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C K Brown

Publications and source records attributed to C K Brown.

At least 37 records · Page 2Linked to original sources
PubMed1999

Full-time employees of U.S. local health departments, 1992-1993.

This article describes a study to assess the most recent data on full-time U.S. local health department (LHD) staff positions. The authors used data from the National Association of County and City Health Officials' 1992-1993 national survey of LHDs. The study concludes that nurses, environmental specialists, sanitarians, and administrators constitute the core of the public health workforce in smaller and mid-sized LHDs. Numerous vacancies in these core occupations signal a weakness in the front lines of public health and vulnerability in its ability to respond to urgent health threats. To address these problems, a renewed commitment to recruiting, retraining, and retaining the local public health worker is urgently needed.

Administrative Personnel↗
PubMed1998

A model of the quaternary structure of enolases, based on structural and evolutionary analysis of the octameric enolase from Bacillus subtilis.

Purified enolase from Bacillus subtilis has a native mass of approximately 370 kDa. Since B. subtilis enolase was found to have a subunit mass of 46.58 kDa, the quaternary structure of B. subtilis is octameric. The pl for B. subtilis enolase is 6.1, the pH optimum (pHo) for activity is 8.1-8.2, and the Km for 2-PGA is approximately 0.67 mM. Using the dimeric Calpha structure of yeast dimeric enolase as a guide, these dimers were arranged as a tetramer of dimers to simulate the electron microscopy image processing obtained for the octameric enolase purified from Thermotoga maritima. This arrangement allowed identification of helix J of one dimer (residues 86-96) and the loop between helix L and strand 1 (HL-S1 loop) of another dimer as possible subunit interaction regions. Alignment of available enolase amino acid sequences revealed that in 16 there are two tandem glycines at the C-terminal end of helix L and the HL-S1 loop is truncated by 4-6 residues relative to the yeast polypeptide, two structural features absent in enolases known to be dimers. From these arrangements and alignments it is proposed that the GG tandem at the C-terminal end of helix L and truncation of the HL-S1 loop may play a critical role in octamer formation of enolases. Interestingly, the sequence features associated with dimeric quaternary structure are found in three phylogenetically disparate groups, suggesting that the ancestral enolase was an octamer and that the dimeric structure has arisen independently multiple times through evolutionary history.

Amino Acid Sequence↗
PubMed1998

Assessing the impact of Medicaid managed care on TB activities in local health departments.

Three in-depth case studies were conducted to explore the impact of Medicaid managed care on local health department prevention activities. Tuberculosis (TB) was selected as a sentinel issue because TB includes both clinical treatment and population-based public health considerations (such as surveillance and contact tracing). Overall, study results indicated that there has been a minimal impact on TB prevention and control services, primarily because few TB patients are served by managed care. However, the sites offer many suggestions for areas to monitor, possible collaborative opportunities, and mechanisms to assure continued TB prevention and control.

Humans↗
PubMed1998

Augmented capillary leak during isolated hepatic perfusion (IHP) occurs via tumor necrosis factor-independent mechanisms.

Isolated organ perfusion of the liver or extremity with tumor necrosis factor (TNF) and melphalan results in regression of bulky tumors in the majority of patients. The efficacy of TNF in this setting is not known, although data suggest that it may exert antitumor effects primarily on tumor-associated neovasculature. We studied the effects of TNF on capillary leak in liver and tumor tissue during isolated hepatic perfusion (IHP) with melphalan. Twenty-seven patients with unresectable cancer confined to the liver underwent a 60-min hyperthermic IHP using 1.5 mg/kg melphalan alone (n = 7) or with 1.0 mg of TNF (n = 20). Complete vascular isolation was confirmed in all patients using an intraoperative leak monitoring I-131 radiolabeled albumin technique. Samples of tumor and liver were collected just prior to and immediately after IHP. There was no difference in I-131 radiolabeled cpm/g of tissue (cpm) in liver versus tumor at baseline (P2 = 0.44). After IHP, I-131 albumin cpm were higher in tumor versus liver (10,999 +/- 1,976 versus 3,821 +/- 780, respectively; P2 < 0.005). However, I-131 albumin cpm in tumor were not effected by TNF (11,636 +/- 2,518 with TNF versus 9,180 +/- 2,674 without TNF; P2 = 0.59). TNF did not affect melphalan concentrations in tumor (1,883 +/- 540 ng/g versus 1,854 +/- 861 ng/g without TNF; P2 = 0.9). Capillary leak, as reflected by diffusion of I-131 radiolabeled albumin into the interstitial space, is comparable in liver and tumor before IHP but is significantly higher in tumor after IHP. The increased diffusion in the capillary tumor bed must occur through TNF-independent mechanisms such as intrinsic features of tumor neovasculature, hyperthermia, or other unrecognized perfusion-related factors. These data indicate that TNF must continue to be critically evaluated in clinical trials before it is routinely used with melphalan in isolated organ perfusion.

Adult↗
PubMed1997

Intraarterial calcium stimulation and intraoperative ultrasonography in the localization and resection of insulinomas.

BACKGROUND: Standard imaging studies (computed tomography, magnetic resonance imaging, somatostatin receptor scintigraphy, ultrasonography, and angiography) correctly localize insulinomas in less than 50% of patients and provide no information about the feasibility of enucleation based on proximity of tumor to pancreatic duct. We reviewed our experience with intraarterial calcium stimulation (Ca-Stim) and intraoperative ultrasonography (IOUS) to localize and guide management of insulinomas. METHODS: Thirty-six patients (14 men, 22 women, median age 44 years) with insulinomas were treated between August 1989 and June 1996. Preoperative imaging studies were obtained. Patients underwent abdominal exploration with IOUS. Fourteen were evaluated by a surgeon blinded to preoperative imaging results. RESULTS: Tumors (4 to 50 mm) were resected by enucleation (67%) or partial pancreatectomy (33%); all were cured. Sensitivities of computed tomography, magnetic resonance imaging, somatostatin receptor scintigraphy, ultrasonography, angiography, and Ca-Stim in localizing insulinomas were 24%, 45%, 17%, 13%, 43%, and 94%, respectively. Tumors were identified by blinded surgical exploration with IOUS in 12 of 14 patients (86%). CONCLUSIONS: All insulinomas were identified before operation; however sensitivity of individual noninvasive tests was low (less than 50%). In contrast, Ca-Stim was correct in 94% of cases, thus allowing a focused pancreatic exploration and obviating use of blind distal pancreatectomy. IOUS can then be used to guide safe enucleation.

Adolescent↗
PubMed1996

The Foot Function Index for measuring rheumatoid arthritis pain: evaluating side-to-side reliability.

The Foot Function Index is a validated and reliable instrument for measuring foot pain, disability, and activity restriction in patients with rheumatoid arthritis. For the purposes of orthopaedic studies in which one foot serves as an internal control, we assessed the side-to-side reliability of the seven-question Foot Function Index pain subscale. Thirty patients with rheumatoid arthritis completed visual analog scale pain questionnaires for both feet on two occasions 8 days apart. Internal reliability of the scale was high, with Cronbach's alphas ranging from 0.94 to 0.96, suggesting good left versus right discriminatory abilities. Principal component factor analysis segregated the questions into two large clusters containing predominantly either left or right foot items. Intraclass correlation coefficients were examined for test-retest reliability (separated by side) and for side-to-side reliability (separated by the day of test). The resultant intraclass correlation coefficients were nearly equivalent, ranging from 0.79 to 0.89. Generalizability analysis yielded similar results. Intraclass correlation coefficients and generalizability analysis demonstrate that the majority of variation is best explained by the differences within subjects or between subjects rather than by test-retest or side-to-side differences. We recommend the Foot Function Index as a reliable measurement scale for use in orthopaedic interventional trials.

Adult↗
PubMed1996

Effects of dietary calcium and phosphorus on vitamin D metabolism and calcium absorption in hamster.

We studied the following responses to restriction of dietary calcium and phosphorus in the growing hamster: (i) serum concentrations of calcium, inorganic phosphorus, magnesium, and vitamin D metabolites; and (ii) calcium transport by ileum. Diets fed were normal calcium with normal or low phosphorus or low calcium with normal or low phosphorus. We found serum 1 alpha,25-dihydroxycalciferol (1,25-[OH]2D) concentration did not differ significantly among the diet groups. Calcium absorption, measured as serosal/mucosal calcium concentration ratio produced by everted ileal sac, was greater in the low calcium, normal phosphorous group than in all other groups. The other groups did not differ from one another in calcium absorption. Feeding the low calcium, normal phosphorus diet increased inorganic phosphorus and magnesium but decreased calcium concentration in serum in comparison with the three other diets. Both low phosphorus diets were without effect on serum calcium, but the low calcium, low phosphorus diet increased serum inorganic phosphorus and magnesium above that of the normal calcium, low phosphorus diet. Ileal calcium absorption in hamster (i) was independent of serum 1,25-(OH)2D concentration; (ii) increased in response to low dietary calcium if dietary phosphorus was normal; and (iii) was independent of dietary calcium, if dietary phosphorus was low. Despite increased calcium absorption, serum calcium was decreased in the low calcium-normal phosphorus group as compared with all other groups. Feeding low calcium diets increased serum inorganic phosphorus and magnesium as compared with feeding the corresponding normal calcium diets (i.e., independently of whether dietary phosphorus content was normal or low). These studies demonstrate that the interrelationships between calcium absorption and vitamin D and mineral metabolism in hamster differ from other mammals.

Absorption↗
PubMed1995

Survival of patients with localized prostate cancer treated with percutaneous transperineal placement of radioactive gold seeds: stages A2, B, and C.

Between 1984 and 1991, a total of 177 patients with adenocarcinoma of the prostate were treated with transcutaneous, transperineal radioactive gold seeds. Of these 177 patients, 20 were determined to have pelvic lymph node involvement and were excluded from this review. The remaining 157 patients received a median radioactivity dose of 164 mCi with a median follow-up of 48 months. Cancer-specific survival at 5 years was 100% for stage A2 and B1, 90% for stage B2, and 76% for stage C cancer. Covariates of grade, total radioactivity administered, age of the patient, and number of seeds implanted did not influence disease-free survival in a statistically significant manner. Significant complications were observed in two patients. The survival rates of patients treated with 198Au seed implantation for localized cancer are equivalent or better when compared to historical data of patients treated with 125I implantation, external beam radiotherapy, combination radioactive gold seed implantation and external irradiation, and radical prostatectomy. In addition, these comparable survival rates using interstitial 198Au seeds may be achieved with less morbidity.

Actuarial Analysis↗
PubMed1995

Discharge instructions: do illustrations help our patients understand them?

STUDY OBJECTIVE: To determine whether the addition of illustrations to discharge instructions improves patient comprehension. DESIGN: Randomized, blinded, prospective study. A blinded investigator asked a series of questions designed to test the participant's comprehension of the discharge instructions. There were 10 possible correct responses. SETTING: Emergency department of a rural Level I trauma center. PARTICIPANTS: Convenience sample of 101 patients discharged with the diagnosis of laceration. INTERVENTIONS: Patients were randomly assigned to receive discharge instructions with (n = 54) or without (n = 47) illustrations. RESULTS: The median number of correct responses was five. Patients with illustrations were 1.5 times more likely to choose five or more correct responses than those without illustrations (65% versus 43%; P = .033). The effect of illustrations varied by demographic group. Among nonwhites (n = 51), patients with illustrations were more than twice as likely to choose five or more correct responses (P = .032). Among patients with no more than a high school education (n = 71), patients with illustrations were 1.8 times more likely to choose five or more correct responses (P = .038). Among women (n = 48), patients with illustrations were 1.7 times more likely to chose five or more correct responses (P = .006). CONCLUSION: The addition of illustrations to discharge instructions for patients who have sustained lacerations improves patient comprehension. There is a large effect among patients who are nonwhite, female, or have no more than a high school education.

Audiovisual Aids↗
PubMed1995

Conference attendance: do we meet the new residency review committee requirements?

STUDY OBJECTIVES: To characterize the attendance at and presenters of conferences given to emergency medicine residents and to determine the ability of emergency medicine residents to attend conferences while working in the emergency department and on off-service rotations. DESIGN: Descriptive study of an anonymous mail survey. PARTICIPANTS: Residency directors of all approved emergency medicine residency programs in the United States. RESULTS: Seventy-six of 95 questionnaires (80%) were returned. We defined "high attendance" at emergency medicine conferences as a reported average of at least 75% attendance by emergency medicine resident physicians. Fifty percent of respondents reported high attendance. Conversely, 17% of programs reported poor attendance, which we defined as an average attendance by 50% or fewer emergency medicine resident physicians. Forty-eight percent of programs reported that emergency medicine faculty conducted more than 50% of the conferences, and 16% reported that the faculty conducted 25% or fewer conferences. Ninety-six percent of programs allowed residents to attend conferences during off-service rotations. Ninety-two percent of programs relieved residents of clinical responsibilities during scheduled shifts in the emergency department so that they might attend lectures. CONCLUSION: We found that a sizable proportion of programs may not have met the new Residency Review Committee requirements for lecture attendance at the time the guidelines were issued. The vast majority of programs met guidelines for relief of clinical duties, and a large proportion of programs exceeded the requirements for percentage of lectures given by emergency medicine faculty.

Emergency Medicine↗
PubMed1995

Subcuticular sutures and the rate of inflammation in noncontaminated wounds.

STUDY OBJECTIVE: To determine whether buried, absorbable, subcuticular sutures increase the degree of inflammation in noncontaminated wounds. DESIGN: Randomized, blinded, prospective trial. SETTING: Laboratory. PARTICIPANTS: Eleven Sprague-Dawley rats weighing 300 to 325 g. INTERVENTIONS: Four wounds were made on each rat. Two wounds on each were closed with three interrupted buried, absorbable, subcuticular sutures 6-0 polyglactin 910 and running 5-0 nylon skin sutures. The other two wounds were closed with running 5-0 nylon skin sutures alone. RESULTS: Fourteen days after the sutures were placed, the animals were killed, and histologic preparations were made from each wound. Each sample was scored on a scale of 0 to 3 for the presence of inflammatory infiltrates, fibroplasia and capillary proliferation, necrosis, exudates, giant cells, and edema. We determined a total wound score by adding the scores from each category. The mean total wound score was 4.46 +/- 2.92 for those closed with buried, absorbable, subcuticular sutures and 4.91 +/- 2.56 for those closed without buried, absorbable, subcuticular sutures. Using the Wilcoxon rank-sum test, we found no statistically significant difference in mean total wound score of wounds closed with and without buried, absorbable, subcuticular sutures (alpha = .01). The probability of detecting a twofold difference in total wound scores was 60% (beta = .40). CONCLUSION: Buried, absorbable, subcuticular sutures do not significantly increase the degree of inflammation in noncontaminated wounds.

Animals↗
PubMed1995

Physician compliance with advanced cardiac life support guidelines.

STUDY OBJECTIVE: To determine compliance with advanced cardiac life support (ACLS) guidelines among ACLS-certified and non-ACLS-certified physicians. DESIGN: Retrospective review of consecutive cardiac arrests between July 1989 and June 1990, including assessment of the resuscitation leaders' ACLS certification. SETTING AND PARTICIPANTS: All nontraumatic prehospital and hospital cardiac arrests in a rural university hospital. RESULTS: Two hundred seven arrests were studied for a total of 436 rhythms with a maximum of 4 rhythms per arrest. There were 78 resuscitations (36.3%) with return of spontaneous circulation. A total of 2,038 interventions were recorded for all rhythms, with 1,320 (64.8%) compliant with ACLS guidelines compared with 718 (35.2%) deviations. Synchronized cardioversion, calcium chloride and sodium bicarbonate were used with significantly higher noncompliance. Ventricular fibrillation had significantly higher mean rhythm deviation scores, whereas scores were significantly lower for sinus rhythm and stable bradycardia (P < .003). Resuscitations led by ACLS-certified and non-ACLS-certified physicians were compared for mean number of deviations per resuscitation attempt, and no differences were found. Resuscitations with return of spontaneous circulation were compared with unsuccessful resuscitations, and there was no difference between groups in controlled deviation scores. No differences could be found between ACLS-certified and non-ACLS-certified physicians for return of spontaneous circulation and survival-to-discharge rates. CONCLUSION: Despite biannual ACLS training of all medical residents and ICU nurses, noncompliance with ACLS guidelines was noted in 35.2% of treatments. We found no correlation between ACLS certification and ACLS guideline compliance.

Cardiopulmonary Resuscitation↗
PubMed1995

Preservation of peristaltic reflex in hypertrophied ileum of guinea pig.

Chronic obstruction of the guinea pig ileum leads to distension and muscular hypertrophy, but how this affects passive biomechanical and nerve-mediated contractions and clearance known as peristaltic reflex is unclear. Ileum of controls had a diameter of 3.0 +/- 1.1 mm and a circular muscle thickness of 37.2 +/- 11.2 microns; 4 wk after placement of a nonconstricting Gore-Tex band, the ileum was distended to 10.0 +/- 0.19 mm, and its muscle had hypertrophied to 195.0 +/- 61.2 microns. Hypertrophied segments exceeded controls in capacity (e.g., 5.1 +/- 1.1 vs. 1.1 +/0 0.2 ml at 6 cm), compliance, and hysteresis. Threshold volumes and pressures that triggered the reflex were 3.3 +/- 1.3 ml and 3.1 +/- 0.01 mmHg in hypertrophied vs. 0.7 +/- 0.2 ml and 1.5 +/- 0.2 mmHg in controls. The diameter increase that triggered the reflex was 1.4 +/- 0.1 mm in hypertrophied segments and 0.6 +/- 0.1 mm in controls. Hypertrophied segments generated fewer contractions of virtually double the amplitude and failed to generate a pressure differential between up- and downstream sites as controls did. Hypertrophied segments generated larger stroke volumes and cumulative clearance than controls. The ratio of antegrade to retrograde clearance was similar in hypertrophied and control segments. The length of the occluding segment in hypertrophied preparations exceeded that of controls. Control contractions indented the antimesenteric border and propagated antegrade from their site of origin; bizarre writhing movements of hypertrophied segments made their contractions difficult to monitor. Thus distension and muscular hypertrophy do not interfere with the ability of the chronically obstructed guinea pig ileum to generate a peristaltic reflex at least as readily and as powerful and as effective in clearing the lumen as controls.

Animals↗
PubMed1995

Bereavement care.

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Family Practice↗