Evaluation of conditioning time and temperature on gelatinized starch and vitamin retention in a pelleted swine diet.

Two key feed processing parameters, conditioning temperature and time, were altered to determine their effects on concentration of gelatinized starch and vitamin retention in a pelleted finishing swine diet. Diet formulation (corn­soybean meal based with 30% distillers dried grains with solubles) was held constant. Treatments were arranged in a 2 × 3 factorial design plus a control with 2 conditioning temperatures (77 vs. 88°C) and 3 conditioner retention times (15, 30, and 60 s). In addition, a mash diet not subjected to conditioning served as a control for a total of 7 treatments. Samples were collected after conditioning but before pelleting (hot mash), after pelleting but before cooling (hot pellet), and after pelleting and cooling (cold pellet) and analyzed for percentage total starch, percentage gelatinized starch, and riboflavin, niacin, and vitamin D3 concentrations. Total percentage starch was increased by greater conditioning temperature (P = 0.041) but not time (P > 0.10), whereas higher temperature and longer time both increased (P < 0.05) percentage gelatinized starch, with increasing time resulting in a linear increase in percentage starch gelatinization (P = 0.013). The interaction between conditioning temperature and time increased percentage gelatinized starch (P = 0.003) but not percentage total starch (P > 0.10). Sample location also affected both percentage total starch and gelatinized starch (P < 0.05), with the greatest increase in percentage gelatinized starch occurring between hot mash and hot pellet samples. As expected, the pelleting process increased percentage gelatinized starch (P = 0.035; 7.3 vs. 11.7% gelatinized starch for hot mash vs. hot pellet samples, respectively), but there was no difference in total starch concentrations (P > 0.10). Finally, neither conditioning temperature nor time affected riboflavin, niacin, or vitamin D3 concentrations (P > 0.10). In summary, both increasing conditioningtemperature and time effect percentage gelatinized starch, but not to the extent of forcing the diet through a pelleting die.

Effects of pelleting conditioner retention time on nursery pig growth performance.

A total of 180 nursery pigs (PIC 327 × 1050; initially 12.6 kg) were used in an 18-d study to determine the effects of pellet mill conditioning parameters and feed form on pig performance. All diets were similar, and different feed processing parameters were used to create experimental treatments. Factors considered were conditioning time (15, 30, or 60 s) and feed form (mash or pelleted). To remove the confounding factor of feed form, pelleted samples were reground to a similar particle size as the mash diet. Treatments included: 1) mash diet without thermal processing (negative control), 2) pelleted diet conditioned for 30 s (positive control), 3) pelleted diet conditioned for 15 s and reground, 4) pelleted diet conditioned for 30 s and reground, and 5) pelleted diet conditioned for 60 s and reground. Pigs were weaned and fed a common acclimation diet for 21 d before the start of the experiment. Growth and feed disappearance were then measured for 18 d. All diets had similar levels of percentage total starch, but thermally processed diets had a 1.67 to 1.87-fold increase in percentage gelatinized starch compared to the mash diet. Average daily gain and G:F did not differ between treatments overall, but pigs fed the positive control pelleted diet had decreased ADFI ( < 0.05) compared to pigs fed all other diets. Preplanned contrasts revealed that pigs fed mash diets tended to have greater ADG ( < 0.10) compared to those fed pelleted and reground diets. This suggests that processing may have had a negative influence on feed utilization, which is further supported by the finding that pigs fed mash diets tended to have greater ADG ( < 0.10) compared to those fed diets that were thermally processed, regardless of regrinding. Considering these results, it was not surprising that pigs fed mash diets had greater ADG and ADFI ( < 0.05) than those fed pelleted diets. When directly comparing diets conditioned at 60 rpm, fed either as whole pellets or reground to mash consistency, pigs fed pelleted diets had improved G:F ( < 0.05) due to lower ADFI ( < 0.05) but similar ADG. The expected improvement in G:F from pelleting (6.8%) was observed but lost when diets were reground to near original mash particle size. This may indicate that diet form from the actual pelleting process impacts G:F more than conditioner retention time.

Characterization of Lyme meningitis and comparison with viral meningitis in children.

OBJECTIVES: The objectives of this study were to characterize Lyme meningitis (LM) in the pediatric population; to compare LM with viral meningitis (VM) with respect to epidemiology, history and physical examination, and laboratory data; and to provide means of early distinction of Lyme neuroborreliosis from other forms of aseptic meningitis. METHODS: This retrospective analysis involved children admitted to Alfred I. duPont Hospital for Children between 1990 and 1996 whose discharge diagnoses indicated viral or aseptic meningitis or Lyme disease. LM was defined as the presence of cerebrospinal fluid (CSF) pleocytosis with positive Lyme serology and/or erythema migrans. Patients were considered to have VM if they exhibited CSF pleocytosis and had a positive viral culture. Demographic, clinical, and laboratory data were collected for each patient, and patients with LM were compared with age-matched patients with VM. RESULTS: Of 179 patient records, 12 patients with LM and 10 patients with VM (all, >2 years old) were identified by using the above criteria. In comparing LM patients with VM patients, we noted no differences among demographic variables. Children with LM had significantly lower temperatures at the time of presentation. The presence of headache, neck pain, and malaise was similar for the two groups, but the duration of these symptoms was significantly longer among LM patients. Five children with LM had cranial neuropathies. All but 1 LM patient exhibited either papilledema, erythema migrans, or cranial neuropathy. These three findings were absent in the VM group. On CSF analysis, LM patients had fewer white blood cells (mean, 80/mm3 versus 301/mm3) and a significantly greater percentage of mononuclear cells than the VM patients. CONCLUSIONS: In this study, in a Lyme-endemic area, LM was about as common as VM in older children who were hospitalized with aseptic meningitis. Attention to pertinent epidemiologic and historical data, along with physical and CSF findings, allows early differentiation of LM from VM.

Pancreatitis in human immunodeficiency virus-infected children receiving dideoxyinosine.

To define predictive or contributory risk factors for pancreatitis in human immunodeficiency virus-infected children receiving dideoxyinosine (ddI), the authors evaluated 95 children, 3 months to 18 years of age, who had received ddI at 60 to 540 mg/m2 per day for a mean of 56 weeks. Pancreatitis developed in 7 patients (7%) but resolved in all upon withdrawal of ddI. Neither age, sex, nor CD4 count at study entry was predictive of pancreatitis, but pancreatitis appeared more likely to develop in hemophiliacs than in other patients (4 of 23 vs 3 of 72). Pancreatitis developed only in patients who received ddI at the highest dose levels (7 of 60 patients who received ddI at a dose > or = 360 mg/m2 per day vs 0 of 35 patients who received < or = 270 mg/m2 per day). Patients in whom pancreatitis developed had received a higher mean daily dose of ddI than patients with normal amylase and lipase levels throughout the study (348 mg/m2 vs 282 mg/m2), but no relationship with the cumulative dose or the duration of ddI therapy was observed. Although a statistically significant relationship between ddI plasma concentration (area under the curve) and pancreatitis was not conclusively demonstrated, as the number of patients in whom pancreatitis actually developed was small, such a relationship may have been obscured.(ABSTRACT TRUNCATED AT 250 WORDS)

Zidovudine and didanosine combination therapy in children with human immunodeficiency virus infection.

OBJECTIVE: Zidovudine and didanosine are both beneficial for the treatment of human immunodeficiency virus (HIV) infection in children. Because disease progression and toxicity often limit their long-term use as single agents, new approaches to using nucleoside analogues are necessary to improve current antiretroviral therapy. DESIGN: We conducted a phase I-II study to evaluate the tolerance, pharmacokinetics, and antiviral activity of the combination of zidovudine and didanosine in children with HIV infection. Sixty-eight children who were either previously untreated or who had manifested hematologic toxicity on full-dose zidovudine were enrolled. Eight dose combinations were studied in the previously untreated children, with doses of zidovudine ranging from 90 to 180 mg/m2 every 6 hours and doses of didanosine ranging from 90 to 180 mg/m2 every 12 hours. RESULTS: Fifty-four previously untreated HIV-infected children were enrolled in this part of the study, of whom 49 remained in the study for a minimum of 24 weeks. For children with previous zidovudine-related hematologic toxicity, three dose levels with zidovudine at 60 mg/m2 every 6 hours orally and didanosine ranging from 90 to 180 mg/m2 every 12 hours orally were used. A total of 14 children were enrolled in this part of the study, and 12 remained on therapy for at least 24 weeks. No evidence of new or enhanced toxicity was observed in either group. After 24 weeks, the median CD4 cell count for all patients increased from 331 to 556 cells/mm3 (P = .01). For the previously untreated group, the median increase in CD4 counts was from 386 to 726 cells/mm3 (P = .003). The median p24 antigen concentration (in those with a detectable level at baseline) decreased from 95 to < 31 pg/mL (p < .001). The geometric mean titer of HIV in plasma decreased from 83.1 to 2.7 tissue culture infectious doses/mL (P = .001). CONCLUSIONS: The combination of zidovudine and didanosine was well-tolerated at doses as high as those used in single agent therapy. Potent in vivo antiviral activity was observed. Combination therapy with nucleoside analogues may be an important approach to optimizing the use of these agents in the treatment of HIV infection.

Clinical and pharmacokinetic evaluation of long-term therapy with didanosine in children with HIV infection.

BACKGROUND: Didanosine has demonstrated promising antiviral activity and a tolerable toxicity profile in short term studies. We describe a cohort of HIV-infected children who were treated for a prolonged period of time with didanosine. METHODS: Children (6 months to 18 years of age) with symptomatic HIV infection or an absolute CD4 count < 0.5 x 10(9) cells/L, received oral didanosine at doses between 20 mg/m2 to 180 mg/m2 every 8 hours. Clinical, immunological, and virological parameters were assessed at least every 2 months. The pharmacokinetics of didanosine were evaluated in 85 patients. RESULTS: Previously untreated children (n = 51) and children who had received prior antiretroviral therapy (n = 52) were enrolled in the study (median time on study 22.6 months; range 2 to 48). The long-term administration of didanosine was well tolerated and no new toxicities were observed. The absolute CD4 count increased by > or = .05 x 10(9) cells/L in 28 of 87 (32%) of patients after 6 months of therapy. Responses were also sustained in 41% of these children after 3 years of therapy. Children entering the study with a CD4 count > 0.1 x 10(9) cells/L (n = 51) had a marked survival advantage (P = .00002) with an estimated survival probability after 3 years of 80% compared to 39% for children with lower CD4 counts. Although the area under the curve of didanosine increased proportionally with the dose, there was considerable interpatient variability at each dose level. There was no apparent relationship between surrogate markers of clinical outcome and plasma drug concentration. CONCLUSIONS: Didanosine was well tolerated with chronic administration, and toxicities were uncommon and usually reversible. In 41% of patients, the CD4 count increased and was maintained at the higher level even after years of treatment.

Pseudomonas infections in children with human immunodeficiency virus infection.

Thirteen bacteremias and 25 nonbacteremic infections caused by Pseudomonas spp. occurred in 22 of 236 children with human immunodeficiency virus infection with a rate of infection of 0.098 (bacteremia, 0.030) per patient year. Four patients were neutropenic (less than 500/microliters). Central venous catheter (CVC)-related infections were most frequent (n = 20) followed by otitis externa (n = 6) and pneumonia (n = 5). Pseudomonas aeruginosa was the most common isolate and caused both CVC-related and CVC-unrelated infections, whereas other Pseudomonas spp. and Xanthomonas maltophilia were almost exclusively associated with CVC-related infections. The children who received appropriate therapy had a favorable outcome. In 7 CVC-related infections (35%) the catheter was removed. Pseudomonas spp. are of increasing importance in human immunodeficiency virus-infected children causing significant morbidity and increased hospitalization. These infections may be life-threatening if appropriate therapy is not vigorously initiated.

Role of tissue diagnosis in pulmonary involvement in pediatric human immunodeficiency virus infection.

BACKGROUND: Pulmonary complications occur commonly during HIV infection. The aim of this study was to evaluate the clinical value of lung tissue examination in the diagnosis and treatment of pulmonary disorders in children with HIV infection. METHODS: The medical records of 347 children enrolled between January, 1990, and April, 1994, into various antiretroviral therapy protocols were reviewed to identify patients who underwent a lung biopsy. RESULTS: Fourteen patients underwent diagnostic lung biopsies on 16 separate occasions. The most common radiologic findings were nodular infiltrates which were localized in 7 patients and diffuse in 6. Eight patients presented with fever and progressive respiratory distress unresponsive to empiric therapy, whereas the rest had progressive nodular infiltrates. The pathologic diagnoses included opportunistic infection in 7 patients, lymphocytic interstitial pneumonitis in 5, non-Hodgkin's lymphoma in 3 and interstitial fibrosis in 1. The biopsy led to a major change in the treatment of 7 patients which resulted in a significant improvement of the pulmonary process in all of them. In an additional patient the excisional biopsy proved curative. CONCLUSIONS: When patients are selected appropriately, lung biopsy might have a significant impact on therapy and outcome in HIV-infected children with pulmonary infiltrates.

Cryptococcosis in human immunodeficiency virus-infected children.

BACKGROUND: Cryptococcosis is a common opportunistic infection in adults with AIDS. Few cases of cryptococcosis complicating pediatric AIDS have been reported. To our knowledge there are no studies that describe the epidemiology, clinical manifestations and outcome of cryptococcosis in a large population of HIV-infected children. METHODS: We identified the cases of cryptococcosis through a retrospective review of the hospital records of the 473 HIV-infected children prospectively monitored in the Pediatric Branch of the National Cancer Institute during the 8 years from 1987 to 1995. RESULTS: Four (0.85%) patients developed cryptococcosis during the study period. All patients had profound depression of the absolute CD4 counts, a history of previous opportunistic infections, and onset of cryptococcosis in the second decade of life. Cryptococcosis developed as a disseminated infection or a localized process of the lungs. Intermittent fever was the most common presenting manifestation. Serum cryptococcal antigen was positive in all patients and gradually declined after the institution of the antifungal therapy. All patients were treated with amphotericin B with or without flucytosine as initial therapy. Suppressive therapy consisted of fluconazole with or without flucytosine. There were no deaths due to Cryptococcus neoformans. CONCLUSIONS: Cryptococcosis is an infrequent yet treatable opportunistic infection of advanced pediatric AIDS that may present with subtle manifestations and warrants careful consideration in the evaluation of febrile HIV-infected children.

Bone resorption levels by age and menopausal status in 5,157 women.

OBJECTIVE: The purpose of this study was to describe bone resorption activity using a biochemical marker according to the categories of age, menopausal status, and selected drug/supplement use in middle-aged and elderly community-based women. DESIGN: This was a cross-sectional study that assessed urinary cross-linked N-telopeptide of type I collagen (NTx) and used self-report data to group women as premenopausal (Pre), perimenopausal (Peri), postmenopausal without hormone replacement therapy (Post), and postmenopausal with hormone replacement therapy (HRT). RESULTS: Mean NTx values were found to be significantly different by group and controlling for age (p = 0.001), with post hoc tests showing all pairwise group comparisons as significantly different (p = 0.001), except that the Pre and HRT groups were not significantly different. Both the Peri and the Post NTx levels were significantly higher than the Pre and the HRT groups'. NTx values in the Peri group varied with age-the youngest Peri women were similar to Pre women, and the oldest Peri women were similar to Post women. Significantly lower NTx levels were found only in the Post (p = 0.009) and HRT (p < 0.001) groups using diuretics compared with nonuse and only in the HRT group using calcium supplements compared with nonuse (p = 0.006). No differences by thyroid use were found. With a biochemical marker, the results showed that bone resorption activity differences could be demarcated in women according to age, estimated menopausal stage, and selected drug/supplement use. CONCLUSIONS: These results support the usefulness of NTx assessment for indicating bone resorption activity and therefore the potential for osteoporosis or for monitoring the efficacy of antiresorptive therapies.

Adaptation of bone and tendon to prolonged hindlimb suspension in rats.

The rat hindlimb suspension model was used to ascertain the importance of ground reaction forces in maintaining bone and tendon homeostasis. Young female Sprague-Dawley rats were randomly assigned to either a suspended or a nonsuspended group. After 28 days, femur bones and patellar tendons were obtained for morphological and biochemical analyses. Prolonged suspension induced a significant change in the geometric configuration of the femur middiaphysis by increasing the minimum diameter (12%) without any significant alterations in cortical area, density, mineral, and collagen concentrations. Femur wet weight, length, DNA, and uronic acid concentrations of suspended animals were not significantly different from bones of nonsuspended rats. However, the collagen and proteoglycan concentrations in patellar tendons of suspended rats were 28% lower than the concentrations of matrix proteins in tissues obtained from nonsuspended animals. These data suggest that elimination of ground reaction forces induces alterations in tendon composition and femur diaphyseal shape by changing regional rates in bone remodeling and localized tendon strain. Therefore it appears that ground reaction forces are an important factor in the maintenance of cortical bone and patellar tendon homeostasis during weight-bearing conditions.

Congenital syphilis. Serologic diagnosis in the young infant.

The diagnosis of congenital syphilis in the newborn or young infant must incorporate epidemiologic, clinical, and serologic evidence of infection. Anti-treponemal IgM assays such as the 19S-IgM-FTA-ABS, which can be performed at the CDC at the request of state health departments, and the IgM ELISA being developed by Ortho Diagnostics represent the most available of the new assays. Discrimination of CNS involvement by T. pallidum by new methods continues to be difficult in the absence of a "gold standard" for comparison; thus, the current recommendation is to treat all infected infants with a regimen adequate to eradicate neurosyphilis. Although tremendous progress has been made in recent years in new serologic techniques applicable to congenital syphilis, none have proved reliable enough yet to be widely used by physicians evaluating infants at risk. In conclusion, there is still no single serologic assay that will reliably diagnose congenital syphilis in the young infant and the weight of therapeutic decisions still rests on the physician's ability to synthesize epidemiological, clinical, and laboratory data.

Pulsatile release patterns of luteinizing hormone and progesterone in relation to symptom onset in women with premenstrual syndrome.

OBJECTIVE: To explore the pulsatile-release characteristics of LH and P in women with premenstrual syndrome (PMS) compared with age-matched phase-matched controls. DESIGN: Prospective, repeated measures, two-group study. SETTING: Human volunteers in an academic research environment. PARTICIPANTS: Six women with rigorously defined prospectively determined PMS; six age-matched phase-matched controls. MAIN OUTCOME MEASURES: Frequency, amplitude, concentration, and coincident pulsatile release characteristics of LH and P at three symptom-related points of the luteal phase. RESULTS: No significant between-group differences in frequency, amplitude, or concentration were found. In pooled data, significant coincident pulsing between LH and P was demonstrated. The length of time between LH and P pulses systematically increased across the luteal phase, a finding not previously reported. In the PMS group only, significant coincident pulsing occurred at an unexpected zero time lag on the symptom-onset sampling day. CONCLUSION: A progressively increasing coupling interval may reflect the gradual decline of the corpus luteum. Presence of a zero time lag between LH and P at symptom onset in women with PMS may indicate an aberrance in corpus luteum response to LH stimulation.

Control of geohelminths by delivery of targeted chemotherapy through schools.

This study describes the age-targeted chemotherapeutic control of geohelminthiasis in the total population (n = 11,500) of the island of Montserrat, West Indies. The intervention programme involved the treatment with single dose albendazole of all children aged 2-15 years (approximately 2500) in 4 sequential cycles at intervals of 4 months. Infection status was monitored by an initial coprological survey of an age-stratified sample (11.5%) of the population, and by surveys of smaller samples (4-5%) after 2 and 4 cycles of treatment (7 and 15 months respectively). The programme delivered treatment to greater than 90% of the target population in each cycle, and reduced the prevalence and intensity of Ascaris lumbricoides and Trichuris trichiura infection in the target age-class. A decline in infection was also observed in the 16-25 year age-class, even though less than 4% of adults received treatment. The study demonstrates that chemotherapy targeted only at children can be implemented within an existing health infrastructure, and can achieve an overall reduction in the prevalence and intensity of geohelminth infection.

The incidence of Encephalitozoon cuniculi in a commercial barrier-maintained rabbit breeding colony.

Between 1982 and 1987 sera from 4952 New Zealand White rabbits (Oryctolagus cuniculus) obtained from a single commercial supplier were tested for the presence of antibodies to Encephalitozoon cuniculi. A commercially available carbon immunoassay test kit was used. Initially 32.9% of the rabbits were seropositive with the number progressively decreasing to 2.3% by 1987. The reason for the significant decline in the incidence of infection was most likely due to a selection process for breeding stock instituted by the supplier based upon productivity, posture and weight of each animal.

Utilization of femoral head for estimating the skeletal burden of U and Pu in humans.

Uranium and Pu were determined in vertebrae, ribs and femoral head samples obtained from the same population. Vertebrae and rib samples were obtained at autopsy and femoral head samples were obtained from persons undergoing hip surgery. The results indicate that there was no statistically (p less than or equal to 0.05) significant difference between the mean concentration of 239,240Pu in vertebrae and ribs. Also, there was no significant difference between the mean concentration of 239,240 Pu in ribs and femoral head. Also, statistical tests were performed to see whether the mean concentrations of 238U and 234U in three different bones differ from each other. The results suggest that there was no statistically significant difference between vertebrae and ribs, vertebrae and head of the femur nor between ribs and femoral head. These results indicate that femoral head may be an appropriate substitute for vertebrae or ribs, the most commonly used bone for inferring the skeletal burden of U and Pu in human. Femoral head samples can be obtained from living persons undergoing hip surgery, while vertebrae and ribs are obtained only at autopsy.

Relationship of anxiety level and recall of information to the interval between orientation and first patient care day.

Sophomore students' responses to two different intervals between orientation and first clinical day in medical/surgical nursing were examined. Variables studied were anxiety state and ability to recall information which had been presented. Prior to orientation all students were given the Spielberger STAI-S and STAI-T anxiety scales. At the beginning of the first laboratory session the students completed the STAI-S scale and a teacher-made quiz on information presented in orientation. Students in Group I (n = 51) had their first laboratory one week after orientation. Group II (n = 39) had their first laboratory the day following orientation. There was no significant difference between the two groups on cumulative grade point average, beginning STAI-T or STAI-S. Likewise, there was no significant difference between the scores made on the quiz. (The validity and reliability of the quiz were not determined.) There was a significant difference between the two groups on changes in state anxiety from orientation to the first laboratory. Group I (laboratory one week after orientation) was more anxious than Group II (laboratory one day after orientation) (p = 0.024). Both groups were significantly more anxious in the Spring than Fall quarter (p = 0.034). It was concluded that anxiety related to a new clinical experience might be lessened if the first clinical day closely followed orientation. It was also noted that students may be more anxious in the Spring than in the Fall of the year.

Using control charts to help manage accounts receivable.

The relative performance of a healthcare organization's accounts receivable (AR) department is a critical factor affecting an organization's financial well-being. Park Nicollet Medical Center (PNMC), Minneapolis, Minnesota, changed the way it measured its AR department's performance, switching from the rolling averages method of performance measurement to the percentage collected method of performance measurement, and was able to improve its patient accounts management effort.