Serum bone sialoprotein as a marker of tumour burden and neoplastic bone involvement and as a prognostic factor in multiple myeloma

To test the potential of immunoreactive BSP, a non-collagenous bone matrix component, as a clinical guide in patients with plasma cell dyscrasias, serum BSP concentrations were measured in 62 patients with newly diagnosed multiple myeloma (MM) followed over a period of 4 years, in 46 patients with monoclonal gammopathy of undetermined significance (MGUS), in 71 patients with untreated benign vertebral osteoporosis (OPO), and in 139 healthy adults. Results were compared with clinical and laboratory data, including serum osteocalcin (OC), and urinary pyridinoline (PYD) and deoxypyridinoline (DPD) as markers of bone turnover. In MM, serum BSP, and urinary PYD and DPD were higher than in healthy controls and in MGUS or OPO (P< 0.001). BSP levels correlated with the bone marrow plasma cell content (r = 0.40, P< 0.001), and serum beta2-microglobulin (r = 0.31, P < 0.01). The differentiation of MM from healthy controls and from MGUS or OPO was highest for BSP. After chemotherapy, BSP reflected the response to treatment and correlated with the change in monoclonal protein (r = 0.55, P< 0.001). MM patients with normal baseline BSP levels survived longer than patients with initially elevated BSP values (P< 0.001, log rank test). Only serum monoclonal protein and BSP were independent predictors of survival. We conclude that in MM, BSP levels are associated with skeletal involvement and tumour cell burden. The quantification of serum BSP may be a non-invasive method for the diagnosis and follow-up, and may improve the prognostic value of conventional staging in MM.

Subarachnoid sufentanil for early postoperative pain management in orthopedic patients: a placebo-controlled, double-blind study using spinal microcatheters

BACKGROUND

Continuous spinal anesthesia is frequently used for intraoperative anesthesia but rarely for postoperative pain management. Because even small doses of local anesthetics can be associated with motor deficits, subarachnoid opioid injection may be an alternative.

METHODS

Eighty patients randomly received a subarachnoid injection of 10 microg sufentanil, 5 mg bupivacaine, 2.5 microg sufentanil plus 2.5 mg bupivacaine, or saline through 28-gauge spinal microcatheters for early postoperative pain relief after major lower-limb surgery (n = 20 in each group). Hemodynamic and respiratory parameters, pain scores, and motor function were monitored, and sufentanil concentrations in plasma and cerebrospinal fluid were measured. Ten additional patients received up to three repetitive injections of 10 microg sufentanil over 24 h.

RESULTS

All drugs provided excellent pain relief within 15 min after injection, lasting 128 +/- 61 min with sufentanil, 146 +/- 74 min with bupivacaine, and 167 +/- 78 min with the mixture. Patients receiving bupivacaine showed the highest cephalad extension of sensory block (median, T6) and the most intense motor block, whereas patients given only sufentanil had no motor deficit. The duration of analgesia was shorter after subsequent sufentanil injection (100-115 min) than after the first injection (198 +/- 70 min). Six of 50 patients with sufentanil experienced a short episode of respiratory depression within 30 min after the first injection. Cerebrospinal fluid concentrations of sufentanil peaked at 5 min after injection (183 +/- 167 ng/ml) but were at the level of detection in the plasma.

CONCLUSIONS

Sufentanil injected through microspinal catheters provided profound pain relief without impairing motor function when compared with bupivacaine. However, close monitoring remains mandatory in this setting.

Features of vestibuloocular reflex modulations induced by altered gravitational forces in tadpoles (Xenopus laevis)

In Xenopus laevis tadpoles, we studied the static vestibuloocular reflex (rVOR) in relation to modifications of the gravitational environment to find basic mechanisms of how altered gravitational forces (AGF) affect this reflex. Animals were exposed to microgravity during space flight or hypergravity (3g) for 4 to 12 days. Basic observations were that (1)the development of the rVOR is significantly affected by altered gravitational conditions, (2) the duration of 1g-readaptation depends on the strength of the test stimulus, (3) microgravity induces malformations of the body which are related to the rVOR depression. Future studies are based on the hypotheses (1) that the vestibular nuclei play a key roll in the adaptation to AGF conditions, (2) that the stimulus transducing systems in the sense organ are affected by AGF conditions, and (3) that fertilized eggs will be converted to normal adults guided by physiological and morphological set points representing the genetic programs. Developmental retardation or acceleration, or otherwise occurring deviations from standard development during embryonic and postembryonic life will activate genes that direct the developmental processes towards normality.

Altered gravitational forces affect the development of the static vestibuloocular reflex in fish (Oreochromis mossambicus)

Young fish (Oreochromis mossambicus) were exposed to microgravity (micro g) for 9 to 10 days during space missions STS-55 and STS-84, or to hypergravity (hg) for 9 days. Young animals (stages 11-12), which had not yet developed the roll-induced static vestibuloocular reflex (rVOR) at micro g- and hg-onset, and older ones (stages 14-16), which had already developed the rVOR, were used. For several weeks afterwards, the rVOR was recorded after termination of mug and hg. Here are the main results: (1) In the stage 11-12 fish, the rVOR gain (response angle/roll angle) measured for roll angles 15 degrees, 30 degrees, and 45 degrees was not affected by microgravity if animals were rolled from the horizontal to the inclined posture, but was increased significantly if animals were rolled in the opposite manner. The rVOR amplitude (maximal eye movement during a complete 360 degrees roll) of micro g animals increased significantly by 25% compared to 1g controls during the first postflight week, but decreased to the control level during the second postflight week. Microgravity had no effect in stage 14-16 fish on either rVOR gain or amplitude. (2) After 3g exposure, both rVOR gain and amplitude were significantly reduced for both stage 11-12 and stage 15 fish. One g readaptation was completed during the second post-3g week. Hypergravity at 2 or 2.5 g had no effect. (3) Hypergravity at all three levels tested (2g, 2.5g, and 3g) accelerated the morphological development as assessed by external morphological markers. Exposure to micro g- or 3g-periods during an early developmental period modifies the physiological properties of the neuronal network underlying the static rVOR; in susceptible developmental stages, these modifications include sensitization by microgravity and desensitization by hypergravity.

Syntheses and structural analysis of 10-monoxy- and -dioxy-5-N-substituted iminothianthrene derivatives and the stereochemical change on their sulfur atom under acidic and thermal conditions

5-(N-p)-Toluenesulfonyl)iminothianthrenes, whose sulfur atoms are oxidized to a sulfoxide or sulfone at the 10-position, were hydrolysed readily in high yield to N-unsubstituted-sulfilimines by using concentrated H2SO4. During hydrolysis, 10-monoxy-5-N-unsubstituted-sulfilimines were obtained as a separable mixture of the cis and trans isomers. The stereochemical interconversion of these compounds was studied under both hydrolytic and thermal conditions and their structures were elucidated by using X-ray crystallography.

Bis[N-phenyl(dicyclohexylthiophosphinoyl)thiomethanamido-S, S']copper(II)

The ligands in [Cu(C(19)H(27)NPS(2))(2)] adopt an S,S'-chelation mode leading to an S(4) donor set which defines a square-planar geometry about the Cu atom, which lies on an inversion centre.

(Benzoxazole-2-thiolato-S)(benzoxazole-2-thione-S)bis(triphenylphosph ine)copper(I)

The Cu atom in [Cu(C(7)H(4)NOS)(C(7)H(5)NOS)(C(18)H(15)P)(2)] is tetrahedrally coordinated by a P(2)S(2) donor set. One S atom is derived from neutral benzoxazole-2-thione and the other from the deprotonated form of the ligand. The two sulfur ligands are connected via an N-H.N interaction, leading to the formation of an eight-membered ring.

Effect of first treatment with aminobisphosphonates pamidronate and ibandronate on circulating lymphocyte subpopulations

Up to 60% of patients receiving their first infusion of the bisphosphonate pamidronate experience an acute-phase reaction. In this study, we used flow cytometry to determine the effects of pamidronate treatment on circulating lymphocyte subpopulations, and we investigated whether pamidronate and ibandronate treatment affect lymphocyte subpopulations differently. Twenty patients received a pamidronate infusion, 20 patients received intravenously injected ibandronate, and 10 controls received a clodronate infusion. Pamidronate treatment was followed by a significant increase in median body temperature at the 10-hour measurement and a significant decrease in counts of circulating lymphocytes, natural killer cells, T cells, and CD4+ and CD8+ T-cell subsets. Ibandronate treatment did not affect median body temperature, and it was associated at the 10-hour measurement with maximum increases in total lymphocyte count, B cells, T cells, and CD4+ and CD8+ T-cell subsets. Thus, there is a substantial difference in the hematologic response to initial treatments with pamidronate and ibandronate. Clodronate treatment did not induce changes in body temperature or significantly affect the number of circulating T cells and NK cells. The reduction in lymphocyte subsets after initial pamidronate therapy might be mediated by the release of tumor necrosis factor alpha, whose source in the acute-phase reaction could be T cells.

Self-Assembly of a Radially Functionalized Hexagonal Molecule: Hexakis(4-hydroxyphenyl)benzene

Two different porous hydrogen-bonded networks are formed by self-assembly of the radially substituted host 1. In the network of type A, formed by 1 small middle dot4 Et(2)O, all OH groups of 1 are involved in hydrogen bonding, and the molecular sheets are stacked without translation to generate extended channels that accommodate the Et(2)O molecules. Four OH groups of 1 are involved in the type B network of 1 small middle dot4 DMF, and lateral translation of the sheets in an ABAB sequence generates large chambers, each of which contains four DMF molecules.

Selective changes in EGF receptor expression and function during the proliferation, differentiation and apoptosis of mammary epithelial cells

Epidermal growth factor (EGF) is a multifunctional regulator of mammary epithelial cells (MEC) that transduces its signals through the EGF receptor (EGFR). To clarify the role of the EGFR in the mammary gland, EGFR expression, localization and function were examined during different developmental stages in rats. Immunoblot analysis demonstrated high levels of EGFR during puberty, pregnancy and involution as well as at sexual maturity, and low levels throughout lactation. An immunohistochemical assay was used to show that EGFR was distinctly expressed in a variety of cell types throughout mammary glands from virgin rats and rats during pregnancy and involution, and was down-regulated in all cell types throughout lactation. To examine the relationship between EGFR expression and function, primary MEC were cultured under conditions that induced physiologically relevant growth, morphogenesis and lactogenesis. Cultured MEC expressed an in vivo-like profile of EGFR. EGFR was high in immature MEC, down-regulated in functionally differentiated MEC, and then up-regulated in terminally differentiated and apoptotic MEC. An inhibitor of the tyrosine kinase domain of EGFR was used to demonstrate that EGFR signaling was required for growth and differentiation of immature MEC, and for survival of terminally differentiated MEC, but not for maintaining functional differentiation.

Novel serum markers of bone resorption: clinical assessment and comparison with established urinary indices

Although urinary measurements of collagen degradation provide valid estimates of bone resorption, their clinical application is hampered by pronounced analytical and biological variability. Therefore, immunoassays for the determination of such parameters in serum have been developed. In this study, we assessed the performance of three new serum markers of bone turnover, i.e., C-terminal and N-terminal telopeptides of type I collagen (S-CTX and S-NTX) and bone sialoprotein. Results were compared with urinary total pyridinoline, total deoxypyridinoline, and urinary C-terminal telopeptides of type I collagen (U-CTX) and urinary N-terminal telopeptides of type I collagen (U-NTX). The study population included healthy men (n = 27), premenopausal (n = 30) and postmenopausal (n = 31) women, patients with hepatic dysfunction (HF, n = 24), renal failure (RF, n = 30), breast cancer without (BC-, n = 24) and with (BC+, n = 30) bone metastases, primary vertebral osteoporosis (OPO, n = 27), primary hyperparathyroidism (PHPT, n = 16), active Paget's disease of bone (n = 18), multiple myeloma (MM, n = 18), and patients with hypercalcemia of malignancy before and after treatment with pamidronate (HOM, n = 28). Changes in urinary and serum markers were similar in most metabolic bone diseases. However, differentiation between healthy controls and OPO, or PHPT, was improved by the serum markers. In MM, all serum and urinary markers were elevated (p < 0. 05 vs. controls). In BC+, skeletal involvement was reflected by significant increments in all indices (p < 0.01 vs. BC-), except U-CTX and S-CTX. In HOM, pamidronate-induced changes in biomarkers were most pronounced for U-CTX and S-CTX and S-NTX. HF and RF were associated with elevated levels of all serum markers (p < 0.05 vs. controls). In conclusion, measurements in serum reflect bone resorption to the same extent as the urinary indices. Since serum markers circumvent some of the limitations of urinary measurements, their use potentially improves the assessment of skeletal disorders.

Bartonella koehlerae sp. nov., isolated from cats

Two of the 25 Bartonella isolates recovered during a prevalence study of Bartonella henselae bacteremia in domestic cats from the greater San Francisco Bay region were found to differ phenotypically and genotypically from all prior B. henselae isolates. These isolates, C-29 and C-30, which were recovered from the blood of two pet cats belonging to the same household, grew on chocolate agar as pinpoint colonies following 14 days of incubation at 35 degrees C in a candle jar but failed to grow on heart infusion agar supplemented with 5% rabbit blood. Additional phenotypic characteristics distinguished the isolates C-29 and C-30 from other feline B. henselae isolates. The restriction patterns obtained for C-29 and C-30 by citrate synthase PCR-restriction fragment length polymorphism (RFLP) analysis as well as by genomic RFLP could not be distinguished from each other but were distinctly different from that of the B. henselae type strain. In reciprocal reactions, DNAs from strains C-29 and C-30 were 97 to 100% related under optimal and stringent DNA reassociation conditions, with 0 to 0.5% divergence within related sequences. Labeled DNA from the type strain of B. henselae was 61 to 65% related to unlabeled DNAs from strains C-29 and C-30 in 55 degrees C reactions, with 5.0 to 5.5% divergence within the related sequences, and 31 to 41% related in stringent, 70 degrees C reactions. In reciprocal reactions, labeled DNAs from strains C-29 and C-30 were 68 to 92% related to those of the B. henselae type strain and other B. henselae strains, with 5 to 7% divergence. The 16S rRNA gene sequence of strain C-29 was 99.54% homologous to that of the type strain of B. henselae. On the basis of these findings, the two isolates C-29 and C-30 are designated a new species of Bartonella, for which we propose the name Bartonella koehlerae. The type strain of Bartonella koehlerae is strain C-29 (ATCC 700693).

Light-dependent suppression of the vestibulo-ocular reflex during development

In the fish Oreochromis mossambicus, light conditions affect the development of the roll-induced vestibuloocular reflex (rVOR). During development under continous light-dark conditions the rVOR amplitude, which is the maximum eye movement during a complete 360 degrees lateral roll, shows a secondary drop after a first peak at stage 17 by 64% (36.3 degrees at stage 17; 13.0 degrees at stage 20). This drop was shifted by 2 stages to older postembryonal stages and was 33% (29.2 degrees at stage 20; 19.5 degrees at stage 22) less pronounced in animals which were exposed to complete darkness for several days. Because the period of rVOR diminution is sensitive to light conditions, it is likely that outgrowing visual projection fibres reorganize the neuronal network underlying visual-vestibular behavior thus transiently suppressing the rVOR.

The minimum duration of microgravity experience during space flight which affects the development of the roll induced vestibulo-ocular reflex in an amphibian (Xenopus laevis)

In tadpoles of Xenopus laevis, the effects of microgravity on the development of the roll-induced vestibuloocular reflex (rVOR) was investigated. Special attention was focused on sensitive periods and the minimum duration of microgravity exposure by which the development of the rVOR is affected. The peak-to-peak excursion (rVOR amplitude) of the rVOR characteristic for a lateral 360 degrees roll was used to describe microgravity effects. Fertilization of all eggs was performed 40 h before launch. Tadpoles were exposed to microgravity either during the first (MC-group) or second half of the mission (CM-group), or throughout the 9-day mission (MM-group). Inflight, 1G-gravity was simulated by a centrifuge (CC-group). After termination of the mission, the rVOR amplitude was only reduced in the MM-group with respect to the 1 G-inflight and 1 G-ground control by approximately 20-30% while both the MC- and CM-groups were not affected by the 4-day and 5-day microG exposure, respectively. However, CM-tadpoles like MM-tadpoles showed malformation of their body characterized by a dorsal bended tail. It disappeared in both groups within 2 weeks after landing. The difference between the rVOR amplitudes of the experimental groups disappeared within 5 weeks after landing. The results demonstrate that microgravity retards the development of the rVOR if it lasted longer than 4 days but that tadpoles are susceptible even for shorter periods as shown by the malformation of the body.

Serum-free media for the in vitro cultivation of Cowdria ruminantium

The in vitro culture of Cowdria ruminantium, the causative agent of heartwater in domestic ruminants, was first achieved in 1985; since then, most groups working with this culture system have used media which were supplemented with serum and, in addition, most of them contained tryptose phosphate broth. These undefined products vary from batch to batch and often fail to support the growth of C. ruminantium. We are therefore working towards the development of a completely chemically defined medium for Cowdria culture. We attempted the propagation of the Welgevonden stock of C. ruminantium in bovine endothelial cell cultures in a variety of serum-free culture media. Four synthetic media gave unsatisfactory results, these were: SFRE-199, Iscove's modified Dulbecco's medium, Dulbecco's modified Eagle's medium, and Leibovitz L-15. These media were all supplemented with a proprietary solution A (components solution A of the HL-1 medium kit, containing transferrin, testosterone, sodium selenite, ethanolamine, saturated and unsaturated fatty acids, and stabilizing proteins). Three other serum-free media did support the growth of C. ruminantium: a modified HL-1 medium, Dulbecco's modified Eagle's medium nutrient mixture Ham F-12 (DME/F-12), and RPMI 1640. The chemical composition of DME/F-12 and RPMI 1640 are published, but not that of the HL-1 medium. Each of these media was supplemented with proprietary solution A. Various supplements were investigated as alternative to the incompletely specified solution A; bovine lipoproteins and bovine transferrin were identified as essential supplements which effectively replaced compound solution A. C. ruminantium was propagated in the three growth-supportive media for at least 10 passages.

[Pathogenesis of hypotrophic and eutrophic preterm deliveries --a morphologic study of 212 cases]

The exact pathogenesis of prematurity and intrauterine growth retardation (IUGR) is still obscure in detail. Histological examination of placental tissue may be helpful. In a retro- and prospective study we examined 212 placentas including eutroph-term (n = 80 as controls), hypotroph-term (n = 68), eutroph-preterm (n = 53) and hypotroph-preterm (n = 11) deliveries, respectively. Placentas of the control group showed a significant higher weight, a higher utero-placental diameter and a smaller thickness. We observed villous dysmaturity in a significant higher frequency in risk groups, compared with controls (70-80% vs. 15%). Retarded villous maturity occurred in 38.2% in the hypotroph-term group and in 36.4% in the hypotroph-preterm group, respectively. Placentas of eutroph-preterm deliveries showed a prematurity of the villous tree in 47.2% Our own results and data from literature suggest, that the majority of prematurity and IUGR is not caused by placental dysmaturity itself. Fetal hypotrophy is sometimes caused by inadequate adaptation of the placental tissue due to a virtual slowly appeared disturbance, probably in the uterine maternal blood flow. After the adaptation of placental tissue the organ is able to secure the fetal nutrition supply. A second "hit", e.g. inflammation of the chorion may lead to prematurity. If the compensation of the dysbalance between fetal nutrition-supply and placental capacity is impossible the birth of a premature fetus, mostly dysmature, takes place.

Bone resorption in multiple myeloma and in monoclonal gammopathy of undetermined significance: quantification by urinary pyridinium cross-links of collagen

To quantify osseous breakdown in multiple myeloma (MM), monoclonal gammopathy of undetermined significance (MGUS), and benign osteoporosis, we measured urinary levels of pyridinium cross-links of collagen in 50 patients with newly diagnosed and untreated MM, 40 patients with MGUS, 40 untreated patients with osteoporotic vertebral fractures, and 64 healthy adults. Ion-paired, reverse-phase high-performance liquid chromatography (HPLC) was used to measure total urinary excretion of pyridinoline (h-PYD) and deoxypyridinoline (h-DPD). Urinary excretion of free immunoreactive deoxypyridinoline (i-DPD) was determined with an enzyme immunoassay. MM patients had significantly (P < .0001) higher levels of h-PYD, h-DPD, and i-DPD than the healthy adults, patients with MGUS, or patients with osteoporosis. The MGUS and osteoporosis groups presented with elevated (P < .05) levels of urinary pyridinium cross-links when compared with healthy controls. In 20 MM patients who subsequently received chemotherapy, the percent changes in i-DPD did not correlate with the changes in the monoclonal protein. In one of three patients experiencing a transition of initial MGUS into stage I MM, i-DPD increased above the upper limit of the normal range. In 13 patients with stable MGUS, i-DPD remained normal in repeated measurements. Based on the upper limits of the normal range, the sensitivity of urinary pyridinium cross-links in stage I and II MM was low (<50%), but it was between 78% (h-DPD) and 93% (i-DPD) in stage III MM. Specificity in patients with MGUS was between 87% (h-PYD) and 97% (h-DPD). In conclusion, determining the urinary excretion of pyridinium cross-links seems to be a promising noninvasive and thus easily repeatable method for evaluating the actual degree of osseous breakdown. Although measurement of pyridinium cross-link levels is not useful in discriminating patients with MGUS from early-stage myeloma patients, determination of i-DPD levels may contribute importantly to clinical guidance, since increased i-DPD levels seem to identify patients who are particularly likely to benefit from osteoclast-inhibiting drugs such as bisphosphonates. The fact that in a number of patients paraprotein concentrations and i-DPD levels did not change in parallel but instead diverged strongly after chemotherapy might explain the observation that bone lesions sometimes progress even in patients who achieve complete remission.

In vitro isolation and cultivation of Cowdria ruminantium under serum-free culture conditions

Three stocks of Cowdria ruminantium, the causative agent of heartwater in domestic ruminants, were propagated in bovine endothelial cells in a serum-free culture medium. The Vosloo, Welgevonden and Senegal stocks were propagated for a period of more than 203, 134, and 43 days, respectively. Two of the C ruminantium stocks (Vosloo and Senegal) were also successfully initiated under serum-free culture conditions. The serum-free medium consisted of a modified HL-1 medium. The Senegal stock was successfully propagated in Dulbecco's modified Eagle's medium nutrient mixture Ham F-12 containing 10 per cent fetal bovine serum.

Some haematological and immunological parameters of farmed deer in Hungary

A haematological survey of farmed fallow deer (Dama dama) and red deer (Cervus elaphus) was carried out. In the winter period the red blood cell (RBC) count was 9.0 x 10(12)/L in adult fallow-does, and 6.1 x 10(12)/L in fawns. The haemoglobin (Hb) level and mean corpuscular volume (MCV) were also significantly (P < 0.05) lower in fawns than in adult fallow deer. In blood samples taken from red deer in different physiological and nutritional periods, the stags showed the lowest mean RBC count in January (4.7 x 10(12/L) and the hinds during lactation (6.3 x 10(12)/L). The mean RBC count of samples taken from a group of red deer fawns at five different times between 1 week and 1 year of age varied between 5.8 and 7.0 x 10(12)/L. In red deer herds the RBC count showed minor variations and the Hb concentration was almost constant in the different periods. The coefficient of correlation between RBC and Hb was 0.66 and 0.58 in fallow deer and red deer, respectively. Studying the blastogenic transformation of lymphocytes by immunological tests, a higher rate of response to non-specific mitogens (Phaseolus vulgaris, PHA; concanavalin A, Con A) was found in farmed deer (> 30%) than in deer captured in the wild and kept under farm conditions for 10 or 13 months (< 20%).

Altered gravitational experience during early periods of life affects the static vestibulo-ocular reflex of tadpoles of the southern clawed toad, Xenopus laevis Daudin

The effects of altered gravitational forces (AGF) on the development of the static vestibulo-ocular reflex (VOR) were investigated in Xenopus laevis tadpoles exposed to hypergravity (1.4g; 3g) or microgravity conditions (German spacelab mission D-2) for 9-10 days. The effects of light conditions during development were also tested by exposing tadpoles to either complete darkness (DD) or 12:12 h light-dark conditions (LD). The static VOR was induced by lateral roll. The efficacy of the VOR circuit after termination of AGF conditions was described by the peak-to-peak amplitude of the sinusoidal VOR characteristics (i.e. amplitude). The static VOR was first observed at stage 41 for both LD and DD tadpoles. Its further development was retarded in the DD tadpoles compared with the LD tadpoles up to stage 48. Microgravity as well as hypergravity exposure caused a significant (P < 0.05, at least) decrease in the static VOR amplitude during the first week after termination of the AGF period. The decreases were 39.4% in the microgravity group, 16.2% in the 1.4g group and 24.9-42.9% in the 3g group compared with the 1g ground-reared siblings at the same developmental stages. The response deficits usually disappeared but persisted for at least 2 weeks in animals whose development was retarded by hypergravity exposure. It is postulated (i) that gravity exerts an important influence on the normal development of the roll-induced static VOR; (ii) that hypergravity exposure decreases the sensitivity of the gravity-sensitive system so that recordings under 1g conditions cause a weaker static VOR; and (iii) that the vestibulo-spinal pathway possesses a higher degree of plasticity than the vestibulo-ocular pathway.

A hypergravity related sensitive period during the development of the roll induced vestibuloocular reflex in an amphibian (Xenopus laevis)

In tadpoles of Xenopus laevis, the effects of an exposure to hypergravity on the development of the roll-induced static vestibuloocular reflex (rVOR) were investigated. Special attention was given to the onset of the 9 or 12 days lasting 3 g period during early life. Recordings of rVOR characteristics for complete 360 degrees rolls of the tadpoles started 24 h after the end of the 3 g period. The rVOR peak-to-peak amplitudes from the 3 g samples recorded at the 2nd and 3rd day after termination of the 3 g exposure agreed with that recorded from the 1 g reared tadpoles for the youngest group, but were reduced by 30% in the older tadpoles. During further development under 1 g condition, the rVOR amplitude of tadpoles with 3 g experience did not change if the 3 g exposure started before the first appearance of the rVOR, but increased if it had started thereafter, albeit on a lower level than that of the 1 g reared siblings. The results support the existence of a sensitive period for the rVOR development, and additionally demonstrate that the period during which the rVOR appeared for the first time is an important milestone for the development of adaptive properties of the underlying neuronal network.

Serum immunoreactive bone sialoprotein as a new marker of bone turnover in metabolic and malignant bone disease

Bone sialoprotein (BSP) is a phosphorylated glycoprotein with a M(r) of 70-80 kDa that accounts for approximately 5-10% of the noncollagenous proteins of bone. Due to its relatively restricted distribution to mineralized tissues, BSP may serve as a potential marker of bone metabolism. Employing a recently developed RIA, serum BSP was measured in 133 healthy subjects, aged 20-80 yr, and in patients with primary hyperparathyroidism (pHPT; n = 26), Paget's disease of bone (PD; n = 14), untreated multiple myeloma (MM; n = 32), and breast cancer with bone metastases (BC; n = 19). Results were compared to clinical and laboratory data, including serum total alkaline phosphatase as a marker of bone formation, and the urinary cross-links pyridinoline (PYD) and deoxypyridinoline (DPD) as markers of bone resorption. In healthy adults, serum BSP values ranged between 5.0-21.6 ng/mL (5-95% interval), with a median of 10.5 ng/mL (total group). In healthy females, a linear correlation was found between serum BSP and age (r = 0.51; P < 0.001), with significantly higher values in postmenopausal than in premenopausal women (13.3 +/- 4.8 vs. 9.0 +/- 3.8; P < 0.01). In the healthy group, BSP values did not change with body mass index, lumbar bone mineral density, serum calcium, serum creatinine, or serum total alkaline phosphatase levels. In contrast, a weak, but significant, correlation was observed between serum BSP and the urinary excretion of PYD and DPD. Compared to those in healthy controls, serum BSP levels were significantly higher in patients with pHPT, PD, MM, or BC (P < 0.01 for all groups). These differences remained after analyses were adjusted for age and sex. In pHPT, serum BSP levels were closely correlated to urinary PYD and DPD (r = 0.87 and 0.83, respectively; P < 0.01), whereas in PD, no correlation was observed between any of the bone markers. Serum BSP levels were highest in patients with MM, and there was a significant difference between early and advanced stages of the disease (30.2 +/- 8.0 vs. 64.3 +/- 6.8; P < 0.01). In a subgroup of 15 patients with metastatic BC, iv bisphosphonate treatment resulted in a rapid reduction of serum BSP levels to 40% of the baseline values within 4 days of treatment. In conclusion, BSP appears to be a sensitive marker of bone turnover, and the present data suggest that its serum levels predominantly reflect processes related to bone resorption.

Expression of epileptiform activity induced by a penicillin focus within the posterior thalamus in the awake rat

Investigations were performed to study the epileptiform activity, induced by a local injection of penicillin (PCN) into the posterior thalamus (pTh) of the awake rat, and to compare it with the epilepsy induced in the same animals 2 weeks later by an injection of PCN into the motor cortex (MC). Using EEG recordings, 1) the distribution of focal cortical activity, and 2) the severity of the epileptiform activity (frequency of focal activity, occurrence and duration of generalized episodes) were analyzed. The focal activity of pTh rats was characterized by two types of potentials: (a) sharp potentials with a spike-like shape that developed during the first hour after PCN injection only in the visual cortex, but in the transition area between the motor and sensory cortex during the last period of epileptiform activity; and (2) large potentials with a wave- or spike-wave-like shape that had their center of focal expression in the transition zone between the motor and sensory cortex. MC rats exhibited only a spike-like potential with or without short-lasting afterdischarges in the homotopic areas of the MC of both hemispheres. During periods with large potentials only, the number of generalized episodes was significantly reduced with respect to those periods with sharp potentials. When the epileptiform activity changed from large to sharp potentials, the interictal frequency increased significantly. It is postulated (a) and a pTh focus activates the lateral and/or the reticular thalamic areas, which, due to their high intrinsic potential for synchronization, cause a self-sustained interictal activity of the large potential type; and (b) that the wave of the large potentials is involved in an anticonvulsive mechanism that reduces the extent of ictal as well as interictal activity.

Comparison of some blood parameters of captured and farmed red deer (Cervus elaphus) hinds

In studies on the adaptation of red deer (Cervus elaphus) to farm conditions, some blood parameters of 3- to 9-year-old captured and farmed hinds were compared. The test variable included blood plasma creatine kinase (CK), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) activities, the concentrations of glucose, urea, total protein (TP), serum cortisol, haemoglobin (Hb), and the blastogenic transformation of lymphocytes upon stimulation by the nonspecific mitogens Phaseolus vulgaris (PHA) and Concanavalin A (ConA) in the lymphocyte stimulation test (LST). The effects exerted by probiotic preparation (Ascogen) on the same parameters were studied in farmed deer. In hinds that had been kept under farm conditions for 10 months, CK activity was lower (P < 0.05) and blood urea concentration higher (P < 0.001) than at the time of capture, while their blood glucose concentration exceeded (P < 0.01) that of farmed hinds. Hinds treated with Ascogen had lower ALT activity (P < 0.001) and showed a higher increase in PHA-induced blastogenic transformation of lymphocytes than the control hinds.

KATP channel opening does not contribute significantly to the vasodilatory effect of SH-group-containing ACE inhibitors

Angiotensin-converting enzyme (ACE) inhibitors are widely used in the management of hypertension, heart failure, and nephropathy. It has been suggested that ACE inhibitors containing the sulfhydryl group (SH) have an additional effect on KATP channels. To prove this hypothesis, we studied the effects of the SH-containing ACE inhibitors, captopril and zofenopril, on KATP channel opening of bovine coronary arteries and guinea pig thoracic aortas. Bovine coronary arteries were precontracted with the thromboxane A2 analogue, U46619, and guinea pig thoracic aortas were precontracted with phenylephrine and then relaxed with either captopril or zofenopril (n = 8). Inhibition of KATP channel opening with glibenclamide moderately attenuated the zofenopril-induced relaxation of guinea pig thoracic aorta. However, in the bovine coronary arteries, the relaxing effect of both captopril and zofenopril remained uneffected by glibenclamide. In experiments with enalapril (a non SH-containing ACE inhibitor; n = 6) on guinea pig thoracic aortas, no effect on KATP channels could be seen. From our experiments, we conclude that the postulated opening of KATP channels by SH-group-containing ACE inhibitors contributes little to the vasodilation of guinea pig thoracic aortas caused by ACE inhibitors, and that SH groups have no influence upon KATP channels of bovine coronary arteries.

Early development in aquatic vertebrates in near weightlessness during the D-2 Mission STATEX project

Aboard the German-Spacelab-Mission D-2 the project "Gravity Perception and Neuronal Plasticity (STATEX II)" was performed. STATEX is for STATolith EXperiment. Objects were growing tadpoles of the South African Toad (Xenopus laevis D.) and a juvenile cichlid fish (Oreochromis mossambicus). The results give a broader base for the understanding of how environmental stimuli (e.g. linear accelerations) affect the development and function of the gravity perceiving systems in these two vertebrates. These systems are accepted as models for the human vestibulum. Results of experiments in hyper-g (up to 5 g), simulated weightlessness (Fast-rotating-clinostat) and parabolic flights are compared and discussed.

Readaptation of the vestibuloocular reflex to 1g-condition in immature lower vertebrates (Xenopus laevis) after micro- or hypergravity exposure

The effects of altered gravitational conditions (AGC) on the development of the static vestibulo-ocular reflex (VOR) and readaptation to 1g were investigated in the amphibian Xenopus laevis. Tadpoles were exposed to microgravity during the German Space Mission D-2 for 10 days, using the STATEX closed survival system, or to 3g for 9 days during earth-bound experiments. At the beginning of AGC, the tadpoles had not yet developed the static VOR. The main results were: (i) Tadpoles with microgravity- or 3g-experience had a lower gain of the static VOR than the 1g-controls during the 2nd and 5th post-AGC days. (ii) Readaptation to response levels of 1g-reared controls usually occurred during the following weeks, except in slowly developing tadpoles with 3g-experience. Readaptation was less pronounced if, during the acute VOR test, tadpoles were rolled from the inclined to the normal posture than in the opposite test situation. It is postulated that (i) gravity is necessarily involved in the development of the static VOR, but only during a period including the time before onset of the first behavioural response; and (ii) readaptation which is superimposed by the processes of VOR development depends on many factors including the velocity of development, the actual excitation level of the vestibular systems and the neuroplastic properties of its specific pathways.

Double-blind, placebo-controlled study of the long-term efficacy of carvedilol in patients with severe chronic heart failure

BACKGROUND

Clinical trials have shown that beta-adrenergic blocking drugs are effective and well tolerated in patients with mild to moderate heart failure, but the utility and safety of these drugs in patients with advanced disease have not been evaluated.

METHODS AND RESULTS

We enrolled 56 patients with severe chronic heart failure into a double-blind, placebo-controlled study of the vasodilating beta-blocker carvedilol. All patients had advanced heart failure, as evidenced by a mean left ventricular ejection fraction of 0.16 +/- 0.01 and a mean maximal oxygen consumption of 13.6 +/- 0.6 mL.kg-1.min-1 despite digitalis, diuretics, and an angiotensin-converting enzyme inhibitor (if tolerated). After a 3-week, open-label, up-titration period, 49 of the 56 patients were assigned (in a double-blind fashion using a 2:1 randomization) to receive either carvedilol (25 mg BID, n = 33) or matching placebo (n = 16) for 14 weeks, while background therapy remained constant. Hemodynamic and functional variables were measured at the start and end of the study. Compared with the placebo group, patients in the carvedilol group showed improved cardiac performance, as reflected by an increase in left ventricular ejection fraction (P = .005) and stroke volume index (P = .010) and a decrease in pulmonary wedge pressure, mean right atrial pressure, and systemic vascular resistance (P = .003, .002, and .017, respectively). In addition, compared with placebo, patients treated with carvedilol benefited clinically, as shown by an improvement in symptom scores (P = .002), functional class (P = .013), and submaximal exercise tolerance (P = .006). The combined risk of death, worsening heart failure, and life-threatening ventricular tachyarrhythmia was lower in the carvedilol group than in the placebo group (P = .028), but carvedilol-treated patients had more dizziness and advanced heart block.

CONCLUSIONS

Carvedilol produces clinical and hemodynamic improvement in patients who have severe heart failure despite treatment with angiotensin-converting enzyme inhibitors.

Microinjections of GABAergic agents in the locus coeruleus modify the gain of vestibulospinal reflexes in decerebrate cats

1. Precollicular decerebrate cats show a good postural activity in the four limbs and a small-amplitude vestibulospinal (VS) reflex, as revealed by recording the EMG response of the triceps brachii to sinusoidal roll tilt of the animal at 0.15 Hz, +/- 10 degrees. This preparation was used to study whether inactivation of the locus coeruleus (LC) elicited by local administration either of the GABA-A agonist muscimol or of the GABA-B baclofen produced changes in posture as well as in gain of the VS reflexes. 2. Microinjection into the LC of one side of 0.13-0.25 microliter of a muscimol or baclofen solution (at 2.5 or 1 microgram/microliter saline, respectively) stained with 5% pontamine, usually decreased the extensor tonus in the ipsilateral limbs and to a lesser extent also in the contralateral limbs. However, the amplitude of modulation and thus the gain of the first harmonic component of the multiunit EMG responses of the ipsilateral and to a lesser extent also of the contralateral triceps brachii to the same parameters of labyrinth stimulation increased. The phase angle of the responses remained nearly unchanged by this treatment. The effects appeared 5-10 min after the injection of muscimol, fully developed in 30 min and progressively declined within the following 2-2.5 hours. 3. The increased gain of the VS reflexes acting on the triceps brachii did not depend on the decreased postural activity following the injection of the GABA-A or GABA-B agonist, since it was still observed if the reduced EMG activity following the injection was compensated by an increased static stretch of the muscle. Moreover, the postural and reflex changes described above were not due to irritative events following the injection, since they were not observed in control experiments following injection of 0.25 microliter saline within the LC-complex. On the other hand, postural and reflex changes opposite in sign to those elicited by muscimol or baclofen were obtained by local injection into the LC-complex of a GABA-A or GABA-B antagonist (0.25 microliter of bicuculline or faclofen at 8 micrograms/microliters saline). 4. In some experiments, the decrease in postural activity of the forelimbs after injection of muscimol into the LC complex was followed by transient episodes of postural atonia, which affected not only the ipsilateral but also the contralateral triceps muscles.(ABSTRACT TRUNCATED AT 400 WORDS)

Ritanserin, imipramine, and placebo in the treatment of dysthymic disorder

Fifty outpatients with dysthymic disorder (DSM-III) were divided by double-blind randomized assignment into three groups given ritanserin, imipramine, and placebo, respectively. The trial was of 7 weeks' duration; by week 6, imipramine was clearly superior to placebo, whereas by week 7, both drugs caused significantly more improvement than the placebo. Although imipramine had slightly greater efficacy than ritanserin, it also had significantly more side effects. This was particularly evident in the higher dropout rate with imipramine. The efficacy and side effect profile of ritanserin makes it well tolerated and acceptable with dysthymic patients who, although they do not respond as quickly as patients with major depressive disorder, do show significant improvement, given sufficient time.

Modulation of vestibulospinal reflexes through microinjection of an alpha 1-adrenergic antagonist in the dorsal pontine tegmentum of decerebrate cats

1. The possibility that the norepinephrine (NE)-containing locus coeruleus (LC) neurons produce changes in posture as well as in gain of the vestibulospinal (VS) reflexes by acting on the dorsolateral pontine tegmentum (DPT) and the related medullary inhibitory reticulospinal (RS) system through alpha 1-adrenoceptors has been investigated in decerebrate cats. 2. Injection of the alpha 1-adrenergic antagonist prazosin PRZ (0.25 microliter at 0.1-1 microgram/microliter solvent) into the DPT, namely in the dorsal pontine reticular formation (pRF), as well as in the peribrachial nucleus of one side, decreased the postural activity in the ipsilateral limbs while increasing that of the contralateral limbs. In addition, the amplitude of modulation and thus the gain of the multiunit EMG responses of the ipsilateral and to a lesser extent of the contralateral triceps brachii to roll tilt of the animal at 0.15 Hz, +/- 10 degrees, increased. These effects appeared 5-10 min after the injection, reached the highest values in about 40-60 min and persisted for additional 1.5-2 h before disappearing. 3. The effects were site-specific and to some extent dose-dependent. However, neither changes in posture nor in gain of the VS reflexes were obtained after injection in the effective area of an equal volume of solvent. 4. In order to account for these findings it was postulated that the alpha 1-antagonist blocks the tonic inhibitory influence that the NE-containing LC neurons exert on ipsilateral DPT either by exciting through alpha 1-receptors interposed inhibitory interneurons, or by inhibiting presynaptically excitatory afferents to the same pontine tegmental structures. The increased discharge of these neurons and the related medullary inhibitory RS neurons would reduce the postural activity in the ipsilateral limbs. However, since the inhibitory RS neurons show a response pattern to tilt opposite in sign to that elicited by the excitatory VS neurons, we could expect that for a given labyrinth signal, the increased discharge of the RS neurons in the animal at rest would lead to a greater disinhibition of limb extensor motoneurons during ipsilateral tilt. These motoneurons would then respond more efficiently to the same excitatory volleys elicited by given parameters of stimulation, thus leading to an increased gain of the EMG responses of forelimb extensors to labyrinth stimulation. The possibility that the DPT of one side activates inhibitory RS neurons of both sides explains why PRZ increases the gain of the VS reflexes not only ipsilaterally but also contralaterally to the side of the injection.(ABSTRACT TRUNCATED AT 400 WORDS)

Arrest of seizure series induced by an intracortical injection of penicillin in the awake rat

Experiments were performed to answer the question, whether series of generalized tonic-clonic seizures, induced in the awake rat by a local injection of Na-penicillin (PCN) solution into the motor cortex, terminates at the same critical concentration Ct of PCN within the focal area independently of the concentration C0 of PCN injected. Using the PCN diffusion coefficient D = 3.52 x 10(-4) mm2/s and the tortuosity factor lambda = 1.62, the concentration Ct at the onset of the last generalized seizure was calculated. The median duration of seizure series increased from 32 to 190 min, when the dose of injected PCN was raised from 32 to 1000 IU. At the onset of the last seizure, the median concentration Ct within the artificial focus ranged from 2.1 to 4.0 IU/0.5 microliter saline in rats treated with 32 to 125 IU PCN. After induction of convulsive behaviour with C0 = 250, 500, or 1000 IU PCN/0.5 microliter saline, however, Ct was at a higher level between 6.1 and 7.4 IU PCN/0.5 microliter saline. The difference between the cumulated data from the low-dose vs. the high-dose range was significant (p < 0.01). It is concluded that during long-lasting series of generalized seizures, the brain takes advantage of its plastic properties. By forming a counteracting mechanism, it protects itself from extreme epileptiform activity. This autoprotection may be due to the activation of neuronal networks which probably needs a certain frequency of seizures to become operatively.

The benefits of clomipramine-fluoxetine combination in obsessive compulsive disorder

We report the benefits of clomipramine-fluoxetine combination in four cases of severe obsessive compulsive disorder. In two cases, the combination was effective when either drug used singly was ineffective. In the other two cases, fluoxetine adjunct produced benefits with no additional side effects.

[Ring-valve abscess--a diagnostic challenge]

Infective endocarditis is a life-threatening disease which may be complicated by ring-valve abscess. Since this complication increases morbidity and mortality early diagnosis is important. Pericardial effusion complicating infective endocarditis is uncommon and should raise suspicion of the presence of an abscess. We describe 2 patients admitted for infective endocarditis and pericarditis. In both, ring-valve abscess was suspected on clinical grounds. At surgery there was pathological confirmation of the diagnosis. Both patients underwent successful aortic valve replacement with complete recovery. Controlled trials are providing increasing evidence for the superiority of transesophageal echocardiography in detecting valvular vegetations. Moreover, it is the most accurate means of detecting ring-valve abscess in cases of infective endocarditis. In view of these advantages, we propose the use of transesophageal echocardiography in every case of infective endocarditis.