Roles of primate spinal interneurons in preparation and execution of voluntary hand movement

To study the contribution of primate cervical interneurons (INs) to preparation and execution of normal voluntary hand movement we investigated their activity and correlational linkages to muscles in monkeys performing tracking tasks. During ramp-and-hold flexion-extension torques about the wrist most task-related spinal INs exhibited some activity during both flexion and extension, in unexpected contrast to the strictly unidirectional activity of corticomotoneuronal (CM) cells and motoneurons. Most INs increased their activity more in one of these two directions; response patterns in their preferred direction were typically tonic or phasic-tonic. Spike-triggered averages of EMG detected significant features in muscle activity for many task-related INs. Premotor INs (PreM-INs) were identified by post-spike facilitation or suppression with appropriate onset latencies after the trigger spike. Muscle fields of PreM-INs were smaller than those of supraspinal PreM cells in cortex and red nucleus, and rarely involved reciprocal effects on antagonist muscles. To investigate the relation of spinal INs to a repertoire of different muscle synergies, activity of INs was recorded from a macaque performing a multidirectional wrist task. The monkey generated isometric torques in flexion/extension, radial/ulnar deviation, pronation/supination, and executed a power grip that co-contracted wrist flexor and extensor muscles. Many INs showing task-modulated activity had preferred directions in this multidirectional space, typically with broadly tuned activation. The role of spinal INs in preparation for voluntary movement was revealed in monkeys performing instructed delay tasks. During the delay between a transient visual cue and a go signal a third of the tested INs showed significant delay modulation (SDM) of firing rate relative to the pre-cue rate. The SDM responses often differed from the INs' responses during the subsequent active torque period. In a monkey instructed by either visual or proprioceptive cues the delay period activity for many INs was similar in visual and perturbation trials, although other INs exhibited different SDM for visually and proprioceptively cued trials. These results suggest that spinal INs are involved, with cortex, in the earliest stages of movement preparation. The sensory input to INs could be identified in transient responses to the torque pulse, which showed two predominant patterns, consistent with inputs from cutaneous or proprioceptive receptors. We also investigated the task-dependent modulation of neural responses to peripheral input in a monkey performing wrist flexion/extension movements in a visually cued instructed delay task. Monosynaptic responses evoked by electrical stimulation of the superficial radial nerve through a cuff electrode were suppressed or abolished during the dynamic movement phase. Since task-related activity of the INs increased at the same time, the suppression was mediated by presynaptic rather than postsynaptic inhibition. These observations indicate that under normal behavioral conditions many spinal INs have response properties comparable to those previously documented for cortical neurons in behaving animals.

Huge cystic lymphangioma of the pancreas: report of a case

We report herein the case of a 33-year-old woman who presented with palpable abdominal swelling found to be caused by a huge lymphangioma of the pancreas. An abdominal computed tomographic (CT) scan showed a large multilocular cystic mass with water-dense contents, which was derived from the pancreatic head. A pancreaticoduodenectomy (PD) was performed because the tumor had invaded the duodenum. The resected tumor, which was 23 x 12 x 23 cm in size with 21 of serous fluid, was pathologically diagnosed as a cystic lymphangioma. The endothelial cells lining the internal surface of the cystic spaces were immunohistochemically positive for factor VIII-R antigen and CD31. Our review of the literature revealed 45 reports of lymphangioma of the pancreas, including this one, but to the best of our knowledge this is only the fifth case that required a PD. Nevertheless, we recommend that a complete resection be performed to reduce the risk of recurrence.

Accuracy of Digora system in detecting artificial peri-implant bone defects

This study was done to compare the diagnostic accuracy in detecting simulated intrabony defects around fixtures using Digora (DIG; Sordex Orion Corporation, Helsinki, Finland) compared with Ektaspeed Plus film (PLS; Eastman Kodak Co., Rochester, NY). Three titanium implant fixtures were placed in molar areas of three cadavers. Bone defects were created in the interproximal alveolar crest. Exposure time was adjusted to a PLS film and reduced to 1/5 only for DIG (1/5 DIG). The results of four observers were assessed. Sensitivity, specificity, accuracy, and under the receiver operator characteristic curve (ROC) area were evaluated. Statistical analyses were performed by using Friedman test and one-way ANOVA test. Mean sensitivity/specificity were 0.60/0.85 (DIG), 0.54/0.81 (1/5 DIG), and 0.64/0.58 (PLS). There were no statistically significant differences in the diagnostic accuracies. Digora had an equivalent performance to radiographic film in detecting intrabony defects adjacent to the implants, notwithstanding the amount of 1/5 of the exposure time.

High-rate methane fermentation of lipid-rich food wastes by a high-solids co-digestion process

This paper presents an experimental study on anaerobic degradation of lipids-rich food wastes by using the high solids co-digestion process. The experiments were conducted under mesophilic (35 degrees C) and thermophilic (55 degrees C) condition, respectively, by using a semi-continuous flow completely mixed reactor. The influent TS level was controlled at around 10%, while the hydraulic retention time (HRT) was changed from 15 days to 7.5 days. The lipids (fats or oil and grease) content in the influent TS was changed from 8% to 40% by adding salad oil (vegetable) and lard (animal) to the food wastes. The result of this study showed that the food wastes containing high lipids content was effectively degraded by the high solids co-digestion process and over 85% of lipid was degraded to biogas with 60-65% of methane. In addition, thermophilic methane fermentation was more effective for reducing lipids and had more higher loading capacity compared with mesophilic condition.

Immunocytochemical demonstration of the gap junction proteins connexin 43 and connexin 45 in the musculature of the rat small intestine

The immunohistochemical localization of connexin (Cx) 43 and Cx 45 in the musculature of the rat small intestine was studied at the ultrastructural level, with special reference to the interstitial cells of Cajal in the deep muscular plexus region (ICC-DMP). Cx 43 was localized at gap junctions formed between every group of cells, i.e., smooth muscle cell~smooth muscle cell, smooth muscle cell--ICC-DMP and ICC-DMP--ICC-DMP. In contrast, Cx 45 immunoreactivity was only detected at gap junctions between ICC-DMP--ICC-DMP. Since different types of Cx molecules have different properties for electrical and chemical coupling of cells, it is suggested that the homotypic network of ICC-DMP connected with Cx 45 gap junctions may function as an independent compartment segregated from the whole cellular network including the smooth muscle cells connected with Cx 43 gap junctions. It is further speculated that the ICC-DMP of the rat small intestine communicate with each other and with smooth muscle cells via the passage of messenger molecules through Cx 43, but they may use an additional mechanism, as yet unknown, for communications restricted to other ICC-DMP.

Electrocyclic rearrangement of pentamethylcyclooctapyrimidine-2,4-diones: reaction pathway into a 9,11-diazapentacyclo-[6.4.0.0(1,3).0(2,5).0(4,8)]dodecane system and a 9,11-diazapentacyclo [6.4.0.0(1,3).0(2,6).0(4,8)]dodecane system

Photolysis of 6-chloro-1,3-dimethyluracil and mesitylene in the presence of trifluoroacetic acid (TFA) at low temperature gave 1,3,5,7,9- and 1,3,6,8,10-pentamethylcyclooctapyrimidine-2,4-diones (1b, 1c). Sequential photoreaction of the former (1b) resulted in the formation of 9,11-diazapentacyclo[6.4.0.0(1,3).0(2,5).0(4,8)]dodecane-2,4-dione (2b) by way of 9-exo-methylene derivative (7b) and cyclobutaquinazoline (8b). On the other hand, UV-irradiation of 1c led to the bond shift isomer (5c) whose photolysis in the presence of TFA gave rise to the formation of the [6.4.0.0(1,3).0(2,6).0(4,8)]dodecane isomer (3c).

Inhibition of activated/memory (CD45RO(+)) T cells by oxidative stress associated with block of NF-kappaB activation

Impaired immune responses in cancer patients have been associated with oxidative stress. Increased levels of reactive oxygen species released from activated, tumor-infiltrating macrophages or granulocytes may therefore constitute a hurdle for effective immunotherapy against cancer. In this study, we investigated functional consequences and molecular events in T cells exposed to low levels of oxidative stress. We observed that cytokine production of human PBMC, upon stimulation with an HLA-A*0201-restricted influenza peptide and nonspecific receptor cross-linking, was reduced after exposure to micromolar levels of H2O2. Functional impairment as measured by IFN-gamma release occurred earlier and at lower doses of exogenously added H2O2 than required to induce apoptosis. This suggests that there is a dose window of oxidative stress leading to T cell unresponsiveness in the absence of apoptosis. The reduction of Th1 cytokines, induced by H2O2, was predominantly observed in memory/effector (CD45RO(+)) T cells and correlated with a block in NF-kappaB activation. IL-10 production was more profoundly influenced by low doses of H2O2 than IFN-gamma, TNF-alpha, and IL-2. The influence of H2O2 on production of IL-10 was not significantly different between memory/activated and naive T cells. These observations suggest that Th1 and Th2 cytokines are differently regulated under conditions of oxidative stress. Taken together, these findings may explain why Ag-experienced, CD45RO(+), T cells found in the tumor milieu are functionally suppressed.

Tumor necrosis factor-alpha induces coordinated changes in major histocompatibility class I presentation pathway, resulting in increased stability of class I complexes at the cell surface

It is demonstrated that similar to interferon gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha) induces coordinated changes at different steps of the major histocompatibility complex (MHC) class I processing and presentation pathway in nonprofessional antigen-presenting cells (APCs). TNF-alpha up-regulates the expression of 3 catalytic immunoproteasome subunits--LMP2, LMP7, and MECL-1--the immunomodulatory proteasome activator PA28 alpha, the TAP1/TAP2 heterodimer, and the total pool of MHC class I heavy chain. It was also found that in TNF-alpha--treated cells, MHC class I molecules reconstitute more rapidly and have an increased average half-life at the cell surface. Biochemical changes induced by TNF-alpha in the MHC class I pathway were translated into increased sensitivity of TNF-alpha--treated targets to lysis by CD8(+) cytotoxic T cells, demonstrating improved presentation of at least certain endogenously processed MHC class I--restricted peptide epitopes. Significantly, it was demonstrated that the effects of TNF-alpha observed in this experimental system were not mediated through the induction of IFN-gamma. It appears to be likely that TNF-alpha--mediated effects on MHC class I processing and presentation do not involve any intermediate messengers. Collectively, these data demonstrate the existence of yet another biologic activity exerted by TNF-alpha, namely its capacity to act as a coordinated multi-step modulator of the MHC class I pathway of antigen processing and presentation. These results suggest that TNF-alpha may be useful when a concerted up-regulation of the MHC class I presentation machinery is required but cannot be achieved by IFN-gamma. (Blood. 2001;98:1108-1115)

Genetic variability of respiratory syncytial virus subgroup a strain in 15 successive epidemics in one city

The genetic variability of 125 respiratory syncytial virus (RSV) subgroup A isolates over 15 successive epidemics from 1980 to 1995 in an urban population of Japan was determined. Allocation of isolates into lineages was archived by reverse transcriptase-polymerase chain reaction amplification of selected regions of the nucleoprotein (NP) and attachment (G) protein gene followed by restriction fragment length polymorphism (RFLP) analysis. Three and seven distinct restriction patterns of the NP and G gene were observed, respectively. When the NP and G gene RFLP analyses were combined, ten different genetic lineages were identified in the 125 isolates. The strains with the same genotype were isolated in each epidemic and the dominant lineages were replaced by others after every one to three consecutive epidemics. Nucleotide and amino acid sequencing of the variable region of G gene of these predominant isolates revealed differences of 5--28% between strains. There was, however, no apparent accumulation of diversity with age to indicate progressive changes. The dominant strains were often closely related to those isolated in other parts of the world at a similar time. These observations suggest that dominant RSV strains are replaced frequently by others that have been co-circulating or have recently entered the community from a worldwide reservoir. The change of dominant strains may be influenced by the buildup of immunological resistance in the community to successive epidemics of the same strain.

Purification and properties of two malate dehydrogenases from Candida sp. N-16 grown on methanol

Two malate dehydrogenases (MDH-M1 and MDH-M2) were found in a methanol-using yeast, Candida sp. N-16. MDH-M2 was induced with methanol. These enzymes were purified as electrophoretically and isoelectrophoretically homogeneous proteins. The molecular weights of MDH-M1 and MDH-M2 were estimated to be about 78,000 (homodimer) and 160,000 (homotetramer). Several kinetic properties were significantly different between the two enzymes. The value (2.07) of Vmax(oxaloacetate)/Vmax(malate) and Kcats (555 s(-1) for oxaloacetate, 481 s(-1) for NADH) of MDH-M2 were higher than the ratio (1.37) of Vmax and Kcats (241 s(-1) for oxaloacetate, 271 s(-1) for NADH) of MDH-M1, respectively. The activity of MDH-M2 was inhibited by a high concentration of NAD+ and the activity of MDH-M1 by oxaloacetate.

Diagnosis of pancreatic adenocarcinoma by detection of human telomerase reverse transcriptase messenger RNA in pancreatic juice with sample qualification

PURPOSE

We evaluated the diagnostic efficacy of detection of human telomerase reverse transcriptase (hTERT) message, a catalytic domain of human telomerase, in endoscopic retrograde pancreatography (ERP)-derived pancreatic juice.

EXPERIMENTAL DESIGN

Both hTERT and CD25 expression were detected by reverse transcription-PCR (RT-PCR) in 17 patients with pancreatic adenocarcinoma (PC), 12 patients with chronic pancreatitis (CP), and 7 patients with no ERP abnormality (N). In the same patients, beta-actin message was semiquantified by competitive RT-PCR. K-ras codon 12 mutations were concomitantly analyzed by enriched PCR-SSCP in 11 and 7 PC and CP cases, respectively.

RESULTS

Expression of hTERT was detected in 88% of PC cases and 17% of CP cases but not in the normal control (N). Alterations in K-ras were detected in 73% of PC cases and 57% of CP cases, respectively. beta-Actin mRNA was expressed in >3.0 x 10(1) copies/microl in all but two PC cases in which hTERT mRNA was not detected. CD25-positive and -negative peripheral lymphocytes were isolated from a normal volunteer using a fluorescent activating cell sorter. The hTERT message was detected in CD25-positive peripheral lymphocytes and in 18, 25, and 0% of the pancreatic juice samples from PC, CP, and N cases, respectively. All CP cases expressing hTERT message were also CD25 positive.

CONCLUSIONS

These results suggest that detection of hTERT mRNA in pancreatic juice is a powerful tool to discriminate PC from CP, particularly when the samples are qualified against beta-actin mRNA levels and contaminating CD25-positive lymphocytes.

Apoptosis observed in murine peritoneal macrophages treated with interferon gamma through staphylococcal enterotoxin-dependent cell-mediated cytotoxicity

The concept of superantigens is well-known and widely accepted. In this brief communication, we analyze the behaviour of antigen-presenting cells after T-cell activation by staphylococcal enterotoxin B, a representative superantigen. We tried to activate murine T cells by inflammatory mouse peritoneal macrophage in the presence of staphylococcal enterotoxin B, but no T-cell activation was observed. We, therefore, analyzed surface-specific antigens of the macrophages. They expressed insufficient amounts of MHC class II, CD80 and CD86 molecules on the surface of the cells. On the contrary, increased amounts of MHC class II and CD86 molecules on the cell surfaces were observed after incubation with interferon gamma. Interferon gamma-primed macrophages were found to be competent to activate T cells in the presence of staphylococcal enterotoxin B. To our surprise, these macrophages underwent apoptosis in parallel with T-cell activation.

Sequence dependence of post-tetanic potentiation after sequential heterosynaptic stimulation in the rat auditory cortex

1. To investigate the mechanisms for the coding stimulus sequence in the auditory cortex (AC), post-tetanic potentiation (PTP) was recorded after sequentially combined heterosynaptic stimulation was applied in rat AC slices. 2. Brief tetanic stimulation (TS) was applied at two sites on AC slices at intervals of 0.5-10 s. PTP of field potentials was induced by the earlier TS, rather than the later TS. PTP was followed by sequence-dependent long-term potentiation (LTP). 3. Using Ca(2+) imaging in the slices loaded with rhod-2, a Ca(2+) indicator, a sequence-dependent distribution of PTP was found in AC slices. 4. The sequence-dependent PTP in excitatory postsynaptic potentials (EPSPs) was observed in supragranular pyramidal neurons. 5. The sequence dependence of PTP was not significantly affected by 1 microM bicuculline, an antagonist of GABA(A) receptors, or 100 microM 2-hydroxysaclofen, an antagonist of GABA(B) receptors. 6. Depolarization and firing recorded in pyramidal neurons during the later TS were less vigorous than when the slices were incubated in the control medium. However, this suppression of the responses during the later TS was not observed in the presence of 50 microM atropine, an antagonist of muscarinic receptors. 7. PTP was induced by the earlier and later TS in the presence of 50 microM atropine, so that the sequence dependence of PTP was abolished. Pirenzepine (50 microM), an antagonist of muscarinic M1 receptors, but not methoctramine (30 microM), an antagonist of M2 receptors, eliminated the sequence dependence of PTP. 8. These findings suggest that the sequence dependence of PTP in AC might have a role in the temporal processing of auditory information on the scale of seconds.

Subsequent pregnancy outcome in patients with spontaneous resolution of HCG after evacuation of hydatidiform mole: comparison between complete and partial mole

This study compared subsequent pregnancy outcome in patients with complete and partial hydatidiform moles. Among 1052 patients with molar pregnancy (complete mole, 801; partial mole, 251) monitored at Chiba University Hospital between 1981 and 1999, 891 patients (84.7%) had spontaneous resolution of human chorionic gonadotrophin (HCG) after mole evacuation, and 161 patients (15.3%) required chemotherapy. Of the 891 patients, 438 (49.2%) had 650 subsequent pregnancies. The pregnancy outcome was not significantly different in patients with complete and partial moles, and was comparable with that in the general Japanese population. The incidence of repeat molar pregnancy in patients with complete and partial mole (1.3 and 1.5% respectively) was 5-fold higher than that of the general population, while no increased risk of persistent gestational trophoblastic tumour (GTT) associated with later molar pregnancy was observed. During HCG follow-up, 10 patients (1.1%) developed secondary high-risk GTT between 14 and 54 months after mole evacuation. The incidence of high-risk GTT in patients with and without subsequent pregnancies was 0.46% (2/438) and 1.8% (8/453) respectively (P = 0.1243). In conclusion, patients with complete and partial mole can anticipate a normal future reproductive outcome, and pregnancies after experiencing hydatidiform mole may not affect the development of high-risk GTT.

Genetic variability of respiratory syncytial virus subgroup B strain isolated during the last 20 years from the same region in Japan: existence of time-dependent linear genetic drifts

The genetic variability of 32 respiratory syncytial virus (RSV) sub-group B isolates from a single community in Japan during the 20 years from 1980 to 1999 was determined. Two variable regions of the attachment (G) protein gene were amplified by reverse transcriptase-polymerase chain reaction amplification and their products were sequenced directly. Phylogenetic analysis of nucleotide sequences revealed seven distinct branches in which strains isolated during seasons of close proximity were located: however, isolates from the same season were often in plural branches. There was a tendency for recent isolates to lie at the end of each branch and these linear evolutionary changes were typically represented in a branch containing nine strains isolated during 6 seasons from '80 to '86. Three kinds of usages of stop codons were confirmed and isolates located in each branch used the same stop codons. These observations suggest that there are multiple subgroup B lineages co-circulating and that each lineage strain may exhibit linear evolutionary genetic drifts in order to survive over successive epidemics within the same population, although it has a conserved uniform G protein length with the use of the same stop codon.

Significance of perivascular lymphocytic infiltrates in endometrial carcinoma

BACKGROUND

The objective of this study was to clarify the significance of perivascular lymphocytic infiltrates (PLI) in endometrial carcinoma.

METHODS

The pathologic records of 127 patients with endometrioid type adenocarcinoma confined to the uterus were reviewed retrospectively. The patients were divided into 4 groups based on the presence or absence of vascular invasion (VI) and PLI: VI-PLI- (n = 87), VI-PLI+ (n = 7), VI+PLI+ (n = 22), and VI+PLI- (n = 11). Pathologic features including tumor grade, myometrial invasion, cervical involvement, vascular invasion-associated changes (VIAC; VI and/or PLI), tumor size, ovarian metastasis, and pelvic lymph node metastasis were assessed statistically.

RESULTS

Selective pelvic lymphadenectomy was performed in 108 patients, and metastasis was identified in 6 cases (5.6%). Lymph node metastasis was the only independent variable related to recurrence (Cox regression analysis, P = 0.0008). Perivascular lymphocytic infiltrates correlated closely with VI (Fisher exact test, P < 0.0001). Vascular invasion-associated changes was the best predictor of lymph node metastasis (logistic regression analysis, P = 0.039), but among the three categories of VIAC, only the VI+PLI- group was significantly associated with lymph node metastasis (P = 0.0045). The odds ratios of VI+PLI- and VI+PLI+ cases for lymph node metastasis were 64.54 and 3.24, respectively.

CONCLUSIONS

Although VIAC is the best predictor of lymph node metastasis, the presence of PLI is associated with a lower risk of lymph node metastasis among VIAC groups.

[Cavernous sinus dural arteriovenous shunt presenting with subarachnoid hemorrhage and acute subdural hematoma: a case report]

Cavernous sinus dural arteriovenous shunt (CdAVS) usually presents with exophthalmos, conjunctival chemosis, ophthalmoplegia, headache, bruit, or pulsatile tinnitus. Intracranial hemorrhage associated with CdAVS is rare. We describe a patient with CdAVS presenting with subarachnoid hemorrhage and acute subdural hematoma. A 65-year-old woman presented headache and temporary loss of consciousness and was transferred to our hospital. On admission, the patient was alert and complained of a left-sided temporal headache. There were no ocular symptoms. A CT scan revealed subarachnoid hemorrhage and left acute subdural hematoma. When we prepared for cerebral angiography, the patient presented loss of consciousness following sudden onset of severe headache. Urgent angiography revealed left CdAVS, which was fed by both the internal carotid artery and the external carotid artery and drained only into ipsilateral (left) vein of the sylvian fissure. Aneurysmal dilatation of the draining veins and leptomeningeal drainage were present. No cerebral aneurysms were detected. After the angiography, a CT scan showed enlarged subdural hematoma, so left fronto-temporo-parietal craniotomy was immediately performed. On opening the dura mater, arterial bleeding from Sylvian fissure appeared and was uncontrollable. Unfortunately, the patient died 3 days after the operation. We concluded that subarachnoid hemorrhage and subdural hematoma were due to the rupture of engorged cortical veins. Our case report suggests that CdAVS with angiographic findings such as aneurysmal dilatation of the draining veins and leptomeningeal drainage should be treated urgently because of the high risk of the life-threatening complications resulting from a surgically uncontrollable hemorrhage.