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B Hook

Publications and source records attributed to B Hook.

At least 19 recordsLinked to original sources
PubMed1999

Prediction of sustained ventricular tachycardia inducible by programmed stimulation in patients with coronary artery disease. Utility of clinical variables.

BACKGROUND: Cardiologists often use clinical variables to determine the need for electrophysiological studies to stratify patients for risk of sudden death. It is not clear whether this is rational in patients with coronary artery disease, left ventricular dysfunction, and nonsustained ventricular tachycardia. METHODS AND RESULTS: We analyzed the first 1721 patients enrolled in the Multicenter UnSustained Tachycardia Trial to determine whether clinical variables could predict which patients would have inducible sustained monomorphic ventricular tachycardia. The rate of inducibility of sustained ventricular tachycardia was significantly higher in patients with a history of myocardial infarction and in men compared with women. There was a progressively increased rate of inducibility with increasing numbers of diseased coronary arteries. There was a significantly lower rate of inducibility in patients with prior coronary artery bypass surgery and in patients who also had noncoronary cardiac disease. The rate of inducibility was higher in patients of white race, patients with recent (</=6 weeks) angina, left ventricular dyskinesis, and in patients with greater numbers of fixed thallium defects. Inducibility was more likely in patients who had a prior myocardial infarction complicated by congestive heart failure, ventricular tachycardia, or fibrillation </=48 hours after the onset of infarction. Although these associations are statistically significant, the accuracy of the clinical variables in discriminating between patients with and those without inducible ventricular tachycardia is only modest (receiver operator characteristic area <0.70). CONCLUSIONS: Multiple clinical variables are independently associated with inducible sustained ventricular tachycardia. However, they have limited utility to guide clinical decisions regarding the use of electrophysiological testing for risk stratification in this patient population.

Aged↗
PubMed1997

Neonatal morbidity after elective repeat cesarean section and trial of labor.

OBJECTIVE: To evaluate neonatal outcomes after an elective repeat cesarean section (ERCS) compared with a trial of labor (TOL). POPULATION AND METHOD: All mothers who underwent previous cesarean section and delivered singleton infants at term gestation were identified during a 1-year period. Neonatal outcomes were compared between infants delivered by ERCS (n = 497) and those delivered by TOL (n = 492), and between infants delivered by a successful (n = 336) and a failed (n = 156) TOL. A cohort of mothers and their term infants delivered by routine vaginal delivery were also identified. RESULTS: Infants delivered by ERCS had an increased rate of transient tachypnea compared with infants born by TOL (6% vs 3%). Compared with routine vaginal deliveries, the adjusted odds ratio of developing any respiratory problem after an ERCS was 2.3 (95% confidence interval [CI]: 1.4, 3.8), and for developing transient tachypnea was 2.6 (CI: 1.5, 4.5). In addition, two infants delivered by ERCS developed respiratory distress syndrome. Infants delivered after a TOL had increased rates of suspected and proven sepsis (5% vs 2% and 1% vs 0.1%, respectively). Compared with a successful TOL, the infants delivered by cesarean section after a failed TOL had more neonatal morbidity and had a longer hospital stay (4.8 +/- 2 vs 3.1 +/- 2 days). The odds ratio for developing any respiratory illness after a failed TOL was 2.1 (95% CI: 1.1, 4.1), for suspected sepsis was 4.8 (95% CI: 2.6, 9.0), and for proven sepsis was 19.3 (95% CI: 2.0, 187). Neonatal outcomes after a successful TOL were similar to routine vaginal births. CONCLUSION: Infants born by ERCS are at increased risk for developing respiratory problems compared with those born by TOL. However, TOL is associated with increased rates of suspected and proven sepsis. This appears to be limited to infants delivered by cesarean section after a failed TOL.

Cesarean Section, Repeat↗
PubMed1996

Heterogeneity of retrograde fast-pathway conduction pattern in patients with atrioventricular nodal reentry tachycardia: observations by simultaneous multisite catheter mapping of Koch's triangle.

BACKGROUND: Selective ablation of either the fast of the slow pathway resulting in cure of AV nodal reentry tachycardia (AVNRT) has led to the concept that these pathways are discrete, anatomically defined structures. We hypothesized that if a discrete retrograde fast pathway exists, it should be possible to record a single focus of early atrial activation near the apex of Koch's triangle, with sequential spread of depolarization to the rest of the atria. METHODS AND RESULTS: We evaluated 46 patients (33 women, 13 men; mean age, 45 +/- 17 years) undergoing electrophysiology study and catheter ablation for typical AVNRT. Retrograde atrial activation during AVNRT (337 +/- 43 ms) and ventricular pacing at a similar cycle length (352 +/- 51 ms) was recorded in the region of Koch's triangle with a decapolar catheter in the His bundle position, a multipolar catheter in the coronary sinus, and a deflectable quadripolar catheter along the tricuspid annulus anterior to the coronary sinus ostium. Earliest atrial activation was recorded at the apex of the triangle of Koch in 38 patients during ventricular pacing and in 43 patients during AVNRT. A broad wave front of atrial activation was recorded in 17 patients during ventricular pacing and in 26 patients during AVNRT. During AVNRT, only 2 patients had a single early site with focal and sequential activation along the tendon of Todaro. There was concordance in the pattern of atrial activation between ventricular pacing and AVNRT in only 21 of 46 patients. CONCLUSIONS: Retrograde atrial activation over the fast pathway is heterogeneous within Koch's triangle and the coronary sinus, both for the entire population and for individual patients during different modes of activation. These data do not support the concept of an anatomically discrete retrograde fast pathway.

Adult↗
PubMed1995

Twenty-month outcome in ventilator-dependent, very low birth weight infants born during the early years of dexamethasone therapy.

We sought to examine the effect of the introduction of dexamethasone therapy on health, growth, and neurodevelopmental outcome in very low birth weight (VLBW) infants at 20 months of age. We compared outcomes in all 86 VLBW infants (mean birth weight 871 gm, mean gestational age 26.4 weeks) who were ventilator dependent on day 21 of life during the 2 years preceding October 1988 (period 1), when dexamethasone therapy became accepted clinical practice in our unit, with outcomes in all 124 infants (mean birth weight 891 gm, mean gestational age 26.9 weeks) with similar ventilator status during the subsequent 2 years (period 2). In addition, we compared outcomes in infants who received dexamethasone during period 2 with those in a concurrent cohort of less ill infants who were not given dexamethasone. There were no significant differences between periods 1 and 2 in mortality rates after 21 days (17% vs 21%), need for home oxygen (23% vs 25%), oxygen dependence at 20 months of corrected age (11% vs 10%), rate of neurosensory impairment (24% vs 25%), and mean Bayley Mental scores (81.5 vs 77.2) or Psychomotor Development Index (81.6 vs 71.1). Infants who received dexamethasone during period 2 had significantly more severe lung disease and poorer respiratory, growth, and developmental outcomes. We conclude that VLBW infants with ventilator-dependent chronic lung disease have very poor outcomes, even when treated with dexamethasone. More information is needed from prospective, randomized trials before dexamethasone can be accepted as routine therapy for chronic lung disease.

Child Development↗
PubMed1993

ICD data storage: value in arrhythmia management.

Sophisticated diagnostic information is provided by the latest generation of implantable defibrillators. The success of therapy and the type of therapy successful in terminating ventricular arrhythmias is provided by interrogating the ICD device. In addition, R to R interval information can be retrieved. In selected devices, either local bipolar electrograms from the rate sensing leads or wide bipolar electrograms from the energy delivering leads provide visual confirmation of the presence of ventricular tachyarrthythmic events leading to therapy. The value and limitations of this sophisticated diagnostic information in providing insight into the electrical events triggering therapy and the events triggering ventricular arrhythmias are discussed.

Arrhythmias, Cardiac↗
PubMed1991

[Candida colonization in diseases of the oral mucosa: clinical observations].

The influence of Candida colonization of the oral mucosa in cases of diseases such as lichen planus mucosae and pemphigus vulgaris is demonstrated. Those colonizations which are not clinically evident may easily be overlooked. They may be one of the reasons why the treatment of the underlying diseases appears to be not effective. Repeated cultural investigations of yeasts in those diseases are necessary, especially during their sometimes prolonged therapy.

Adult↗
PubMed1987

[Value of detecting pathogens in fertility disorders].

The present study was carried out on 1092 asymptomatic male patients suffering from unexplained infertility without any history or clinical signs of inflammatory diseases of the genital tract. Semen samples were cultured for mycoplasma. In 214 of the patients, we additionally performed bacteriological investigations on seminal fluid, smears from the glans penis or prepuce, and urine specimens. Semen analysis included the common ejaculate parameters. We found significantly elevated counts of mycoplasma in 13% of the semen samples examined; pathogenic isolation rates of bacteria were observed in 36%. Increased counts of various bacterial species associated with high numbers of mycoplasma seem to be one of the causative factors in male infertility. There was not observed any close relationship between the recovery of microorganism and poor semen quality, except for fructose and citrate. When follow-up investigations were carried out in untreated patients, the concentrations of mycoplasma and bacteria in the semen fluid revealed a spontaneous variability of considerable extent, indicating frequent contamination of the semen. Therefore, we recommend to perform a culture control test of the semen prior to specific antibiotic treatment.

Adult↗
PubMed1985

[Education of the dermatologist in medical mycology].

Principal considerations on graduate medical education in mycology revealed that it should be more effective. For this purpose, an intensive training program has been performed at our department. Here we report on our experiences with this conception as well as our conclusions drawn from it.

Curriculum↗
PubMed1984

[Differential diagnosis of partial lipodystrophies].

Based on recently published findings there can be differentiated three disease entities of partial lipodystrophies. We report on two special courses differing from the progressive lipodystrophy by sparing the face. The main clinical and laboratory findings as well as pathogenetic concepts are discussed.

Adult↗
PubMed1984

[Partial lipodystrophy syndrome (Dunnigan type)].

Special forms of partial lipodystrophy, which in contrast to the progressive lipodystrophy of Barraquer-Simons spare the face, have been reported by Dunnigan and Köbberling. Lipodystrophy of the Dunnigan type affects the trunk and limbs; in lipodystrophy of the Köbberling type the loss of subcutaneous fat is restricted to the extremities. The following case report deals with the main clinical and laboratory findings in lipodystrophy of the Dunnigan type.

Acanthosis Nigricans↗
PubMed1983

Effects of T-2 mycotoxin on bovine serum proteins.

Mycotoxin T-2 (0.5 mg/kg of body weight) was administered orally to mixed-breed beef calves. Serum protein fractions, immunoglobulin (Ig) G, IgM, and several complement protein concentrations were studied in control and toxin-treated calves. Total protein, albumin, and globulin concentrations all decreased in toxin-treated calves as compared with that in controls. Similarly, the concentrations of alpha-, beta 1-, and beta 2-globulin fractions were reduced in the toxin-treated calves more than those in controls. The IgG and IgM values were lower in toxin-treated calves than those in the controls. Complement proteins Bbov (of the alternate pathway) and the 3rd component of complement were lower in the toxin-treated calves. The fragment of Bbov activation, B gamma 2, was increased after toxin treatment, indicating that activation of the alternate complement pathway was responsible for at least some of the reduction of the 3rd component of complement.

Animals↗
PubMed1982

The effect of T-2 toxin on the bovine immune system: cellular factors.

The effect of T-2 toxin, a Fusarium metabolite, on the bovine cellular defense (immune) system was evaluated during high levels, chronic administration. The administration of T-2 toxin to calves at the rate of 0.6 mg/kg/day was associated with significant depression of lymphocyte responses to mitogens and significant decreases in chemotaxic migration of neutrophils.

Animals↗
PubMedDate not supplied

[Therapeutic results with tamoxifen in oligospermia. II. Hormonal analysis and semen parameters].

During a five months lasting treatment with tamoxifen (2 X 10 resp. 2 X 20 mg daily) a significant increase of testosterone, LH, FSH, estradiol, free testosterone and SHBG was found. The prolactin levels diminished. In semen analysis the values of pH and fructose decreased within the normal range. The sperm density increased significantly, but we could not ascertain whether a dosage of 2 X 20 mg/die will provide better therapeutic results. Furthermore the hormonal and seminal investigations described in this paper did not allow to predict those patients who would be good responders on tamoxifen therapy. Tamoxifen seems to be effective in normo-, but also in hypo- and hypergonadotropic patients.

Estradiol↗
PubMedDate not supplied

[Tamoxifen treatment of oligospermia. Mechanism of action and metabolism].

210 males with idiopathic oligozoospermia or oligo-astheno-teratozoospermia were treated with tamoxifen (2 X 10 resp. 2 X 20 mg daily) over a period of five months. Investigations which were performed concomitantly revealed no significant changes in body weight, blood pressure, blood sedimentation rate, red and white blood count including the number of thrombocytes. In the multi-analysis of serum we found significant differences within the normal range concerning the following parameters: creatinine, albumin, cholesterol, phosphorus, sodium, calcium, alkaline phosphatase, LAP and gamma-GT. Most of those changes in serum values could be explained by an anabolic metabolism due to an increased testosterone level and by additional stress of the liver function. On 41 of those patients an ultrasonography of the testes was performed; in more than 50% the testicular volume increased during therapy with tamoxifen.

Adult↗