Vitamin D metabolism and calbindin (calcium-binding protein) in aged laying hens

Calbindin (calcium-binding protein) concentration, vitamin D metabolism and shell quality were investigated in young (7- to 9-mo-old) and aged (19- to 21-mo-old) laying hens consuming normal or low levels of calcium (Ca). Although egg weight and percent of cracked eggs were higher and egg production and shell density (mg/cm2) were lower (significantly, P less than 0.01) in aged hens, shell weight, plasma Ca and duodenal and egg shell gland calbindin were similar to those of young hens. Dietary Ca restriction reduced shell weight, shell density and structural bone and plasma Ca in both the young and aged birds. The production of 1,25-dihydroxycholecalciferol [1,25(OH)2D3] and its concentration in the plasma were higher in hens fed low dietary levels of Ca than in hens fed normal Ca levels only in the younger hens. However, a slightly higher production of 1,25(OH)2D3 and concentration of duodenal calbindin were also observed in severely Ca-restricted (1.4% Ca for 19 d) aged hens than in the younger hens. The results suggest that the aged hen loses its ability to adapt to changes in Ca intake or needs through mechanisms involving modulation of vitamin D metabolism.

Differential responses to dietary carbohydrates and fat of turkeys kept at various environmental temperatures

Interactions between environmental temperature and dietary energy sources were evaluated in 6 to 9-wk and 9 to 12-wk-old turkeys using weight gain, feed efficiency, and carcass fat as response criteria. The dietary variables (soybean oil or glucose) were added in five or six increments at the expense of each other or of the fiber supplements, keeping the minima for protein and amino acid/energy constant. The resulting diets were fed to birds kept at 10 and 27 C. Duplicate experiments were conducted for each mode of dietary variable addition. Parallel increases in body weight gain and feed efficiency were obtained at the two temperatures when fat replaced carbohydrates or fiber, thereby raising dietary energy density. Some responses of weight gain and feed efficiency at the two temperatures were obtained also with a graded isocaloric addition of fat but the response was significant only at 27 C and not at 10 C. A greater response of gain and feed efficiency to energy supplied by dietary glucose was obtained at 10 C as compared with 27 C. Dietary fat supplementation resulted in increased deposition of carcass fat when given together with energy or isocalorically regardless of environmental temperature. Carcass fat was increased by glucose-energy at the low temperature only.

Concentration of adrenocortical hormones in relation to cation homeostasis in birds

The effects of dietary Na+, K+, and Cl- and of acute stress on plasma levels of Na+, K+, aldosterone, and corticosterone were evaluated in vivo in birds. The dietary effects were studied in growing White Rock chicks, whereas the larger turkey was preferred for the acute stress study. Although plasma corticosterone remained unaffected, plasma aldosterone concentration decreased with increasing levels of dietary Na+ reaching a minimum at a dietary level of 72 meq/kg. Plasma Na+ remained unchanged when dietary Na+ levels increased up to 72 meq/kg but then rose with increasing Na+ intake. Plasma K+ was slightly depressed by high levels of dietary Na+ and increased by dietary K+. Neither plasma Na+ nor circulating adrenal hormones were affected by dietary K+ or dietary Cl-. Acute stress stimulated both aldosterone and corticosterone without any effect on the levels of the plasma minerals. The results suggest that of the two main corticoids, only aldosterone responds to dietary Na+ in chicks. This is in contrast to the indiscriminate stimulation of both hormones by stress, indicating different pathways of stimulation. The results also suggest that aldosterone is involved in the regulation of plasma Na+ only at low intakes of Na+ and that dietary K+ and Cl- are not involved in the aldosterone-Na+ feedback relationship.

Model of plasma calcium regulation: system oscillations induced by growth

The process of growth was included in a model for simulation of calcium homeostasis in the chick, using data of carcass composition and a model of growth and energy intake. Computer simulations, made for chickens between 0 and 10 wk of age, predicted oscillations in plasma calcium and its major regulatory systems. Analysis of the oscillations indicated a periodicity of approximately 55 h. The oscillations were proportionally dependent on the rate of growth, disappearing almost completely when growth rate was made equal to zero. Subject to the validity of the model, it is suggested that the oscillations in plasma calcium and some of the components of the regulatory systems are induced by a continuous perturbation (growth) resulting in a dual response to the main regulatory hormone, parathyroid hormone, one rapid with a response time of minutes (bone), and one delayed, with a response time of hours (calcium absorption via the metabolism of 1,25-dihydroxychole-calciferol). It is also suggested that some of the normal variance and some of the rhythmicity observed previously in various components of the calcium regulatory system may be the results of spontaneous oscillations.

Calcium dynamics: a model system approach

A computerized model used to simulate calcium metabolism in growing chicks combines growth equations with differential equations that account for the amount and action of various components of the plasma calcium regulating subsystems--intestine, kidney and bone. These in turn are modulated by the calcium-regulating hormones: parathyroid hormone and 1,25-dihydroxycholecalciferol. Simulation with this model indicated oscillations in the plasma calcium concentration in growing chicks under normal dietary conditions. The oscillations diminish in amplitude and finally disappear when dietary calcium concentrations are either reduced or elevated. These oscillations, triggered by the perturbation imposed by growth, are the result of the dual action of parathyroid hormone on bone on the one hand and on intestinal calcium absorption via the 1,25-dihydroxycholecalciferol synthesizing system on the other and the difference in the response time between the two subsystems. Simulation also predicts that at high or low intakes of calcium, the capacity of the control systems is exceeded and oscillation in plasma. calcium diminish and finally disappear. Bone calcium, simulated for different calcium concentrations, mimics documented experimental results.

Response of adrenal cells to parathyroid hormone stimulation

Dispersed adrenal cells of avian and bovine origin were incubated with human (h) 1-34 parathyroid hormone (PTH(1-34)), bovine (b) PTH(1-84), bPTH(3-34), avian (a) PTH, and with ACTH. Kidney tubular cells, the established target cells for PTH, were used for comparison. Cyclic AMP (cAMP) accumulation and steroid hormone (aldosterone and corticosterone) secretion were measured in response to the hormones. In the bovine adrenocortical cells PTH of both bovine and avian origin stimulated cAMP production, but the aPTH action was more pronounced. The maximal cAMP response of avian adrenocortical cells to aPTH was 15-fold greater than that of ACTH, but a 20-times higher concentration of aPTH was required to reach half-maximal response. Avian PTH stimulated steroid hormone secretion in the chick adrenocortical cells, but the induced secretion was similar to that induced by ACTH, despite the difference in cAMP accumulation. Human PTH(1-34) and bPTH(1-84), which stimulated cAMP production in kidney cells, and the conventional antagonist bPTH(3-34) inhibited aPTH stimulation of cAMP accumulation in avian adrenocortical cells, but did not interfere with ACTH action. Furthermore, cAMP stimulation by aPTH and ACTH in avian adrenal cells was additive. The results establish the adrenal as a target organ for PTH, and suggest that the PTH acts through specific receptors, distinct from those for ACTH.

Serodiagnosis of invasive aspergillosis in patients with hematologic malignancy: validation of the Aspergillus fumigatus antigen radioimmunoassay

Six hundred sixteen sera from 79 hematology patients admitted on 152 occasions were analyzed for validation of the Aspergillus fumigatus antigen radioimmunoassay (RIA). Invasive aspergillosis developed on 24 admissions of 22 patients. Maximal antigenic activity was significantly higher in patients with invasive aspergillosis than in controls (P less than .0005). At the level of antigenic activity selected as the cutoff value, the sensitivity of the RIA was 74%, the specificity 90%, the positive predictive value 82%, and the negative predictive value 85%. Antigen was detected before invasive aspergillosis was suspected during 30% of admissions and before pathological or even preliminary microbiological evidence for disease in 46%. In 17 (77%) of the 22 episodes of pulmonary aspergillosis, the RIA would have been the first positive diagnostic test for aspergillosis or would have confirmed a diagnosis established by other means. Overall, the test would have been of clinical usefulness in diagnosis, management, and prognosis in 80% of 16 fatal cases.

Field rickets in turkeys: relationship to vitamin D

Thirty-two outbreaks of leg disorders in turkeys were investigated during 1981-1985. Among them, 22 were characterized by a low percentage of bone ash and were considered as field rickets. Most of the field rickets cases exhibited reduced plasma calcium and inorganic phosphorus. Plasma 25-hydroxyvitamin D3 and intestinal calcium-binding protein were lower in the rachitic than in normal turkeys. These symptoms are typical of rickets resulting from vitamin D deficiency. The vitamin D3 equivalence of a diet that had been fed during field rickets outbreaks was assayed biologically and found to be 111 micrograms/kg diet, about eight times the minimal requirement. In two other cases no symptoms of rickets were observed in turkeys fed diets that had been previously consumed during field rickets outbreaks. The results indicate that in some cases of field rickets there was no involvement of dietary factors and confirm a previous suggestion that field rickets may result from defects in metabolism of vitamin D3, or in its expression.

Final report of the phase I trial of single-dose WR-2721 [S-2-(3-aminopropylamino)ethylphosphorothioic acid]

Two hundred one patients were entered in a single-dose phase I trial of WR-2721 [S-2-(3-aminopropylamino)ethylphosphorothioic acid]. Major toxic effects included emesis and hypotension. The observed minor toxic effects were somnolence and sneezing. Two infusion schedules were tested: long-infusion time, which fixed the rate, but varied total time; and short-infusion time, which varied the rate, but fixed the time to 15 minutes. Emesis was significantly influenced by infusion time; the long schedule caused a 57% incidence whereas the short schedule caused only a 28% incidence. Within the long-infusion group, higher-dose patients and women were more likely to vomit. Although only 15% of the entire group had hypotension, the long-infusion schedule had a hypotension incidence of 23%; the short schedule had an incidence of only 3% (P less than 0.0005). Within the long-infusion group, dose and tumor site significantly influenced the incidence of hypotension. No factors were associated with these toxic effects in the short-infusion schedule. However, certain toxic effects were too infrequent to detect significant differences. For future trials we recommend 740 mg/m2 infused in 15 minutes. With this schedule, vomiting was seen in 25% of infusions and hypotension was seen in only one of 68 infusions. To date, no delayed toxic effects have been detected in any organ system, and the trial resulted in no toxic deaths.

Reduced affinity of intestinal receptors for 1,25-dihydroxycholecalciferol in phosphorus-deficient chicks

The binding of 1,25-dihydroxycholecalciferol (1,25-(OH)2D3) to its intestinal receptor was studied in chicks fed a phosphorus (P)-deficient diet. The equilibrium association constant (Ka) was determined by Scatchard analysis. Association (Kass) and dissociation (Kdis) rate constants were determined in experiments on hormone uptake and release respectively. The Ka, determined at 4, 12 and 19 degrees C, decreased progressively during P deficiency, due to the decrease in Kass, but Kdis was not affected. During prolonged P deficiency the concentration of binding sites (Nmax) also decreased. Duodenal calcium-binding protein (CaBP) increased during 10 days of P deficiency and then decreased. The long-term decrease in receptor affinity and Nmax may account for the observed reduction in receptor occupancy and the decrease in the high level of intestinal CaBP stimulated during early P deficiency. The resulting decrease in Ca absorption may minimize the hypercalcaemia induced by the deficiency.

Relation of human T lymphotropic virus type III antibodies to T lymphocyte subset abnormalities in hemophiliac patients

The relationship of T lymphocyte subset abnormalities and the presence of antibodies to the human T lymphotropic virus type III (HTLV-III) was evaluated in 66 adult patients with hemophilia. Positive test results for antibodies to HTLV-III were observed in 62 percent of patients with hemophilia A and 9 percent of patients with hemophilia B. Patients with HTLV-III antibodies had lower percentages and numbers of T helper (T4) cells and increased percentages of T suppressor (T8) cells compared with percents in patients without antibodies to HTLV-III. The mean T4/T8 ratio for antibody-negative patients was 1.45 compared with 0.65 for antibody-positive patients (p less than 0.0005). These abnormalities were more apparent among hemophiliac patients who received factor VIII concentrates. The strong association of lymphocyte subset abnormalities and seroreactivity to this virus suggests that infection by HTLV-III has occurred in this population rather than a passive exposure to viral antigens contained in factor concentrates.

Parameter estimation for ligand binding systems kinetics applied to 1,25-dihydroxycholecalciferol

A mathematical analysis of the kinetics of the hormone-receptor interaction was applied to the 1,25-dihydroxycholecalciferol-intestinal receptor system. The exact analytical solution and the numerical integration of the kinetic equation were installed in a Statistical Analysis System (SAS) computer program to estimate the rate constants of the reaction. Estimates of the parameters obtained by these two methods are similar, demonstrating that the numerical integration can be combined with the nonlinear regression procedure for least-squares parameter fitting using a simple SAS program. This enables estimation of kinetics rate constants when the kinetic equation cannot be solved analytically. The ratio of the rate constants (ka/kd) found by the nonlinear procedure is close to the independently determined equilibrium (Scatchard) constant in the nonlinear analysis.

Comparison of allogeneic bone marrow transplantation and chemotherapy in adult acute nonlymphocytic leukemia. An Eastern Cooperative Oncology Group Study

To compare the value of ABMT (allogeneic bone marrow transplantation) in first or second remission vs. conventional chemotherapy in adults with acute nonlymphocytic leukemia, we examined retrospectively the outcome of a recently completed chemotherapy trial. We evaluated the survival of patients, with and without histocompatible siblings, who were less than or equal to 45 years old and who had achieved initial complete remission. Of 20 patients who were referred by their physicians for ABMT in first remission, seven relapsed (median duration of remission, 4 months) prior to ABMT, three refused, and 10 underwent ABMT. Nine patients received ABMT in second remission. In comparison to the results of chemotherapy in patients who lacked histocompatible siblings (median duration of survival, 18.5 months), the survival of patients transplanted in first remission was worse (median, 8 months), whereas the survival of patients transplanted in second remission was substantially better (median greater than 22 months). Although ABMT in second remission clearly offers the potential for long-term survival not available by means of conventional chemotherapy, the value of ABMT in first remission remains uncertain.

Relationship between endogenous cyclic AMP production and steroid hormone secretion in chick adrenal cells

Dispersed chick adrenal cells were incubated with either ACTH, cholera toxin or forskolin. All three agents stimulated cyclic AMP accumulation and secretion of corticosterone and aldosterone by the dispersed cells. The dose-response to ACTH was similar for cyclic AMP and corticosterone but aldosterone secretion appeared to be more sensitive to ACTH stimulation. Concentrations higher than 10(-8) M of ACTH caused suppression of corticosterone output but not of cyclic AMP accumulation or aldosterone secretion. A significant cyclic AMP accumulation occurred within 30 min of exposure to ACTH whereas significant increases in steroid secretion were observed only after 30 min. An early increase (within 30 min) in cyclic AMP accumulation with both cholera toxin and forskolin was not accompanied by any significant stimulation of steroid secretion, which occurred only after 120 min. The results with the avian adrenal cells are consistent with the thesis that steroid production in the adrenocortical cells is stimulated by cyclic AMP-dependent pathways, whereas steroid release may be modulated by others.

Factors associated with psychological distress in cancer patients

We studied the mental health of 1,278 patients with cancer and 645 family members of patients with cancer to delineate clinical and demographic characteristics associated with poor psychological status. For both patients and their matched relatives, there was a direct relationship between poorer mental health scores and younger age. Highly significant age differences emerged as well for subscale scores of anxiety, depression, and general positive affect in patients, and for depression, emotional ties, and loss of control in relatives. Treatment status, performance status, and sex also contributed significantly to mental health scores. Patients at greatest risk for psychological problems are young, female, receiving palliative or active treatment as opposed to follow-up care, and symptomatic or not fully ambulatory. Clinicians should be alert to the potential for psychological problems among patients in these categories.

Regulation of kidney calcium-binding protein in the bird (Gallus domesticus)

The possible involvement of plasma calcium and 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] in the regulation of the concentration of kidney calcium-binding protein (CaBP) was investigated. Chicks were fed diets varying in Ca2+ and P, with or without vitamin D. CaBP and 1,25(OH)2D3 were determined by competitive binding assays. A significant correlation between plasma and kidney 1,25(OH)2D3 was found, the linear regression equation of best-fit was plasma 1,25(OH)2D3 = 0.14 + 1.56 kidney 1,25(OH)2D3. In the vitamin D-fed chicks, kidney CaBP varied independently of the circulating or organ level of 1,25(OH)2D3 (P greater than 0.05), but was lower in the vitamin D-deficient than in the vitamin D-fed birds. A significant correlation was observed between kidney CaBP and plasma calcium (Cap). The regression equations were CaBP = Cap/(85.57-4.00 Cap) (R = 0.845) and CaBP = 0.0558 + 0.0404 Cap (R = 0.749), for vitamin D-treated and vitamin D-deficient chicks, respectively. The results suggest that the concentration of kidney CaBP is modulated by plasma calcium, but one or more of the vitamin D metabolites may be required for its synthesis.

Carcass minerals in chickens (Gallus domesticus) during growth

Moisture, sodium, potassium, calcium, phosphate and magnesium were determined in the carcass of male chickens (Gallus domesticus) between the ages of 1 and 70 days. Moisture decreased rapidly during the first 3 days of life, followed by a more moderate decline. Sodium and potassium concentrations decreased with age, but not in a parallel fashion. Some of the changes with age could be explained on the basis of an extra- and intracellular fluid shifts. Calcium and phosphate concentration increased with age, reflecting skeletal calcification. Carcass magnesium concentration increased during the first 3 days of life and did not change significantly thereafter.

Invasive pulmonary aspergillosis in adult acute leukemia: clinical clues to its diagnosis

Invasive pulmonary aspergillosis, a leading cause of morbidity and mortality in patients with acute leukemia, is difficult to diagnose antemortem because its signs and symptoms are ill-defined. To refine the clinical description of this infection, we reviewed our experience with 15 pathologically documented cases of invasive pulmonary aspergillosis in a population of 60 patients treated for acute leukemia. Findings occurring significantly more often (P less than or equal to .001) among cases than controls included pleuritic chest pain; acute sinus tenderness, and nasal discharge, epistaxis and eschar; rales; development of multilobar infiltrates after the 14th hospital day; and presence of nodular or cavitary infiltrates. In addition, patients with invasive pulmonary aspergillosis had a significantly prolonged duration of granulocytopenia, more febrile days and febrile episodes without a fever diagnosis and more febrile days on antibiotics (P less than or equal to .001 in all). This complex of findings should improve the clinician's ability to diagnose invasive pulmonary aspergillosis in patients with acute leukemia.

The role of lymph node dissection for clinical stage I malignant melanoma of intermediate thickness (1.51-3.99 mm)

The survival times of patients who had an elective regional lymph node dissection was compared with that of those who did not undergo the procedure in a database of 72 patients with clinical Stage I melanoma of intermediate thickness (1.51-3.99 mm). All of the patients had been followed for 5 years or longer or until death. No significant differences were found in other reported prognostic factors, suggesting that the two groups were comparable. By multivariate analysis, a low mitotic rate, intermediate patient age, and the presence of an infiltrative lymphocytic response were found to be associated with favorable survival. There did not appear to be any association of elective regional lymph node dissection with survival; and it was concluded that such therapy should not be regarded as "standard" for clinical Stage I melanoma of intermediate thickness.

Movement and absorption of major minerals and water in ovine gastrointestinal tract

Movement of calcium, chloride, magnesium, potassium, sodium, and water in the intestine of sheep was determined with cerium-141 as an unabsorbed reference substance. Net secretion of phosphorus and sodium, but not of potassium and calcium, was observed to the rumen. Water disappeared from the omasum and was secreted in the abomasum. Chloride secretion occurred in the omasum and more in the abomasum. Extensive secretion in the duodenum increased flows of sodium and potassium 8 to 9 times; of calcium, chloride, and phosphorus 3 to 6 times; of magnesium 1.3 times; and of water 12 times. Reabsorption was rapid in the small intestine, the major site of disappearance of all ions. Rates of disappearance decreased with increasing distance from the pylorus. Little further net disappearance of calcium, phosphorus, magnesium, or potassium was found in the large intestine, whereas water, sodium, and chloride disappearance continued. Overall absorption of sodium, potassium, and chloride was approximately 90%, of phosphorus 63%, of calcium 38%, and of magnesium 71%. This study highlights the importance of endogenous secretions in mineral absorption in the sheep.

Erythema chronicum migrans and Lyme disease

Lyme disease is an inflammatory disorder with a wide spectrum of clinical manifestations that involve the skin, joints, heart, and nervous system (1-4). Initially described in 1977 and named after the rural town in Connecticut where the first cases were detected in 1975, Lyme disease has now been recognized in at least 24 states (5-7), Canada (8), Australia (9), France (10), Switzerland (11), and Germany (12), and in individuals who travel to or spend time in areas known to be endemic for this disorder (13).

Discriminant scorecard for diagnosis of invasive pulmonary aspergillosis in patients with acute leukemia

Invasive pulmonary aspergillosis, a serious opportunistic infection in adult patients with acute leukemia, is difficult to diagnose antemortem. To identify patients with invasive pulmonary aspergillosis without reliance on invasive diagnostic procedures, a discriminant scorecard for invasive pulmonary aspergillosis based on clinical parameters was evaluated in a three-phase study. In phase I, the records of 62 patients, including 15 with invasive pulmonary aspergillosis, were reviewed. Eleven clinical parameters distinguished patients with invasive pulmonary aspergillosis from control subjects. These parameters were combined into a discriminant scorecard. In phase II, the discriminant scorecard was validated by a blinded, retrospective review of 94 consecutive admissions. The discriminant scorecard score was highly associated with the clinical outcome (p less than 0.0005). The sensitivity of the discriminant scorecard was calculated as a range from 62.9 to 92.8 percent and the specificity as a range from 87.5 to 98.3 percent. In phase III, the clinical utility of the discriminant scorecard was determined by its prospective application to 49 consecutive patient admissions. The discriminant scorecard identified patients with invasive pulmonary aspergillosis at an average of 4.1 days prior to clinical recognition of the disease and initiation of amphotericin B therapy. The discriminant scorecard outperformed a complex function based on multiple linear regressions, was easy to use, and did not require difficult calculations. Thus, for this patient population, the discriminant scorecard was an accurate, useful noninvasive screening test for invasive pulmonary aspergillosis. The scorecard allows more rapid clinical identification of patients with this infection and could lead to improved patient survival through earlier diagnostic and therapeutic intervention.

Fertility of fresh and stored turkey spermatozoa in the presence or absence of glucose or fructose in the suspension medium

Turkey hens were inseminated with either fresh or stored (4 hr at 15 C) semen suspended in a sugar-free medium or one containing 15 mM glucose or fructose. Rates of fertilization of eggs collected for 15 days after insemination were not affected by the presence or absence of glucose or fructose in the medium nor by storage.

High-dose oral metoclopramide. An effective antiemetic agent

Seventy-six patients receiving cisplatin and noncisplatin-containing cancer chemotherapy were treated with an outpatient phase II metoclopramide regimen. The program consisted of an outpatient intravenous loading dose of metoclopramide before chemotherapy, followed by oral metoclopramide at 1, 3, 5, and 8 hours after chemotherapy. Three oral dose levels were evaluated. Treatment with 2 mg/kg/dose or 100 mg/dose resulted in no vomiting in 53% of 65 evaluable patients, and 0-2 episodes of emesis in 74%. Oral doses of 50 mg/dose were less effective, preventing emesis in 18%. This trial demonstrated the antiemetic effectiveness of high-dose oral metoclopramide in a new schedule designed for the outpatient setting. The side effects included restlessness (51% of patients), dystonic reactions (9%), and gastrointestinal complaints (41%).