Phenolate-bridged A2B-type subporphyrin dimer

An ether cleavage reaction of A2B-type subporphyrin bearing an ortho-anisyl substituent afforded a phenolate-bridged dimer. A head-to-tail structure of the dimer was unambiguously elucidated by single crystal X-ray diffraction analysis. UV-vis absorption and magnetic circular dichroism spectra indicated a minor interaction between the subporphyrin chromophores. Density functional theory calculations provided a detailed insight into the electronic structures of the subporphyrin dimer.

Neurobehavioral Differences Between Mice Receiving Distinct Neuregulin Variants as Neonates; Impact on Sensitivity to MK-801

Neuregulin-1 (NRG1) is a well-recognized risk gene for schizophrenia and is often implicated in the neurodevelopmental hypothesis of this illness. Alternative splicing and proteolytic processing of the NRG1 gene produce more than 30 structural variants; however, the neuropathological roles of individual variants remain to be characterized. On the basis of the neurodevelopmental hypothesis of schizophrenia, we administered eNRG1 (0.1~1.0 μg/g), a core epidermal growth factor-like (EGF) domain common for all splicing NRG1 variants, to neonatal mice and compared their behavioral performance with mice challenged with a full mature form of type 1 NRG1 variant. During the neonatal stage, recombinant eNRG1 protein administrated from the periphery passed the blood-brain barrier and activated its receptor (ErbB4) in the brain. In adults, the mice receiving the highest dose exhibited lower locomotor activity and deficits in prepulse inhibition and tonedependent fear learning, although the hearing reduction of the eNRG1-treated mice may explain these behavioral deficits. Neonatal eNRG1 treatment also significantly potentiated MK-801-driven locomotor activity in an eNRG1 dose-dependent manner. In parallel eNRG1 treatment enhanced MK-801-driven c-Fos induction and decreased immunoreactivity for NMDA receptor subunits in adult brain. In contrast, mice that had been treated with the same molar dose of a full mature form of type 1 NRG1 as neonates did not exhibit hypersensitivity to MK-801. However, both animal models exhibited similar hypersensitivity to methamphetamine. Collectively, our findings suggest that aberrant peripheral NRG1 signals during neurodevelopment alter later behavioral traits and auditory functions in the NRG1 subtype-dependent manner.

Unexpected formation of a triphyrin in the reaction of dibromodipyrromethene and N,N-dimethylaminoethanol

A novel triphyrin was unexpectedly formed as a major by-product in the synthesis of meso-aryl-substituted dibenzo-5,10,15-triazaporphyrin from meso-aryl-substituted 1,9-dibromodipyrromethene and 5,6-diaryl-substituted 1,3-diiminoisoindoline in the presence of N,N-dimethylaminoethanol (DMAE). X-ray single crystal diffraction analysis elucidated that the terminal α-positions of this triphyrin were bridged by an N-methylaminoethoxy chain, which plausibly originated from DMAE during the reaction. The same compound was also obtained as a major product in the reaction of DMAE and meso-aryl-substituted 1,9-dibromodipyrromethene. Its unique properties, such as conformational flexibility of the bridging moiety and broad absorption in the visible region, were also revealed by 1 H NMR and UV-vis absorption spectroscopies.

Immunomodulating activities of polysaccharide fractions from dried safflower petals

In the course of screening for immunomodulators, we found a significant blastogenic activity specific for splenic B cells in the extracts of safflower (Carthamus tinctorius L.). Active fractions termed SF1 and SF2 were purified from dried petals of safflower by boiling water extraction, ethanol precipitation and Sepharose CL-2B column chromatography. The elution profiles of the gel filtration indicated that the molecular weight of SF1 and SF2 was estimated to be more than 100 kD. Major components of SF1 and SF2 seem to be polysaccharides, and structural analysis of alditol acetate derivatives by GC-MS revealed some differences between SF1 and SF2 in the sugar component. Biological activities of SF1 and SF2 on B cells and macrophages were examined in comparison with lipopolysaccharides (LPS). SF1 and SF2 induced both the proliferation and the IgM production of B cells to the equivalent level as those induced by LPS. In macrophages, SF1 and SF2 effectively stimulated the production of NO. However, SF1 stimulated the production of IL-1, IL-6, and TNF as much as LPS, while SF2 induced them only weakly or not at all. Thus, these results suggest that SF1 and SF2 activate B cells and macrophages in different mechanisms.

Risk factors for the progression of endoscopic Barrett's epithelium in Japan: a multivariate analysis based on the Prague C & M Criteria

PURPOSE

To determine the prevalence and progression of Barrett's epithelium and associated risk factors in Japan.

METHODS

The study population comprised 869 cases. Endoscopic Barrett's epithelium was diagnosed based on the Prague C & M Criteria. The correlations of clinical factors with the prevalence and progression of endoscopic Barrett's epithelium were examined.

RESULTS

Endoscopic Barrett's epithelium was diagnosed in 374 cases (43%), in the majority of which the diagnosis was short-segment Barrett's esophagus. The progression of Barrett's epithelium was identified in 47 cases. In univariate and multiple logistic regression analyses, aging, smoking habit, and erosive esophagitis were significantly associated with the prevalence of Barrett's epithelium, whereas aging and erosive esophagitis, especially severe erosive esophagitis, were significant contributing factors to the progression of Barrett's epithelium.

CONCLUSIONS

Forty-three percent of the total study population was diagnosed as having endoscopic Barrett's epithelium. During the follow-up period, 12.6% of the cases with Barrett's epithelium exhibited progression which was associated with aging and severe erosive esophagitis.

A phase II study of S-1 in gemcitabine-refractory metastatic pancreatic cancer

4115

Background: Gemcitabine (Gem) monotherapy or Gem-containing chemotherapy is the standard first line therapy for advanced pancreatic cancer. After disease progression, there is no standard regimen available. In a previous phase II trial (J. Furuse et al, Proc ASCO 2005: # 4104), S-1 has been reported to show considerable efficacy, achieving a response rate of 37.5% in chemo-naïve patients with pancreatic cancer. This study evaluated the efficacy and toxicity of S-1 in patients with Gem-refractory metastatic pancreatic cancer. Methods: Eligibility criteria were pathologically-proven pancreatic cancer with confirmation of progressive disease while receiving Gem-based chemotherapy, Karnofsky performance status 80 to 100%, age 20 to 74 years, with measurable metastatic lesions, adequate hematological, renal and liver functions, and written informed consent. S-1 was administered orally at 40 mg/m2 twice daily for 28 days with a rest period of 14 days as one course. Administration was repeated until the appearance of disease progression or unacceptable toxicity. The primary study end point was objective response, secondary end points included toxicity, progression-free survival (PFS) and overall survival, as well as clinical benefit response in symptomatic patients. Results: Forty patients (pts) from two institutions were enrolled between September 2004 and November 2005. Thirty-three pts are currently evaluable for response in this ongoing trial. There have been 5 confirmed partial responses (12.5%), and 14 pts (35%) with stable disease. Median survival has not been reached. Median PFS was 2.1 months. Toxicity data were available for 28 patients. Grade 3 and 4 toxicities were anemia (1 pts), appetite loss (2 pts), and fatigue (2 pts). Conclusions: Preliminary results demonstrated the safety and activity of S-1 in Gem-refractory metastatic pancreatic cancer. Efficacy and toxicity analysis are ongoing. Final results will be presented at the meeting.

No significant financial relationships to disclose.

A case of body stalk anomaly arising in the second baby of a triplet pregnancy after in-vitro fertilization and embryo transfer

We report a case of body stalk anomaly arising in the second baby of a triplet pregnancy after in-vitro fertilization and embryo transfer (IVF-ET). Body stalk anomaly or limb-body wall complex is a rare congenital anomaly with a series of similar clinical manifestations and poor prognosis. IVF-ET is an effective treatment for various types of infertility. We summarize and discuss herein the relation with the sequence of genesis for such malformations and multiple pregnancies after IVF-ET.

Ileoileal intussusception and ileal stricture associated with necrotizing enterocolitis in a premature infant: report of a case

A 630-g male infant developed presumed necrotizing enterocolitis (NEC) after fungal enteritis that resulted in subsequent fungal septicemia associated with pneumoperitoneum on the 9th day of life. Urgent percutaneous Penrose drainage was required. During the operation on the 14th day, an ileoileal intussusception and an ileal stricture were found with perforations on each oral side of the lesions. The distinction between NEC and intussusception in premature infants when they coexist can be difficult, as these conditions share common symptoms. The relation between ischemic injury and dysmotility of the intestine is also discussed. The similarity of intrauterine fetal distress and NEC in premature infants, as seen in the present case of the intussusception associated with focal NEC, suggests that mesenteric and enteric vascular ischemia could be one trigger of intussusception in neonates.

Non-Hodgkin's lymphoma of the ascending colon in a patient with becker muscular dystrophy: report of a case

We herein present the findings of a 10-year-old boy with non-Hodgkin's lymphoma of the ascending colon which caused intussusception and intestinal bleeding. He had a history of Becker muscular dystrophy. However, he had neither hypertrophic calves nor cardiomyopathy, and his serum creatine kinase (CK) level always exceeded 2000 IU/l. Preoperatively, a laboratory examination revealed high serum levels of CK (2038IU/l), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH), and the blood hemoglobin level was 7.0g/dl. A barium enema examination revealed an intussusception in his ascending colon, which was found to be a highly vascular tumor on Doppler ultrasound scans. A right hemicolectomy was performed. Macroscopically, the 5 x 6 x 8-cm solid tumor of the ascending colon resembled a submucosal tumor and had two ulcerous lesions at the tip. The tumor was histologically diagnosed to be a diffuse large B-cell lymphoma of the ascending colon. General examinations revealed no involvement of lymphoma postoperatively. At 13 months after surgery, the CK (37861U/l), AST (110lU/l), ALT (1381U/ l), and LDH (420lU/l) levels are still high, and the patient is doing well without any signs of recurrence.

Circumferential measurement and analysis of strain distribution in the human ACL using a photoelastic coating method

Large variable deformations of the ligament cannot be adequately quantified by one-dimensional and/or localized measurements. To obtain accurate measurement of non-uniform strains over the entire surface of anterior cruciate ligament (ACL), we used a photoelastic coating technique and a method that allowed us to photograph an ACL around its longitudinal axis. A cadaver knee was modified to expose its ACL for observation, and the ligament was then coated with a photoelastic material. The knee was locked in a jig that allowed simulation of natural knee motion. The jig containing the knee was then mounted on a stand, which allowed the exposed ACL to be photographed from any angle around its longitudinal axis while set at a chosen degree of knee flexion. The jig itself was rotated on its stand so as to obtain a panoramic view of the ACL at a given knee angle. The obtained images of the photoelastic fringe patterns yielded significant information for understanding how the strain distributions along the fiber bundles change in association with knee motion. From the results we obtained using the photoelastic measuring method, we reached the following conclusions. Reciprocal functioning between the anterior and the posterior bundles from extension to flexion of the knee does occur. Strain distribution is not uniform even along the same bundle. The strain behavior of the ACL under uniaxial tensile test does not duplicate the conditions in which the ACL is damaged during knee motion. The differences in strains on the ACL under active and passive knee motions may not be as large as those reported previously in the literature.

Three-dimensional deformation and stress distribution in an analytical/computational model of the anterior cruciate ligament

In this study, a constitutive equation for the ACL composite was formulated, and 3-D finite deformations and stress distributions of the ACL were calculated using a finite element method to simulate knee flexion. The mathematical model of the ACL was created by a structurally motivated phenomenological approach. It was assumed that the ACL can be ideally represented as a homogeneous hyperelastic matrix (Mooney-Rivin material) in which two families of densely distributed extensible fibers are embedded; the fibers in one family have a parallel orientation, the other fibers extend radially in eight equally spaced directions. The non-linear stress-strain characteristic exhibited by collagen fibers was represented by a tri-linear curve. Simulation was performed and the results provided some original data; the stress distribution within the ACL body as well as that over the surface, the 3-D deformations and stress distributions of the ACL viewed from other sides in addition to those from the medial side, and the variations of the stress distribution pattern in the ACL which occurred when the tibia was displaced anteriorly or posteriorly.

Analysis of strain distribution in the medial collateral ligament using a photoelastic coating method

The strain distribution over the entire medial collateral ligament (MCL) was measured using a photoelastic coating method. This new approach utilized a polyurethane monomer as a photoelastic coating film. The initial experiments investigating MCL strain measurement showed that this film had a high sensitivity for strain and good adhesion to the ligament. It was confirmed that strain distribution could be obtained qualitatively over the entire ligament using this method. The mechanism of MCL injury was studied by applying this polyurethane coating film to the entire MCL in a femur-MCL-tibia complex. When simple tension was applied to the complex, strain concentrations were centred at the tibial insertion site, and all the specimens ruptured at the MCL tibial insertion site. With application of a valgus bending moment, increased strain was seen in the MCL from the medial femoral condyle to the medial epicondyle. Histological analysis demonstrated midsubstance ligament ruptures in this same region. For both tests, rupture sites and increased strain concentration sites correlated. In addition, an impingement phenomenon of the MCL on the medial femoral condyle can be seen during application of valgus force, and this phenomenon may explain the higher incidence of MCL injuries on the femoral side seen in the clinical setting. This polyurethane coating method allows for direct and visual measurements, and can qualitatively measure the strain behaviour over the entire MCL surface. This new technique represents a significant improvement over previous point-by-point strain measurement methods.

A photoelastic study of ligament strain

The anterior cruciate ligament (ACL) in the human knee is known to exhibit as large as 10-20% of strain in association with knee flexion, while usual Hookean elastic materials exhibit at most 0.3%. Furthermore the complex ACL in shape deforms in highly variable manners due to the complicated three-dimensional (3-D) movements of the insertions in association with knee flexion. Such large and highly variable deformations of the ACL cannot be adequately quantified by one-dimensional (1-D) and/or localized measurements. In order to measure strains over the entire area of the ACL, we employed the photoelastic coating method to analyze stress on the basis of the strains. A specific kind of polyurethane possessing optically high fringe-sensitivity was found to be most suitable for measurement purposes. From the preliminary experiments, it was found that a linear relation with 99% of correlation coefficient between the birefringence order and the strain on the polyurethane film continued up to 45% of strain. This study was done in two steps. In the first step, a study was done using a unique model of a knee joint fabricated in a way which allowed deformation and strain distribution in the model ACL to be directly observed and measured by means of the photoelastic coating method. It was confirmed that the film, having negligible effect on the mechanical properties of some biological soft tissues, closely reflected the strain behavior of the tissue. Thus in the second step, the photoelastic method was employed to measure the strains on an actual ACL during free flexion-extension of the knee. A specially designed apparatus was used to allow a natural motion of the knee. The photoelastic measurements demonstrated the potential utility of the application to measuring strain distributions not only on a model ligament but also on an actual ligament. The measurement of an actual ACL led the following results; The principal strain lines well depicted its fiber directions. A reciprocal function between the anterior and posterior bundles was observed. And there was a zero-strain area on the central and posterior sides near the tibial insertion.

Neuroblastoma in an adult with a high serum level of carbohydrate antigen, CA125: report of a case

We report herein the case of a 56-year-old woman with a neuroblastoma associated with a high serum level of carbohydrate antigen, CA125. The patient presented with massive ascites and a firm mass in her upper abdomen for which a laparotomy was performed. However, a recurrent tumor was found 6 months later and she died of the disease within 1 year of surgery despite several courses of adjuvant chemotherapy. Neuroblastoma rarely occurs in adults, and the features of 58 adult cases described in the world literature is summarized following the presentation of the clinical data on this case. The distribution of primary sites in adults is dispersed compared to that seen in pediatric cases, while the natural history of the disease in adults may be longer and less sensitive to chemotherapy than in children. The survival rate of adults with this disease is poor. We conclude that aggressive surgical intervention combined with appropriate chemotherapy protocols as applied in children should be performed in an attempt to achieve complete remission and improve the survival rate of adults with neuroblastoma.

Strain distribution in the ligament using photoelasticity. A direct application to the human ACL

Large and highly variable deformations of the anterior cruciate ligament (ACL) in the human knee cannot be adequately quantified by one-dimensional and/or localized measurements. In order to measure strains in the entire area of the ACL, we employed the photoelastic coating method to analyze stress on the basis of the strains. A specific kind of polyurethane possessing optically high fringe-sensitivity was found to be most suitable for the measurement purposes. Although the photoelastic method has been successfully applied in various fields for stress analyses, its use in studying large deformations of biological tissues has not been reported. Therefore, before proceeding with our main study, we first examined the effects of polyurethane film on the mechanical properties of the ligament. We found that the film had a negligible effect on the tissues' properties, and closely reflected the strain behavior of the tissues. We then applied the method to measure strains on an actual ACL during free flexion-extension of the knee. A specially designed apparatus was used to allow a natural motion of the knee. A portion of the femoral bone was removed to expose the ACL to view. Measurement and analysis gave continuous information about strain distribution, including the variations of strain along the principal strain directions in the ACL.

Hyper-elastic model analysis of anterior cruciate ligament

The objectives of this study were to theoretically analyze changes in shape and stress distribution which occur over the entire surface of the anterior cruciate ligament (ACL). While many studies on the cruciate ligaments' tensile characteristics have been conducted, the length patterns and the differential function of the ACL are still controversial issues for two reasons. Highly variable deformations of the ligaments (which are not uniaxial structures such as a bundle of separate fibres) cannot be adequately quantified by one-dimensional and/or localized measurements. Furthermore, it is impossible to directly measure in situ, non-uniform distribution of biaxial strain over the entire surface of the intra-articular ligaments. We employed an alternative approach which may have the potential to solve some of these difficulties. Using the finite element method, in which the ligament was treated as an incompressive hyper-elastic membrane, the finite deformation of the ligament was theoretically analyzed. Boundary conditions were applied by prescribing the displacements at the boundary nodes corresponding to the insertions. Special attention was paid to the distribution of longitudinal strain. The following values were obtained as a function of knee flexion: three-dimensional change in shape and strain distribution, length change of each fibre, length changes in positions along a fibre, resultant pull force on the tibial insertion, and change of strain pattern by anterior-posterior displacement of the tibia. The results demonstrated that strain distribution varied, even along the fibre run, and large strain gradients were observed in the regions near the insertions. It was found that distance between insertions introduced noticeable discrepancies from the length along a curved fibre. The net resultant force at the tibial insertion of the ligament was maximum at 0 degree of flexion, decreased until 50 degrees of flexion, then slightly increased up to 120 degrees of flexion. Predominantly, the anterior and the posterior displacements of the tibia, respectively, increased and decreased strain in the ligament, however, some portions were even more stretched by the posterior displacement.

Energy expenditure and fatiguability in paraplegic ambulation using reciprocating gait orthosis and electric stimulation

To clarify the relationship between metabolic energy expenditure and fatiguability in paraplegic persons fitted with orthoses, we measured energy consumption in six thoracic paraplegic patients ambulating by means of reciprocating gait orthosis (RGO) used with and without functional electrical stimulation (FES). The data obtained from persons using both RGO and FES were adjusted to allow for the effects of fatiguability so as to obtain an approximate value for upper-body consumption. The data obtained from persons using RGO only were not adjusted, because no energy consumption occurred in the lower portion of the body. The data, expressed in kcal/kg-min and kcal/kg-m, were plotted against walking speed attained using RGO, and RGO with FES. The results were compared with those from persons fitted with long leg braces (LLB), hip guidance orthoses (HGO) and an FES walking aid (data obtained from available literature). We found that the lowest energy expenditure in kcal/kg-m across the full range of walking speeds occurred when both RGO and FES were used together, followed by RGO only, HGO, LLB, and FES only, respectively. The lowest energy expenditure in kcal/kg-min, for walking speeds, below 0-28 m/s, also occurred when both RGO and FES were used together, followed by RGO only, HGO, LLB, and FES only. The results suggest that, although the use of FES with RGO may increase oxygen uptake, it decreases energy expenditure in the upper extremities, thereby reducing patient fatigue. They also suggest that mechanical orthosis giving passive support to the hip, knee and ankle in combination with FES may provide the most efficient walking aid for paraplegic persons.

Effect of Hachimi-jio-gan on scopolamine-induced memory impairment and on acetylcholine content in rat brain

The effect of Hachimi-jio-gan (HJ) on scopolamine induced memory impairment was studied using a radial maze performance, the effect of HJ on the central cholinergic system as measured by acetylcholine (ACh) content, choline acetyltransferase (CAT) and acetylcholinesterase (AChE) activities was also examined. HJ (0.01-1.0 g/kg, p.o.) showed no influence on the radial maze performance. However, with the administration of scopolamine (0.5 mg/kg, i.p.), the number of the correct choices decreased and the number of the error choices increased. HJ (0.1 and 0.5 g/kg, p.o.) reduced this scopolamine-induced cognitive disturbance. The effect of HJ on ACh content and enzyme activities in the brain, frontal cortex, hippocampus and striatum was also investigated. In normal rats, HJ (0.1 and 0.5 g/kg, p.o. x 7 days) significantly increased ACh content in the frontal cortex, although it did not increased ACh content in the hippocampus. In scopolamine-treated rats, ACh content decreased in the brain regions examined. HJ (0.5 g/kg, p.o.) inhibited a decrease in ACh content in the frontal cortex, and with the same dosage of HJ increased CAT activity in the frontal cortex and AChE activity in the hippocampus. These results suggest that the behavioral effects of HJ may be related to its effect on the central cholinergic system.

Anabolic-androgenic steroid abuse in weight lifters: evidence for activation of the hemostatic system

Anabolic-androgenic steroid abuse has recently been linked with acute vascular events in athletes. To date, the relationship between steroid abuse and the potential for cardiovascular disease has been considered almost exclusively in terms of lipid metabolism. However, recent reports of thrombosis in androgen abusing athletes with no evidence of atherosclerosis suggests the hypothesis that thrombosis risk in such athletes could be mediated through androgen induced abnormalities of coagulation. To determine if anabolic-androgenic steroid abuse in weight lifters is associated with an activation of the hemostatic system we studied forty-nine weight lifters recruited through advertisements. History of androgen use or abstinence was confirmed via urine assays. Plasma was assayed for clotting and fibrinolytic activity by measuring thrombin/antithrombin complexes (TAT), prothrombin fragment 1 + 1 (F1 + 2), and D-dimers (D-di); markers of the endothelial based fibrinolytic components were assayed by measuring tissue plasminogen activator antigen (t-PA Ag) and its inhibitor (PAI-1); finally, the activity of antithrombin III, protein C, and protein S were measured. Abnormally high concentrations of TAT complexes were noted in 16% of our confirmed steroid using weight lifters compared to 6% of our confirmed nonusers (P = .01). Steroid users also demonstrated abnormally high concentrations of F1 + 2 and D-dimers when compared to nonusers (44 vs. 24%, P < .001, and 9 vs. 0%, respectively). Non-steroid users were more likely to have elevated levels of t-PA Ag and PAI-1 than our steroid using weight lifters (both P < .001). The activities of antithrombin III and protein S were more likely to be higher in users compared to nonusers (22 vs. 6%, P = .005; 19 vs. 0%, respectively). Some anabolic-androgenic steroid using weight lifters have an accelerated activation of their hemostatic system as evidence by increased generation of both thrombin and plasmin. These changes could reflect a thrombotic diatheses that may contribute to vascular occlusion reported in young athletes using these drugs. The predictive value of these coagulation abnormalities in terms of risk of thrombosis to individual steroid using weight lifters or the population as a whole remains to be studied.

Effect of hachimijiogan, an oriental herbal medicinal mixture, on experimental amnesia in mice

The effect of Hachimijiogan on cognitive disturbance was investigated using step-through passive avoidance failure techniques: scopolamine-, cycloheximide- and cerebral ischemia-induced amnesia. Pre-acquisition trial administration of Hachimijiogan (0.5 g/kg, p.o.) prolonged the step-through latency reduced by scopolamine and cycloheximide. Hachimijiogan (0.5 and 1.0 g/kg, p.o.) also ameliorated the cerebral ischemia-induced amnesia. Physostigmine (0.1 mg/kg, i.p.) ameliorated all three amnesia models. The ameliorating effects of Hachimijiogan and physostigmine on cycloheximide-induced amnesia were diminished by the combination with scopolamine. These results suggest that Hachimijiogan possesses a wide-ranging pharmacological profile in anti-amnesic actions and that its anti-amnesic activities may be related to the cholinergic neuronal system.

Protective effect of hachimi-jio-gan, an oriental herbal medicinal mixture, against cerebral anoxia

The protective effect of Hachimi-jio-gan (HJ) against cerebral anoxia was investigated with various experimental models in mice. Minimal effective dose of HJ which significantly prolonged the survival time was 0.5 g/kg, p.o. for normobaric hypoxia and 0.5 g/kg, p.o. for KCN- (4 mg/kg, i.v.) induced anoxia. HJ reduced the duration of coma induced by a sublethal dose of KCN (1.8 mg/kg, i.v.) in a dose-dependent manner. Furthermore HJ potentiated the anti-anoxic effect of physostigmine and the effect of HJ was diminished by the treatment with atropine.

Thrombosis and hormone replacement therapy in postmenopausal women

OBJECTIVE

The effects of postmenopausal hormone replacement therapy on thrombosis remain controversial. We tested the hypothesis that estrogen or progesterone has no significant effect on thrombosis by means of newly developed markers of blood clotting, specifically prothrombin fragment 1 + 2, a marker of factor Xa generation, and thrombin-antithrombin III complex, a marker of thrombin generation.

STUDY DESIGN

A prospective study that included 106 women, 68 postmenopausal women on hormone replacement therapy and 38 postmenopausal controls, was performed. Plasma levels of prothrombin fragment 1 + 2 and thrombin-antithrombin III complex were measured by enzyme-linked immunosorbent assay. Multivariate analysis of the covariance was used for statistical analysis, controlling for patient's age because the hormone replacement therapy group was older.

RESULTS

There were no statistically significant differences between the hormone replacement therapy and control groups in either of the clotting parameters measured. A comparison of the levels of prothrombin fragment 1 + 2 and thrombin-antithrombin III complex in patients receiving estrogen alone or estrogen plus progestin also revealed no differences.

CONCLUSIONS

Current doses of postmenopausal hormone replacement therapy do not appear to enhance in vivo clotting. Thromboembolic complications among postmenopausal women receiving hormone replacement therapy may therefore be secondary to congenital or other acquired coagulation defects.

Effects of variation on extensor elements and operative procedures in patellofemoral disorders

The influence of both insertion and strength/elasticity of each extensor in patellofemoral disorders was fully investigated through a two-dimensional mathematical model analysis in a horizontal plane, in combination with experimental design theory for analyzing mutually correlated influences. In the model, patellofemoral joint profiles projected on a horizontal plane have been expressed as spline functions. Each muscle of the quadriceps has been represented as a string pulled by the respective force; fascias and tendons have been represented by springs. Nonlinear equations have been constructed to represent the forces involved, and then solved by numerical iteration. An analysis of variance was performed on the data derived from a series of simulations, obtaining the following results. The strength of most extensors has been shown to have an influence on the increase in lateral contact force but not patellar translation. The tibial tubercle position has significant influence on both patellar translation and lateral contact force. The quadriceps' insertion on the femur has no influence on patellar translation. The insertion of each extensor on the patella has been shown to have a strong effect on patellar translation but not on contact force.

Anterior-posterior and rotational displacement of the tibia elicited by quadriceps contraction

The anterior-posterior displacement and rotation of the tibia elicited by isolated loading of the quadriceps muscle was determined as a function of joint angle and muscle load using a computerized radiographic technique. Data collected from 12 fresh-frozen cadaveric knees demonstrated that quadriceps contraction can result in significant (less than 7 mm) anterior displacement of the tibia in the range of 0 degrees to 80 degrees of flexion, and a mild (less than 2 mm) posterior displacement in the range of 80 degrees to 120 degrees of flexion. Peak anterior displacement of 6.3 mm was observed at 30 degrees of flexion under a 12 kg load in the quadriceps, while a constant 1.5 mm posterior displacement was observed throughout flexion angles exceeding 80 degrees. It was further shown that the magnitude of the anterior displacement increased nonlinearly as the quadriceps force increased. Loading of the quadriceps also resulted in internal rotation of the tibia in the range of 0 degrees to 90 degrees of flexion, and in external rotation of the tibia in the range of 90 degrees to 120 degrees. Peak internal rotation of 7 degrees was observed at 15 degrees of flexion and a peak external rotation of 1 degrees was detected at 120 degrees of flexion. Larger quadriceps load resulted in larger rotation. We concluded that quadriceps contraction during knee extension has direct impact on anterior displacement and rotation of the tibia and therefore on anterior cruciate ligament stress, increasing it as the muscle's force is increased during knee extension.(ABSTRACT TRUNCATED AT 250 WORDS)

Synergistic stimulating effect between cyclic AMP and phorbol ester on plasminogen activator inhibitor type 2 production in human promyelocytic leukemia cell line PL-21

We investigated the effect of agents which raise intracellular cyclic AMP (cAMP) and protein kinase C activators on the production of plasminogen activator inhibitor type-2 (PAI-2) by cultured human promyelocytic leukemia cell line, PL-21. As previously reported, PMA, a protein kinase C activator, showed a strong stimulating effect on the PAI-2 production. 1-oleoyl-2-acetyl-sn-glycerol (OAG), another synthetic protein kinase C activator, also showed a stimulating effect, which was, however, much less than that of PMA. The agents which raise intracellular cAMP, dibutyryl cAMP, 8-bromo cAMP, prostaglandin E1, and 3-isobutyl-1-methyl-xanthine, little increased the PAI-2 production when tested alone, but showed significant synergistic effects with PMA or OAG. The synergistic effect between PMA and dibutyryl cAMP was further verified by SDS-PAGE followed by immunoblotting using a monoclonal antibody against the PAI-2. It is interesting that the up-regulation of PAI-2 by cAMP and the synergistic effect with PKC activators forms a contrast to the previous reported bi-directional regulation of endothelial PAI-1 secretion by PKC activator and cAMP.

[Activities of antithrombin III and heparin cofactor II in patients with pathologic blood coagulation conditions]

To investigate the physio-pathological functions of HC-II, assays for HC-II and AT-III were performed simultaneously on the samples from patients with DIC, liver dysfunction or renal disease from the three view points of consumption, production and loss of AT-III and HC-II. For the AT-III activity, two kinds of assays were applied: the automatic chromogenic substrate method and a newly developed clotting method which receives no effects from HC-II activity. The activity of HC-II was significantly lower than that of AT-III in patients with either DIC or liver dysfunction. However, no significant difference between HC-II and AT-III activities in patients with either thrombosis or renal disease. There were high correlations between HC-II and AT-III activities were found in the patients with liver dysfunction, suggesting that low activity was due to decreased production of HC-II and AT-III in the liver. It will be necessary that elucidation of the significant functions of HC-II not only in coagulation and hemostasis but also in regulation of local inflammation and invasion of neoplasm is necessary.

The clinical pharmacokinetics of two different preparations of intrarectal ketoprofen following spinal or local anesthesia for anal surgery

Two different preparations of commercially available suppositories containing Ketoprofen (KP) were administered to 49 patients immediately following anal surgery. The KP was prepared as either fatty suppositories (FS) or gelatin capsulated suppositories (GCS) and surgery was performed under either spinal (n = 37) or local anesthesia (n = 12). Similar results were observed in the kinetics of KP after both FS and GCS administration. The extent of bioavailability of the two dosage forms in the patient groups and control subjects (n = 10) were essentially equal. When the pharmacokinetic parameters of KP were compared between patient groups under spinal and local anesthesia, significant differences were found in the values of the peak level (C max), peak time (T max), and terminal phase half-life (t 1/2). The C max decreased by one-half, while the T max and t 1/2 increased twice and four times, respectively, in patient operated on under spinal anesthesia compared to those operated on under local anesthesia. The absorption rate constant (Ka) following spinal anesthesia was significantly less than that following local anesthesia or that of the healthy subjects (p less than 0.01). A "flip-flop" phenomena could be seen in the time profiles of plasma KP concentration following spinal anesthesia.

Three-dimensional mathematical model analysis of the patellofemoral joint

This paper is concerned with a mathematical model analysis of the patellofemoral joint in the human knee, taking into account the articular surface geometry and mechanical properties of the ligament. It was made by the application of a computer-aided design theory (previously studied) and it was possible to express the articular surface geometries in a mathematical formulation and hence elucidate the joint movement mechanics. This method was then applied to a three-dimensional geometrical model of the patellofemoral joint. For the modelling of tendofemoral contact at large angles of knee flexion, the geodestic line theory was adopted. Applying the Newton-Raphson method and the Runge-Kutta Gil method to the model, variables such as patellar attitudes, patellofemoral contact force and tensile force of the patellar ligament for various knee flexion angles were computed. Applying the Hertzian elastic theory, contact stress was also computed. These results showed good agreement with the previously reported experimental results. As an application for the model, some parameter analyses were performed in terms of the contact stress variations and compared with those of the normal knee. The simulation results indicated that both the Q-angle increase and decrease increased contact stress, the patella alta showed undulating variations of stress while the patella infera showed little change of stress, and the tibial tuberositas elevation showed 20-30% reduction of stress.

Energy consumption in paraplegic ambulation using the reciprocating gait orthosis and electric stimulation of the thigh muscles

The energy consumption of six thoracic paraplegic persons ambulating in the reciprocating gait orthosis (RGO) with and without functional electric stimulation (FES) of their thigh muscles was determined as a function of walking speed. Plots of Kcal/kg-min and Kcal/kg-m vs walking speed in the RGO and RGO & FES were experimentally determined in this study and compared with the energy cost of walking in the long leg brace (LLB), the hip guidance orthosis (HGO), and an FES walking aid from data available in the literature. The RGO powered with electric stimulation of the thigh muscles required the lowest energy expenditure in Kcal/kg-m across the full range of walking speeds. The RGO, HGO, LLB, and FES walking orthoses ranked second, third, fourth, and fifth respectively. The lowest energy costs in Kcal/kg-min were associated with the RGO & FES, followed by the RGO, HGO, LLB, and FES for walking speeds below .28m/sec. At walking speeds higher than .28m/sec the HGO demonstrates lower energy cost followed by the RGO & FES, RGO, FES, and LLB. At the end of a 30-m walk, patients using the RGO & FES had a mean heart rate (HR) which was 12 beats/min less than the mean HR when using the RGO without FES, 31 beats/min less than the HR when using the LLB, and 42 beats/min less than the HR when using FES only. It was concluded that the FES-powered RGO combines the advantages of a passive mechanical orthosis with those of FES to provide substantial improvements in energy cost which may provide paraplegic persons with a mode of independent ambulation superior to the wheelchair.

Normal gait characteristics under temporal and distance constraints

Walking patterns of 53 males and 39 females, all in good health, were studied at slow, free, and fast speeds using a walkway system developed by the author. Three males and three females, also in good health, were then studied under constrained walking conditions such as rhythm constraint, speed coupled with constraint, walking up or down a slope, line stepping constraint, stepping onto a marked square, and starting/stopping of walking. In the first set of experiments, the following results were obtained. When increasing speed, the male had a tendency to increase step length and the female had a tendency to increase cadence. The relationships between the speed and the statistics of gait parameters, i.e. the coefficient of variation and the symmetry were examined. The data in this experiment were also applied to Grieve's gait equations which formulated the relationships between step frequency and speed, or between swing time and cycle time. In the second set of experiments the following results were obtained. Although rhythm constraint (induced by a metronome) resulted in no difference of gait between males and females, a difference did appear in the case of speed coupled with constraint. When walking up and down a slope, the ascent case showed a longer step length and a lower cadence compared with the descent. The idea of functional asymmetry, a supporting function of the left leg and a moving function of the right leg, is well accepted. However, in this study of the effect of line stepping constraints predominant right-left functional differences were found.(ABSTRACT TRUNCATED AT 250 WORDS)

The RGO Generation II: muscle stimulation powered orthosis as a practical walking system for thoracic paraplegics

The RGO Generation II reciprocating gait orthosis was jointly developed by Louisiana State University Medical Center and Durr-Fillauer Medical, Inc, to overcome four problems encountered with the existing model: 1) The high energy cost of locomotion; 2) the great arm strength required for patients to stand up from the seated position without assistance; 3) difficulty (especially for patients with hamstring contracture) in remaining standing owing to failure of the knee latch to lock except in full extension; and 4) problems in balancing when ambulating on an incline. The RGO Generation II employs concurrent electrostimulation of the rectus femoris and hamstrings to assist in rising and balancing and a ratchet-type latching device to improve safety and stability in standing. Alternating stimulation of the rectus femoris and contralateral hamstrings are used for locomotion. Testing in six patients with thoracic paraplegia demonstrated an average 30+% reduction in energy expenditure at a walking speed of .05 m/s and a 15+% reduction at .37 m/s; improved mobility and better balance on inclines; and unassisted rising in all patients. Walking range was increased from an average of 100 m to an average of 800 m. More research is needed to provide stair-climbing ability and to further reduce energy expenditure.

Biofeedback gait training system for temporal and distance factors

A biofeedback gait-training system has been developed which can deal with the gait problems of all subjects in any phase of rehabilitation: measurement, analysis, training and/or evaluation. The system is composed of a measuring walkway and a training walker. The walkway can measure all the temporal and distance factors of gait. The walker, with two parallel grasping bars and a CRT monitor, moves automatically with the aid of servo-motors. The system provides visual feedback for distance factors of gait and audio feedback for temporal factors. During the single-support phase the desired foot position for the next step and the supporting foot position are displayed on the CRT. The actual position of the foot placement is then overlaid for the double support duration that follows. A trainee learns to place the foot in such a way as to overlap the desired with the actual foot stamps on the CRT. The desired temporal factors are provided by buzzer tones. A trainee tries to shorten or elongate the duration of the respective phase of the gait cycle in accordance with the tone. Some experiments on normal subjects and on some with degenerative knee joints verified that the biofeedback signals were utilised effectively and that the walker was of value for improving pathological gait.