Sea turtles compensate deflection of heading at the sea surface during directional travel.

Air-breathing marine animals, including sea turtles, utilise two fundamentally different environments (i.e. sea surface and underwater) during migration. Many satellite telemetry studies have shown travel paths at relatively large spatio-temporal scales, discussing the orientation and navigation mechanisms that guide turtles. However, as travel paths obtained by satellite telemetry only reflect movements at the surface, little is known about movements and orientation ability underwater. In this study, to assess orientation ability both at the surface and underwater, fine-scale 3-D movements of free-ranging loggerhead turtles Caretta caretta were reconstructed by using multi-sensor data loggers. Video systems ('Crittercam') were also used to record the behaviour of the turtles and the visual information surrounding the turtles. During August and October in 2006 and 2007, eight turtles were released from Otsuchi Bay, Japan (39 degrees 20'30N, 141 degrees 56'00E), and a total of 118 h of 3-D movements were reconstructed. Turtles maintained highly straight-line courses (straightness index >0.95) during 41% of the total duration (i.e. 'travelling periods'). During travelling periods, turtles swam continuously, maintaining unidirectional heading throughout dives whereas turtles changed heading remarkably at the surface. Despite highly directional movements during dives, travel direction tended to shift by the end of dives lasting 10 minutes or more. Such deflections seemed to be compensated during subsequent surfacing periods because there was a negative relationship between changes in travel direction arising during dives and subsequent surfacing periods. Therefore, remarkable changes in heading at the surface could be interpreted as direction-searching behaviour. Our results suggested that turtles undertaking directional travel were more dependent on directional information that was reliable at the surface.

Synaptic modulation of excitatory synaptic transmission by nicotinic acetylcholine receptors in spinal ventral horn neurons.

Nicotinic acetylcholine receptors (nAChRs) are distributed widely in the central nervous system and play important roles in higher brain functions, including learning, memory, and recognition. However, functions of the cholinergic system in spinal motoneurons remain poorly understood. In this study, we investigated the actions of presynaptic and postsynaptic nAChRs in spinal ventral horn neurons by performing whole-cell patch-clamp recordings on lumbar slices from male rats. The application of nicotine or acetylcholine generated slow inward currents and increased the frequency and amplitude of spontaneous excitatory postsynaptic currents (sEPSCs). Slow inward currents by acetylcholine or nicotine were not inhibited by tetrodotoxin (TTX) or glutamate receptor antagonists. In the presence of TTX, the frequency and amplitude of miniature excitatory postsynaptic currents (mEPSCs) were also increased by acetylcholine or nicotine. A selective α4ß2 nicotinic receptor antagonist, dihydro-ß-erythroidine hydrobromide (DhßE), significantly decreased nicotine-induced inward currents without affecting the enhancement of sEPSCs and mEPSCs. In addition, a selective α7 nicotinic receptor antagonist, methyllycaconitine, did not affect either nicotine-induced inward currents or the enhancement of sEPSCs and mEPSCs. These results suggest that α4ß2 AChRs are localized at postsynaptic sites in the spinal ventral horn, non-α4ß2 and non-α7 nAChRs are located presynaptically, and nAChRs enhance excitatory synaptic transmission in the spinal ventral horn.

Tissue angiotensinogen gene expression induced by lipopolysaccharide in hypertensive rats.

There is now convincing evidence that various tissues express their own tissue renin-angiotensin system, which may be regulated independently of the systemic renin-angiotensin system. However, little information is available on the regulation of the tissue renin-angiotensin system. We investigated the regulation of tissue angiotensinogen gene expression with respect to the development of hypertension. We measured basal and lipopolysaccharide-stimulated plasma angiotensinogen concentrations by radioimmunoassay and examined the expression of tissue angiotensinogen by Northern blot analysis in spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) at 4 and 13 weeks of age. Basal plasma angiotensinogen concentration in SHR was comparable to that in WKY at 4 weeks of age and was significantly higher than that in WKY at 13 weeks of age. Lipopolysaccharide induced a significant increase in plasma angiotensinogen concentration in both WKY and SHR at 4 and 13 weeks of age. At 4 weeks of age, the basal levels of angiotensinogen mRNA in the liver, fat, adrenal, and aorta were higher in WKY than in SHR. At 13 weeks of age, the basal levels of angiotensinogen mRNA in the fat, adrenal, aorta, spleen, and kidney were higher in WKY than in SHR, while that in the liver did not differ significantly between the two strains. At 4 weeks of age, pretreatment with lipopolysaccharide increased the angiotensinogen mRNA levels in the liver, fat, adrenal, and aorta in both WKY and SHR. At 13 weeks of age, pretreatment with lipopolysaccharide increased the angiotensinogen mRNA levels in the liver, aorta, and adrenal; decreased those in the spleen; and had no effect in the kidney in both WKY and SHR. Interestingly, lipopolysaccharide increased the angiotensinogen mRNA level in fat only in SHR, with no effect in WKY, at 13 weeks of age. Lipopolysaccharide stimulated tumor necrosis factor-a mRNA expression in fat of WKY and SHR, and the increase in tumor necrosis factor-alpha mRNA level in SHR was significantly greater than that in WKY. Therefore, the increased tumor necrosis factor-alpha mRNA expression may be involved in the increased lipopolysaccharide-induced expression of angiotensinogen gene in fat of SHR at 13 weeks of age. These data suggest that the transcriptional and probably posttranscriptional regulation of angiotensinogen mRNA differs between SHR and WKY, that the regulation of angiotensinogen gene expression is tissue-specific, and that the altered expression of the angiotensinogen gene may be involved in the development of hypertension.

A rapid anticancer drug screening assay by [14C] thymidine uptake in cultured human cancer cells.

A rapid screening test by suppression of DNA synthesis in cancer cells was developed with [methyl-14C]-thymidine (14C-TdR), a microculture filtration plate and a radiochromatoscanner. Mitomycin, tamoxifen and 5-fluorouracil (5-FU) were tested against four human gastric cancer cell lines and HeLa cells. The tetrazolium-based colorimetric (MTT) assay underestimated cell inactivation by mitomycin in three cell lines compared with the cell count and the 14C-TdR assays. Inactivation by 5-FU in one cell line by 14C-TdR uptake was considerably lower than that by other methods. Thus neither the radio-labelled DNA precursor uptake nor the MTT assay is suitable for every anticancer drug but they are complementary.

Developmental localization of semaphorin H messenger RNA acting as a collapsing factor on sensory axons in the mouse brain.

Semaphorins/collapsins, a family of genes with a semaphorin domain conserved from insects through to mammals, are believed to be involved in axon guidance during neuronal development. We report the expression patterns of mouse semaphorin messenger RNAs. Among secreted semaphorins, mouse semaphorin H is structurally most similar to semaphorin III/D, the first semaphorin identified as a collapsing factor for sensory axons. However, its expression patterns apparently differ from those of semaphorin III/D. The messenger RNAs are distributed in the brain widely but unevenly during development, in particular, in the main olfactory bulb, hippocampus and pontine nucleus. In the trunk, the expression level is high in mesodermal tissues surrounding the dorsal root ganglia, while it is low in the spinal cord. Moreover, we examined whether this molecule has activity to collapse growth cones of sensory neurons, as well as semaphorin III/D. Mouse semaphorin H collapsed growth cones of sensory neurons of the dorsal root ganglion in a dose-dependent manner, and anti-neuropilin antibodies inhibited this activity. Taken together, these results suggest that mouse semaphorin H can function as a chemorepellent to guide sensory peripheral nerves, most likely via neuropilin as a receptor.

A possible role of airway epithelium in modulating hyperresponsiveness.

1. In order to examine the role of airway epithelium in the responsiveness of smooth muscle in man, we measured the contractile responses to acetylcholine (ACh), histamine, and prostaglandin F2 alpha (PGF2 alpha) and the relaxation response to isoprenaline (Isop), in 48 bronchi obtained from 10 patients who received surgery. Responses were measured in the presence and absence of the epithelium. 2. Removal of epithelium (by rubbing the mucosa gently with forceps) significantly increased the contractile responses evoked by ACh, histamine and PGF2 alpha. 3. In contrast, removal of epithelium did not alter the relaxation response to Isop. 4. To clarify the mechanism underlying this epithelial inhibitory effect on smooth muscle contraction, we measured the contractile responses of dog trachea with the epithelium removed to increasing concentrations of ACh. After measuring the control response, we added about 0.1 g of the chopped epithelium in the organ chamber, and measured the response again. 5. After adding airway epithelium and incubating with tracheal strips, the contractile response of tracheal strips decreased significantly as compared to the control response. 6. These results show that airway epithelium possesses the ability to decrease the smooth muscle contraction to ACh, histamine and PGF2 alpha in man and dogs. 7. The mechanism of this inhibitory effect of the airway epithelium is not explained by a change in mechanical property of the airway nor the change in diffusion of these drugs to the smooth muscle across the epithelium. Thus, these results suggest that airway epithelium may have an important role in modulating smooth muscle tone, possibly by inactivation of these mediators, or by releasing an epithelium-derived relaxing factor.

Cell killing induced by decay of 125I during the cell cycle: comparison of 125I-antipyrine with 125I-bovine serum albumin.

The lethal effects induced by the decay of 125I in synchronized L5178Y cells were studied by suicide experiments. We used 125I-antipyrine, which is freely diffusible in cells, and 125I-bovine serum albumin (BSA), which remains outside the cells. Synchronized cells mixed with either 125I-antipyrine or 125I-BSA were frozen and stored at -196 degrees C for various periods to accumulate 125I decays. A clonogenic assay was used to measure the killing of these stored cells. Cells in G1-S and G2-M phases were more sensitive than those in late S phase for both 125I treatments. The ratio of survival in late S to that in G1-S (late S/G1-S) obtained by the decay of 125I-antipyrine, however, was much smaller than that obtained by the decay of 125I-BSA in the dose range examined. These results suggest that Auger electrons emitted from 125I-antipyrine cause a high-LET-type effect. The reason for the high-LET effect must be the intracellular localization of 125I-antipyrine and its closer contact with DNA.

Mouse semaphorin H inhibits neurite outgrowth from sensory neurons.

Mouse semaphorin H (M-semaH) was structurally similar to semaphorin III/D, a mammalian homologue of collapsin 1 which was identified as a collapsing factor for sensory nerves. In this study we investigated the expression patterns of M-semaH mRNA and the protein binding sites in the trunk of mouse embryos. M-semaH mRNA was expressed in the mesenchymal tissues surrounding each dorsal root ganglia. These tissues include the caudal sclerotome and perinotochordal mesenchyme, which were thought to express factors repulsive to axons. M-semaH binding was detected on the spinal nerves. We further investigated, using in vitro co-culture assay, whether M-semaH acted as a chemorepulsive molecule on sensory axons. The results suggested that M-semaH was a candidate for a chemorepellent expressed in the mesenchyme surrounding the sensory ganglia, which is involved in the axonal guidance mechanism of sensory nerves in the trunk.

Enterotoxin production by Staphylococcus aureus clones and detection of Brazilian epidemic MRSA clone (III::B:A) among isolates from food handlers.

Staphylococcus aureus is a major bacterial pathogen involved in a wide range of diseases varying from infections to toxaemia. Staphylococcal food-poisoning syndrome is caused by ingestion of bacterial enterotoxins. These toxins are microbial superantigens and may also be virulence factors involved in staphylococcal infection. This study determined the enterotoxin types and pulsed-field gel patterns found among S. aureus isolates obtained from food handlers in community or hospital-located kitchens. Staphylococcal enterotoxin C was the most frequent enterotoxin produced. The data also suggested horizontal spread of ent genes among isolates belonging to the Brazilian epidemic MRSA clone III::B:A. A subclone of MRSA clone III::B:A was isolated from two hospital kitchen workers. This was the first report of this clone from a hospital in Teresina, Piaui State, although the presence of this MRSA clone has already been reported in six other Brazilian cities.

The mechanism of Bodian's silver staining: effect of copper ion on silver impregnation.

We studied the effect of the duration (0.5-48 h) of silver impregnation on the intensity of Bodian's silver staining using formalin-fixed, paraffin-embedded sections of a human brain. The silver ion (Ag+) and copper ion (Cu2+) in the silver protein solution were quantified simultaneously for treatments of various durations. Both the intensity of staining and the quantities of Ag+ and Cu2+ were greatly affected by the duration of silver impregnation. While the quantity of Ag+ considerably decreased during the first 4 h of impregnation, that of Cu2+ greatly increased. Only small changes were observed in both ions after 12 h. Neurofibrils or axons, and neurofibrillary tangles (NFTs) were clearly stained after 12-24 and 16-48 h of impregnation, respectively. Strong staining of these components was not observed for other durations of treatment. The amount of metallic copper in silver impregnation also affected both the intensity of staining and the quantities of Ag+ and Cu2+ in the silver protein solution. Ag+ and Cu2+ were also present in the gold trichloride acid solution in which the section was toned. These findings suggest that both Cu2+ derived from metallic copper and silver protein are deposited on sections during silver impregnation, that the amount of Cu2+ may determine the amount of silver protein deposited on the section, and that the reduced (metallic) form of silver and copper on the section may participate in gold toning. Thus, to achieve strong staining of a desired component, it is important to examine the conditions of silver impregnation (i.e. duration and amount of metallic copper). For strong staining of neurofibrils, axons and NFTs, optimal results are obtained by the addition of 5 g of metallic copper foil to 100 ml of 1% silver protein solution, and by 16-24 h of impregnation.

Nonspecific granulomatous prostatitis.

Nonspecific granulomatous prostatitis is a relatively rare disorder of the prostate. We encountered 4 cases of this type of chronic inflammation, including 1 case of xanthogranulomatous prostatitis. In all cases the diagnosis was made by histologic examination of specimens obtained by transurethral resection, retropubic prostatectomy, or transrectal needle biopsy. Echography revealed a hypoechoic lesion in the case of xanthogranulomatous prostatitis, while the other cases showed no specific findings except for the associated adenomas. The major symptoms were frequency and dysuria caused by urinary tract infection or benign prostatic hyperplasia associated with the granulomatous prostatitis.

Phase II trial of combination chemotherapy with cisplatin, carboplatin and etoposide in stage IIIB and IV small-cell lung cancer. Fukuoka Lung Cancer Study Group.

PURPOSE: A phase II trial combining cisplatin, carboplatin and etoposide was conducted in previously untreated patients with stage IIIB and IV small-cell lung cancer, in an attempt to increase response rates and prolong survival. METHODS: Previously untreated patients with small-cell lung cancer, with measurable disease, aged < or = 72 years, performance status < or = 2, and adequate hematologic, hepatic and renal function were enrolled in the study. They were treated with 80 mg/m2 cisplatin on day 1, 100 mg/m2 carboplatin on days 2, 3 and 8, and 50 mg/m2 etoposide on days 1, 2, 3 and 8. RESULTS: A total of 46 patients (20 with stage IIIB and 26 with stage IV disease) were enrolled in the study. A total of 186 courses of chemotherapy were given, and the dose was reduced in 27 courses (15%). The chemotherapy was repeated for four or more courses in 30 patients. There were 10 complete responses and 32 partial responses, for a total response rate of 91% (95% confidence interval, 79% to 98%). The median survival time and 2-year survival rates were 18 months and 22% for stage IIIB disease, and 14 months and 15% for stage IV disease. Major side effects were hematologic: leukopenia, anemia, and thrombocytopenia of grade 3 or more occurred in 48%, 46%, and 43% of patients, respectively. CONCLUSIONS: The three-drug regimen of cisplatin, carboplatin and etoposide is feasible and active against small-cell lung cancer.

Alzheimer amyloid beta/A4 peptide binding sites and a possible 'APP-secretase' activity associated with rat brain cortical membranes.

We carried out ligand binding experiments on membranes from rat brain cortical grey matter using radioiodinated beta/A4 8-17, with non-specific binding determined by the addition of 10 microM unlabelled peptide. Specific, reversible binding amounted to 60-75% of total binding and showed a clear dependence on time, temperature, pH and membrane concentration. Kinetic analyses indicated a high-affinity binding site with an apparent KD of 440 pM. However, the ligand was partly degraded with loss of the Ser8, Lys16 and Leu17 residues. Excision of the two C-terminal amino acids was inhibited by EDTA, EGTA, dithiothreitol or Zn2+ but was stimulated by Ca2+ or Mn2+. These studies demonstrate high-affinity binding sites for beta/A4 8-17 (or its derivatives) in rat brain, suggesting that this region may contain a physiologically important amino acid sequence and identify a potential membrane-associated amyloid precursor protein (APP) secretase activity.

Localization of serotonin-immunoreactivity in the central nervous system of Octopus vulgaris by immunohistochemistry.

5-Hydroxytryptamine (5-HT, serotonin)-containing cells were localized in the central nervous system of Octopus vulgaris by use of the unlabelled peroxidase-antiperoxidase complex (PAP) immunohistochemical method employing highly specific antibodies to 5-HT present in paraformaldehyde-fixed tissue. Antibodies were raised in rabbits against an immunogen prepared by coupling 5-HT to bovine thyroglobulin (BTG) or to bovine serum albumin (BSA) with formaldehyde as the coupling reagent. The specificity of the immune reaction was studied by both absorption test and radioimmunoassay. The distribution of 5-HT immunoreactivity observed in octopus brain was essentially similar to that reported by other workers who used formaldehyde- or glyoxylic acid-induced fluorescence method. In addition, this immunohistochemical technique revealed 5-HT-containing perikarya in both the chromatophore and the palliovisceral lobes which were not detected by the previous fluorescence histochemical method. Thus, this immunocytochemical procedure appears to be a specific and very sensitive technique for the localization of 5-HT within the central nervous system of cephalopod Mollusca.

Expression of mouse semaphorin H mRNA in the inner ear of mouse fetuses.

Semaphorins constitute a large family of secreted and cell-surfaced proteins that appear to function as chemorepellents to guide axons. We examined the expression pattern of M-semaH mRNA in the inner ear of mouse fetuses by in situ hybridization histochemistry. M-semaH mRNA expression was high in the endolymphatic sac involved in endolymph homeostasis. It was also high in the semicircular ducts except for the crista ampullaris, whereas no expression was detected in the epithelium of cochlear ducts.

The biological and clinicopathological characteristics of right-sided colon cancer.

The biological characteristics of right-sided colon cancer were examined in 74 colon cancers with regard to clinicopathological parameters, proliferative activity and p53 expression. Significant differences between right-sided and left-sided colon cancer were found in age, tumor size, histological type and lymphatic vessel invasion. The proliferating cell nuclear antigen labeling index did not significantly differ between the two cancers. The frequency of p53 overexpression was lower in the former than in the latter. The results suggested that right-sided colon cancer did not differ from left-sided colon cancer in proliferative activity except for its tendency to be locally advanced and to differ in carcinogenesis.

Self-reported prevalence of non-insulin-dependent diabetes mellitus in the 1st (Issei) and 2nd (Nisei) generation of Japanese-Brazilians over 40 years of age.

The immigration of Japanese people to Brazil began in 1908 with two major waves, from 1925 to 1940 and from 1952 to the 1960s. Brazil has the largest population (about 1,288,000) of Japanese origin outside Japan with varying age groups. A mortality study revealed that diabetes as an underlying cause of death was higher in the first-generation Japanese than in Japan (3.4 vs. 1.9 per 100,000 for men, and 7.2 vs. 1.9 for women). The self-reported prevalences of known diabetes in subjects aged 40 years or older were obtained by questionnaires from three sources. In six Japanese cultural associations in Säo Paulo city, the prevalences were 9.7% and 6.9% for the first generation (mean age 61.5 years) and for the second generation (mean age 40.0 years), respectively. Age-adjusted prevalences, according to the Brazilian population in the 1980 national census, were 6.9% and 8.1% for the first and second generations. According to a study carried out as a part of a socioeconomic census of the Japanese population in Brazil, the prevalences of diabetes were 7.4% and 5.2%, and the age-adjusted prevalences were 5.3% and 5.8% in the first and second generations, respectively. Another study carried out for employees of a bank, owned by Japanese-Brazilian community members, revealed crude prevalences of diabetes in the first and second generations of 7.1% and 4.2%, and age-adjusted prevalences of 7.3% and 8.2%, respectively. These data indicate an increased prevalence of diabetes in this population compared to Japan, suggesting the importance of environmental factors in the pathogenesis of diabetes.

Can urinary eicosanoids be a potential predictive marker of clinical response to thromboxane A2 receptor antagonist in asthmatic patients?

Thromboxane (TX) A2 is an important bronchoconstrictor in the pathogenesis of asthma. Seratrodast, known as AA-2414, is a new oral TXA2 receptor antagonist which is currently prescribed in asthma therapy in Japan. However its clinical effects have been very different in individual subjects. To assess whether the clinical efficacy of TXA2 antagonist is predictable on the basis of urinary arachidonic acid metabolites in urine of patients with asthma, an open and multicentre trial was conducted. Fifty adult asthmatic subjects (women/men = 28/22) were enrolled [resting mean forced expiratory volume in 1 sec (FEV1)% was 82%; range, 50-96%]. Urinary levels of 11-dehydro-TXB2, leukotriene (LT) E4, 2,3-dinor-6-keto-prostaglandin F1alpha and creatinine in 3-h urine collected in the morning at the start of seratrodast (80 mg day(-1), once a day at evening for 4 weeks) were measured. Responders were defined by improvements of asthma symptoms score and peak expiratory flow rate (PEFR). Of the 50 subjects, 45 completed this study. Eighteen patients were responders and the other 27 were nonresponders. There were no significant differences between the two groups in patients' characteristics, baseline lung functions, treatments and baseline urinary eicosanoids. The 11-dehydro-TXB2/LTE4 ratio of responders was significantly higher (P = 0.0091) than that of non-responders (mean +/- SE, 7.49+/-0.71 vs. 5.09+/-0.67). Eleven patients out of 18 responders agreed to continue this drug for 6 months, the 11-dehydro-TXB2/LTE4 ratio decreased during this period, but not significantly. Our data demonstrated that responders and non-responders to TXA2 receptor antagonist existed in patients with asthma, and it suggests that the ratio of urinary eicosanoids might be a possible predictor of the effects of TXA2 receptor antagonist.

Seroepidemiological survey of distemper virus infection in the Caspian Sea and in Lake Baikal.

Forty Caspian seals were surveyed seroepidemiologically between 1993 and 1998 around the times of mass mortality that occurred in 1997 in the Caspian Sea and seven Baikal seals were also surveyed in 1998. Virus neutralizing tests and ELISA clearly suggested that distemper virus epidemic was caused in Caspian seals before the spring of 1997 and that CDV infection continued to occur in Lake Baikal in recent years.

Indwelling catheter retraction because of pendulous breast.

Long-term home parenteral nutrition (HPN) is an established treatment for chronic intestinal failure. A reliable and safe vascular access is of fundamental importance to HPN patients. We have typically used a right atrial catheter attached to a subcutaneous port. We present a case of right atrial catheter retraction in a large-breasted woman with short bowel syndrome. The catheter was retracted and coiled around the reservoir in the subcutaneous pocket by motion of the patient with large breasts. Displacement of right atrial catheters is a rare but recognized complication. To avoid this complication in obese patients with large breasts, the positional changes of the breast should be determined. and the reservoir should be implanted in the area of least motion along the sternum.