Effect of increasing dietary threonine intakes on amino acid metabolism of the central nervous system and peripheral tissues in growing rats

Although clinical rating scales and simple timed tests of motor function are widely used to assess motor response to therapy, gait analysis may provide an alternative measure of this response. We studied 15 patients with PD complicated by motor fluctuations, first to determine changes in temporal and spatial gait parameters following levodopa, secondly to assess the stability of repeated gait measures and timed tests in "off" and "on" states, and thirdly to determine the use of gait analysis in the assessment of the dopaminergic response. Gait analysis (velocity, stride length, cadence, and double limb support), clinical rating scales (modified Webster scale and Hoehn and Yahr stage), and timed tests of motor function (hand tapping and stand-walk-sit time) were performed before ("off") and after ("on") a levodopa challenge. Stride length and gait velocity increased following medication whereas cadence and double limb support did not. Most gait measures and the stand-walk-sit time were stable over three consecutive trials in both "off" and "on" states. Of the gait measures, only cadence in the "off" state changed significantly whereas the tapping count improved with repeated trials in both "off" and "on" states. Changes in stride length, gait velocity, and tapping count following levodopa correlated with changes in clinical rating scales following treatment. Measurement of gait parameters provides a reliable, objective alternative to rating scales and timed tests in assessing the dopaminergic response in patients with PD and motor fluctuations.     

Growth inhibition of K-ras-expressing tumours by a new vinca alkaloid, conophylline, in nude mice

Conophylline, a new vinca alkaloid isolated from the plant Ervatamia microphylla induced normal flat morphology in K-ras-NRK and K-ras-NIH cell lines, and lowered the increased uptake of 2-deoxyglucose in K-ras-NRK cells. Conophylline inhibited the growth of K-ras-NRK cells, but this inhibition was reversible. The alkaloid also inhibited the growth of K-ras-NRK and K-ras-NIH3T3 tumours transplanted into nude mice. On the other hand, it showed no effect on survival of the mice loaded with L1210 leukaemia. Thus, conophylline is a new antitumour vinca alkaloid that induced normal phenotypes in ras-expressing cells.     

Effect of omega-3 fatty acids on the progression of metastases after the surgical excision of human breast cancer cell solid tumors growing in nude mice

We showed previously that a diet rich in linoleic acid (LA), an omega-6 fatty acid, stimulates the growth and metastasis of human breast cancer cells in athymic nude mice. In contrast, diets supplemented with eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA), omega-3 fatty acids, exert suppressive effects. We have now assessed EPA and DHA as adjuvant nutritional therapy in the nude mouse model and compared the responses when the intervention was commenced 1 week before ("neoadjuvant") or immediately after ("postoperative adjuvant") surgical excision of the primary tumor. Female nude mice received a high-fat, 8% LA diet beginning 7 days before 10(6) MDA-MB-435 human breast cancer cells were injected into a thoracic mammary fat pad. As the tumor surface areas approached 0. 7 cm2, the mice were assigned to either continue on the LA-rich diet or to commence one containing 8, 4, or 2% EPA or DHA. Seven days later, the mammary fat pad tumors were excised; the mice still consuming the 8% LA diet were then allocated sequentially to either continue this diet or commence one of the six postexcision omega-3 fatty acid dietary interventions. Eight weeks later, the mice were necropsied and evaluated for local recurrence and lung metastases. Although there were no differences in the incidence of local recurrence between groups, EPA and DHA both inhibited the development of lung metastases. When the dietary interventions were commenced 7 days before surgery, the severity of lung metastasis was reduced by the two omega-3 fatty acids in a dose-dependent manner; at all three levels, the suppressive effects were statistically significant (P < 0.05). Postexcision EPA treatment produced small, statistically insignificant effects, but lung involvement was reduced significantly by feeding DHA at the 2 and 4% levels (P < 0. 05). Overall, these results suggest that omega-3 fatty acids may have a place as adjuvant nutritional therapy in breast cancer and particularly as part of a neoadjuvant regimen.     

Kinetics of subcutaneous versus intravenous epoetin-beta in dogs, rats and mice

The total body clearance of recombinant human erythropoietin (rhEPO) calculated per kilogram of body weight increased in the order man = dog < rat < mouse. The differences disappeared or were reversed when clearance was expressed per square meter of body surface. There was no similar species difference in terminal half life. Total body clearance increased with the dose in dogs and mice, but not in rats. The bioavailability from a subcutaneous depot was 80% in dogs, 76% in rats, and 70% in mice. The absorption from the subcutaneous depot is rapid in rats and mice, but slow in dogs. The pharmacodynamic activity of rhEPO injected by both routes was compared in polycythemic mice. The equipotent doses were 2.44 times higher with intravenous than with subcutaneous injection. Taking into account the bioavailability of 70% from a subcutaneous depot, one obtains a potency ratio of 3.5 for absorbed subcutaneous versus intravenous rhEPO.     

Effect of dopamine on immune cell proliferation in mice

Dopamine is known as a precursor of catecholamine and one of the neurotransmitters in brain and peripheral tissues. Recent studies suggest an important role of dopamine in immune responses. In the present study, intraperitoneal administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) which lowered endogenous dopamine suppressed splenocyte proliferation in response to mitogens such as lipopolysaccharide (LPS) and concanavalin A (Con A). Moreover, intravenous injection of the specific agonists of dopamine DA-1 receptor (SKF38393) or DA-2 receptor (LY171555) into mice enhanced the splenocyte proliferation stimulated by LPS or Con A. In the in vitro cultures, dopamine, SKF38393 and LY171555 directly promoted cell proliferation to LPS or Con A. These results indicate that dopamine has an ability to regulate B- and T-cell proliferation both in vivo and in vitro.     

Fixation of spinal reflexes in rats by central and peripheral sensory input.

Used 2 methods in 5 experiments (55 male hooded Long-Evans rats) to demonstrate retention of postural asymmetries after spinal cord section. In the 1st preparation, postural asymmetries of the hindlimbs were induced by placing electrolytic lesions in the anterior cerebellum. Asymmetry was found to consistently outlast a spinal cord section if 45 min were allowed between brain lesion and cord section. A certain percentage of Ss allowed 35 or 40 min also demonstrated the retention. In the 2nd preparation, postural asymmetries induced by 45 min of direct hindlimb stimulation were also retained after spinal section. Rhizotomy prior to stimulation resulted in a lack of appreciable asymmetry on termination of the stimulation. Retention of a hindlimb-stimulation-induced asymmetry was observed in Ss that underwent a spinal section before stimulation. Results demonstrate that the "spinal fixation" phenomenon can be obtained by induction of postural alterations from central (cerebellar lesion) and peripheral (hindlimb stimulation) sources. Results obtained from spinal Ss indicate that retention of peripherally induced asymmetry is not crucially dependent on higher brain center activity but rather seems to be more dependent on long-term alterations that occur directly in the spinal reflex system. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Kinetics of cell proliferation and polyamine synthesis during Ehrlich ascites tumor growth

The kinetics of cell proliferation and polyamine synthesis during Ehrlich ascites tumor growth were studied. The steady deceleration of the specific growth rate with increasing tumor mass that was observed was attributable to a prolongation of the cell cycle, particularly of the S and G2 phases. The cell cycle time (Tc) was 43.3 hr (TG1 equals 10.8, TS equals 26.8, and TG2 equals 5.7 hr) on the seventh day of growth and 76.0 hr (TG1 equals 14.0, TS equals 52.0, and TG2 equals 10.0 hr) on the tenth day of growth. The growth fraction showed a decrease from 0.77 to 0.60 during the 7- to 10-day tumor growth interval. The cell death rate remained low and essentially unchanged during this period. A high correlation was found between polyamine synthesis (ornithine decarboxylase activity) and the specific growth rate; the correlation coefficient was 0.985. There was also a high positive correlation between the cellular polyamine (spermidine and spermine) and nucleic acid content (spermidine: DNA equals 0.916, spermine: DNA equals 0.947, spermidine:RNA equals 0.907, and spermine: RNA equals 0.881). These observations suggest that there may be a functional coupling between polyamines and nucleic acids, and they support the hypothesis that polyamines play an important role in DNA replication and cell division.     

Intraoral giant cell lesions: the peripheral and central forms of these entities

Giant cell lesions have long been of interest as to their origins and pathogenesis. These lesions range from the unusual and rare heritable case of Cherubism to the more often encountered peripheral giant cell lesion (granuloma). While some giant-cell-containing entities appear as innocuous lesions, others form tumorous masses and are locally destructive in nature. Early diagnosis and treatment are important to overall patient health and prevention of local tissue destruction. The learning objective of this article is to familiarize the clinician with the most common of these entities-the peripheral and the central giant cell lesions.     

Kinetics of photobleaching of protoporphyrin IX in the skin of nude mice exposed to different fluence rates of red light

The present study evaluates the effect of blood volume expansion on the gastrointestinal transit of a charcoal meal (2.5 ml of an aqueous suspension consisting of 5% charcoal and 5% gum arabic) in awake male Wistar rats (200-270 g). On the day before the experiments, the rats were anesthetized with ether, submitted to left jugular vein cannulation and fasted with water ad libitum until 2 h before the gastrointestinal transit measurement. Blood volume expansion by i.v. infusion of 1 ml/min Ringer bicarbonate in volumes of 3, 4 or 5% body weight delayed gastrointestinal transit at 10 min after test meal administration by 21.3-26.7% (P < 0.05), but no effect was observed after 1 or 2% body weight expansion. The effect of blood volume expansion (up to 5% body weight) on gastrointestinal transit lasted for at least 60 min (P < 0.05). Mean arterial pressure increased transiently and central venous pressure increased and hematocrit decreased (P < 0.05). Subdiaphragmatic vagotomy and yohimbine (3 mg/kg) prevented the delay caused by expansion on gastrointestinal transit, while atropine (0.5 mg/kg), L-NAME (2 mg/kg), hexamethonium (10 mg/kg), prazosin (1 mg/kg) or propranolol (2 mg/kg) were ineffective. These data show that blood volume expansion delays the gastrointestinal transit of a charcoal meal and that vagal and yohimbine-sensitive pathways appear to be involved in this phenomenon. The delay in gastrointestinal transit observed here, taken together with the modifications of gastrointestinal permeability to salt and water reported by others, may be part of the mechanisms involved in liquid excess management.     

Orthotopic growth and metastasis of human non-small cell lung carcinoma cell injected into the pleural cavity of nude mice

An automated two column HPLC system with the new packing material LiChrospher RP-18 ADS (alkyl-diol-silica) was tested for the determination of several drugs and metabolites (talinolol, celiprolol, metoprolol, oxprenolol, triamterene, trimethoprim, tiracizine, articaine, detajmium, ajmaline, lamotrigine) in various biological fluids (serum, urine, intestinal aspirates, supernatants of cell cultures and supernatants after protein denaturation). The method allows the direct injection of biological fluids into a reversed-phase HPLC system and on-line clean-up and sample enrichment by a column-switching technique. Precision, accuracy and sensitivity were similar to conventional assays as described in the literature. With this new method it was possible to measure drug concentrations in various biological fluids without changing the sample preparation procedure. In some cases an additional sample preparation like protein denaturation or solid-phase extraction was advantageous to enhance the sensitivity of the method and the life-time of the ADS column.     

Norepinephrine loss selectively enhances chronic nigrostriatal dopamine depletion in mice and rats

A total of 3,700 Pseudomonas aeruginosa isolates were collected from 17 general hospitals in Japan from 1992 to 1994. Of these isolates, 132 carbapenem-resistant strains were subjected to DNA hybridization analysis with the metallo-beta-lactamase gene (blaIMP)-specific probe. Fifteen strains carrying the metallo-beta-lactamase gene were identified in five hospitals in different geographical areas. Three strains of P. aeruginosa demonstrated high-level imipenem resistance (MIC, > or = 128 micrograms/ml), two strains exhibited low-level imipenem resistance (MIC, < or = 4 micrograms/ml), and the rest of the strains were in between. These results revealed that the acquisition of a metallo-beta-lactamase gene alone does not necessarily confer elevated resistance to carbapenems. In several strains, the metallo-beta-lactamase gene was carried by large plasmids, and carbapenem resistance was transferred from P. aeruginosa to Escherichia coli by electroporation in association with the acquisition of the large plasmid. Southern hybridization analysis and genomic DNA fingerprinting profiles revealed different genetic backgrounds for these 15 isolates, although considerable similarity was observed for the strains isolated from the same hospital. These findings suggest that the metallo-beta-lactamase-producing P. aeruginosa strains are not confined to a unique clonal lineage but proliferated multifocally by plasmid-mediated dissemination of the metallo-beta-lactamase gene in strains of different genetic backgrounds. Thus, further proliferation of metallo-beta-lactamase-producing strains with resistance to various beta-lactams may well be inevitable in the future, which emphasizes the need for early recognition of metallo-beta-lactamase-producing strains, rigorous infection control, and restricted clinical use of broad-spectrum beta-lactams including carbapenems.     

The integrin ligand echistatin prevents bone loss in ovariectomized mice and rats

Integrins that bind RGD (arginine-glycine-aspartic acid) containing peptides, especially the vitronectin receptor alpha(v)beta3, have been implicated in the regulation of osteoclast function. Echistatin, an RGD-containing snake venom peptide with high affinity for beta3 integrins, as well as nonpeptide RGD mimetics, were shown to inhibit osteoclastic bone resorption in vitro and in vivo. To evaluate the role of RGD-binding integrins in bone metabolism, we examined by several methods the effects of echistatin on ovariectomy (OVX)-induced bone loss in mice and rats. First, we confirmed that echistatin binds in vitro with high affinity (Kd, 0.5 nM) to alpha(v)beta3 integrin purified from human placenta and established a competitive binding assay to measure echistatin concentrations in serum. We find that echistatin infused for 2 or 4 weeks at 0.36 microg/h x g body weight (approximately 50 nmol/day x mouse) completely prevents OVX-induced cancellous bone loss in the distal femora of ovariectomized mice. Echistatin has no effect on uterine weight, body weight, and femoral length changes induced by OVX, nor does it cause any apparent changes in major organs other than bone. In OVX rats, echistatin infusion at 0.26 microg/h x g for 4 weeks effectively prevents bone loss, evaluated by dual energy x-ray absorptiometry of the femur, by femoral ash weight, and by bone histomorphometry of the proximal tibia. At effective serum concentrations of 20-30 nM, measured at the end of the infusion period, echistatin maintains histomorphometric indices of bone turnover at control levels but does not decrease osteoclast surface. In conclusion, these results provide in vivo evidence, at the level of bone histology, that RGD-binding integrins, probably alpha(v)beta3, play a rate-limiting role in osteoclastic bone resorption and suggest a therapeutic potential for integrin ligands in the suppression of bone loss.     

Expression of laminin in renal-cell carcinomas, renal-cell carcinoma cell lines and xenografts in nude mice

We studied the expression of laminin (Ln) chains (alpha1-alpha3, beta1-beta3, gamma1) in human renal-cell carcinomas (RCC), papillary renal neoplasms (PRN) and oncocytomas, in RCC cell lines and their xenografts. In RCCs the basement membranes (BM) showed immunoreactivity for chains of Ln-1 (alpha1-beta1-gamma1). Only in well-differentiated RCCs could vessel BMs be distinguished from those of carcinoma cell islets. RCCs and oncocytomas also exhibited an abundant immunoreactivity for Ln beta2 chain in both vessel and tumor cell BMs, while Ln alpha2 chain was not seen in any renal tumors. In distinction from RCCs, PRNs presented a strong BM immunoreactivity for Ln alpha3 and beta3 chains and for Ln-5, as well as lack of Ln beta2 chain. A more variable reactivity for Ln-5 was seen in oncocytomas. As PRNs and oncocytomas have been suggested to originate from collecting ducts, it is notable that in normal human kidney, we could detect immunoreactivity for Ln-5 and its chains only in BM of the tubules of the loop of Henle. In immunoprecipitation experiments, an abundant production of Ln-1, but not of Ln-5, was seen in cultured RCC cells, while in xenografts of the same cells BM-confined immunoreactivity for both Ln-1 and Ln-5 was seen. Ln beta2 chain was produced by 2 of the 4 RCC cell lines in culture but was found only in 1 of the xenografted tumors.     

Kinetics of cell division in peripheral blood lymphocytes of stainless steel welders]

The management of fracture within previously shortened extremity is presented. Three patients with femoral fracture and one with crural fracture were treated. All fractures were displaced. Modified Ilizarov ring distractor was used to stabilize the fracture within 3 days from injury. Distraction was commenced on third postoperative day at speed of 0.75-2 mm/h with progressive reduction of fragments and alignment of mechanical axis of the limb. Lengthening required to equalize extremities was achieved in all cases. The author claims fracture within previously shortened extremity to be one more indication for external osteosynthesis as a method of choice.     

The effect of tricyclic antidepressants and neuroleptics on the peripheral and central action of norepinephrine in reserpine-treated mice

The effect of exogenous norepinephrine on the ptosis induced by reserpine and its modification by tricyclic antidepressants and neuroleptics were studied in reserpine-pretreated mice. S.c injection of norepinephrine (0.3-5 mg/kg) reversed dose-dependently the ptosis induced by reserpine. The maximal effect was obtained 15 min after norepinephrine administration. Tricyclic antidepressants (2.5 and 5 mg/kg i.p.) potentiated the effect of norepinephrine. In contrast neuroleptics (1 and 5 mg/kg i.p.) antagonized it. Intracerebral injection of norepinephrine (5-20 mug) also reversed dose-dependently the ptosis induced by reserpine, and the maximal effect was obtained within 5 min. Tricyclic antidepressants potentiated the effect of norepinephrine, but neuroleptics antagonized it. Among tricyclic antidepressants, the potentiating action of secondary amines was stronger than that of tertiary amines. Chlorpromazine blocked the action of norepinephrine more strongly than did the same dose of haloperidol.     

Analysis of in vivo cell proliferation of ATL using SCID mice

We made a model of in vivo cell proliferation of leukemic cells from adult T cell leukemia (ATL) patients using severe combined immunodeficient (SCID) mice. SCID mice injected with ATL cells from 6 of 8 ATL patients were found to have the tumor. DNA analysis revealed that the clone of the cells proliferating in mice was the same as that of the original leukemic cells. Histologic examination showed that the pattern of the infiltration of ATL cells in mice was similar to that of an ATL patient. Next, we examined the tumorigenicity of HTLV-I infected cell lines using SCID mice. Seven HTLV-I infected cell lines were injected into SCID mice and it was found that 4 of them were capable of proliferating in SCID mice. HTLV-I infected cell lines of non-leukemic cell origin could not engraft in SCID mice, indicating that these cells seemed not to have the enough genetic changes to acquire the tumorigenic potential. Analysis of gene expression suggested that neither IL-2 nor HTLV-I viral product was directly involved in the neoplastic cell growth of ATL. Furthermore, T cells immortalized by introduction of Tax could not engraft in SCID mice, indicating that the expression of tax gene seemed not to be sufficient for the neoplastic cell growth in vivo.     

Antinociceptive activity of metamizol in rats with experimental ureteric calculosis: central and peripheral components

OBJECTIVE AND DESIGN: To study the antinociceptive effects of metamizol in a rat model of ureteric calculosis. Subjects: Adult female Wistar rats (n = 40). TREATMENT: Metamizol was given i.p. 50-100 mg/kg, 3 times daily for 4 days for behavioural testing, and 25-100 mg/kg i.v. whilst recording peristalsis or dorsal horn neurons. METHODS: An artificial stone was induced in one ureter. In 3 separate groups of stone-implanted rats, behaviour was recorded continuously on video tape, ureteric peristalsis or the electrical activity of single nociceptive dorsal horn neurons with ureteric input was recorded under anaesthesia. Data were compared with analysis of variance. RESULTS: Metamizol inhibited the behavioural visceral crises, the abnormal ureteric peristalsis and the activity of nociceptive dorsal horn neurons. CONCLUSIONS: Metamizol has central antinociceptive effects on the pain produced by a ureteric stone, and an additional spasmolytic effect on the hyperperistalsis produced by the stone.     

Changes in the central and peripheral serotonergic system in rats exposed to water-immersion restrained stress and nicotine administration

The effects of water-immersion restraint stress (WS) on chronically nicotine-administered rats were studied in the blood and various regions of the brain. Serotonin (5-HT) levels increased in the hypothalamus, hippocampus, cortex and cerebellum following the administration of nicotine. 5-HT levels increased in all the brain regions following stress. Nicotine decreased stress-induced increased levels of 5-HT in the hippocampus and cerebellum. Nicotine administration alone increased 5-hydroxyindole acetic acid (5-HIAA) levels in the hippocampus and cerebellum. Stress alone also increased 5-HIAA levels in all the brain regions. In the cortex, 5-HT and 5-HIAA levels further increased following the administration of a combination of stress and nicotine compared to rats given stress alone. In the blood as well as in all the brain regions, except the cerebellum, stress or nicotine administration did not affect tryptophan levels. Stress given to nicotine-administered rats resulted in a decrease in tryptophan levels in the blood and plasma. Although 5-HT and 5-HIAA levels were not influenced by stress and/or nicotine administration, the 5-HIAA/5-HT ratio increased in the blood and plasma of rats administered with nicotine and exposed to stress. The effects of nicotine on the serotonergic system depend upon the kind of stress given together with the organs and brain regions involved.     

Early weaning induces jejunal ornithine decarboxylase and cell proliferation in neonatal rats

Increased ornithine decarboxylase (ODC) activity is associated with rapid cell proliferation in many cell types. The cellular effects of early weaning on intestinal development are not well established. To investigate whether ODC is involved in intestinal growth after early weaning, we precociously weaned suckling rats on postnatal d 15 and followed through d 21 (6 d after early weaning). Age-matched suckling pups served as controls. Rat pups were killed 1, 2, 3 and 6 d after early weaning and jejunal mucosa was assayed for ODC and sucrase activities, and protein and DNA contents. Jejunal cell proliferation was monitored by bromodeoxyuridine immunohistochemistry. Elevated jejunal ODC activity 1 d after early weaning was the earliest cellular event that was detected in the current study. ODC activity peaked at d 3 (about 15-fold greater than age-matched unweaned suckling controls). Sucrase activity was elevated at d 2 after weaning and peaked at d 3 (about 10-fold greater than controls). Greater bromodeoxyuridine immunostaining in early weaned rats occurred on d 3. Protein and DNA contents were greater in jejunal mucosa of early weaned rats at d 6. Serum corticosterone levels were elevated on d 1 and d 2 after early weaning compared to controls. To explore whether the intake of nonpurified diet played a role, we also compared the induction of jejunal ODC activity in early weaned pups and pups that were food-deprived for 1 d. ODC activity was not greater in the food-deprived group compared to suckling controls while the early weaned group had 6-fold greater activity 1 d after early weaning. Early weaning stimulates jejunal cell proliferation and differentiation. The temporal sequence of increased ODC activity followed by increases in other growth variables suggests that the induction of ODC activity may act as an early marker of intestinal growth during early weaning.