Changes in expression of the autophagy-related genes microtubule-associated protein 1 light chain 3β and autophagy related 7 in skeletal muscle of fattening Japanese Black cattle: a pilot study

Objective

Autophagy is a bulk degradation system for intracellular proteins which contributes to skeletal muscle homeostasis, according to previous studies in humans and rodents. However, there is a lack of information on the physiological role of autophagy in the skeletal muscle of meat animals. This study was planned as a pilot study to investigate changes in expression of two major autophagy-related genes, microtubule-associated protein 1 light chain 3β (MAP1LC3B) and autophagy related 7 (ATG7) in fattening beef cattle, and to compare them with skeletal muscle growth.

Methods

Six castrated Japanese Black cattle (initial body weight: 503±20 kg) were enrolled in this study and fattened for 7 months. Three skeletal muscles, M. longissimus, M. gluteus medius, and M. semimembranosus, were collected by needle biopsy three times during the observation period, and mRNA levels of MAP1LC3B and ATG7 were determined by quantitative reverse-transcription polymerase chain reaction. The expression levels of genes associated with the ubiquitin-proteasome system, another proteolytic mechanism, were also analyzed for comparison with autophagy-related genes. In addition, ultrasonic scanning was repeatedly performed to measure M. longissimus area as an index of muscle growth.

Results

Our results showed that both MAP1LC3B and ATG7 expression increased over the observation period in all three skeletal muscles. Interestingly, the increase in expression of these two genes in M. longissimus was highly correlated with ultrasonic M. longissimus area and body weight. On the other hand, the expression of genes associated with the ubiquitin-proteasome system was unchanged during the same period.

Conclusion

These findings suggest that autophagy plays an important role in the growth of skeletal muscle of fattening beef cattle and imply that autophagic activity affects meat productivity.

A 2,7-diamino-1,4,8-triazanaphthalene derivative selectively binds to cytosine bulge DNA only at a weakly acidic pH

The synthesis and properties of 2,7-diamino-1,4,8-triazanaphthalene (azaDANP) are described. AzaDANP is protonated only at a weakly acidic pH to bind to the cytosine bulge DNA duplex selectively. Upon binding of azaDANP to the cytosine bulge DNA, a new absorption band at 407 nm appears, and the absorption change of azaDANP on binding to the target is very sensitive to environmental pH with a bell-shaped pH-absorption profile.

Involvement of miRNAs in the early phase of halothane-induced liver injury

MicroRNAs (miRNA) form a class of small non-coding RNA molecules that negatively regulate gene expression. Most cellular pathways are modulated by miRNAs. However, the pathophysiological role of miRNAs during drug-induced liver injury (DILI) remains largely unknown. In this study, the possible involvement of miRNAs in DILI caused by the hepatotoxic drug halothane (HAL) was investigated. Toward this purpose, miRNA microarray studies of HAL-induced liver injury were performed in mice at five different time points up to 24h after dosing. To exclude any pharmacological effects on miRNA expression, isoflurane was used as a low hepatotoxic drug because it is structurally similar to HAL. Approximately 30-50% of the miRNA expression levels changed more than two-fold at every time point. In silico biological pathway analysis was performed to predict the targeted genes. Consequently, the miRNA gene down-regulation that occurred 1h after HAL administration was primarily related to inflammation, immune systems and liver injury. Based on additional in silico analyses, we identified miR-106b. Subsequently target of miR-106b was investigated using liver samples from mice with HAL-induced liver injury. Among the predicted targets, we discovered that a signal transducer and activator of transcription 3 (STAT3) was particularly up-regulated beginning during the early phase of HAL-induced liver injury. Collectively, the suppressed miR-106b expression, as well as the subsequent up-regulation of STAT3, was critical for the pathogenesis of HAL-induced liver injury.

Metabolic activation and inflammation reactions involved in carbamazepine-induced liver injury

Drug-induced liver injury is a major safety concern in drug development and clinical pharmacotherapy; however, advances in the understanding of the mechanisms of drug-induced liver injury are hampered by the lack of animal models. Carbamazepine (CBZ) is a widely used antiepileptic agent. Although the drug is generally well tolerated, only a small number of patients prescribed CBZ develop severe hepatitis. In the present study, we developed a mouse model of CBZ-induced liver injury and elucidated the mechanisms accounting for the hepatotoxicity of CBZ. Male BALB/c mice were orally administered CBZ for 5 days. The plasma levels of alanine aminotransferase and aspartate aminotransferase were prominently increased, and severe liver damage was observed via histological evaluation. The analysis of the plasma concentration of CBZ and its metabolites demonstrated that 3-hydroxy CBZ may be relevant in CBZ-induced liver injury. The hepatic glutathione levels were significantly decreased, and oxidative stress markers were significantly altered. Mechanistic investigations found that hepatic mRNA levels of toll-like receptor 4, receptor for advanced glycation end products, and their ligands were significantly increased. Moreover, the plasma concentrations of proinflammatory cytokines were also increased. Prostaglandin E(1) administration ameliorated the hepatic injury caused by CBZ. In conclusion, metabolic activation followed by the stimulation of immune responses was demonstrated to be involved in CBZ-induced liver injury in mice.

Involvement of immune-related factors in diclofenac-induced acute liver injury in mice

Drug-induced liver injury (DILI) is a major safety concern in drug development and clinical drug therapy. However, the underlying mechanism of DILI is little known. It is difficult to predict DILI in humans due to the lack of experimental animal models. Diclofenac, a non-steroidal anti-inflammatory drug rarely causes severe liver injury in human, but there is some evidence for immunoallergic idiosyncratic reactions. In this study, the mechanism of diclofenac-induced liver injury in mice was investigated. First, we established the dosing condition for liver injury in normal mice. Plasma ALT and AST levels were significantly increased in diclofenac-administered (80 mg/kg, i.p.) mice in a dose- and time-dependent manner. Among several interleukins (ILs) and chemokines, mRNA expression of helper T (Th) 17 cell-mediated factors, such as retinoid orphan receptor (ROR)-γt, and signal transducers and activators of transcription factor (STAT) 3 in the liver, and the plasma IL-17 level were significantly increased. Neutralization of IL-17 tended to suppress the hepatotoxicity of diclofenac, suggesting that IL-17 was partly involved. Gadolinium chloride (GdCl₃) administration demonstrated that Kupffer cells are not likely to be involved in diclofenac hepatotoxicity. Hepatic expressions of IL-1β mRNA and plasma IL-1β were significantly increased soon after the diclofenac administration. Then, the results of an in vivo neutralization study of IL-1β suggested that IL-1β was involved early in the time of pathogenesis of the diclofenac-induced liver injury. In conclusion, we firstly developed a diclofenac-induced acute liver injury model in normal mice, and the involvement of IL-17 and IL-1β was clarified.

Mechanism of exacerbative effect of progesterone on drug-induced liver injury

Drug-induced liver injury (DILI) is a major safety concern in drug development and clinical drug therapy. However, the underlying mechanism of DILI is little known. It is generally believed that women exhibit worse outcomes from DILI than men. Recently, we found that pretreatment of mice with estradiol attenuated halothane (HAL)-induced liver injury, whereas pretreatment with progesterone exacerbated it in female mice. To investigate the mechanism of sex difference of DILI, we focused on progesterone in this study. We found the exacerbating effect of progesterone in thioacetamide (TA), α-naphthylisothiocyanate, and dicloxacillin-induced liver injury only in female mice. Higher number of myeloperoxidase-positive mononuclear cells infiltrated into the liver and increased levels of Chemokine (C-X-C motif) ligand 1 and 2 (CXCL1 and CXCL2) and intercellular adhesion molecule-1 in the liver were observed. Interestingly, CXCL1 was slightly increased by progesterone pretreatment alone. Progesterone pretreatment increased the extracellular signal-regulated kinase (ERK) phosphorylation in HAL-induced liver injury. Pretreatment with U0126 (ERK inhibitor) significantly suppressed the exacerbating effect of progesterone and the expression of inflammatory mediators. In addition, pretreatment with gadolinium chloride (GdCl(3): inhibitor of Kupffer cells) significantly suppressed the exacerbating effect of progesterone pretreatment and the expression of inflammatory mediators. Moreover, posttreatment of RU486 (progesterone receptor antagonist) 1 h after the HAL or TA administration ameliorated the HAL- or TA-induced liver injury, respectively, in female mice. In conclusion, progesterone exacerbated the immune-mediated hepatotoxic responses in DILI via Kupffer cells and ERK pathway. The inhibition of progesterone receptor and decrease of the immune response may have important therapeutic implications in DILI.

Involvement of Th2 cytokines in the mouse model of flutamide-induced acute liver injury

Drug-induced liver injury is a growing concern for pharmaceutical companies and patients because numerous drugs have been linked to hepatotoxicity and it is the most common reason for a drug to be withdrawn. Flutamide rarely causes liver dysfunction in humans, and immune allergic reactions have been suggested in some cases. In this study, we investigated the mechanisms of flutamide-induced liver injury in BALB/c mice. Plasma alanine aminotransferase and aspartate aminotransferase levels were significantly increased 3, 6 and 9 h after flutamide (1500 mg kg⁻¹ , p.o.) administration. The biomarker for oxidative stress was not changed, but Th2-dominant immune-related factors, such as interleukin (IL)-4, IL-5, STAT6 and GATA-binding protein (GATA)-3, were induced in flutamide-administered mice. The pre-administration of monoclonal-IL-4 antibody suppressed the hepatotoxicity of flutamide. In addition, we investigated the effect of 13,14-dihydro-15-keto-PGD₂ (DK-PGD₂; 10 µg per mouse, i.p.) administration on flutamide-induced acute liver injury. Coadministration of DK-PGD₂ and flutamide resulted in a significant increase in alanine aminotransferase and a remarkable increase of macrophage inflammatory protein-2. In conclusion, we demonstrated that flutamide-induced acute liver injury is mediated by Th2-dominant immune responses in mice.

Alteration of gap junction proteins (connexins) following lateral fluid percussion injury in rats

Gap junctions are intercellular channels that mediate the cytoplasmic exchange of small hydrophilic molecules and are formed by a family of integral membrane proteins called connexins (Cxs). Cx43 is expressed predominantly in astrocytes, while Cx36 is expressed in neurons. In this study, we show alteration of Cx43 and Cx36 in the hippocampus after traumatic brain injury in rats. Adult male Sprague-Dawley rats were subjected to lateral fluid percussion injury of moderate severity. Brain coronal sections were used for immunohistochemistry with Cx43 and Cx36 antibodies. Cx43 immunoreactivity was increased in reactive astrocytes in the damaged hippocampus 24 hours after injury, and persisted for 72 hours. On the other hand, Cx36 immunoreactivity increased in CA3 neurons 1 hour after injury, and decreased later. These results indicate that gap junctions might participate in the pathophysiological process after traumatic brain injury.

Prediction of flood abnormalities for improved public safety using a modified adaptive neuro-fuzzy inference system

It is widely accepted that an efficient flood alarm system may significantly improve public safety and mitigate economical damages caused by inundations. In this paper, a modified adaptive neuro-fuzzy system is proposed to modify the traditional neuro-fuzzy model. This new method employs a rule-correction based algorithm to replace the error back propagation algorithm that is employed by the traditional neuro-fuzzy method in backward pass calculation. The final value obtained during the backward pass calculation using the rule-correction algorithm is then considered as a mapping function of the learning mechanism of the modified neuro-fuzzy system. Effectiveness of the proposed identification technique is demonstrated through a simulation study on the flood series of the Citarum River in Indonesia. The first four-year data (1987 to 1990) was used for model training/calibration, while the other remaining data (1991 to 2002) was used for testing the model. The number of antecedent flows that should be included in the input variables was determined by two statistical methods, i.e. autocorrelation and partial autocorrelation between the variables. Performance accuracy of the model was evaluated in terms of two statistical indices, i.e. mean average percentage error and root mean square error. The algorithm was developed in a decision support system environment in order to enable users to process the data. The decision support system is found to be useful due to its interactive nature, flexibility in approach, and evolving graphical features, and can be adopted for any similar situation to predict the streamflow. The main data processing includes gauging station selection, input generation, lead-time selection/generation, and length of prediction. This program enables users to process the flood data, to train/test the model using various input options, and to visualize results. The program code consists of a set of files, which can be modified as well to match other purposes. This program may also serve as a tool for real-time flood monitoring and process control. The results indicate that the modified neuro-fuzzy model applied to the flood prediction seems to have reached encouraging results for the river basin under examination. The comparison of the modified neuro-fuzzy predictions with the observed data was satisfactory, where the error resulted from the testing period was varied between 2.632% and 5.560%. Thus, this program may also serve as a tool for real-time flood monitoring and process control.

Predominant presence of Streptococcus anginosus in the saliva of alcoholics

Chronic alcohol consumption is known to be a major risk factor for cancers of the upper aerodigestive tract. The incidence of esophageal cancer (4.4%) in alcoholics is reported to be much higher than that in the Japanese population as a whole (0.0001%). This suggests the presence of specific factors in chronic alcohol consumption-related carcinogenesis. Recently, data showing a significant correlation between Streptococcus anginosus and carcinogenesis in the upper aerodigestive tract have been reported. In this study, the ratio of S. anginosus to oral bacteria in the saliva of 38 alcoholic patients was investigated to determine if there is an association between alcoholic patients and S. anginosus infection. The level of S. anginosus in the saliva from 22 healthy people, 41 esophageal cancer patients, 32 gastritis patients, and 24 periodontitis patients was also investigated and compared to the level in alcoholic patients. In the saliva from esophageal cancer patients, the level of S. anginosus was not significantly different from that of healthy people. The levels of S. anginosus in periodontitis and gastritis patients were also similar. In alcoholics, however, there was an extremely high level of S. anginosus, suggesting that they, rather than healthy people and general esophageal cancer patients, have a high risk for S. anginosus infection.

Heat stress-induced modulation of host defense against Toxoplasma gondii infection in mice

This study examined the effects of burn injury on murine immune response against Toxoplasma gondii infection. Male C57BL/6 mice were divided into 3 groups: T. gondii infection (group T), burn injury (group B), and burn injury followed by T. gondii infection (group BT). The survival of group BT was significantly lower than those of group B and group T. Parasite abundance in the tissues was determined by quantitative competitive-polymerase chain reaction. Group BT exhibited significantly higher numbers of T. gondii than group T. Antibody production against T.g.HSP30 in group BT was significantly lower than that in group T, whereas no significant difference was observed in SAG1-specific antibody production. Delayed-type hypersensitivity (DTH) specific for 2,4-dinitrofluorobenzene (DNFB) of both group B and group BT was significantly lower than that of group T. One week after infection, serum interferon-gamma (IFN-gamma) and interleukin (IL)-10 levels in group BT were significantly lower, whereas serum IL-6 levels were significantly higher than in group T Serum TNF-alpha levels in both group T and group BT were elevated at 1 wk after infection, although there was no significant difference between them. Serum IFN-gamma, IL-10, and TNF-alpha levels in group B were not elevated during the experimental term. In conclusion, the impaired antigen-specific antibody production and DTH response, together with the modulated patterns of cytokine responses, seemed to be strongly involved in the development of burn-induced immunosuppression and the consequent increased susceptibility to T. gondii infection in mice.

Molecular analysis of age-related changes of Streptococcus anginosus group and Streptococcus mitis in saliva

The purpose of this study was to survey the prevalence of streptococcal species, especially Streptococcus anginosus (which has been reported to be associated with cancer in the upper digestive tract), Streptococcus constellatus, and Streptococcus intermedius in the saliva of different age groups. A sequence analysis of 16S rDNA was performed and DNA quantified using real-time polymerase chain reaction. The S. anginosus level increased with age, whereas the levels of S. constellatus and S. intermedius did not change. Streptococcus mitis was the predominant species in the saliva of all the age groups but, unlike the S. anginosus, the proportion of S. mitis in the salivary bacteria decreased with age. The increase in S. anginosus with age should be carefully monitored because of its association with diseases, including cancer.

Vascular endothelial growth factor expression in pituitary adenomas

Vascular endothelial growth factor (VEGF) is known to be a mediator of angiogenesis and vascular permeability. A cystic component and hemorrhage are often found in pituitary adenomas. In the present study we assess the VEGF expression based on immunohistochemical examinations in 48 pituitary adenomas. All the adenomas showed some VEGF immunoreactivity mainly in the cytoplasm of tumor cells. Of the 48 adenoma-cases, 16 cases had a strong VEGF immunoreactivity, 26 cases had a moderate one, and 6 cases had a weak one. On the MR images, a cystic component was found in 16 cases (33.3%), and a hemorrhage was found in 18 cases (37.5%). The VEGF immunoreactivity had a significant relationship with the cystic component but neither the hemorrhage, size, recurrence, or HE classification. These findings suggest that VEGF might play a potential role in the pathogenesis of cystic formation in pituitary adenomas.

Characteristic phosphorylation of the extracellular signal-regulated kinase pathway after kainate-induced seizures in the rat hippocampus

Extracellular signal-regulated kinase (ERK) pathways play a crucial role in cell growth and long-lasting neuronal plasticity. Several studies have shown that phosphorylated-ERK (p-ERK) significantly increases after kainic acid (KA) administration. However, little or no information is available about the spatial distribution of p-ERK after KA-induced seizures. We herein show that KA-induced seizures significantly increase p-ERK in both neurons and astrocytes in rat brain using Western blots and immunohistochemistry. A strong immunoreactivity for p-ERK was induced in the dentate hilar neurons and CA3 neurons 30 mins and 6 hrs after KA injection. In addition, immunoreactivity for p-ERK was seen in astrocytes 6 hrs after KA injection. 72 hrs after KA injection, all pyramidal neurons had died. These findings suggest that the ERK pathway participates in the KA-induced neurotoxicity in the rat hippocampus.

Involvement of MyD88 in host defense and the down-regulation of anti-heat shock protein 70 autoantibody formation by MyD88 in Toxoplasma gondii-infected mice

This study investigated the influence of TLR (toll-like receptor)4, TLR2, and MyD88 in Toxoplasma gondii-infected wild-type (WT) mice and TLR4-, TLR2-, and MyD88-deficient mice. Ninety-five percent of MyD88-deficient mice died 10-16 days after intraperitoneal infection with 100 cysts of T. gondii Fukaya strain, whereas 95-100% of TLR4- and TLR2-deficient mice and WT C57BL/6 (B6) mice survived for more than 7 wk after T. gondii infection. The distribution of T. gondii in various organs of TLR4-, TLR2-, and MyD88-deficient mice and WT B6 mice was assessed 2 wk after T. gondii intraperitoneal infection using quantitative competitive polymerase chain reaction. In MyD88-deficient mice, high levels of T. gondii load were observed in the brain, tongue, heart, lungs, spleen, liver, mesenteric lymph node, and kidneys after infection. The T. gondii load was significantly increased in the lungs in both TLR4- and TLR2-deficient mice compared with WT B6 mice. High levels of anti-mouse heat shock protein (mHSP)70 autoantibody and anti-T. gondii HSP70 antibody production were detected in the sera from MyD88-deficient mice.

Content analysis of group work sessions in the context of an educational program for inpatient diabetes patients

This study investigated the changes in emotions and attitudes of diabetic patients as observed in group work sessions linked to an inpatient diabetic educational program. Using content analysis of transcripts from Sessions 1 and 3 of 8 selected groups (40 patients), in Session 1 negative emotions or attitudes such as anxiety, remorse, or self-blame, a lack of understanding of diabetes, along with a willingness to undertake self-care were frequently expressed. In Session 3, more positive emotions and attitudes towards self-care (willingness, specific plans, and resolutions), satisfaction, and relief or hope were frequently expressed. These results suggest that the patients participating in the group work sessions moved toward adaptation to diabetes, although the effects of the group work were not separated from those of the inpatient educational program.

Identification and characterization of a novel Golgi protein, GCP60, that interacts with the integral membrane protein giantin

We demonstrated previously that the integral membrane protein giantin has the Golgi localization signal at the COOH-terminal cytoplasmic domain (Misumi, Y., Sohda, M., Tashiro, A., Sato, H., and Ikehara, Y. (2001) J. Biol. Chem. 276, 6867-6873). In the present study, using this domain as bait in the yeast two-hybrid screening system, we identified a novel protein interacting with giantin. The 3.6-kilobase mRNA encoding a 528-amino acid protein of 60 kDa designated GCP60 was ubiquitously expressed and was especially abundant in the testis and ovary. Immunofluorescence and immunoelectron microscopy confirmed that GCP60 was co-localized with giantin in the Golgi complex. GCP60 was found to be a peripheral protein associated with the Golgi membrane, where a COOH-terminal domain of GCP60 interacts with the COOH-terminal cytoplasmic domain of giantin. Overexpression of the COOH-terminal domain of GCP60 caused disassembly of the Golgi structure and blocked protein transport from the endoplasmic reticulum to the Golgi. Taken together, these results suggest that GCP60 is involved in the maintenance of the Golgi structure by interacting with giantin, affecting protein transport between the endoplasmic reticulum and the Golgi.

[Dihydropyrimidine dehydrogenase activity in urothelial cancer--influence of UFT administration on DPD activity]

We measured the dihydropyrimidine dehydrogenase (DPD) activity considered to regulate the sensitivity of pyrimidine fluoride anti-cancer drugs in 50 cases of urothelial cancer (preoperative therapy group 10 cases, non-therapy group 40 cases). The association of DPD activity with pathological factors and TS activity as well as the influence of UFT oral administration on the DPD activity in tumors and blood were studied. The DPD activity in cancer tissue tended to be higher than that in the mucous membranes of the non-tumor region, but the difference was not significant. The DPD activity was high in infiltrative cancer (p < 0.05) but was not associated with atypia. The TS activity and DPD activity were manifested independently. The DPD activity in cancer tissue was significantly higher after UFT administration, with levels of 76.7 +/- 71.0 pmol/mg/min before administration and 220.6 +/- 129.1 pmol/mg/min after (p < 0.05). The DPD activity in peripheral blood was elevated after administration, but no significant difference was found. Since DPD activity is found in urothelial cancer tissue, 5-FU stable to DPD should preferably be used. It is also suggested that using a more potent DPD inhibitor in combination will produce higher anti-tumor effects.

Mn-SOD and Bcl-2 expression after repeated hyperbaric oxygenation

To clarify the mechanism of ischemic tolerance induced by HBO, we investigated the effect of HBO on immunoreactivity to Bcl-2 and Bax, apoptosis-regulating protein, or Mn-SOD, a radical scavenging system, in the CA1 sector of the gerbil hippocampus. Pretreatment comprising, five sessions at 2 ATA (atmosphere absolute) every other day, but not that comprising, ten sessions at 3 ATA every day, caused significant increases in Bcl-2 and Mn-SOD immunoreactivity in the CA1 sector compared with in the sham pretreatment group. No significant differences in Bax immunoreactivity and neuronal density in the CA1 hippocampal neurons was observed between the groups. These results suggest that protection against mitochondrial alterations after ischemia through Mn-SOD and/or Bcl-2 expression is related to the ischemic tolerance induced by repeated HBO pre-treatment.

[Laparoscopy-assisted total nephroureterectomy for renal pelvic and/or lower ureteral cancer]

PURPOSE

The usefulness of laparoscopy-assisted total nephroureterectomy for patients with renal pelvic and lower ureteral cancer is evaluated.

MATERIAL

Seven patients with renal pelvic cancer and four with lower ureteral cancer performed laparoscopy-assisted total nephroureterectomy from May 1997 to December 2000 (Ten males and one female, mean age 68.5 year-old).

METHOD

Of the 11 patients, the initial one received preoperative embolization of the renal artery. Under general anesthesia laparoscopy-assisted total nephroureterectomy underwent via transperitoneal approach in three patients and retroperitoneal approach in eight. After the kidney was completely dissected under laparoscopic procedure, it was delivered en bloc with ureter from the skin incision in the lower abdomen.

RESULT

Two patients needed conversion to open surgery. The mean operating time of nine patients except for conversion cases was 272 minutes and the mean blood loss was 313 ml. There was no major complication associated with laparoscopic procedure. There was no significant difference in both complication and recurrence rate between laparoscopy-assisted total nephroureterectomy and open surgery.

CONCLUSION

Laparoscopy-assisted total nephroureterectomy is an useful procedure for the treatment of patients with renal pelvic and lower ureteral cancer because it enables us to remove out the kidney and ureter from one small lower abdominal incision.

Isolation, structure determination, and synthesis of neodysiherbaine A, a new excitatory amino acid from a marine sponge

[structure: see text] A new excitatory amino acid, neodysiherbaine A (2), was isolated as a minor constituent of the aqueous extract from the marine sponge Dysidea herbacea. The structure was deduced by spectroscopic methods and established unambiguously by the total synthesis. The present synthesis, including as a key step cross-coupling of the 6/5-bicyclic core with an amino acid residue, is useful in constructing its structural analogues.

Induction of primary root curvature in radish seedlings in a static magnetic field

Primary roots of radish (Raphanus sativus L.) seedlings were exposed to an inhomogeneous static magnetic field generated by a permanent magnet, during continuous rotation on a 0.06 rpm clinostat, thereby reducing the unilateral influence of gravity. The roots responded tropically to the static magnetic field with the tropism appearing to be negative. These roots responded significantly (P < 0.05) to the south pole of the magnet. The significant tropic response was found for a magnetic flux density of 13-68 mT, for a field gradient of 1.8-14.7 T/m, and for the product of magnetic field and field gradient of 0.023-1.0 T(2)/m. A small, but insignificant, response of the roots to the north pole has also been found.

Organ infectivity of Toxoplasma gondii in interferon-gamma knockout mice

To determine the influence of interferon (IFN)-gamma on the organ infectivity and on the genetic susceptibility of susceptible (C57BL/6) and resistant (BALB/c) strains after peroral infection with cysts of Toxoplasma gondii. IFN-gamma knockout (KO) mice in C57BL/6 and BALB/c backgrounds were utilized. The kinetics of the changes in T. gondii abundance were evaluated with a quantitative competitive polymerase chain reaction assay in various organs at different times after peroral infection. In IFN-gamma KO mice, a T. gondii-specific gene, SAG1, was detected in all organs examined, and the protozoan proliferated much more actively than in wild-type mice. The abundance of T. gondii was much higher in mesenteric lymph nodes and the heart than in other organs. In contrast, in the nervous system organs and kidneys, only a weakly detectable reaction was observed. Toxoplasma gondii grew at a more rapid rate in the organs of IFN-gamma KO C57BL/6 mice than in the organs of IFN-gamma KO BALB/c mice during the course of infection. Destruction of the IFN-gamma gene showed remarkable effects on the infectivity in both susceptible and resistant mice.

Establishment of gene-vaccinated skin grafting against Toxoplasma gondii infection in mice

Vaccine effects of in vivo gene-vaccinated skin graft were evaluated against Toxoplasma gondii (T. gondii) infection. By using a gene gun, cDNA coding T. gondii SAG1 molecule was intracutaneously vaccinated into C57BL/6 (B6; a susceptible strain), BALB/c (a resistant strain) and (C57BL/6 x BALB/c) F1 (CBF1) mice, and the gene-vaccinated skin of these strains was transplanted to CBF1 mice. Regarding the antibody production against SAG1, CBF1-recipient mice transplanted with the SAG1 gene-vaccinated B6 skin were high responders, whereas CBF1 mice skin grafted with vaccinated skin of both BALB/c and CBF1 mice were low responders. The donor-derived LC/DC migrated to the draining lymph nodes of the recipients from the skin graft within 3 days. The vaccine effect against T. gondii challenge infection was obtained in CBF1 mice which received the skin graft of the SAG1 gene-vaccinated BALB/c mice.

Toxoplasma gondii Hsp70 as a danger signal in toxoplasma gondii-infected mice

Toxoplasma gondii Hsp70, T gondii Hsp30/bag1, and surface antigen 1 messenger RNAs were shown to be useful in analyzing stage conversion of T gondii between bradyzoites and tachyzoites. The high-level expression of T gondii Hsp70 was correlated with mortality in interferon-gamma knockout mice infected with T gondii. Tgondii Hsp70 inhibited the induction of nitric oxide release by peritoneal macrophages of T gondii-infected mice. These findings identify T gondii Hsp70 as a danger signal during lethal, acute T gondii infection.

Pituitary chromophobe carcinoma with a low level of serum gonadotropin and an aspermatogenesis in a dog

A 5-year-old male Shiba dog with progressive neurologic signs was examined by computed tomography (CT). A CT image of the brain disclosed a large, spherical high-density lesion in the thalamus and diencephalon. Serum LH, FSH and testosterone levels were all low. Macroscopically the large mass was connected with the sella turcia, and it was histopathologically diagnosed as a pituitary chromophobe carcinoma. An aspermatogenesis was observed in the testes. Therefore, it was suggested that the low levels of gonadotropin secretion from the pituitary gland due to the pituitary tumor resulted in the failure of maturation of spermatozoa and spermatids.

Serum midkine levels are increased in patients with various types of carcinomas

The level of expression of midkine (MK), a heparin-binding growth factor, is increased in many types of human carcinomas. An enzyme-linked immunoassay, which utilizes a combination of rabbit and chicken antibodies revealed that serum MK level in the controls (n = 135) was 0.154 +/- 0.076 (mean +/- SD) ng ml(-1)with an apparent cut-off value as 0.5 ng ml(-1). Serum MK level was significantly elevated in the cancer patients (n = 150) (P< 0.001); 87% of the patients showed levels of more than 0.5 ng ml(-1). All ten types of cancer examined showed a similar profile of serum MK level. There was no or weak correlation between C-reactive protein level, a marker of inflammation, and serum MK level. Furthermore, in case of gastric carcinoma and lung carcinoma, patients with stage I carcinoma already showed elevated serum MK levels. The present results indicated that serum MK could serve as a general tumour marker with a good potential for clinical application.

Anti-HSP70 autoantibody formation by B-1 cells in Toxoplasma gondii-infected mice

Formation of anti-Toxoplasma gondii HSP70 (TgHSP70) antibody cross-reactive to mouse HSP70 (mHSP70) was observed in the sera of BALB/c (a resistant strain) and C57BL/6 (B6; a susceptible strain) mice after peroral infection with T. gondii cysts of the Fukaya strain. The levels of anti-mHSP70 immunoglobulin G (IgG) autoantibody production in B6 mice were higher than those in BALB/c mice. The isotype and subclass of IgG of anti-TgHSP70 monoclonal antibodies cross-reactive to mHSP70 were mu and gamma3. Anti-mHSP70 autoantibody in T. gondii-infected BALB/c and B6 mice was shown to be produced by the CD5(+) subset of B cells (B-1a cells) but not by conventional B cells (B-2 cells). The epitopes recognized by anti-mHSP70 autoantibody were located primarily in the C-terminal fragment of mHSP70.

Establishment of a parabiotic rat model by anastomosis of common carotid artery

A cross circulation model was established by replacing mutual blood between two rats by anastomoses of each common carotid artery. In this model, parabiotic rats were shown to replace their mutual blood completely without any artificial materials or instruments, such as silicon tubes or pumps. The rate of blood exchange was measured by intravenous injection of Evans blue dye without the use of the radioactive materials that were so far commonly used. The partial alteration of blood circulation through microvascular surgery may reveal the mechanisms of organ tropism of bacteria, protozoa, and parasites. Microvascular surgery is available for reconstruction and analysis of organ functions as well as for clinical use in organplasty.

The prevalence of malnutrition and geo-helminth infections among primary schoolchildren in rural Kelantan

A cross-sectional study of the nutritional status of schoolchildren aged 7-10 years from the Kuala Betis Resettlement Scheme in Gua Musang, Kelantan was done. A total of 291 schoolchildren were examined but only 183 (62.9%) fecal samples were returned for geo-helminth infection analysis. The prevalence of stunting was 40.4% and underweight was 28.4%. A total of 127 schoolchildren (69.4%) were positive for at least one of the 3 geo-helminth infections. The most common geo-helminth was Ascaris lumbricoides (62.8%), followed by Trichuris trichiura (38.9%), and hookworm infection was relatively low (12.6%). All the anthropometric indices measured were lower in the geo-helminth infected children compared to the uninfected childen, except for the weight-for-height z-score. However the differences were insignificant Geo-helminth infections may not be a significant factor in malnutrition of these schoolchildren. However, with the availability of safe, efficacious and cheap broad spectrum anthelmintics, regular mass treatment should be given in selected areas where the prevalence of geo-helminth infections is still high, so that these schoolchildren will be able to achieve their growth potential during their school years.

A role of carboxy-terminal region of Toxoplasma gondii-heat shock protein 70 in enhancement of T. gondii infection in mice

We investigated the role of recombinant Toxoplasma gondii heat shock protein (rT.g.HSP) 70-full length, rT.g.HSP70-NH2-terminal region, or rT.g.HSP70-carboxy-terminal region in prophylactic immunity in C57BL/6 mice perorally infected with Fukaya cysts of T. gondii. At 3, 4, 5, and 6 weeks after infection, the number of T. gondii in the brain tissue of each mouse was measured by quantitative competitive-polymerase chain reaction (QC-PCR) targeting the surface antigen (SAG) 1 gene. Immunization with rT.g.HSP70-full length or r.T.g.HSP70-carboxy-terminal region increased the number of T. gondii in the brain tissue after T. gondii infection, whereas immunization with rT.g.HSP70-NH2-terminal region did not. These results suggest that T.g.HSP70-carboxy-terminal region as well as T.g.HSP70-full length may induce deleterious effects on the protective immunity of mice infected with a cyst-forming T. gondii strain, Fukaya.

Toxoplasmic encephalitis in patients with acquired immunodeficiency syndrome--four case reports

Four patients, all males aged 40-64 years, presented with toxoplasmic encephalitis associated with human immunodeficiency virus (HIV) infection manifesting as nonspecific neurological deficits such as epilepsy or hemiparesis. Magnetic resonance imaging showed single or multiple lesions with ring enhancement, mimicking metastatic brain tumor or brain abscess. Marked eosinophilia was noted in three patients. Two patients who received anti-toxoplasma chemotherapy in the early stage had a good outcome. However, the other two patients suffered rapid neurological deterioration and needed decompressive surgery, resulting in a poor outcome. Toxoplasma diffusely infects the whole central nervous system from the early stage. The outcome for patients who needed emergency surgery was poor. Therefore, this rare but increasingly common infectious disease must be considered in the differential diagnosis of a patient with neuroimaging findings similar to those of metastatic tumor or brain abscess. Appropriate chemotherapy should be started immediately after HIV-positive reaction is identified in patients with single or multiple mass lesions with ring enhancement.

Nucleoside diphosphate kinase required for coleoptile elongation in rice

Although several nucleoside diphosphate (NDP) kinase genes have been cloned in plants, little is known about the functional significance of this enzyme during plant growth and development. We introduced a chimeric gene encoding an antisense RNA of NDP kinase under the control of the Arabidopsis heat shock protein HSP81-1 promoter into rice (Oryza sativa L.) plants using the Agrobacterium tumefaciens transformation system. The expression of antisense RNA down-regulated the accumulation of mRNA, resulting in reduced enzyme activity even under the standard growth temperature (25 degrees C) in transgenic plants. Following heat shock treatment (37 degrees C), NDP kinase activities in some transgenic rice plants were more reduced than those grown under 25 degrees C. The comparison of the coleoptile growth under submersion showed that cell elongation process was inhibited in antisense NDP kinase transgenic plants, suggesting that an altered guanine nucleotide level may be responsible for the processes.

[Toxoplasma pericarditis without immunosuppressant disorder detected by polymerase chain reaction of pericardial fluid: a case report]

There have been several case reports, a total of 22 up to the present, of toxoplasma pericarditis. Out of them, in only a few cases the diagnosis was properly made with a proof of the microscopic presence of Toxoplasma gondii. This is the first report of toxoplasma pericarditis in which the presence of Toxoplasma gondii was detected by polymerase chain reaction of pericardial effusion. In addition, the previous reports will be reviewed, and compared to this present case. A 29-year-old woman, without immunosuppressant disorder, suffering from fever and orthopnea was admitted to our hospital. Blood chemistry findings indicated mild liver dysfunction and inflammation. Chest radiography showed cardiac enlargement. Electrocardiography showed sinus tachycardia and ST elevation. Echocardiography revealed a massive pericardial effusion. Pericardiocentesis demonstrated 638 ml of bloody fluid. Cytologic study of the fluid was class II for malignancy, and polymerase chain reaction to tuberculosis was negative. However, a high titer of the anti-toxoplasma antibody of 1: 20,480 (passive hemagglutination) indicated pericarditis caused by Toxoplasma gondii. Subsequently, Toxoplasma gondii was identified in the pericardial effusion by polymerase chain reaction. Clinical symptoms improved after pericardiocentesis, but 2 months later pericarditis recurred. Treatment was started with 800 mg acetylspiramycin daily but failed to improve the symptoms. Because of the development of pleuritis, treatment was changed to sulfadoxine 1,000 mg/pyrimethamine 50 mg. After the treatment with them, her symptoms improved. Only 22 cases of toxoplasma pericarditis have been reported worldwide and 15 of those cases were without immunosuppressant disorder. The usual symptoms at the onset of pericarditis without immunosuppressant disorder are fever, dyspnea and chest pain. Seven patients developed cardiac tamponade. Pericardiocentesis was performed in 8 cases and the pericardial fluid was hemorrhagic in 6. Pericardial thickening was detected in 5 cases. The diagnosis of toxoplasma infection is very difficult, because asymptomatic infection of Toxoplasma gondii is very common. Pericarditis is a disease difficult to confirm the etiology. Detection of Toxoplasma gondii in pericardial effusion by the polymerase chain reaction is very useful for its diagnosis.