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In this study, we demonstrate that manipulations of temperature and free calcium alter the morphology of the centrin-containing pericentriolar lattice of PtK2 cells. Immunofluorescence microscopy reveals that low-temperature incubation (4 degrees C) causes anti-centrin-labeled pericentrosomal spots to coalesce in the peripheral cytoplasm, and fuses small spots into larger spots near the cell center. At electron microscopic resolution, well-formed pericentriolar satellites appear around the centrioles in response to incubation at 4 degrees C. Elevated free calcium enhances these low-temperature-dependent effects. The data suggest that pericentrosomal spots correspond to one or more pericentriolar satellites, and that pericentriolar satellites and centrosomal matrix are interconvertable forms of the same material. Transient elevation of intracellular free calcium at 37 degrees C from a basal level of 3.7 x 10(-8) M to a peak level of 2.0 x 10(-7) M within 30 seconds with ionomycin results in a 35% increase in pericentrosomal spot number throughout the cytoplasm. The number of pericentrosomal spots is 50% larger 2 minutes after ionomycin addition; these spots are also nearer to the cell center as compared to 30 seconds after ionomycin addition. As intracellular free calcium returns to a basal level over 5 minutes, the number of spots and their cellular distribution resume a pretreatment value and pattern. We interpret these observations to indicate movement of pericentrosomal spots toward the cell center in response to the flux in intracellular free calcium. Alternatively, it is possible that no movement has occurred, but that the rise in free calcium has unmasked an epitope responsive to our anti-centrin antiserum. Regardless of the interpretation, we conclude that the pericentriolar lattice exhibits calcium-modulated behavior.

To investigate the suggestion that the incidence of polycythemia vera has increased in recent decades, we ascertained secular trends in the incidence of polycythemia vera in Olmsted County, Minnesota, over the 55-year period, 1935-1989. The inpatient and outpatient medical records of all potential cases of polycythemia vera in Olmsted County residents were reviewed and the diagnostic criteria of the Polycythemia Vera Study Group were applied. We found no indication of an increase in the age- and sex-adjusted incidence of polycythemia vera, which averaged 1.9 per 100,000 person-years (95% C.I., 1.4-2.5) over the study period. Incidence rates increased with age, and age-adjusted incidence rates were greater for men (2.8 per 100,000 person-years; 95% C.I., 1.8-3.9) than for women (1.3 per 100,000 person-years; 95% C.I., 0.7-1.9), with the highest incidence rate (23.5 per 100,000 person-years) among men aged 70-79 years. Survival was reduced in this inception cohort of 50 cases, compared to that expected for individuals of like age and sex (P < 0.0001); median survival following diagnosis was 7.2 years.

Our purpose was to determine the intratester and intertester reliability of measurements of both scapular and glenohumeral rotation during active arm elevation in the scapular plane with a new device, the scapulohumeral goniometer (SHG). Ten physical therapists, with 1 to 29 years of clinical experience, obtained repeated measurements on 45 subjects who were 27 to 82 years old. All subjects were tested in a uniform standing position with the handheld SHG, which was positioned over the subject's scapula and posterior shoulder according to operationally defined landmarks. For both scapular and glenohumeral rotation, 50% of the time the first and second measurements made on a patient by the same physical therapist differed by 3 degrees or more. Ten percent of the time, these measurements differed by 8 degrees or more. Measurements of active range of movement of scapular and glenohumeral rotation made by the same physical therapist during arm elevation in the scapular plane are clinically unacceptable when obtained with the current techniques for positioning the SHG. Clinical decisions based on results of active scapular and humeral motion in the scapular plane as measured on a patient by the same therapist with an SHG should be made with caution, because of the variability associated with this procedure.

Since 1989, 72 Telectronics 330-201 active fixation, polyurethane insulated ventricular leads (Accufix) have been implanted at the Mayo Clinic. There were four (5.6%) acute lead related complications (perforation, microdislodgment, and macrodislodgment), three of which led to early reoperation. Over a follow-up time of up to 2.7 years (median 9.4 months), there were six (8.3%) chronic lead related complications but no failures of lead material. Most of these complications developed during the first month, and half of them were transient, with documented improvement later. Two patients (2.8%) required reoperation for chronic complications. At follow-up examination of the pacing thresholds, usually performed about 3 months after implantation, 14.3% of the examined patients had high pacing thresholds necessitating high-output programming. The mechanisms and later evolution of this phenomenon should be further evaluated.

From 1976 to 1986, 106 patients with early glottic carcinoma were managed endoscopically at our institution. Twenty-four (23%) patients required retreatment of the larynx for local recurrences or new primary lesions after initial endoscopic management. The probability of remaining free of local recurrence 3 years after primary surgery was estimated to be 0.87 and, after 5 years, it was 0.81. Of the 24 patients who required re-treatment of their larynx, 10 did so beyond 3 years, indicating a new second primary. In 1 patient who required retreatment within 3 years, a new primary developed on the opposite cord. Therefore, true local recurrences developed in 13 patients (12.3%); 3 of these patients (2.8%) ultimately required laryngectomy and 3 are dead (2.8%) with disease.

Background: The long-term survival of 81 patients with T3 squamous cell carcinoma of the glottic larynx treated with laryngectomy alone is presented and pathologic predictors for cancer recurrence above the clavicles and cancer death are identified., Methods: Clinical records, operative notes, and pathologic slides were reviewed. The major end points were failure above the clavicles, cause-specific survival, and overall survival. All patients were followed until death or a minimum of 10.8 years., Results: The main pattern of treatment failure was within an undissected ipsilateral or contralateral neck. Subglottic extension and nodal metastases predicted failure above the clavicles and delayed metastasis within an undissected neck. The 5-year rate of control of disease above the clavicles, cause-specific survival, and overall survival were 74.1%, 73.7%, and 54.3%, respectively., Conclusions: Patients treated with laryngectomy for T3 glottic cancer who have pathologic evidence of subglottic extension or nodal metastasis are at higher risk for recurrence above the clavicles, particularly within an undissected neck.

Objective: To compare the prevalence of anemia among community and referral patients., Design: A Mayo Clinic laboratory database was searched for hemoglobin determinations between Jan. 1, 1985, and Dec. 31, 1989, in residents and nonresidents of Olmsted County, Minnesota, who were 20 years of age or older (a more restricted period within this interval was used for those 70 years of age or older)., Material and Methods: Using the World Health Organization criteria for anemia, we estimated the prevalence of anemia as of July 1, 1987, among Olmsted County residents 20 years of age or older (community patients) and compared this finding with the prevalence among non-Olmsted County patients of the same age registered at the Mayo Clinic during the same year (referral patients)., Results: The crude prevalence of anemia among Olmsted County men was less than that among male referral patients, but this difference was decreased by adjusting for the older mean age of referral patients (6.6% versus 7.0%; P = 0.01). Even after age-adjustment, the prevalence of anemia was greater among community women than among female referral patients (12.4% versus 8.2%; P < 0.001). Before age 55 years, the prevalence of anemia was lower among men than among women, but after that age, anemia became more frequent in men, reaching a 44.4% prevalence among community men 85 years of age or older. The overall prevalence rate was sensitive to the criteria used to define a low hemoglobin level, however., Conclusion: Clinicians should be aware of the high prevalence of anemia, especially among elderly community patients. This precaution should help minimize the overlooked diagnosis of anemia and the failure to identify and treat its underlying cause.

The purpose of this study was to examine the effects of age, sex, and hand preference on precise control of voluntary movement at the index finger metacarpophalangeal joint in able-bodied volunteers. An electrogoniometer was attached to this joint and connected to a computer. The computer screen displayed a sine wave target that each subject attempted to track with careful extension and flexion finger movements. Accuracy index scores were calculated for the extension phases, flexion phases, and the total sine wave. Each subject performed three tracking trials and the average for each of the above scores was computed. The results showed that younger subjects tracked significantly more accurately than older subjects and men tracked significantly more accurately than women. Also, the subjects tracking with the nonpreferred hand (15 right, 105 left) tracked significantly more accurately than those subjects tracking with the preferred hand (112 right, 8 left) in the flexion phases of the test. The data from these able-bodied subjects provide a base for comparison of patients' data, which may be helpful in the early recognition and monitoring of problems with precision in movement control.

Since 1989, 168 Telectronics model 330-801 active fixation, polyurethane insulated atrial leads (Accufix) have been implanted at the Mayo Clinic. There were four (2.4%) acute lead related complications, (i.e., perforation, microdislodgment, and pericarditis). Over a median follow-up time of 7.6 months (up to 2.7 years), there were 14 (8.3%) chronic complications, including 1 instance (0.6%) of definite lead failure. Most of these complications were early (within the first month) and transient. Four patients (2.4%) required reoperation for chronic complications. During follow-up, 23% of the examined patients had high pacing thresholds, most at about 3 months after implantation, necessitating high-output programming. The exact mechanism and natural history of this phenomenon should be further investigated.

Objective: The purpose of this study was to determine the recurrence rate and long-term survival of patients treated with open cervical procedures., Design: The study is a retrospective analysis of a cohort of patients who underwent an open laryngeal procedure between 1976 and 1986. The median follow-up was 6.6 years., Patients/participants: The sample was a consecutive series of 159 patients with early glottic carcinoma without impaired vocal cord mobility. Patients with a history of radiation therapy or surgical treatment elsewhere were excluded., Intervention: Surgical treatment in this group of 159 patients included 82 frontolateral partial vertical laryngectomies, 61 laryngofissures with cordectomy, 12 hemilaryngectomies, and four anterior commissure procedures., Outcome Measure: Estimates of survival time beyond the day of surgery, time to first recurrence (local, regional, and distant), and time to first local recurrence were obtained with the Kaplan-Meier product-limit method., Results: Eleven patients experienced recurrent laryngeal cancer. Ten patients underwent laryngectomy for recurrence. One patient underwent an anterior commissure procedure. Three of the 11 patients who underwent re-treatment of the larynx were ultimately salvaged. The probability of survival at 3 and 5 years was 91% and 84%, respectively. The probability of remaining free of local recurrence 3 and 5 years after surgery was 94% and 93%, respectively., Conclusion: In our experience, open laryngeal procedures continue to be excellent treatment for select cases of early glottic carcinoma. They are versatile and efficacious for managing the wide spectrum of larger T1 glottic carcinomas.

A retrospective review was performed of 199 consecutive patients who were evaluated at this institution between 1976 and 1990 because of a newly diagnosed bulbar urethral stricture. Mean patient age at diagnosis was 64 years (range 10 to 96) and most patients presented with obstructive symptoms. The stricture etiology was primarily iatrogenic (47%), secondary to a transurethral procedure. The strictures were usually short (less than 2 cm., 96%), single (99%) and located in the proximal bulb (57%). Of the 151 patients receiving treatment at the time of initial diagnosis 101 (67%) underwent urethral dilation, 39 (26%) were managed with direct vision internal urethrotomy and in 11 (7%) a cystotomy tube was placed. With a median followup of 3.5 years (range 0 to 16), there was an estimated retreatment rate of 2.4 treatments per 10 person-years. The probability of not requiring retreatment within 3 years was 65 +/- 5% for urethral dilation and 68 +/- 8% for direct vision internal urethrotomy. When compared to urethral dilation, direct vision internal urethrotomy resulted in a higher incidence of postprocedure cystitis (5% versus 3%), epididymitis (5% versus 3%) and penile hemorrhage (8% versus 2%). These findings indicate that both conservative therapies were equally efficacious as an initial treatment of bulbar urethral stricture. However, direct vision internal urethrotomy did have a slightly higher complication rate. No specific patient or stricture characteristics could be identified that were reliable for predicting therapeutic outcome.

With the rapidly spreading enthusiasm for early detection of prostate cancer and the increasing use of serum PSA to evaluate the gland, more cancers that are not palpable on digital rectal examination are being identified. These tumors have pathologic characteristics that are very similar to those of clinically localized, palpable prostate cancers identified on digital rectal examination. Thus, the tumors detected on the basis of an elevated serum PSA value should not be disregarded as insignificant. In fact, these tumors should be given the same therapeutic consideration as the clinically localized, palpable cancers. In the TNM staging system, "PSA-detected" cancers can be classified as stage T1c, and in the Whitmore-Jewett staging system, they can be referred to as stage B0. Long-term follow-up of these prostate cancers will be necessary to establish the prognosis.

A statistical model for predicting a woman's lifetime risk of hip fracture using her bone mineral density at menopause has been proposed by Black et al. (1992b). We made an additional assumption concerning the correlation of bone mineral density between any two ages among postmenopausal women and applied the modified model to baseline ages between 50 and 85 years and any bone mineral density level likely to be observed in the population. The results are displayed in a form more convenient for application of this model in the clinical setting.

We examined intratester and intertester reliability for goniometric measurements of ankle dorsiflexion (ADF) and ankle plantar flexion (APF) active range of motion (AROM). Parallel-forms intratester reliability for ankle AROM measurements obtained by the universal goniometer (UG) and by visual estimation (VE) and intertester reliability for VE of ADF and APF were examined. Repeated measurements were obtained on 38 patients with orthopedic problems by 10 physical therapists in a clinical setting. For intratester reliability of measurements obtained with UG, intraclass correlation coefficients (ICC) for all physical therapists were 0.64 to 0.92 (median, 0.825) for ADF and 0.47 to 0.96 (median, 0.865) for APF. Intertester reliability was quantified with use of ICC. ICCs for measurements obtained by UG were 0.28 for ADF and 0.25 for APF; ICC of VE for ADF was 0.34 and was 0.48 for APF. ICC for parallel-forms intratester reliability obtained with UG and VE ranged from 0 to 0.94 (median, 0.58) for ADF and 0 to 0.86 (median, 0.625) for APF. Thus, a physical therapist should use a goniometer when making repeated measurements of ankle joint AROM. Considerable inconsistency exists when two or more physical therapists make repeated goniometric and visual measurements of ankle motion on the same subject. Physical therapists may erroneously conclude that a patient's AROM has changed because of treatment when the change could be attributed to a lack of intertester reliability.

A case-control study was undertaken to assess whether a significant association exists between the presence of a neoplasm or malignancy and the presence of a cardiac myxoma. We identified 13 patients seen at our institution between 1935 and 1990 whose autopsies revealed a cardiac myxoma that was undetected during the patient's lifetime. For each patient four control subjects were selected among the autopsied patients who had never had a cardiac myxoma; these were matched for age at death, gender, and year of autopsy. The institutional medical records and autopsy reports revealed that 46% of the patients and 65% of their controls had a neoplasm diagnosed prior to or at autopsy. The estimated odds ratio was 0.34 (95% confidence interval, 0.05 to 1.84). There was insufficient evidence to conclude that an association exists between the presence of a neoplasm and the presence of a cardiac myxoma (P = .2722).

This retrospective study analyzed the outcome of lung cancer patients who were treated with either 4-MV or 10-MV photons. From October 1979 through December 1982, 126 patients with locally advanced, unresectable or medically inoperable, nonmetastatic non-small cell lung cancer were treated in a prospective trial in which they were randomly assigned to one of three chemotherapy combinations and thoracic radiotherapy. The patients were stratified by cell type, extent of operation, age, sex, and status of supraclavicular lymph nodes. All patients were followed until death or for a minimum of 4.8 years. Of the 102 evaluable patients, 98 were treated with either 4-MV or 10-MV photons (49 patients in each group). Outcomes examined included best primary tumor response, time to first local (in-field) recurrence, disease-free survival, and overall survival. No significant differences were detected between the patients treated with 4-MV or 10-MV photons for several important prognostic and treatment factors or for any of the study outcomes, including first local (in-field) recurrence, disease-free survival, and overall survival. For the group of 98 patients treated with either 4-MV or 10-MV photons, the estimated 2-year freedom from first local (in-field) recurrence was 47.7%. The estimated 2-year disease-free and overall survivals were 21.6% and 28.6%, respectively.

From January 1980 through December 1988, 8,219 thyroid smears were obtained by fine-needle aspiration (FNA) biopsy from patients at the Mayo Clinic, of which 918 (11%) were classified as "suspicious" cytologic findings. We analyzed the outcome in 208 patients with such findings who did not undergo immediate surgical treatment at the Mayo Clinic; follow-up data on thyroid status were available for 187 patients. Of 99 patients who underwent late surgical treatment (more than 30 days after FNA biopsy) and for whom tissue was available for diagnosis, thyroid malignant disease was found in 29. No clinical, scintigraphic, or ultrasonographic characteristics predicted the presence of a malignant lesion. On repeated FNA biopsy in 41 patients, findings were suspicious for a malignant lesion in 19 and benign in 22. Surgical excision was performed in 13 of the 41 patients. For 11 patients with suspicious cytologic findings on two FNA biopsies, malignant disease was confirmed in 5 and benign disease in 6. Two patients had benign histopathologic findings after cytologic results were benign on a second FNA biopsy. Follow-up data for the 208 patients revealed that 86 were alive with no evidence of thyroid disease, 76 were alive with some evidence of thyroid disease, 23 had died of nonthyroid illnesses, 2 had died of a thyroid malignant lesion, and 6 had died without undergoing surgical treatment (thyroid status unknown at the time of death); follow-up information was unavailable in 15 patients. The median duration of follow-up for those alive was 4.9 years.(ABSTRACT TRUNCATED AT 250 WORDS)

We studied 22 patients with clinical stage B2 (T2c) or C (T3) prostate cancer who underwent androgen deprivation therapy before radical prostatectomy as part of a downstaging protocol (group 1). The concentration of serum prostate specific antigen (PSA) was determined before and at the conclusion of androgen deprivation therapy, just before the operation. For each group 1 patient a match patient who had not received preoperative endocrine therapy (group 2) was chosen. The age of the group 2 patients was similar to that of the group 1 patients. The clinical stage of disease and pretreatment tumor grade in group 2 were identical to the stage and grade in group 1, and the serum PSA value in group 2 was similar to that of group 1 before initiation of androgen deprivation therapy. In group 1 the median serum PSA concentration was 14.8 ng./ml. (range 3.1 to 99) before endocrine therapy and 0.2 ng./ml. (range 0.1 to 3.4) after hormonal treatment. Group 2 had a median level of 13.3 ng./ml. (range 3.4 to 100). The median decrease in the serum PSA concentration for group 1 as a result of androgen deprivation therapy was 98.5%. The radical prostatectomy specimens from these 2 groups of similar patients had no difference with regard to maximal tumor dimension, pathological stage and deoxyribonucleic acid ploidy status. These findings indicate that serum PSA becomes an unreliable indicator of disease status after initiating preoperative androgen deprivation therapy and that preoperative androgen deprivation therapy has little or no benefit for decreasing the extent of tumor or pathological stage. The concept of downstaging is misleading and must be examined in a randomized clinical trial.

Select early glottic carcinomas in patients with normal vocal cord mobility can be successfully treated with cordectomy, performed either endoscopically or by means of an open operation (laryngofissure-cordectomy). From 1976 to 1986, 95 patients underwent cordectomy at our institution. There were 88 men and 7 women, with an age range at the time of surgery of 27 to 84 years. A laryngofissure was used to perform a cordectomy in 61 patients and an endoscopic approach was used in 34. The median number of days in the hospital for the endoscopic group was 2, and for the laryngofissure group it was 6. The Kaplan-Meier product-limit method showed the probability of no recurrence in the first 3 years after an endoscopic cordectomy was 0.9099, and in the laryngofissure-cordectomy group it was 0.9502. To date, there have been four recurrences (11.8%) in the endoscopic group and three (4.9%) in the laryngofissure group. Only one patient with recurrent tumor is known to have died of the cancer. Laryngectomy was necessary for ultimate control in three patients. The Kaplan-Meier survival curve for the 95 patients was the same as that for a sex- and age-matched control group. Cordectomy is an effective treatment option that results in minimal morbidity for select early glottic carcinomas.

Background: Because of controversy about the correct treatment of toxic solitary thyroid nodules, we reviewed our experience., Methods: We retrospectively studied 32 patients (24 women and 8 men) with solitary toxic thyroid nodules who were treated at our institution (1970 to 1985)., Results: Median values were as follows: age of patients at initial treatment, 67.6 years (range, 18.9 to 86.2 years); follow-up, 3.8 years; largest diameter of nodules, 3.3 cm (range, 1.5 to 6 cm); and 131I uptake at 24 hours, 31% (range, 7% to 54%). Nine patients had surgical treatment: subtotal thyroid lobectomy in six patients and subtotal thyroidectomy in three patients. Hypothyroidism developed in two of these nine patients (22%) 9 months after operation. No surgical complications occurred. No surgically treated patient had nodule recurrence or required re-treatment. Twenty-three patients were treated with radioactive iodine (median dose, 29.1 mCi; range, 19.7 to 100 mCi). Two of them were re-treated: one patient underwent thyroid lobectomy because of concern about the nodule, and one patient was re-treated with radioactive iodine because of persistent toxicity. Hypothyroidism was detected in eight of the 23 patients (35%) treated with radioactive iodine after treatment. Of the 16 patients treated with radioactive iodine with at least 1 year follow-up and no re-treatment, nine (56.3%) have had complete regression of the nodule., Conclusions: Surgical excision of solitary toxic thyroid nodules would appear to be the treatment of choice.

The purposes of this study were (1) to determine normal values for cervical active range of motion (AROM) obtained with a "cervical-range-of-motion" (CROM) instrument on healthy subjects whose ages spanned 9 decades, (2) to determine whether age and gender affect six cervical AROMs, and (3) to examine the intratester and intertester reliability of measurements obtained. Measurements were made on 337 subjects (171 females and 166 males) whose ages ranged from 11 to 97 years. Measurements were taken by five physical therapists with 7 to 30 years of clinical and teaching experience. Among male and female subjects of the same age, females had a greater AROM than did males for all AROMs except neck flexion. Among both males and females, each of the six cervical AROMs decreased significantly with age. From two pilot studies separate from the acquisition of the normal database, we determined our intratester and intertester reliabilities for making neck AROM measurements with the CROM instrument. We concluded that AROM measurements on the cervical spine with the CROM instrument demonstrated good intratester and intertester reliability, because the intraclass correlation coefficients were generally greater than .80.

A multicenter study was undertaken to determine the failure rate of a specific polyurethane bipolar tined pacing lead, the Medtronic 4012 pacing lead. Six centers in the United States and Canada implanted 1,190 Medtronic 4012 pacing leads. The study was designed to determine the probability and clinical manifestations of lead failure. Only failures compatible with an insulation problem were included. The probability of a 4012 lead failure by Kaplan-Meier analysis was 20.9% at 6 years after implantation. Failures were manifested as sensing abnormalities, failure to capture, early battery depletion, and significant decrease in measured impedance compared with the previous impedance measurements. Of the 95 definite lead failures, 16 (16.8%) were associated with symptoms similar to those experienced before pacemaker placement. The observed failure rate is unacceptable, and strong consideration should be given to replacing the 4012 pacing lead in pacemaker-dependent patients and closely monitoring nondependent patients.