Biomedical subjects

N Krause

Publications and source records attributed to N Krause.

At least 37 records · Page 2Linked to original sources

PubMed2000

Standing at work and progression of carotid atherosclerosis.

OBJECTIVES: The association between the amount of standing at work and the progression of carotid intima media thickness (IMT) was studied among 584 active working men participating in the Kuopio Ischemic Heart Disease Risk Factor Study. METHODS: Ultrasound measurements of atherosclerotic changes in the carotid arteries were performed at the beginning of the study and after 4 years. Analyses of changes in IMT included adjustments for risk factors and stratification by base-line levels of atherosclerosis and prevalent ischemic heart disease (IHD). RESULTS: Significant relationships were found between the amount of standing at work and atherosclerotic progression. After adjustment for the heaviness of the work, psychosocial job factors, income, and biological and behavioral risk factors, the mean change in maximum IMT for those standing not at all, a little, a lot, and very much was 0.24, 0.25, 0.28, and 0.33 mm, respectively. For men with IHD the respective changes were 0.08, 0.15, 0.37, and 0.75 mm -- a 9-fold difference between the no-exposure and high-exposure group. For the men with carotid stenosis, the respective difference was 3-fold. CONCLUSIONS: These findings provide the first empirical support in a population study for the role of hemodynamic factors in the progression of atherosclerosis induced by long-term standing. Men with carotid stenosis or IHD appear especially vulnerable to the adverse effects associated with standing at work. Reducing the duration of standing at work should be considered both in the occupational rehabilitation of such patients and in the primary prevention of atherosclerosis.

Adult↗

PubMed2000

Standing at work and varicose veins.

OBJECTIVES: This study attempts to determine whether or not prolonged standing at work involves an excess risk for the occurrence of varicose veins. METHODS: A cohort of 1.6 million 20-to-59-year-old Danes gainfully employed in 1991 were followed for 3 years according to first hospitalization due to varicose veins of the lower extremities. The exposure data came from a representative sample of the baseline population. Altogether 5940 people were interviewed about occupational exposure and confounding factors. RESULTS: For men working mostly in a standing position, the risk ratio for varicose veins was 1.85 [95% confidence interval (95% CI) 1.33-2.36] in a comparison with all other men. The corresponding risk ratio for women was 2.63 (95% CI 2.25-3.02). The results were adjusted for age, social group, and smoking. CONCLUSIONS: Working in a standing position is associated with subsequent hospitalization due to varicose veins for both men and women.

Adult↗

PubMed1999

Synthesis of the First

A "true" allenophane with several rings and allenic bridges was synthesized. The key step in the preparation of 1 was the cyclization to a 28-membered macrocycle (52 % yield) starting from a linear molecule, which already contains three of the four allene units.

Journal Article↗

PubMed1999

Alternative approaches for measuring duration of work disability after low back injury based on administrative workers' compensation data.

BACKGROUND: Studies of low back pain (LBP) disability remain largely incomparable because of different outcome definitions. To date, systematic comparisons of alternative outcome measures have not been made. METHODS: Duration of work disability was studied in a 3-year cohort of 850 workers' compensation LBP claimants. Eleven administrative outcome measures were compared using Kaplan-Meier estimates of the proportion of claimants still on disability benefits during 3.5 years of follow-up. RESULTS: The estimated mean duration of work disability was 75 days for the first temporary disability (TD) episode, 108 days for cumulative time on TD, and 337 for total compensated days, which includes all types of wage replacement benefits during vocational rehabilitation, temporary and permanent disability. CONCLUSIONS: Commonly used administrative measures of lost workdays--time to first return to work and time on temporary disability--substantially underestimate the duration of work disability compared to measures based on all wage replacement benefits.

Adult↗

PubMed1999

Duration of work disability after low back injury: a comparison of administrative and self-reported outcomes.

BACKGROUND: Workers' compensation wage replacement data have recently been used to estimate time to return to work (RTW) and the number of work days lost after occupational injury. The degree to which indemnity-based measures reflect self-reported work disability has until now not been studied. METHOD: Kaplan-Meier curves of administrative and self-reported measures of duration of work disability were compared within a sample of 433 low back injury claimants followed up for 1 to 3.7 years. RESULTS: Administrative measures consistently and significantly underestimated the duration of disability when compared to self-reported measures of RTW. The difference between the estimated mean number of work days lost for comparable administrative and self-reported measures ranged from 142 to 334 days. CONCLUSIONS: Number of work days lost after low back injury is substantially underestimated by measures based on the duration of wage replacement benefits. This calls into question the adequacy of indemnity benefits and underscores the need for disability prevention programs.

Adult↗

PubMed1999

Diagnostic potential of combined transthoracic echocardiography and x-ray computed tomography in suspected aortic dissection.

BACKGROUND: Transesophageal echocardiography (TEE) and magnetic resonance imaging (MRI) are considered optimal diagnostic methods in the setting of suspected aortic dissection. However, although less sensitive as single modalities, transthoracic echocardiography (TTE) and contrast-enhanced computed tomography (x-ray CT) are more widely available and less costly. HYPOTHESIS: This study was undertaken to compare the diagnostic performance and reliability of the combined use of TTE and x-ray CT with TEE and/or MRI findings in the setting of suspected aortic dissection. METHODS: The diagnostic power of combined TTE and x-ray CT was compared with both single use of TTE and x-ray CT and with TEE and/or MRI in a series of 168 consecutive patients with suspected aortic dissection (AD). Of these, 28 women and 58 men (mean age 53 +/- 16 years) underwent TTE and x-ray CT prior to TEE (n = 52) and/or MRI (n = 69). Diagnostic results of combined TTE/x-ray CT were retrospectively but independently reevaluated in blinded fashion; diagnostic findings were validated by angiography (n = 63), surgery (n = 52), or autopsy (n = 7). RESULTS: Type A dissection was found in 29 patients (34%), type B dissection in 10 (12%), whereas aortic dissection was excluded in 47 (55%). With 95%, the sensitivity of TTE and x-ray CT was significantly enhanced when used in a combined access compared with 67 and 79%, respectively, when used as single methods (95%; p < 0.05). Sensitivity and specificity (95 and 91%, respectively) of combined TTE/x-ray CT evaluation were not different from TEE and/or MRI (100 and 96%, respectively; NS). Thrombus formation, side-branch involvement, aortic regurgitation, pericardial effusion or mediastinal hematoma were also detected with similar sensitivities and specificities both by combined TTE/x-ray CT and TEE and/or MRI. CONCLUSION: This first controlled study comparing the combined information of TTE and x-ray CT with TEE and/or MRI revealed a similar diagnostic potential of both diagnostic strategies in the setting of suspected aortic dissection. Thus, in an environment with access to color Doppler TTE and x-ray CT only, the information from both tests should be combined to decide on diagnostic management of these patients.

Aortic Dissection↗

PubMed1999

Endoscopic axillary lymphadenectomy without prior liposuction. Development of a technique and initial experience.

BACKGROUND: A new technique of endoscopic axillary lymphadenectomy without prior liposuction was developed by our group. METHOD: A total of 33 patients with early stage breast cancer were treated by breast-conserving therapy and endoscopic axillary lymphadenectomy. RESULTS: The median duration of the operation was 74.9 min (range, 30-130). Operation time was significantly shorter for the last 17 patients (p < 0.05) than for the first 16 patients. There were no intraoperative complications. The median number of removed lymph nodes was 14.5 (range, 2-28). Postoperatively three patients developed a seroma, one of which required evacuation. At postoperative day 5, arm mobility was unrestricted in 26 patients (78.7%); nine patients (27.2%) reported a loss of sensation in the outer side of the upper arm related to dermatome C5. One patient developed a temporary alar scapula, and one patient developed an axillary abscess 9 weeks after axillary lymphadenectomy during radiation therapy. After a median follow-up of 4.6 months seven patients reported persistent impairment of sensation, but all patients had regained full shoulder mobility. CONCLUSION: Endoscopic axillary lymphadenectomy can be done safely without prior liposuction.

Adult↗

PubMed1999

Stress and the devaluation of highly salient roles in late life.

OBJECTIVE: To see whether older adults cope with stress in highly salient roles by devaluing the importance of the role in which the event emerged. METHODS: Interviews were conducted with a nationally representative sample of elderly people at two points in time: 1992-1993 and 1996-1997. Complete data are available for 589 older adults. Respondents were asked to identify which of eight roles they value most highly at both points in time. Information on the number of stressful events arising in each role was also obtained. RESULTS: The findings indicate that elderly people are less likely to devalue highly salient roles when stressful events are encountered in them. DISCUSSION: The results suggest that instead of turning away from highly cherished roles when stressful life events arise, older adult may become more committed to them.

Adaptation, Psychological↗

PubMed1999

Aging, religious doubt, and psychological well-being.

The purpose of this study is twofold: (a) To see whether religious doubt is related to psychological well-being and (b) to test for age differences in the relationship between these constructs. The data come from a national sample of Presbyterians. The findings suggest that doubt is associated with greater psychological distress and diminished feelings of well-being. Moreover, the results reveal that the deleterious effects of doubt are greater for younger than for older people. Implications for practice with adults across the life span are suggested.

Adaptation, Psychological↗

PubMed1999

Religion, social support, and health among the Japanese elderly.

We address three issues in this paper: (1) Is religion related to self-rated health, (2) do these salubrious effects arise because religion encourages people to provide help to significant others, and (3) is the relationship between religion and helping others more evident among older men than elderly women? We analyze the relationships among religion, support giving, and health with data provided by a national probability sample of 2,153 older people in Japan who were interviewed face-to-face in 1996. Greater involvement in religion is associated with providing help to others more often, but these effects emerge for older men only. Regardless of gender, elders who provide assistance to others more often rate their health more favorably than older adults who are less involved in helping others. These results confirm that religion is related to health, and that helping others may explain at least part of the reason for this relationship.

Age Factors↗

PubMed1998

Psychosocial job factors, physical workload, and incidence of work-related spinal injury: a 5-year prospective study of urban transit operators.

STUDY DESIGN: Five-year prospective cohort study of 1449 transit operators. OBJECTIVES: To investigate psychosocial job factors as predictors of work-related spinal injuries, controlling for current and past physical workload. SUMMARY OF BACKGROUND DATA: The association between psychosocial job factors and spinal disorders may be confounded by physical workload. A 1991 prospective study of Boeing workers found psychosocial but not physical factors to be associated with spinal injuries. However, data on physical workload were limited. Recent cross-sectional studies of transit drivers showed both physical and psychosocial factors to be independently associated with back and neck pain. This study was designed to test these findings prospectively. METHODS: Spinal injuries were ascertained from workers' compensation records, employment history from company records, and psychosocial factors from questionnaires. Logistic regression models adjusted for age, gender, height, weight, vehicle type, and current and past physical workload. RESULTS: During follow-up, 320 drivers reported a first spinal injury. Spinal injury was predicted by psychological job demands (odds ratio [OR], 1.50; 95% confidence interval [CI], 1.33-1.95); job dissatisfaction (OR, 1.56; 95% CI, 1.09-2.23); and the frequency of job problems (OR, 1.52; 95% CI, 1.02-2.26). Marginally significant associations were found for low supervisor support (OR, 1.30; 95% CI, 0.99-1.72) and female gender (OR, 1.49; 95% CI, 0.95-2.32). Compared with full-time work, part-time work was associated with a 2.7-fold reduced risk for spinal injury (OR, 0.37; 95% CI, 0.15-0.93). Cable car crews performing the heaviest physical labor had a threefold increased risk of spinal injury compared with bus drivers (OR, 3.04; 95% CI, 1.85-5.00). CONCLUSIONS: Physical workload and psychosocial job factors both independently predict spinal injury in transit vehicle operators.

Accidents, Occupational↗

PubMed1998

High-Resolution High-Count-Rate X-ray Spectroscopy with State-of-the-Art Silicon Detectors.

For the European X-ray multi-mirror (XMM) satellite mission and the German X-ray satellite ABRIXAS, fully depleted pn-CCDs have been fabricated, enabling high-speed low-noise position-resolving X-ray spectroscopy. The detector was designed and fabricated with a homogeneously sensitive area of 36 cm(2). At 150 K it has a noise of 4 e(-) r.m.s., with a readout time of the total focal plane array of 4 ms. The maximum count rate for single-photon counting was 10(5) counts s(-1) under flat-field conditions. In the integration mode more than 10(9) counts s(-1) can be detected at 6 keV. Its position resolution is of the order of 100 micro m. The quantum efficiency is higher than 90% from carbon K X-rays (277 eV) up to 10 keV. New cylindrical silicon drift detectors have been designed, fabricated and tested. They comprise an integrated on-chip amplifier system with continuous reset, on-chip voltage divider, electron accumulation layer stabilizer, large area, homogeneous radiation entrance window and a drain for surface-generated leakage current. At count rates as high as 2 x 10(6) counts cm(-2) s(-1), they still show excellent spectroscopic behaviour at room-temperature operation in single-photon detection mode. The energy resolution at room temperature is 220 eV at 6 keV X-ray energy and 140 eV at 253 K, being achieved with Peltier coolers. These systems were operated at synchrotron light sources (ESRF, HASYLAB and NLS) as X-ray fluorescence spectrometers in scanning electron microscopes and as ultra low noise photodiodes. The operation of a multi-channel silicon drift detector system is already foreseen at synchrotron light sources for X-ray holography experiments. All systems are fabricated in planar technology having the detector and amplifiers monolithically integrated on high-resistivity silicon.

Journal Article↗

PubMed1998

Laparoscopic assistance for extended radicality of radical vaginal hysterectomy: description of a technique.

OBJECTIVE: We developed and standardized a surgical technique, which allows radical hysterectomy by a combined laparoscopic and vaginal approach with radicalness equivalent to a type III procedure according to Rutledge. METHOD: Thirty-six consecutive patients with cervical cancer stage IB1-IIIA with high risk for parametrial involvement were treated between May 1996 and March 1998. RESULTS: Bilateral para-aortic and pelvic lymphadenectomy and resection of the cardinal ligaments was performed laparoscopically using bipolar coagulation. Dissection of the ureters and resection of bladder pillars and uterosacral ligaments was performed transvaginally. On average 6.5 cm of cardinal ligament could be removed per side. CONCLUSIONS: With the laparoscopic-vaginal technique described a radical hysterectomy type III can be performed.

Adenocarcinoma↗

PubMed1998

Laparoscopic para-aortic and pelvic lymphadenectomy: experience with 150 patients and review of the literature.

OBJECTIVE: The clinical usefulness of laparoscopic pelvic and para-aortic lymphadenectomy for staging and therapy of gynecological cancer was analyzed prospectively. METHOD: Laparoscopic para-aortic and pelvic lymphadenectomy was performed in 150 patients with cervical (n = 96), endometrial (n = 41), or ovarian cancer (n = 13). Lymphadenectomy was combined with laparoscopically assisted vaginal radical hysterectomy in 70 patients, with laparoscopically assisted vaginal hysterectomy and/or bilateral salpingo-oophorectomy and/or appendectomy and/or omentectomy in 24 patients, with trachelectomy in 2 patients, and with laparoscopic radical hysterectomy in 2 patients; lymphadenectomy alone was performed in 52 patients. Right-sided para-aortic lymphadenectomy extended to the level of the right ovarian vein; left-sided dissection reached the level of the inferior mesenteric artery. In ovarian tumors, dissection was extended to the level of the renal vessels; in addition, the ovarian vessels were removed with the surrounding tissue. Peri- and postoperative data were collected prospectively to monitor progress of surgical performance. RESULTS: Mean operative time was 36 min (15-105 min) for right-sided para-aortic and 24 min (12-49 min) for left-sided para-aortic lymphadenectomy; bilateral pelvic lymphadenectomy took 64 min (44-110 min). On average 26.8 (10-56) pelvic lymph nodes and 7.3 (0-19) para-aortic lymph nodes were sampled. Major vessels were injured in 7 patients of which 4 patients required laparotomy. Patients undergoing lymphadenectomy alone were admitted for 3.2 days on average. CONCLUSIONS: Laparoscopic para-aortic and pelvic lymphadenectomy is effective for staging and treatment of gynecologic cancers.

Adult↗

PubMed1998

Left-sided suprarenal retrocrural para-aortic lymphadenectomy in advanced cervical cancer by laparoscopy.

OBJECTIVE: Conventional open suprarenal retrocrural lymphadenectomy is done via a thoraco-abdominal approach including partial rib resection. We developed a less invasive technique. METHODS: Through a laparoscopic transperitoneal approach the left paracolic peritoneum and the left phrenicocolic ligament are transected. The colonic flexure, left kidney with adrenal, tail of the pancreas, and spleen are mobilized and retracted medially. The suprarenal aorta with superior mesenteric artery and coeliac trunk are exposed. The crus of the diaphragm and the right inferior phrenic artery are transected. This allows lymphadenectomy from the level of the left renal vessels to the crus of the diaphragm. RESULTS: In October 1997 three women with cervical cancer stage IIIB underwent laparoscopic suprarenal retrocrural lymphadenectomy. A mean of 10 lymph nodes was removed (range 8-12). Duration of operation was on average 218 min (range 196-258 min). Intraoperative blood loss was estimated between 100 and 400 ml and hospital stay was 4 days on average. There were no intra- or postoperative complications. CONCLUSION: This laparoscopic technique may prove useful for staging and treatment of women with advanced gynecologic cancer.

Adult↗

PubMed1998

Left-sided laparoscopic para-aortic lymphadenectomy: anatomy of the ventral tributaries of the infrarenal vena cava.

OBJECTIVE: We evaluated the anatomy of the infrarenal portion of the human inferior vena cava and their ventral tributaries by video laparoscopy. STUDY DESIGN: A total of 112 patients underwent laparoscopic para-aortic lymphadenectomy for gynecologic malignancies. All procedures were videotaped. The number and anatomic distribution of the infrarenal tributaries of the anterior part of the inferior vena cava was evaluated retrospectively from videotapes. The inferior vena cava was divided into 3 levels: the area of the bifurcation of the vena cava (level 1), the area between the bifurcation and the inferior mesenteric artery (level 2), and the area between the inferior mesenteric artery and the right ovarian vein (level 3). RESULTS: Tributaries were found in level 1 in 65 (58%) patients, in level 2 in 22 (19.6%) patients, and in level 3 in 1 (0.9%) patient; in 24 (21.5%) patients no tributaries were found. A total of 237 tributaries was counted: 82.3% (195 of 237) were located at level 1, 17.3% (41 of 237) at level 2, and 0.4% (1 of 237) at level 3. Patients with tributaries had a mean of 3 tributaries in level 1, a mean of 1.7 tributaries in level 2, and 1 patient had 1 tributary in level 3. CONCLUSIONS: The ventral tributaries of the inferior vena cava show a specific distribution pattern. The knowledge of these anatomic landmarks can be important for laparoscopic surgeons to avoid accidental injury.

Adult↗

PubMed1998

Value of laparoscopic evaluation of paraaortic and pelvic lymph nodes for treatment of cervical cancer.

OBJECTIVE: Laparoscopy was used to identify and localize suspicious lymph nodes in patients with cervical cancer. STUDY DESIGN: Eighty-four patients with cervical cancer International Federation of Gynecology and Obstetrics stage IA2 to IV were staged by laparoscopic paraaortic and pelvic lymphadenectomy. The accuracy of laparoscopic assessment of lymph node status was compared with the histologic result. Positive lymph nodes were localized topographically by use of laparoscopy. RESULTS: Sensitivity and specificity of laparoscopic evaluation for identifying positive paraaortic and pelvic lymph nodes was 92.3%. Combination of laparoscopic evaluation and frozen section helped to diagnose all patients with involved lymph nodes correctly. In 13 of 84 (15.4%) patients the result of lymph node assessment by laparoscopic evaluation and frozen section changed primary therapy. In two of these patients one positive lymph node was located in the lateral part of the cardinal ligament, and the hysterectomy was extended to be a more radical procedure. CONCLUSIONS: Laparoscopic evaluation identified the lymph node status in patients with cervical cancer with high accuracy. Topographic localization showed that the lateral part of the cardinal ligament is involved early in lymph node spread.

Aorta↗

PubMed1998

Identification of the ureter and dissection of the bladder pillar in laparoscopic-assisted radical vaginal hysterectomy.

BACKGROUND: Identification of the ureter and transection of the bladder pillar are the hallmarks of radical vaginal hysterectomy. TECHNIQUE: First, the supraureteral part of the bladder pillar is transected laparoscopically. After identification of the ureter by the "click" maneuver, the infraureteral part of the bladder pillar is transected vaginally. Then, the rest of the supraureteral part of the bladder pillar is exposed by eversion of the uterine fundus and transected vaginally. EXPERIENCE: Between August 1994 and May 1997, 71 women were treated consecutively for cervical cancer stages IA2-IVB. Our new technique was performed in 16 women and compared with 55 patients in whom traditional techniques were used. Intraoperative and postoperative data were recorded prospectively. The duration of the vaginal phase of the operation was shortened significantly with our new technique compared with traditional techniques. There was no significant difference in intraoperative and postoperative injuries to the bladder or to the ureter for the various techniques. CONCLUSION: Our technique of identification of the ureter and dissection of the bladder pillar may prove a valid alternative to the traditional techniques, with statistically significant time gain.

Female↗