Thyroid hormones affect plasma ghrelin and obestatin levels.

Using radioimmunoassay, the effects of thyroid hormones on plasma total ghrelin (Gh) and obestatin (Ob) concentrations were evaluated in thyrotoxic patients with an excess of thyroid hormones and in hypothyroid patients lacking endogenous thyroid hormones. 24 patients with thyrotoxicosis, 25 hypothyroid patents after total thyreoidectomy performed due to thyroid cancer, and 17 control subjects were examined. Compared with the controls, the ghrelin and obestatin were elevated in hypothyroidism, while they were decreased in thyrotoxicosis. The plasma Gh and Ob levels differ depending on the thyroid function. In thyroid hormones deficiency, plasma Gh and Ob are increased, while in patients with excess of thyroid hormones, the levels of both Gh and Ob are definitely lower. Gh/Ob ratio is higher in hypothyroidism than in control subjects and thyrotoxic patients.

Leptin, soluble leptin receptors, free leptin index, and their relationship with insulin resistance and BMI: high normal BMI is the threshold for serum leptin increase in humans.

Leptin binds to the soluble form of its receptor (sOB-R). Leptin and sOB-R balance (free leptin index, FLI) reflect leptin activity. Leptin correlates with obesity and insulin resistance, but it remains uncertain whether sOB-R and FLI also do the same. Therefore, the aim of this study was to measure serum leptin, sOB-R, and FLI, and evaluate their associations with BMI and insulin resistance. We studied 145 obese and 49 nonobese humans. Obesity was defined according to WHO (BMI >30 kg/m (2)). Results are given as: median and interquartile range, obese vs. nonobese, respectively. Leptin (ng/ml): 30.83, 37.27 vs. 8.31, 10.04; sOB-R (ng/ml): 17.62, 17.05 vs. 27.25, 11.30; FLI: 231.2, 310.0 vs. 30.85, 27.77; HOMA: 5.99, 6.64 vs. 3.92, 4.52; p<0.001 for all. Serum leptin, sOB-R, and FLI did not correlate with insulin resistance separately in obese and nonobese humans. Leptin and FLI, but not sOB-R, were associated with insulin resistance in obese and nonobese subjects examined together. Leptin, sOB-R and FLI differed between obese and nonobese humans, and, except sOB-R, correlated with BMI. In piecewise linear regression, BMI threshold where leptin increased was 24.6 (r=0.5969, p=0.00016 and <0.00001). Leptin and its free index, but not sOB-R, correlate with BMI only in a mixed obese and nonobese human cohort, and not in isolated obese or nonobese groups. Moreover, BMI threshold where leptin starts to increase is 24.6 kg/m (2), which is lower than the cutoff for overweight. Under the conditions, metabolic abnormalities may occur in parallel to much lower BMI levels as expected so far.

Validation of methodologies for quantifying isolated human islets: an Islet Cell Resources study.

BACKGROUND: Quantification of islet mass is a crucial criterion for defining the quality of the islet product ensuring a potent islet transplant when used as a therapeutic intervention for select patients with type I diabetes. METHODS: This multi-center study involved all eight member institutions of the National Institutes of Health-supported Islet Cell Resources Consortium. The study was designed to validate the standard counting procedure for quantifying isolated, dithizone-stained human islets as a reliable methodology by ascertaining the accuracy, repeatability (intra-observer variability), and intermediate precision (inter-observer variability). The secondary aim of the study was to evaluate a new software-assisted digital image analysis method as a supplement for islet quantification. RESULTS: The study demonstrated the accuracy, repeatability and intermediate precision of the standard counting procedure for isolated human islets. This study also demonstrated that software-assisted digital image analysis as a supplemental method for islet quantification was more accurate and consistent than the standard manual counting method. CONCLUSIONS: Standard counting procedures for enumerating isolated stained human islets is a valid methodology, but computer-assisted digital image analysis assessment of islet mass has the added benefit of providing a permanent record of the isolated islet product being evaluated that improves quality assurance operations of current good manufacturing practice.

Isolation and characterization of rabbit endocervical cells.

Three cytologically distinct cell populations were identified, in addition to ciliated cells, when a unit gravity sedimentation procedure was applied to pronase-dispersed rabbit endocervical cells. Two of these cell populations contained histochemically distinguishable (periodic acid- Schiff [PAS]) mucoproteins and were designated vacuolated and granular PAS-positive cells. The third, designated as vacuolated PAS-negative, did not contain secretory granules. Cell integrity was confirmed by trypan blue dye exclusion, [(3)H]leucine incorporation, and ultrastructural analysis. To demonstrate hormonal modulation of endocervical cell morphology, cell distribution profiles were compared from animals in different hormonal states. In the absence of estrogen dominance, PAS- positive cells from 5-d pseudopregnant rabbits were reduced 50 percent, while vacuolated PAS-negative cells increased fourfold as compared with estrous cell populations. The PAS-positive cells sedimented toward the top of the gradient where the bovine serum albumin concentrations were lower, consistent with a reduction in the number of secretory granules. In the sustained absence of ovarian steroid hormones, the number of PAS-positive mucous cells from ovariectomized rabbits was reduced to only 4 percent of the total endocervical cell population. The biosynthetic capacity of isolated endocervical cells was determined by incubating the three nonciliated cell populations from estrous and 5-d pseudopregnant rabbits for 36 h with the mucin precursor, [(14)C]N-acetyl- D-glucosamine. Only PAS-positive cells incorporated significant amounts of labeled precursor. This study indicates that steroid hormones influence cervical secretions by modulating the type of endocervical cells.

Effectiveness of a baking soda toothpaste delivering calcium and phosphate in reducing dentinal hypersensitivity.

OBJECTIVE: The purpose of this controlled clinical trial was to determine the effectiveness and safety of a single-phase dentifrice that delivers calcium, phosphate, and fluoride to the tooth surface (Arm & Hammer Enamel Care for Sensitive Teeth toothpaste, United Kingdom) in reducing dentinal hypersensitivity. METHODS: Two-hundred and eight qualifying subjects were randomly assigned to either the Enamel Care dentifrice group or a control dentifrice group, and brushed twice daily with their assigned dentifrice for eight weeks. Pain/discomfort in response to a thermal stimulus was assessed at baseline, week 4, and week 8 using a Visual Analogue Scale (VAS; primary outcome variable) and the Schiff Thermal Sensitivity Scale (STSS; secondary outcome variable). After eight weeks, volunteers from the Enamel Care group were switched to the control dentifrice and participated in a second eight-week study to determine the degree of persistence of pain reduction. RESULTS: Both groups had statistically significant VAS score reductions from baseline at weeks 4 and 8, with mean VAS scores in the Enamel Care group decreasing by 45.6% at week 4 and 61.1% at week 8 (p < 0.0001). Enamel Care was statistically significantly more effective than the control at weeks 4 and 8, with respective mean VAS reductions of 63% (p < 0.0001) and 33% (p = 0.0004) greater than the control. Consistent with the VAS score results, the Enamel Care group had respective statistically significant STSS score reductions of 77% and 58% greater than the control group (p < 0.0001). The reductions in dentinal hypersensitivity seen in the Enamel Care group at week 8 persisted for an additional eight weeks, during which the subjects discontinued use of Enamel Care and brushed with the control dentifrice. CONCLUSION: Enamel Care for Sensitive Teeth toothpaste (United Kingdom) is an effective dentifrice for the management of dentinal hypersensitivity, and its efficacy persists for a least eight weeks following discontinued product use.

Serum adiponectin concentrations are not related to glycosylated hemoglobin levels (HbA1c) in obese diabetic and non-diabetic caucasians.

UNLABELLED: Although circulating adiponectin has been inversely correlated with obesity, type 2 diabetes and serum glycosylated hemoglobin (HbA1c) in humans, contradictory reports on that subject exist. In this study, serum concentrations of adiponectin in obese non-diabetic and diabetic humans were measured to examine whether they were associated with levels of HbA1c. The WHO definitions of obesity and diabetes were used. One hundred and five obese euglycemic subjects and 49 obese diabetics (aged 51+/-6.9, and 52+/-6.7 years, respectively) were studied. Their BMI, HbA1c and % of body fat were measured. Adiponectin was determined by an enzyme-linked immunosorbent assay. Although the serum adiponectin concentrations differed between diabetics and non-diabetics ( P<0.01), they were not correlated with HbA1c (r=-0.0814; P=0.5823, and r=-0.1861; P=0.1099, for diabetics and non-diabetics, respectively). Both diabetics and non-diabetics were segregated into tertiles according to their HbA1c levels. Plasma adiponectin did not differ significantly between the high (H), intermediate (I), and low (L) HbA1c tertiles. CONCLUSION: Concentrations of adiponectin were not correlated with levels of glycosylated hemoglobin in the diabetic and non-diabetic subjects examined.

Effectiveness of the iodine prophylaxis model adopted in Poland.

OBJECTIVE: Most of the Polish territory has been classified as an iodine-deficient and endemic goiter area according to the International Council for Control of Iodine Deficiency (ICCIDD) criteria. In 1997 the obligatory model of iodine prophylaxis was implemented. Our investigations were aimed at the effectiveness of iodine prophylaxis in Poland. METHODS: We assessed urinary iodine excretion and goiter prevalence in 5663 children aged 6-12 yr. The population of children from the same 27 schools was investigated from 1992 to 1994 (1406 girls and 1244 boys) and from 1999 to 2005 (1563 girls and 1450 boys) using identical laboratory and ultrasound methods. RESULTS: We found significant increase in iodine urinary concentration (median 52 microg/l vs 93 microg/l, p<0.001) with accompanying drop in goiter prevalence (29.6% vs 5.2%, p<0.001) after implementation of iodine prophylaxis. Iodine excretion distribution changed significantly after 1997 with an increase in the percentage of children with iodine urinary concentration above 100 microg/l from 10.8% to 45.4%, respectively. A significantly higher iodine urinary concentration was observed in lowlands compared to uplands both before and after implementation of iodine prophylaxis (median, 50 microg/l vs 57 microg/l and 86 microg/l vs 114 microg/l, respectively, p<0.001). The goiter prevalence did not differ between girls and boys from 1992 to 1994 (28.8% vs 30.5%, p=0.35) and 1999 to 2005 (5.5% vs 4.9%, p=0.45). CONCLUSIONS: Implementation of the new model of iodine prophylaxis in Poland in 1997 has led to significant increase in iodine urinary concentration and decrease in goiter prevalence among Polish schoolchildren. In the youngest group of children (6-8 yr olds), prevalence of goiter decreased to 3.2%--i.e. below endemic levels.

Myocardial perfusion SPECT with dipyridamole stress test in cardiac syndrome X.

UNLABELLED: Cardiac syndrome X defines patients with typical anginal chest pain, a positive exercise ECG stress test and angiographically normal coronary arteries. AIM of this study was to evaluate the role of myocardial perfusion SPECT with dipyridamole stress in the diagnosis of cardiac syndrome X. PATIENTS, METHODS: 68 patients with syndrome X aged 32 to 60 years were subjected to myocardial imaging using (99m)Tc-MIBI according to the two-days protocol: at rest and after dipyridamole infusion. Semiquantitative evaluation of the images was based on the assessment of (99m)Tc-MIBI uptake in 17 myocardial segments using a 5-points scale (0 point -- normal uptake, 4 points -- no uptake). Scores obtained in each segment were summed up, constituting the summed rest score (SRS) and summed stress score (SSS). RESULTS: Mean SRS was 7.9 +/- 4.8 and mean SSS was 7.2 +/- 4.4 (non-significant difference). Individual comparison of SRS and SSS values revealed three patterns of scintigraphic images: 1) in 25 patients (36.8%), a paradoxical improvement of perfusion at stress images was found, 2) in 23 patients (33.8%), the myocardial perfusion deteriorated after dipyridamole, 3) in 20 patients (29.4%), no significant change of the myocardial perfusion between rest and stress images occurred. CONCLUSIONS: In cardiac syndrome X, myocardial SPECT with dipyridamole stress shows different patterns of myocardial perfusion that reflects heterogeneity of this pathology.

The influence of growth hormone (GH) therapy on cardiac performance in patients with childhood onset GH deficiency.

OBJECTIVE: There is accumulating evidence that growth hormone (GH) plays an important role in the maintenance of normal cardiac growth and function. Abnormalities in left ventricular diastolic function and impairment of systolic function have also been reported in patients with GHD. In this study, we investigated the effects of 12 months GH replacement therapy on cardiac functional indices measured by echocardiography, the ECG stress test and SPECT imaging. DESIGN: Sixteen patients with childhood onset GHD (age 42.3+/-13.1 years, 10 males) were investigated before, and after, 12 months of GH treatment at a dosage of 0.02 IU/kg/day (7 microg/kg/day). The GH administration resulted in serum IGF-I levels within the normal range in all the patients. The following investigations were performed initially and after 12 months: electrocardiography, systolic and diastolic blood pressure, heart rate measurement, a complete Doppler-echocardiographic examination, treadmill exercise test and Technetium-99m sestamibi single-photon emission computer tomography (SPECT) imaging at rest and after exercise. RESULTS: Echocardiography showed improvement in left ventricular systolic function after GH treatment. End-systolic volume fell from 29.9+/-12.4 to 24.4+/-6.9 ml (p<0.05) and the ejection fraction increased from 56.2+/-7.2% to 63.2+/-6,1% (p<0.01). Left ventricular diameter and wall thickness did not change after GH treatment, although systolic increase in interventricular septum thickness (IVS%) and systolic increase in posterior wall thickness (PWT%) increased significantly (IVS% 52.2+/-31.9% vs. 67.3+/-30.4% and PWT% 48.7+/-20.2% vs. 58.0+/-17.7%, p<0.01, p<0.01, respectively). Contractile function, measured at midwall level, improved as left ventricular midwall fractional shortening (MWS) increased (16.11+/-6.55 vs. 23.30+/-5.89 %, p<0.01) and stress-corrected MWS increased between the examinations performed before and after 12 months of GH treatment (90.97+/-36.66 vs. 133.10+/-32.84 %, p<0.01). Diastolic function did not change, as assessed by early diastolic flow (E), diastolic flow secondary to atrial contraction (A), or the E/A ratio. The LV-mass index did not change significantly after GH treatment (78.4+/-22.1 vs. 81.9+/-21.1g/m(2)). After 12 months of GH treatment the myocardial performance index (MPI) decreased significantly from 0.483+/-0.146 at baseline to 0.410+/-0.086 at the end of the study (p<0.05). There was a trend towards an increase in exercise duration and capacity after GH treatment but the differences did not reach levels of statistical significance. SPECT imaging basally and after 12 months showed normal myocardial perfusion at rest and after exercise in all the patients. In conclusion, GH replacement therapy in adults with GHD demonstrated the beneficial effects on cardiac functions.

Iodine prophylaxis intensification. Influence on radioiodine uptake and activity of 131I used in the treatment of hyperthyroid patients with Graves' disease.

UNLABELLED: Poland, a country with mild/moderate iodine deficiency introduced an obligatory iodination salt system in 1996. AIM: To compare the results of radioiodine (131I) uptake after 5 h and 24 h with the activity of radioiodine used in the treatment of hyperthyroid patients with Graves' disease in the years 1995 and 2003. PATIENTS, METHODS: The marker of iodine content in the diet was urinary iodine excretion. 1000 randomly chosen patients (average age: 46 +/- 12 years) were included in the study. Every patient had routinely estimated radioiodine uptake after 5 h and 24 h and the activity of 131I was calculated using scintigraphy and ultrasonography of the thyroid gland. Urinary iodine excretion in samples from year 1995 and 2003 was also determined in some patients and healthy volunteers. RESULTS: The iodine load in the diet increased from 66 microg (average) in the year 1995 to 115 microg in the year 2003. Thyroid radioiodine uptake was 40% lower in comparison with the results from 1995. The average activity of 131I given in the year 2003 (10 mCi) was about 40% higher than in the year 1995 (7 mCi). CONCLUSION: There was significant negative correlation between higher iodine content in the diet and lower values of radioiodine uptake, which led to the application of the higher activity of 131I during treatment.

Correlation of ST-segment depression during ambulatory electrocardiographic monitoring with myocardial perfusion and left ventricular function.

To assess the relation between silent ischemia and objective markers of ischemia we compared ambulatory electrocardiographic (AECG) monitoring, exercise stress testing, and technetium-99m methoxyisobutyl isonitrile single-photon emission computed tomography (SPECT) in 68 patients with coronary artery disease. ST-segment depression at AECG monitoring occurred in 40%, exercise testing was positive in 88%, and SPECT was abnormal in 98% of patients. Patients with ST-segment depression had a higher incidence of 3-vessel disease (70% vs 45%, p = 0.04), shorter duration of exercise (267 +/- 109 vs 416 +/- 167 seconds, p < 0.01), lower workload achieved (5.1 +/- 1.9 vs 7.6 +/- 2.8 METs, p < 0.0002), and a greater extent of ischemia at scintigraphy (p = 0.01). Patients with a total ischemic time of >30 minutes in a 24-hour period had a lower ejection fraction (48 +/- 21% vs 70 +/- 9%, p = 0.001), a higher perfusion index at rest (2.4 +/- 0.6 vs 1.6 +/- 0.6, p = 0.001), and a greater number of segments with fixed perfusion defects (4.1 +/- 3.7 vs 1.3 +/- 1.8, p = 0.02) in comparison with those who had a shorter ischemic time. We conclude that AECG monitoring fails to identify a substantial proportion of patients with objective markers of ischemia; however, ST-segment depression reflects more significant disease. Longer total ischemic time correlates with the area of myocardial damage but not with other markers of ischemia.

Uptake of human recombinant tissue-type plasminogen activator by rat hepatocytes in vivo: an electron microscope autoradiographic study.

The hepatic uptake of recombinant human tissue-type plasminogen activator (tPA) has been studied by electron microscope autoradiography (EMARG) of serial hepatic biopsies taken from anaesthetized, laparotomized rats following intravenous injection of 125I labeled tPA. Serial blood samples showed both radiolabel and biologic activity to be eliminated from circulation with an initial half-life of approximately two minutes. Grain half-distance distribution profiles and grain density analysis showed that the para-sinusoidal region of the hepatic parenchymal cell is the only site in the liver to concentrate radiolabeled tPA after intravenous injection. These data support the hypothesis that the parenchymal cell is the principal cell responsible for hepatic clearance of tPA from circulation and suggest that receptor mediated endocytosis may be the mechanism of cellular uptake.

Influence of some matrix elements on atomization of cobalt in graphite-furnace atomic-absorption spectrometry.

The influence of some chlorine, sulphur and phosphorus compounds on cobalt atomization in a graphite cuvette has been investigated. On the basis of atomization curves and estimated atomization energies the mechanisms of several processes have been proposed. Excess of chlorine is responsible for losses of cobalt as chloride and also for formation of a compound with graphite which causes atomization to occur at a temperature 300 K higher than that in the absence of graphite. In presence of sulphur, the atomization goes through sulphide formation but a reaction with graphite is also suspected. The presence of phosphorus significantly increases the rate of atomization, which enhances the peak height for cobalt. The mechanism probably involves dissociation of phosphate salts.

Semiquantitative analysis of SPECT images using 99Tc(m) -HMPAO in the treatment of brain perfusion after the attenuation correction by the Chang method and the application of the Butterworth filter.

The aim of this work was to optimize the parameters for semiquantitative analysis with regard to the average number of counts per pixel in tomographic projections. The analysed studies were divided into three groups, proportionally, to average the counts per pixel. The analysis of results proved the dependence (P<0.05) between the average geometric contrast of images with the maximum counts per pixel higher than 500, reconstructed with the cut-off frequency fc=0.50fn, and the standard image. Also, the same dependence was found between the group with an average of 200 counts per pixel and the standard image at the cut-off frequency fc=0.40fn. The analysis of the attenuation coefficient, c, showed significant differences. The attenuation coefficient c=0.12 cm-1 as accepted for further studies. Optimization of the matrix order of interpolation filter proved increasing of contrast with decreasing size of the matrix. In conclusion, according to the average number of counts per pixel in a projection the parameters of image reconstruction, particularly the cut-off frequency fc of the Butterworth filter, should be changed. Additionally, an attenuation correction with coefficient c=0.12 cm-1 and interpolation with matrix size equal 7x7 should be applied.

99Tcm-sestamibi tomoscintigraphy at rest and after nitrate administration in predicting wall motion recovery after revascularization.

To evaluate whether nitroglycerin administered before the injection of sestamibi improves the detection of viable but hypoperfused myocardium, 41 post-infarction patients with left ventricular dysfunction underwent echocardiography and SPET at rest and after nitrate administration. In 25 revascularized patients, perfusion at rest and contractility were assessed 3-4 months after coronary artery bypass grafting. Perfusion (PI) and wall motion indices (WMI) were calculated for each revascularized area. There was a strong correlation between contractility and perfusion defect (r = 0.58, P < 0.0001). Nitrates significantly reduced the number of perfusion defects in hypokinetic (delta PI = 0.25 +/- 0.66) and akinetic (delta PI = 0.32 +/- 0.62), but not in dyskinetic (delta PI = 0.08 +/- 0.62), segments. Twenty-five revascularized patients had 110 asynergic segments and 136 segments with a resting perfusion defect. Function improved in 42% and perfusion in 64% of segments after surgery. Viable segments had a lower PI at rest (2.78 +/- 1.38 vs 3.86 +/- 1.29, P < 0.001) and a lower WMI (2.46 +/- 0.50 vs 2.79 +/- 0.59, P = 0.002). Nitrates reduced the number of perfusion defects slightly more in viable than non-viable segments (delta PI = 0.58 +/- 0.89 vs 0.30 +/- 0.46, P = 0.06). Contractility and perfusion at rest were the most important predictors of functional recovery. The sensitivity and specificity in predicting contractile improvement were 74% and 64% for resting SPET respectively, and 80% and 50% for nitrate SPET respectively. Nitrate administration significantly reduces perfusion defects in asynergic regions; however, its usefulness in predicting contractile recovery may be limited owing to its low specificity. Contractility and sestamibi uptake at rest were the strongest predictors of post-operative wall motion improvement.

Use of 99Tcm-MIBI scintigraphy in the evaluation of perfusion improvement after myocardial revascularization with the use of the left internal thoracic artery.

In spite of successful revascularization, in a significant group of patients myocardial ischaemia is present after surgery. The final effect of surgery depends on preoperative left ventricular function, initial coronary artery status, completeness of revascularization, the use of arterial or venous grafts, and many other factors. The aim of our 99Tcm-MIBI scintigraphy study was to examine the improvement of perfusion in the left anterior descending artery (LAD) vascular territory after revascularization with the use of the left internal thoracic artery (LITA), with respect to the LAD diameter and use of additional venous graft to diagonal artery. The study group consisted of 45 subjects (42 male, three female) aged 34-68 years (mean age 50.9+/-8.3 years) recruited from patients in whom LITA was grafted into LAD. The operation and postoperative period was uneventful in all patients. Two weeks before, and 3-4 months after surgery, dipyridamole-rest sestamibi SPECT were performed. The revascularization significantly improved both stress (deltaPI = 0.77+/-0.66; P < 0.001) and rest (deltaPI = 0.32+/-0.60; P < 0.001) perfusion of the LAD territory. The improvement was slightly better in patients who received two grafts (deltaPI = 1.42+/-0.91) for the LAD territory in comparison to the group revascularized only with LITA (deltaPI = 0.80+/-0.69; P = patients who received an arterial bypass to the LAD artery the perfusion was abnormal in all eight patients after anterior myocardial infarction and in 39% of patients without a history of infarction. The perfusion improvement was the best when the diameter of LAD was > or = 1.5 mm (deltaPI = 0.88+/-0.95). The independent predictors of perfusion improvement were the number of segments with reversible perfusion defect within the revascularized area (beta = 0.84, P < 0.001), the diameter of revascularized artery (beta = 0.17, P = 0.03) and the presence of pathological Q wave at preoperative ECG (beta = -0.20, P = 0.02). We conclude that the degree of perfusion improvement in the LAD territory after revascularization with the use of LITA depends on the diameter of bypassed coronary artery, completeness of revascularization and the reversibility of preoperative perfusion defect.

A comparison of bone scans in uremic patients treated with intermittent peritoneal dialysis or hemodialysis.

The aim of the study was a comparative analysis of bone scans in uremic patients treated with intermittent peritoneal dialysis (IPD) or hemodialysis (HD). Bone scintigraphy was performed using technetium Tc 99m etidronate (EHDP) in 28 uremics (age 46.0 +/- 13.5 years, x +/- SD) on IPD for 3.1 +/- 3.0 months and 28 uremics (age 43.5 +/- 11.6 years) on HD for 47.3 +/- 33.9 months. Serum c terminal parathormone (cPTH) exceeded 5.3 +/- 3.3 and 6.8 +/- 3.5 times the upper normal limit of 1.4 ng/mL in IPD and HD patients, respectively. Despite significant differences in dialysis treatment duration in IPD and HD patients, an increased Tc 99m EHDP uptake in bones was shown with similar frequency, when all the groups were compared. However, in the group of patients with serum cPTH exceeding four times the upper normal limit (n = 30) or in the age group less than 45 years old (n = 26), a greater marker uptake was observed in HD patients. Significant differences (p < 0.05) were shown in the cranial vault: 33% of HD patients (n = 18) with higher cPTH and 47% of those less than 45 years old (n = 15) revealed an increased marker uptake, whereas it was not observed in any IPD patient. When scans of HD patients dialyzed less than (n = 11) and more than (n = 17) 30 months were compared, a significantly higher appearance of increased marker uptake was shown in cranial vault (41% vs 0%, p < 0.02) and in sacral bone (82% vs 36%, p < 0.02) in patients with longer dialysis. The latter group of HD patients also showed an increased marker uptake in cranial vault compared to the entire group of PD patients (41% vs 7%, p < 0.01). Our studies suggest that bone scan changes, indicating secondary hyperparathyroidism, progress significantly with prolongation of dialysis treatment, especially in patients with higher cPTH levels of younger age.

Cytological analysis of the urn cell complex of Sipunculus nudus before and after serum-induced secretion.

This study analyzes the cytology of the urn cell complex (UCC) of Sipunculus nudus, an invertebrate cell model for humorally regulated mucus secretion. An unstimulated UCC is composed of a vesicle cell and a ciliated cell joined together by desmosomes. Another cell population (third-type cells) is frequently associated with ciliated cells. Vesicle cells are thin, have few mitochondria or lipid droplets, and enclose a bubble-like cavity containing microfibrillar material. Ciliated cells contain several rows of cilia that are anchored by prominent rootlets and propel UCCs forward. Five to six concentric bundles of microfilaments are distributed along the outer convexity of ciliated cells and may have a role in the plasticity of the UCC. Many fibrillar deposits that lack a demonstrable limiting membrane are distributed around intracytoplasmic vacuoles facing the mouth-like opening of the UCC. These deposits are reactive to periodic acid-Schiff and resistant to diastase. After stimulation with serum, they appear to migrate through the ciliated cell's plasma membrane, contributing to the formation of a secretory tail. Discharge of secretory material is not observed in third-type cells, which instead contain lysosome-like granules and autophagic-like vacuoles and become displaced distalward by the emerging tail of the UCC. This study indicates that formation and elongation of the UCC secretory tail are functions of ciliated cells.

Effect of supplemental pig milk replacer on litter performance: seasonal variation in response.

The objective of this study was to determine the effect of supplemental milk replacer on sow and litter performance. The study was conducted in 12 farrowing groups (171 litters) over a 3.5-yr period (October 1990 to April 1994). Commercial milk replacer was prepared fresh daily (150 g/L) and offered with ad libitum access in the farrowing crates within 24 h of parturition and was continued through weaning (d 21). Average pig weight (control, 5.5 kg/pig; supplemented, 6.4 kg/pig; P < .001) and total litter weight (control, 52.2 kg/litter; supplemented, 60.9 kg/litter; P < .001) at weaning were greater for litters receiving supplemental milk replacer. There was no effect (P > .2) of supplemental milk replacer on feed intake, backfat thickness, or body weight loss in the sow. Consumption of milk replacer varied greatly among litters. A portion of this variation in intake was accounted for by differences in ambient temperature among farrowing groups. Average milk replacer intakes (liters per pig) from birth to d 21 were 2.5 L/pig (.375 kg dry matter) and 9.9 L/pig (1.49 kg dry matter) for pigs born during the cool and warm seasons, respectively (P < .001). The weaning weight advantage conferred by milk replacer was most evident during the warmer months. Sow feed intakes averaged 5.8 and 3.9 kg/d over the same periods (P < .001). These results demonstrate the advantage of milk replacer on weaning weight and indicate that the greatest benefit from the supplement is during the warmer months when sow feed intake and subsequent milk production are lower.