Evaluation of Cumulative Effects of MR Imaging on Pacemaker Systems at 1.5 Tesla

Background: The purpose of this study was to evaluate possible cumulative effects of repeated magnetic resonance imaging (MRI) examinations on pacemaker systems in patients with cardiac pacemakers. Methods and Results: The records of pacemaker patients who underwent repetitive MRI examinations in our institution were reviewed to identify patients who underwent two or more MRI examinations at 1.5T of any anatomical region. Using these criteria, a total of 47 patients who underwent a total 171 MRI examinations were identified and included in this study. Institutional Review Board approval for all pacemaker investigations was obtained. Written informed consent was obtained from all patients. Pacemakers were interrogated immediately before and after MR imaging, and after 3 months, including measurement of pacing capture threshold (PCT), lead impedance (LI), and battery voltage (BV). PCT, LI, and BV were analyzed for changes dependant on the number of MRI exams performed. Mean changes over time and changes between first and last pacemaker interrogation of PCT, LI, and BV were calculated. A statistically significant (P < 0.05), but clinically irrelevant trend for decrease in PCT and BV was found. No significant or clinically relevant changes in LI were observed. Conclusion: In this first study, no clinically relevant, cumulative changes in PCT, LI, or BV could be detected in PM patients who underwent two or more MRI examinations. However, a careful benefit/risk evaluation, among other MRI‐ and pacemaker‐related safety precautions, remains mandatory, as clinically relevant alterations to the PM system cannot be excluded by all means.     

Tlymphocyte subsets in homosexual men from Copenhagen

Abstract. Screening of sixty-six asymptomatic homosexual men from Copenhagen revealed significantly lower Leu-3a/Leu-2a ratios as compared to controls. Ten (15%) of the homosexuals had a ratio ≤ 1·0. The low Leu-3a/Leu-2a ratios were the result of an increase in the absolute number of Leu-2a cells. Homosexuals with many partners and those who had been sexual partners of patients with the acquired immuno-deficiency syndrome (AIDS) had significantly lower ratios than those without these features. Cytomegalovirus was isolated from urine and/or sputum of 15% and this was associated with a Leu-3a/Leu-2a ratio ≤ 1·0. The observed immunological abnormalities could either represent latent infection with the putative AIDS agent or alternatively be caused by repeated infections and/or exposure to allogenic spermatocytes or lymphocytes.     

Slow Wall Motion Rather Than Electrical Conduction Delay Underlies Mechanical Dyssynchrony in Postinfarction Patients With Narrow QRS Complex

Post-MI Narrow QRS Dyssynchrony.   Introduction: The mechanism of mechanical dyssynchrony in postinfarction patients with a narrow QRS complex is not defined but essential for cardiac resynchronization therapy (CRT).
Methods and Results: Left ventricular electrical activation and subsequent wall motion were recorded for 16 patients with ischemic cardiomyopathy during intrinsic rhythm using a modified NOGA electromechanical mapping system. Ten patients presented mechanical dyssynchrony on tissue Doppler imaging, while 6 patients served as control subjects. The local activation time (LAT) was set by the maximum downslope of the unipolar electrogram. Local wall motion time (LMT) was defined as the time needed for the catheter tip to traverse half of its maximum inward deflection during systole. LAT and LMT were measured relative to the onset of the QRS complex. Electrical activation showed a septal-to-lateral pattern in all patients with a mean endocardial activation time of 65 ± 13 ms. Control subjects exhibited 97.5% of all LMTs <290 ± 17 ms. Delayed motion areas (cut-off LMT > 300 ms) showed no slowing of conduction. Wall motion time corrected for differences in electrical activation (LMT-LAT) was significantly longer in delayed (289 ± 34 ms) than in regular (204 ± 24 ms) motion areas (P = 0.002). Delayed motion segments were hypokinetic on echocardiography and presented a lower maximum inward motion (9.9 ± 1.1 mm) compared to regular segments (10.9 ± 1.2 mm) on electromechanical maps (P = 0.004). Viability, however, was preserved with unipolar and bipolar voltage amplitude >7 mV and >1.5 mV for 79% of all delayed motion areas.
Conclusion: Dyssynchronous segments of an ischemic myocardium show unimpaired local activation but slow wall motion, thereby limiting the benefit of ventricular preexcitation via CRT. (J Cardiovasc Electrophysiol, Vol. 21, pp. 70–77, January 2010)     

Antacid Treatment of Duodenal Ulcer

ABSTRACT. Becker U, Lindorff K, Andersen C, Ranløv PJ (Department of Internal Medicine B, Central Hospital, Hillerød, Denmark). Antacid treatment of duodenal ulcer. Acta Med Scand 1987; 221:95–101. Sixty-seven consecutive outpatients with endoscopically verified duodenal ulcer were randomised to a double-blind treatment with either 10 ml of an antacid suspension (buffering capacity 85 mmol/10 ml, packed in single dosage pads) 1 and 3 h after each meal and at bedtime or cimetidine 400 mg b.i.d. The double-dummy technique was employed. Endoscopy was performed after 4 weeks treatment and, if the ulcer had not healed, after 8 weeks treatment. When ulcer healing had occurred, the patient entered a 1 year follow-up study. The cumulative healing rates after 4 and 8 weeks treatment were 83 and 97% vs. 69 and 94% in the antacid and cimetidine groups respectively. No significant differences were observed between the treatment groups regarding ulcer healing, symptom relief or compliance. Adverse reactions were few and only 3 (9%) patients in the antacid group had to discontinue the treatment due to diarrhoea. Of the cimetidine treated patients, 61% had symptomatic relapse during the 1 year follow-up compared to 71% of the antacid treated patients. There were no significant differences in recurrence rate or time to relapse. The moderate dose antacid treatment used here is efficient, well tolerated, safe, convenient and is a good alternative treatment of the duodenal ulcer patient.     

In vivo uptake of fluoride by surface enamel of cleaned and plaque-covered teeth

abstract – Utilizing a newly developed biopsy method, the F uptake in the outer 3 μm of enamel from a single topical application of neutral NaF or amine F solution was tested on cleaned and plaque-covered premolars in 12- to 14-year-old children. Cleaned teeth treated with neutral NaF acquired only insignificant amounts of F. The presence of plaque seemed to enhance the deposition of F in surface enamel. The findings were discussed in relation to the possible mechanisms of action of topically applied fluorides. Topical treatments with amine F increased surface enamel F considerably more than the NaF. The F uptake was similar in cleaned and plaque-covered teeth. It was suggested that the usually performed plaque-removing procedures prior to topical F applications are superfluous and may even be disadvantageous.     

Serum human glandular kallikrein 2 (hK2) for distinguishing stage and grade of prostate cancer

BACKGROUND: Human glandular kallikrein (hK2) has been shown to add important information regarding the early detection and staging of prostate cancer. Preliminary analysis pointed out that hK2 may discriminate between pT2 and pT3 tumors, and that hK2 may predict Gleason grade 4/5 cancer volume, better than prostate-specific antigen (PSA) or percent free PSA (%fPSA). We investigated the role of hK2 serum values for predicting pathological stage, grade and Gleason score. METHODS: Prostate-specific antigen, free PSA and hK2 were measured on 222 untreated prostate cancer patients who had received radical prostatectomy at the Charité Hospital, Berlin, Germany. Pathological work up revealed pT2-cancer in 111 patients and pT3-cancer in 111 patients. Grade 2 was found in 118 patients whereas grade 3 tumors were found in 104 patients. RESULTS: For pT2 and pT3 patients, the %fPSA (P=0.006), the ratios hK2/fPSA (P=0.08) and hK2xtPSA/fPSA (P=0.002) were all significant different whereas hK2 (P=0.143) and PSA (P=0.1) did not differ. Between grade 2 and grade 3 tumors, the hK2 alone (P=0.27), the %fPSA (P=0.13), the ratios hK2/fPSA (P=0.94) and hK2xtPSA/fPSA (P=0.12) did not separate, whereas PSA (P=0.039) showed a difference. The same relationships were found between the two groups in Gleason score<7 and >or=7. Neither the hK2 ratio, nor % fPSA was different. CONCLUSION: Human glandular kallikrein was not different between pT2 and pT3, nor between G2 versus G3 or Gleason scores<7 and >or=7 prostate cancer. Together with %fPSA, hK2 may only help to distinguish preoperatively between pT2 and pT3 prostate cancer but cannot add further information.     

Long-term pulp reaction to silicate cement with an intradental control

abstract – In each of 42 clinically sound premolars scheduled for extraction for orthodontic reasons one vestibular and one lingual cavity were prepared. Four teeth were extracted immediately after cutting of the cavities for control of the effect of the cutting procedure upon the pulp. In the remaining 38 teeth one cavity was selected at random and filled with Silican® without isolation of the cavity walls and the other cavity with Pharmatec® After one hour, one week, one month, and six months the teeth were extracted and examined histologically. In this way intra-dental control of pulp reactions was possible. After an observation time of one month or less, only slight pulp damage was found under both filling materials. Following the observation period of six months obvious pulp reactions were demonstrated under both filling materials. The pulp damage following insertion of silicate cement therefore does not seem to be the result of the initial acidity of the filling material. Microorganisms were in some cases found on the cavity wall under tre silicate cement fillings. The method used was found to be preferable in comparative studies concerning the harmful effect of filling materials upon the pulp. The findings are discussed.     

Endogenous Overnight Creatinine Clearance Compared with 51 Cr-EDTA Clearance during the Menstrual Cycle

ABSTRACT Fourteen healthy women aged 21–41 years, who did not take oral contraceptives and who all had ovdatory cycles, were examined once in the follicular phase and once in the luteal phase of a single menstrual cycle. The glomerular filtration rate (⁵¹Cr-EDTA clearance) increased from the follicular to the luteal phase by a median of 7.0% (95% confidence interval: 0.7–10.3%). Endogenous overnight (22.00–08.00 hours) creatinine clearance increased by a median of 7.3% (95% confidence interval: 1.0–14.6%). The urinary creatinine excretion rate also increased with a median of 7.3% (95% confidence interval: 1.511.9%) whereas the serum concentrations of creatinine and β₂-microglobulin, urine flow and urinary excretion rate of urea did not change. The results confirm previous observations of an increase in creatinine clearance in the luteal phase of the menstrual cycle and indicate that the increase in overnight creatinine clearance reflects a true change in glomerular filtration rate.     

Mast cells in the tubal wall in women using an intrauterine contraceptive device

Summary. The number of mast cells in the tubal wall of 33 healthy non-pregnant women, 17 of whom had an intrauterine contraceptive device (IUCD), was investigated. Light microscopy showed that both the muscularis externa and the lamina propria of the tubal wall contained more mast cells in the 17 IUCD users than in the 16 non-users (control group). In both patient groups the mast cell concentration was higher in the muscularis externa than in the lamina propria. Most mast cells of the muscularis externa were more closely related to smooth muscle cells than to blood vessels. The increased number of mast cells in IUCD users may be a factor in the pathogenesis of pelvic inflammatory disease and the ectopic pregnancies that occur in IUCD users.