inositide-mediated Ca2+ influx is localized adjacent to the calcium stores in Drosophila photoreceptors

The Drosophila transient receptor potential (trp) gene product (TRP) shows some structural similarity to vertebrate voltage-gated Ca2+ channels. It appears to function as a novel Ca2+ channel responsible for light stimulated, inositol trisphosphate (InsP3)-mediated Ca2+ entry in the fly retina. The subcellular localization of TRP protein was determined in this study using immunohistochemical staining with anti-TRP antibody (MAb83F6). TRP was localized to the base of the microvilli in a region adjacent to the presumed InsP3-sensitive Ca2+ stores. This specific localization was supported by measuring the magnitude of a TRP-dependent inward current that results from spontaneous activation of the light-sensitive channels during whole-cell recordings (the rundown current, RDC). We found that reduction of the microvilli area through genetic dissection with the opsin null mutant, ninaEora, was correlated with a pronounced enhancement of the TRP-dependent inward current relative to wild type, suggesting that the TRP-dependent current was not produced along the length of the microvilli. We suggest that the functional localization of the TRP protein is on the plasma membrane loop found along the base of the rhabdomeric microvillus. Thus, the TRP channel may function in concert with the InsP3-sensitive Ca2+ stores.

Low density lipoprotein cholesterol and whole blood viscosity

Whole blood viscosity (WBV) was measured in a normal population and was analyzed in relation to packed cell volume, (hematocrit, PCV), fibrinogen, white blood cell count (WBC), platelet count, and plasma lipids, including total cholesterol, triglycerides, high density lipoprotein cholesterol (HDLc) and low density lipoprotein cholesterol (LDLc). Conventional assays were used for all blood and lipid measurements. Whole blood viscosity was measured under disaggregating conditions with a disposable, porous bed viscometer. As expected, the strongest correlation was seen between WBV and PCV (r = 0.78, p < 0.001). Significant positive correlations also were demonstrated between WBV and cholesterol (r = 0.22, p < 0.001), triglycerides (r = 0.14, p < 0.001) and LDLc (r = 0.21, p < 0.001). A significant negative correlation was found between HDLc and WBV (r = -0.20, p < 0.001). Correlation analysis by sex showed only the correlation of LDLc was significant for both men and women. A stepwise multiple regression analysis of WBV indicated that LDLc, fibrinogen (Fbg) and platelet (Plt) counts correlated independently of PCV to WBV. The equation derived from multiple regression and partial correlation analysis was: WBV (mPa.sec) = -9.317 + 0.0047 (LDLc) + 0.381 (PCV) + 0.00152 (Plt) + 0.0021 (Fbg). The calculated mean specific contribution of PCV was 90.8 percent, LDLc 3.5 percent, and fibrinogen 3.3 percent to observed mean WBV. This study shows that LDLc is the principal lipoprotein independently influencing whole blood viscosity and its effect is similar in magnitude to fibrinogen. Further studies to elucidate the mechanism and clinical significance of the effects of LDLc on WBV are indicated.

Histopathological effects of silicone rubber 'Ovabloc' on the human fallopian tube

OBJECTIVE

To study the histopathological effects of silicone rubber on the human fallopian tube.

METHODS

A prospective longitudinal study at Benha University Hospital and Boulak Eldakrour General Hospital, Egypt. Nine patients who were on the waiting list for hysterectomy and requested postponing of their operation for personal reasons.

RESULTS

Our results suggest that silicone rubber induces histopathological changes in the form of ciliary loss and intracellular changes.

CONCLUSIONS

These effects tend to increase with the increase of the duration of tubal plugging and are best seen by electron microscopy.

A community education monitoring system: methods from the Stanford Five-City Project, the Minnesota Heart Health Program and the Pawtucket Heart Health Program

Understanding the process of behavior change interventions is critical to achieving campaign effectiveness and successful program replication. The present article presents a community education monitoring system (CEMS) using data from the Stanford Five-City Project (FCP), the Minnesota Heart Health Program (MHHP) and the Pawtucket Heart Health Program (PHHP). CEMS records the number and type of intervention activities, outcome objectives, targets of change (individual, organizational or environmental), channel(s) of dissemination and proportion of programs funded by the community. These data illustrate (1) the application of theory for each project, (2) data-based program administration, (3) feedback for revising programs and (4) type of reach or 'dose' information obtained from intervention monitoring. Process evaluations such as CEMS provide critical links between field realities and evaluation outcomes. This type of evaluation develops standards for measuring program reach and allows comparisons with other programs. CEMS also illustrates how programs enact theory. Validation studies are critical to the continued successful use of CEMS. The first step, however, is to develop a uniform way of describing complex multichannel behavior change programs. CEMS in a refined form should prove invaluable to health promotion program planners whether in research or service settings.

Removal of intrauterine devices with missing tails during early pregnancy

During a 70-month period, CO2 hysteroscopy was carried out on 52 pregnant women wearing IUDs with retracted tails. Ultrasonography was done prior to hysteroscopy to determine the size of the gestational sac and the site of the device. Successful removal of the device occurred in 46 cases. The technique, the findings of the study, and the limitations of the procedure are described.

Corticosteroids in the management of adnexal hemangiomas in infancy and childhood

Adnexal hemangiomas are common in infancy and childhood. They can be interesting to the ophthalmologist for two reasons: cosmetic and functional (the second, the more important). By their natural history, they can produce serious visual consequences by producing refractive or stimulus-deprivation amblyopia. The management of adnexal hemangiomas is a challenge. The accepted method is most instances is corticosteroid therapy. This is administered either by local, intralesional, or systemic routes; the first is preferred. Steroid therapy can cause systemic and local side effects. Furthermore, a rebound effect can occur with this type of therapy. We present the cases of 12 patients with adnexal hemangiomas treated with steroids. These patients are reviewed, with emphasis on their responses and the complications of steroid therapy.

Endoscopic management of the intrauterine septum

During 20 months of study 29 patients in whom congenital uterine anomalies were previously diagnosed by hysterosalpingography, had a combined hysteroscopy/laparoscopy procedure. In 17 cases, an intrauterine septum was cut under vision using CO2 hysteroscopy and/or optical scissors. No electrocautery or vasoconstrictor agents were needed to minimize the possibility of bleeding as the septum is of fibrous nature. No estrogen therapy was given and no IUDs were inserted post operatively. A second look hysteroscopy done 2 months later showed no intrauterine adhesions. Laparoscopic monitoring during the hysteroscopic procedure allowed avoidance of uterine perforation, assessment of the condition of the tubes and the ovaries as well as differentiation between bicornuate and septate uterus.

Hysteroscopic removal of copper-containing intrauterine devices with missing tails during pregnancy

During a 15-month period, CO2 hysteroscopy was carried out on 21 pregnant women wearing IUDs with retracted tails. Ultrasonography was done prior to hysteroscopy to determine the size of the gestational sac and the site of the device. Successful removal of the device occurred in 17 cases. The paper describes the technique, the findings of the study, and the limitations of the procedure.

Morphological study of the effects of an GnRH agonist on the canine testis after 4 months of treatment and recovery

After 4 months of treatment of adult male dogs with the GnRH agonist (GnRH-A) [D-Trp6]GnRH ethylamide, the seminiferous tubules contained only type A and B spermatogonia, Sertoli cells, and rare primary spermatocytes, thus causing a 64% decrease in testis weight. At the electron microscope level, Sertoli cells showed an increase in phagosomes and lipid droplets. Leydig cells were markedly atrophied with the accumulation of lipid droplets and showed a predominance of mitochondria with lamellar instead of vesicular cristae. Four months after cessation of treatment with GnRH-A, a complete return to normal spermatogenesis and Leydig cell morphology was observed. The full reversibility of spermatogenesis in the dog after chronic GnRH-A treatment suggests that this well-tolerated peptide could be used as a reversible method of male contraception.

Mass spectral identification of benzothiazole derivatives leached into injections by disposable syringes

Five benzothiazole derivatives leached into injections by the rubber plunger-seals of disposable syringes were identified by electron impact (EI) and chemical ionization (CI) mass spectrometry. These are 2-hydroxybenzothiazole, 2-mercaptobenzothiazole, 2-(methylmercapto)benzothiazole, 2-(2-hydroxyethoxy)benzothiazole and 2-(2-hydroxyethylmercapto)benzothiazole. 2-Mercaptobenzothiazole is used as a vulcanization accelerator. The other four compounds are formed from the zinc derivative of 2-mercaptobenzothiazole during sterilization with ethylene oxide. Toxicological, technological and legal consequences of the leaching are discussed briefly.