Effects of cyclosporins and transforming growth factor β1 on thyroid hormone action in cultured fetal rat limb bones

Summary To study the mechanism of action of thyroid hormones on bone, we examined the effects of immunosuppresive and nonimmunosuppressive cyclosporins, as well as of transforming growth factor ₁ (TGF₁), 17-estradiol (E₂), and dihydroxytestosterone (DHT) on thyroxine (T₄)-and triiodothyronine (T₃)-stimulated bone resorption in fetal rat limb bones. The immunosuppressive cyclosporins A (CsA) and G (CsG) inhibited thyroid hormone (T₄+T₃)-stimulated resorption and -glucuronidase release into the culture medium, whereas the weak or nonimmunosuppressive cyclosporins D (CsD) and H (CsH) did not show this effect. Increasing the medium calcium concentration reduced the ability of T₄ to stimulate ⁴⁵Ca release, while not significantly affecting the response to CsA. TGF₁ elicited a biphasic effect when administered together with T₄. During the first 3 days of culture, TGF₁ elicited a small, nonsignificant decrease in released ⁴⁵Ca; during a subsequent 3 days of culture, it enhanced T₄-stimulated bone resorption significantly. These effects differed from those of TGF₁ on parathormone-stimulated resorption. E₂ and DHT did not influence the action of T₄ on bone tissue. These results suggest that the mechanism of action of thyroid hormones on bone may involve immune factors, as well.     

Beneficial effect of thyroxin in the treatment of ischemic acute renal failure

To evaluate the effect of thyroxin (T₄) on recovery from ischemic acute renal failure, rats were treated with T₄ (10 or 20 g/100 g body wt.) or normal saline (NS) either immediately prior to, immediately after or 24 h after 45 min of renal ischemia. Animals given T₄ prior to ischemia had no significant increase in Inulin clearance (C_in) (377±40 l/min per 100 g body wt.) as compared with saline-treated ischemic controls (306±54). In contrast, animals treated immediately after ischemia with either dose of T₄ demonstrated significantly better kidney function (C_in 515±59 l/min per 100 g body wt., U_osm 842±88 mosmol/kg, FE_Na 0.52%±0.12% and C_in 543±71, U_osm 939±103, FE_Na 0.48±0.12, for 10 and 20 g/100 g body wt., respectively). Moreover, the improvement in renal function was sustained and C_in was significantly better at day 3 (748±70) and day 7 (990±75) compared with saline controls (560±30 and 732±45, respectively). Animals which received T₄ 24 h after ischemia showed significantly higher C_in when compared with ischemic controls. To assess the impact of T₄ on recovery of renal ATP,³¹P-NMR was used. T₄-treated rats demonstrated 90%±5% recovery of renal ATP by 120 min of reflow, whereas NS animals had only 64%±1%. In addition, cellular morphology was better preserved in T₄ animals. These data indicate that animals treated postischemically with T₄ showed accelerated and sustained recovery from acute renal failure. This beneficial effect appears to be related to cellular mechanisms which are essential for the restoration of sublethally injured cells.     

A Prostacyclin Analogue,OP-41483α-CD,Restores the Ability of a β<Subscript>2</Subscript>-Adrenergic Agonist to Stimulate Alveolar Fluid Clearance in Rats

Purpose. It is not yet known whether a prostacyclin analogue can affect alveolar fluid clearance. According to recent studies, high-dose (10^–3M) terbutaline, a ₂-adrenergic agonist, failed to increase alveolar fluid clearance. Therefore, we examined the effects of OP-41483-CD, a prostacyclin analogue, on alveolar fluid clearance in the presence of high-dose terbutaline in rats.Methods. Albumin solution containing Evans blue dye and various drugs was instilled into the alveolar airspaces of isolated rat lungs, which were then inflated with 100% oxygen at an airway pressure of 8cmH₂O. Alveolar fluid clearance was measured by the progressive increase in dye concentrations over 1h.Results. Although 10^–5 and 10^–4M terbutaline increased alveolar fluid clearance, 10^–3M terbutaline did not. OP-41483-CD restored the ability of 10^–3M terbutaline to stimulate alveolar fluid clearance. The effect of OP-41483-CD was consistent with the effect of atenolol, a ₁-adrenergic antagonist. The effect of OP-41483-CD on alveolar fluid clearance was unchanged in lungs inflated with nitrogen. Prostaglandin E (PGE)₁ and PGE₂ analogues had similar effects to OP-41483-CD on alveolar fluid clearance.Conclusion. These results indicate that a prostacyclin analogue restores the ability of high-dose terbutaline to stimulate alveolar fluid clearance.     

pQCT bone strength index may serve as a better predictor than bone mineral density for long bone breaking strength

Bone mineral density (BMD) is commonly used to predict osteoporotic fracture risk without considering the geometry of the bone. However, geometric parameters are also important in determination of bone strength. An index including both material and geometric properties may be therefore more relevant in prediction of fracture risk. We studied the correlation between parameters measured by noninvasive peripheral quantitative computed tomography (pQCT) and bone bending strength of the diaphysis of 45 fresh goat humeri and 27 femora. Multislice pQCT was used for measuring volumetric diaphyseal cortical BMD, total BMD, diaphyseal and cortical cross-sectional area (CSA), and cross-sectional moment of inertia (CSMI) and their derived bone strength indices (BSIs), including BSI_CSMI (cortical BMD × CSMI) and BSI_CSA (cortical BMD × cortical CSA). Conventional dual-energy absorptiometry (DXA) was also conducted to measure areal BMD of diaphysis for comparison. Ultimate fracture load was obtained via three-point bending test. Results showed that for femora, fracture load was correlated better with BSI_CSA (r = 0.697, P 0.001) than cortical BMD (r = 0.304, P 0.05) and total BMD (r = 0.387, P 0.05) measured using pQCT and areal BMD (r = 0.612, P 0.001) measured using DXA. For humeri, fracture load was also correlated with BSI_CSA (r = 0.579, P 0.001) but not with other pQCT parameters including cortical BMD and total BMD (r = 0.282 and 0.305, respectively; P 0.05, both). The best correlation was found with areal BMD measured by DXA (r = 0.760, P 0.001). In conclusion, pQCT noninvasive BSI_CSA derived from cortical BMD (material) and its cortical CSA (bone geometry or distribution) may serve as an important noninvasive index for predicting long bone bending strength. The bending strength was also predicted by bone mass (areal BMD) measured by DXA, an integration of bone mineral and geometry. Further clinical studies are needed to validate the predictive value of BSI in long bone osteoporotic fracture.     

Altered Integrin Expression and the Malignant Phenotype: The Contribution of Multiple Integrated Integrin Receptors

The integrins are a family of cell surfaceadhesion receptors that mediate adhesion to eithercomponents of the extracellular matrix or to othercells. The ₁ family of integrinsrepresent the major class of cell substrate receptors withspecificities primarily for collagens, laminins, andfibronectins. The role of the integrin family of cellsurface adhesion receptors in normal mammary glandmorphogenesis and the contributions of altered integrinreceptor expression to the invasive and metastaticphenotype have been the primary focus of our lab, aswell as a number of other laboratories. The_{2 1} integrin is expressed at high levels by normaldifferentiated epithelial cells including those of thenormal breast. Using breast cancer as a model, weevaluated changes in integrin expression in malignancy. We and other investigators made the keyobservation that _{2 1}integrin expression is decreased in adenocarcinoma ofthe breast in a manner that correlates with the stage ofdifferentiation. Studies of other adenocarcinomas have yielded similarresults. When the _{2 1}integrin was reexpressed in a poorly differentiatedmammary carcinoma that expressed no detectable₂ integrin subunit, a dramatic reversion of malignant phenotype to adifferentiated epithelial phenotype was observed,indicating a critical role for₂₁ expression inmammary gland differentiation. Other laboratories using monoclonal antibodies to competitivelyinhibit _{2 1} integrinadhesion or oncogenic transformation using c-erb2 haveconfirmed the important role of that ₂₁ integrin in mammary gland morphogenesis. Re-expression of the_{2 1} integrin alsoresults in upregulation of both the ₆and ₄ integrin subunits. To determinethe contribution of enhanced ₆ and₄ integrin expression to the abrogation of the malignantphenotype by _{2 1}integrin expression, we have now separately re-expressedthe human ₆ or ₄integrin subunit in the breast cancer model.     

Urinary excretion of adenosine deaminase binding protein in neonates treated with tobramycin

The potential tubulotoxicity of tobramycin and cefotaxim were assessed in neonates by measuring the urinary level of adenosine deaminase binding protein (ABP) and urinary ₁-microglobulin and ₂-microglobulin. In a prospective study, 33 neonates who received tobramycin and cefotaxim for suspected neonatal sepsis were compared with 48 untreated newborns during the first 10 days of life. The urinary concentrations of ABP and its excretion rates, corrected for body weight and body surface area, were significantly increased from the 1st day of treatment. Urinary ₁-microglobulin and ₂-microglobulin were not elevated under tobramycin and cefotaxim during the first 2 days of treatment. We conclude that ABP may be a sensitive marker for the detection of proximal renal tubular injury during tobramycin and cefotaxim treatments of neonates. The increase in urinary ABP which occurs before an elevation of urinary ₁-microglobulin and ₂-microglobulin may reflect earlier structural than functional alterations. However, since none of the treated infants had signs of electrolyte disorders or glomerular dysfunction, the clinical relevance of ABP measurement should be reevaluated.     

Tubular PAH transport capacity in human kidney tissue and in renal cell carcinoma: correlation with various clinical and morphological parameters of the tumor

In vitro accumulation ofp-aminohippurate (PAH) was investigated in intact human renal cortical slices of normal kidney tissue and in tissue slices of renal cell carcinoma (RCC). The technique used was established in preliminary experiments on rat kidney tissue slices. In principle, the accumulation capacity is comparable in renal tissue slices of both species (slice to medium accumulation ratios between 4 and 8). In man sex differences in accumulation capacity do not exist. But, as shown in detail for rats, accumulation capacity drops with age. Tissue slices of RCC are unable to accumulate PAH actively; slice to medium ratio reaches about 1 and indicates passive PAH uptake only. Surprisingly, in tumors of stage pTl PAH uptake is lowest, perhaps as a sign of PAH transport out of the cells. There is no difference between peripheral and central parts of RCC. Age and sex are without influence on PAH uptake in RCC tissue slices. Interestingly, the accumulation capacity of intact tissue of kidneys infested with RCC also depends on the severity of the tumor (stage, diameter), but not on grading and formation of metastases.     

Clinical trial of risedronate in Japanese volunteers: single and multiple oral dose studies

The tolerability and pharmacokinetics of risedronate after a single oral administration and during multiple oral administrations were examined in healthy adult male volunteers. In the single dose study, the dose was increased gradually from 1mg to 2.5, 5, 10, or 20mg. Subsequently, risedronate was given by multiple administration, 5mg per dosing, once daily, for 7 days. The observed adverse events, whose causality was possibly related or unknown, included headache, diarrhea, increased body temperature, increased CK-BB, and increased urinary ₂-microglobulin excretion rate. However, none of these adverse events was clinically significant. The results thus showed that risedronate was well tolerated when delivered as a single administration of up to 20mg or as a multiple administration of up to 5mg/day. In the multiple dose study, changes in urinary deoxypyridinoline suggested the bone antiresorptive activity of risedronate. In the single dose study, AUC and C_max, after the administration of risedronate at 1, 2.5, 5, 10, and 20mg, increased dose dependently, and the T_max, t_1/2, and urinary excretion rates were nearly constant. Therefore, the pharmacokinetic profile of risedronate was considered to show linearity in a dosage range of up to 20mg. Furthermore, the results obtained in the multiple administration study indicated that the plasma concentrations of risedronate reached a steady state on day 4 of administration. The plasma concentrations of risedronate after the administration of 2.5mg risedronate to the Japanese population were nearly comparable to the serum concentrations after the administration of 5mg risedronate to the United Kingdom study population.     

Expression of Transforming Growth Factor Betas and Their Signaling Receptors in Stone-containing Intrahepatic Bile Ducts and Cholangiocarcinoma

Transforming growth factor betas (TGF-s) are multifunctional polypeptides that either inhibit or stimulate cell proliferation. They mediate their functions through their signaling receptors. Clinically, hepatolithiasis has been regarded as a risk factor for cholangiocarcinoma. The aim of this study was to examine the expression of TGF-s and their receptors in stone-containing intrahepatic bile ducts (IHD) and cholangiocarcinoma and try to predict whether hepatolithiasis has a predisposition to development of cholangiocarcinoma. Twenty-eight surgically resected specimens of stone-containing IHD and 15 specimens of cholangiocarcinoma were subjects for this study. Immunohistochemical analysis was done on three TGF-s and their signaling receptors to check their expression in non-neoplastic and neoplastic bile ducts. No immunoreactivity of TGF-₁ was found in any specimens. The overexpression of TGF-₂ and TGF-₃ was found in both hepatolithiasis (93%–100%) and cholangiocarcinoma (80%) at levels significantly higher than those of normal controls (10%–20%) (p < 0.001). The immunoreactivity of type I receptor (TRI) and type II receptor (TRII) also showed increased expression in stone-containing IHD, whereas TRII was absent in cholangiocarcinoma. We conclude that the overexpression of TGF-₂ and TGF-₃ and the absence of TRII in cholangiocarcinoma could lead to enhanced tumor cell proliferation. At the same time, the overexpression of TGF-s and their receptors in stone-containing IHD could suggest a close relationship between hepatolithiasis and cholangiocarcinoma.     

Effects of cyclosporin A on rat osteoblasts (ROS 17/2.8 cells) in vitro

Summary The effects of the immunosuppressive drug cyclosporin A (CsA) were evaluated on ROS 17/2.8 cells in vitro. ROS cells were treated with CsA (0, 0.5, 1.0, 5.0 g/ml) for 3 days with and without bovine parathyroid hormone (bPTH) (1–34) 10 nM. CsA at 0.5, 1.0, 5.0 g/ml without PTH and at 5.0 g/ml in the presence of PTH significantly inhibited proliferation, as determined by a tetrazolium colorimetric assay. In addition, ROS cell number was significantly reduced at 3 and 4 days with CsA (5.0 g/ml) without affecting cell viability. Incorporation of [³H]-thymidine into DNA was significantly reduced by 3.0 and 5.0 g/ml CsA after 12 and 24 hours exposure. Basal and 1,25-dihydroxyvitamin D₃-stimulated alkaline phosphatase levels in confluent ROS cells were reduced (P<0.05) with CsA (1.0 and 3.0 g/ml). Pretreatment of ROS 17/2.8 cells with CsA did not alter PTH-stimulated cAMP levels or [¹²⁵I]-PTHrP binding to ROS cells. CsA treatment of ROS 17/2.8 cells induced a spindle-shaped appearance with loss of attachment in confluent cultures. When ROS cells were cultured in CsA-containing media, cellular attachment at 6 and 12 hours was reduced (P<0.05) compared with untreated ROS cells. These findings indicate that CsA was capable of inhibiting proliferation, cell number, mitogenesis, alkaline phosphatase levels, and cell attachment of ROS cells without affecting PTH binding or cAMP levels. This direct effect of CsA on osteoblasts may be important in changes of bone remodeling observed in CsA-treated humans and animals.     

Comparison of anesthetic effects of epidural and intravenous administration of buprenorphine during operation

Thirty six patients were received epidural anesthesia with or without buprenorphine (BPN) during upper abdominal surgery. They were divided into three groups of 12 patients as follows; G-I received 20ml of 1% lidocaine epidurally, G-II received 20ml of 1% lidocaine epidurally and 0.6mg BPN intravenously, G-III received 20ml of 1% lidocaine with 0.6mg BPN epidurally. Additional 5ml of 1% lidocaine was given to any patient if systolic blood pressure or heart rate increased 10% compared to control value. Trachea was intubated following anesthetic induction with thiopental. The lungs were ventilated with a mixture of N₂O/O₂ (33%) and pancuronium was used for muscle relaxation. The total required doses of lidocaine in G-II and G-III were decreased 60% compared to control group (G-I) (P 0.05). The mean period of time until the first administration of pentazocine for postoperative pain was 13 ± 10hr (mean ± SD) in G-II and 19 ± 24hr in G-III compared to 5 ± 4hr in G-I (P 0.001). The dose of the administration of pentazocine that was required for pain relief during the first 48 postoperative hr in G-III was 54 ± 10mg (mean ± SD) compared to 150 ± 21mg in G-I (P 0.02) and 106 ± 28mg in G-II (P 0.05). Recovery from anesthesia in G-III was more rapid than that in G-I (P 0.05). The Pa_{CO 2} values in G-II and G-III increased 15% compared to control group at about 4hr and 8hr after administration of BPN, but any clinical treatment was not needed for them. Nonrespiratory side effects, e.g., nausea, vomiting, fatigue and headache, were comparably common in all groups. Mild hematuria associated with acute hypotension occurred in two patients in G-II (17%) immediately after the intravenous injection of 0.6mg of BPN. The results showed that 0.6mg of BPN given epidurally demonstrated better anesthetic and more potent postoperative analgesic effects and lesser side effects than 0.6mg of BPN given intravenously in patients undergoing upper abdominal surgery.(Yonemura E, Fukushima K.: Comparison of anesthetic effects of epidural and intravenous administration of buprenorphine during operation. J Anesth 4: 242–248, 1990)     

Interim evidence of the renoprotective effect of the angiotensin II receptor antagonist losartan versus the calcium channel blocker amlodipine in patients with chronic kidney disease and hypertension: a report of the Japanese Losartan Therapy Intended for Global Renal Protection in Hypertensive Patients (JLIGHT) Study

Background. Insufficiency of renal function and high blood pressure influence each other and eventually result in life-threatening endstage renal disease. It has been proposed that proteinuria per se is a determinant of the progression of chronic kidney disease (CKD). The therapeutic strategy for patients with proteinuric CKD and hypertension should therefore be targeted with a view not merely toward blood pressure reduction but also toward renoprotection. Methods. We examined the effect of the angiotensin (AT)₁ receptor antagonist losartan and the calcium channel blocker amlodipine, throughout a period of 12 months, on reduction of blood pressure and renoprotection. This was done by assessing amounts of urinary protein excretion, serum creatinine (SCr), and creatinine clearance (CCr) in patients with hypertension (systolic blood pressure [SBP] 140mmHg or diastolic blood pressure [DBP] 90mmHg) and CKD (male, body weight [BW] 60kg: 1.5 SCr < 3.0mg/dl; female or male BW < 60kg: 1.3 SCr < 3.0mg/dl), manifesting proteinuria of 0.5g or more/day. Losartan was administered once daily at doses of 25 to 100mg/day, and amlodipine was given once daily at 2.5 to 5mg/day. No antihypertensive combination therapy was allowed during the first 3-month period. Results. A 3-month interim analysis revealed that, despite there being no difference in blood pressure between the two groups, there was a significant reduction in 24-h urinary protein excretion in the losartan group (n = 43), but there was no change in the amlodipine group (n = 43). Analysis of stratified subgroups with proteinuria of 2g or more/day and less than 2g/day showed that losartan lowered proteinuria by approximately 24% in both subgroups, while amlodipine lowered proteinuria by 10%, but only in the subgroup of less than 2g/day (NS). SCr and CCr did not change throughout the period of 3 months in either group. No severe or fatal adverse event was experienced in either group during the study period. Conclusions. Losartan appeared to be efficacious for renoprotection in patients with proteinuric CKD and hypertension, with the mechanism being independent of its antihypertensive action.     

Scanning electron microscopy-electron probe microanalysis study of the interface between apatite and wollastonite-containing glass-ceramic and rabbit tibia under load-bearing conditions after long-term implantation

Glass-ceramic implants containing oxy- and fluoroapatite [Ca₁₀(PO₄)₆(O, F₂)] and -wollastonite (CaSiO₃) were studied under load-bearing conditions in a segmental replacement model in the tibia of the rabbit. A 16-mm segment of the middle of the tibial shaft was resected at a point distal to the junction of the tibia and the fibula. The defect was replaced by a 15 mm-long hollow, cylindrical implant that was fixed by intramedullary nailing using Kirschner wire. The implants were 9 mm in diameter and 15 mm long bearing a central hole 3.05 mm in diameter. The rabbits used were killed 6 months, 1 year, 18 months, and 2 years after implantation. The interface between the bone and the glass-ceramic was investigated by scanning electron microscopy-electron-probe microanalysis (SEM-EPMA).None of the glass-ceramic implants broke, and the glass-ceramic had bonded directly to the bone tissue without any intervening soft tissue. A calcium-phosphorus layer (Ca-P layer) was observed at the glass-ceramic/bone interface. This layer was 30–100 m thick at 6 months after implantation, 60–110 m thick at 1 year after implantation, 80–200 m thick at 18 months, and 120–350 m thick at 2 years. At the lateral surface of the glass-ceramic uncovered by the bone, the calcium-phosphorus layer was 50–80 m thick at 6 months after implantation, 250–450 m thick at 1 year, 300 400 m thick at 18 months, and 300 m thick at 2 years. The thickness of the calcium-phosphorus layer increased moderately after long-term implantation. However, it was difficult to estimate the rate of increase in the thickness of calciumphosphorus layer.     

Dose-finding study of intravenous midazolam for sedation and amnesia during spinal anesthesia in patients premedicated with intramuscular midazolam

Purpose We investigated the effective and safe dose of intravenous midazolam for sedation and amnesia during spinal anesthesia in patients premedicated with intramuscular midazolam.Methods One hundred and eighty patients aged 20–50 years scheduled for spinal anesthesia received midazolam 0.06mg·kg^–1 and atropine 0.01mg·kg^–1 intramuscularly 15min before entering the operating room. Spinal anesthesia was performed with 0.5% hyperbaric tetracaine. Five minutes after starting surgery, midazolam 0 (control group), 0.01, 0.02, 0.03, 0.04, or 0.05mg·kg^–1 was intravenously administered (30 patients each). Blood pressure, heart rate, respiratory rate, percutaneous oxygen saturation (S_{p O 2}), verbal response, eyelash reflex, and involuntary body movement were measured every 5min for 30min. Memory during surgery was also investigated.Results The number of the patients with loss of verbal response, with loss of eyelash reflex, and with no memory during surgery were significantly larger in the groups receiving midazolam 0.03mg·kg^–1, 0.04mg·kg^–1, and 0.02mg·kg^–1, respectively. The decrease in blood pressure or increase in respiratory rate with decrease in S_{p O 2} was significantly larger in the groups receiving midazolam 0.03mg·kg^–1 or 0.05mg·kg^–1, respectively.Conclusion For sedation and amnesia of the patients aged 20–50 years in spinal anesthesia with about 1h duration receiving intramuscular midazolam 0.06mg·kg^–1 as a premedication, intravenous midazolam 0.02mg·kg^–1 might be effective and safe.     

To-and-fro extracorporeal lung assist (ECLA) through a single catheter — in premature goats as an experimental model of infant respiratory insufficiency

A new to-and-fro V-V bypass extracorporeal lung assist (ECLA) through a single catheter as a blood access was investigated for its efficacy on six premature goats delivered by Cesarean section at a gestational age of 118 139 days as an experimental model of infant respiratory insufficiency, then applied to a human premature infant suffering from life threatening barotrauma that had developed from mechanical pulmonary ventilation. The extracorporeal bypass flow and the gas flow to the artificial membrane lung were controlled to keep Pa_{O 2} above 40mmHg and Pa_{CO 2} within normal limits. The neonates own lungs were treated with a continuous positive airway pressure of 5 12cmH₂O, apneic oxygenation or IMV. Two goats weighing 1250g and 700g died 2 2.5 hours after birth from severe circulatory distress. However, the other four neonates which were heavier than 2000g, were successfully weaned from ECLA, and three of these could be weaned from mechanical ventilation as well. A human infant also survived and was weaned from ECLA on the third day.(Tanoue T, Terasaki H, Sadanaga M et al.: To-and-fro extracorporeal lung assist (ECLA) through a single catheter-in premature goats as an experimental model of infant respiratory insufficiency. J Anesth 2: 124–132, 1988)     

Effects of transforming growth factor-β1 on formation and activation of osteoclasts

Transforming growth factor-₁ (TGF-₁) has biological functions in various types of cells. However, its roles in the regulation of osteoclast formation and function are unclear. To examine them, we employed a culture system in which unfractionated cells obtained from long bones of 13-day-old mice were cultured on a dentine slice. We found that TGF-₁ has a potent inhibitory effect on osteoclastic bone resorption at a dose of 0.2–5 ng/ml. By electron microscopy the osteoclasts appeared to have fewer mitochondria and ruffled borders than those in control cultures. But in the presence of 1,25-dihydroxyvitamin D₃, [1,25-(OH)₂D₃], TGF-₁ at a dose of 0.2–1 ng/ml stimulated the formation of osteoclasts from unfractionated bone cell cultures in which preexistent osteoclasts had degenerated. Thus, using stromal cell-free he-mopoietic blast cells, we examined the direct action of TGF-₁ on osteoclast precursors. Although TGF-₁ inhibited tartrate-resistant acid phosphatase-positive (TRAP) multinucleate cell (MNC) formation induced by 1,25-(OH)₂D₃, the conditioned medium (CM) of TGF-₁-treated MC3T3-E1 cells stimulated such formation. These results suggest that TGF-₁ inhibits osteoclastic bone resorption but stimulates osteoclast formation via the action of factor(s) produced by TGF-₁-treated osteoblasts in the presence of 1,25-(OH)₂D₃.     

Mineral concentration gradients in rat femoral diaphyses measured by X-ray microtomography

The bone mineral concentrations of five rat femora were measured as a function of distance from the distal metaphysis by quantitative X-ray microtomography (XMT) at a resolution of approximately 23×23×15 m³. Assuming the mineral phase of bone to be hydroxyapatite, Ca₁₀ (PO₄)₆ (OH)₂, the mean cortical mineral concentration (C_M) per transverse section was found to range from 1.33 to 1.47 g cm^-3. Detectable variations in the bone mineral concentration between sections of femora from different animals could not be attributed to the age when the particular animal was sacrificed. An increase in C_M with distance, L, from the distal growth plate was observed and a saturating exponential equation, C_M = a – be ^L, was used to describe the changes. Each section of bone tissue was considered as a population of elementary volumes of bone (EVB) and L was related to the age of the EVB (T_EVB). A simple model for the mineralization process of an EVB was then proposed Each newly formed EVB accumulated mineral rapidly to give an initial mineral concentration of 1.3 g cm^-3 (parameter a-b). Their mineral concentrations then increased asymptotically to 1.5 g cm^-3 (parameter a) with a time constant of 330 days. This slow maturation process is attributed to Ostwald ripening of the bone crystals with further crystal growth using ions from the extracellular fluid.     

Effects of 1α-hydroxyvitamin D3 on serum calcium and immunoreactive parathyroid hormone in patients with chronic renal insufficiency

Six patients with chronic renal failure on regular dialysis treatment were given low doses (0.5–1.0 g/day) of 1-hydroxyvitamin D₃, monitoring the serum calcium, inorganic phosphate, immunoreactive parathyroid hormone concentration (IPTH) and alkaline phosphatase activity. The serum calcium rose in all patients after 7 days' treatment, in some subjects to hypercalcemic range; this effect persisted 6–14 days after withdrawal of 1-hydroxyvitamin D₃. The elevated serum IPTH rose in the first days of treatment, but later decreased to normal values. It is suggested that active vitamin D metabolites are necessary for normal response of parathyroid glands to variation in serum calcium. Low-dose 1-hydroxyvitamin D₃ treatment appears to be a promising method of correcting hypocalcemia and secondary hyperparathyroidism in chronic renal failure. Careful control of serum calcium is necessary, as hypercalcemia may occur even after minute doses of 1-hydroxyvitamin D₃.     

Zur Bedeutung von β-hCG im serum als tumormarker fur das magenkarzinom

Zusammenfassung Einleitung: Nach neueren Untersuchungen ist davon auszugehen, daß bei des Hälfte von Patienten mit einem Magenkarzinom -hCG-positive Zellen im Tumor immunhistochemisch gefunden werden können. Ziel war daher, systematisch zu untersuchen, inwieweit -hCG-immunreaktive Magenkarzinome von einem Anstieg des Serum--hCG begleitet werden and dieses damit als Verlaufsparameter zur Verfügung steht. Methode: Bei 54 Patienten mit einem Magenkarzinom wurde zur immunhistochemischen Darstellung ein gegen -hCG gerichteter monoklonaler Antikörper (Fa. Sigma, 1:100) im APAAP-System verwendet. Die Auswertung wurde nach positiver and negatives Reaktion graduiert. Parallel wurde im Serum des Patienten -hCG präoperativ mit einem Enzymimmunoassay (MEIA, Fa. Abbot) bestimmt. Tumor-stadium, Grading and Tumor-lokalisation werden in die Auswertung mit einbezogen. Ergebnisse: Es wird bestätigt, daß 41% (22 von 54) des Karzinome, unabhängig von ihrer Lokalisation im Magen, eine positive immunhistochemische Reaktion gegen -hCG auslösen. Es zeigte sich in Abhängigkeit vom Tumorstadium eine positive -hCG-Immunreaktivität in 27% (6 von 22) des Tumoren ohne Lymphknoten- and Fernmetastasierung (T_1–4 N₀ M₀), in 54% (7 von 13) des Tumoren mit Lymphknotenaber ohne Fernmetastasen (T_1–4 N₁ M₀) und in 47% (9 von 35) des Tumoren mit Fernmetastasierung. Schlecht differenzierte Tumoren (G3–4) waren zu 42% (15 von 36) und gut differenzierte Tumoren (G_1–2) nur zu 39% (7 von 18) positiv. Aber lediglich bei einer Patientin war der -hCG-Spiegel im Serum erhöht. Zusammenfassung: Immunhistochemisch -hCG-positive Magenkarzinome werden vermehrt bei fortgeschrittenem Tumorstadium und Schlecht differenzierten Karzinomen gefunden. Diese Kar zinome scheinen aber nicht in ausreichender Menge -hCG ins Serum abzugeben, was zu serologisch meßbar erhöh-ten Werten führt. -hCG im Serum kann daher nicht als Prognosefaktor bzw. zur Verlaufskontrolle herangezogen werden. Abzuwarten bleibt, inwieweit die -hCG-Expression von Tumorzellen u. U. Einfluß auf die Propose der Patienten besitzt.

---

Significance of -hCG in the serum as a tumour marker for gastric cancer

Introduction: Recent investigations indicate that in 50% of patients with gastric cancer, -hCG-posiitive cells can be found in the tumour by immunohistochemical investigations. The objective of this study was to investigate how often -hCG-immunoreactive gastric carcinomas were accompanied by an elevation in serum -hCG, that could have been used as a course control variable. Methods: In 54 patients with gastric carcinoma a monoclonal antibody directed against -hCG was used for immunohistochemical marking in the APAAP system. The evaluation was graded positive or negative. In parallel, serum -hCG was determined preoperatively using an enzyme immunoassay (MEIA). Tumour stage, grading and tumour locallization were determinants in the evaluation. Results: We found that 41% (22 of 54) of the carcinomas induced a :positive immunohistochemical response to -hCG, regardless of their location in the stomach. In relation to tumour stage, a positive -hCG immunoreactivity was apparent in 27% (6/22) of tumours without lymph node or distant metastases (TI -4N0M0), in 54% (7/13) of tumours with lymph node and without distant metastases (T1–4N1 M0) and in 47% (9/35) of tumours with distant metastases. Poorly differentiated tumours (G3–4) were positive in 42% (15/36) and well-differentiated tumors (G1–2) in 39% (7/18) of cases. In only 1 patient was the -hCG, level in serum elevated, however. Conclusions: -hCG-Positive gastric carcinomas are found more frequently in advanced tumour stages and poorly differentiated carcinomas. These carcinomas, however, seem not to excrete -hCG in sufficient amounts to produce measurable serum values. Therefore, -hCG cannot be used a prognostic factor or for course control. The relevance of -hCG expression of tumour cells to the patients' prognosis remains obscure.

     

242. Korrelation klinischer und biochemischer Befunde mit dem Schweregrad einer bakteriellen Peritonitis

Zusammenfassung Anhand von Verlaufsdaten 66 chirurgischer Patienten mit einer bakteriologisch gesicherten Peritonitis sollten harte und weiche Kriterien zur Beurteilung des Schweregrades differenziert werden. Untersuchungskriterien: 1) regionale Ausbreitung, 2) Entwicklung eines Organod. Systemversagens, 3) Leukocytose/Thrombopenie, Körpertemperatur, 4) die Plasmamediatoren Endotoxin/Prostaglandin F₂ (PGF₂), 5) Anamnesedauer (Erstsymptom bis OP), 6) Anzahl erforderlicher Reoperationen und 7) Lebensalter. Zuzuordnende Schweregrade: Grad 1: überlebt, Grad 2: mit Komplikationen überlebt, Grad 3: nicht überlebt. Danach erweisen sich als harte Kriterien: 1) Lokalisation, 2) Anamnesedauer, 3) Leukocytose, 4) Endotoxin > 100 Eu/ml, PGF₂ > 500 pg/ml, 5) Körpertemperatur 38,5°C.