Odor responses and spontaneous oscillatory activity in tentacular nerves of the terrestrial slug, Limax marginatus

We studied the neural oscillatory activity in the peripheral olfactory system of the tentacles in the terrestrial slug, Limax marginatus, by extracellular recording. Recordings from the cut-ends of the inferior tentacular nerves connected to the inferior tentacular ganglia and sensory epithelia showed spontaneous oscillatory activity at frequencies of 0.1-30 Hz. This spontaneous activity was dominated by the 0.6-6 Hz band. Ethanol odor stimulation decreased the amplitude in the 0.6-6 Hz band and increased those in the 6-15 and 15-30 Hz bands. Antagonists of the gamma-aminobutyric acid (GABA) receptor, bicuculline and picrotoxin, resulted in suppression of spontaneous activity and modulated the odor response in the 0.6-6 Hz band. Our results indicate the involvement of GABA-mediated oscillatory activity in the tentacular nerves in the olfactory processing in molluscs.

Hypopituitarism due to pituitary metastasis of lung cancer: case of a 21-year-old man

A 21-year-old man presented persistent dry cough, general malaise, loss of appetite, decreased sexual desire and double vision. Chest radiograph revealed a mass shadow in the left upper lobe. Histopathological diagnosis of the tumor was squamous cell carcinoma. Brain computed tomography and magnetic resonance imaging revealed a metastasis to the pituitary gland. Hypopituitarism was diagnosed by pituitary function tests. Diabetes insipidus was absent and the function of the posterior lobe of the pituitary gland was preserved. Hypopituitarism due to pituitary metastasis is a rare complication of lung cancer, and has never been reported in a patient as young as 21 years old.

A Morphological Study of Age Changes in Adult Human Auricular Cartilage With Special Emphasis on Elastic Fibers

OBJECTIVE

It is well known that the size of the human auricle increases after it has finished development. The reason why the size of the human auricle continues to enlarge until advanced age after reaching adulthood was investigated by observation of the ultrastructure of elastic fibers in human auricular cartilage.

METHODS

A total of 1958 subjects (966 males and 992 females) were classified into 18 age groups from 0 to 5 years up to 85 years and above by 5-year intervals. Ear length, ear width, and length of ear attachment were measured with calipers. Human auricular cartilage was obtained from 26 subjects (16 males and 10 females) aged 14 to 79 years, stained by orcein, and examined by light and electron microscopy.

RESULTS

Each item of measurement of human auricular size increased significantly with age in both males and females. On morphological examination by light and electron microscopy after orcein staining, elastic fibers in the cartilage were almost homogeneous in diameter and surrounded the cartilage lacuna in bundle-like fashion in young persons, whereas those in elderly persons were heterogeneous in thickness and had many fragments surrounding the territorial matrix. In elderly persons, collagen-like fibers and small vesicles with heterogeneous electron density were frequently observed near elastic bundles around the territorial matrix.

CONCLUSION

Structural changes of auricular cartilage associated with morphological age changes of elastic fibers may be one of the causes of expansion of the auricle after reaching adulthood.

Fine needle aspiration of toxoplasmic lymphadenitis in an intramammary lymph node. A case report

BACKGROUND

Cytologic findings of toxoplasmic lymphadenitis (TL) have been only sporadically reported. Intramammary lymph node is an extremely rare site for TL.

CASE

A 47-year-old, healthy, female presented with a breast tumor, which was aspirated. The cytomorphologic features were interpreted as suggestive of TL. Histopathology of the excisional biopsy specimen and subsequent serologic examination confirmed the diagnosis.

CONCLUSION

We obtained several characteristic findings in aspiration of TL. Of these, epithelioid cell clusters and monocytoid cells were the most diagnostic.

Successful treatment of primary and disseminated human lung cancers by systemic delivery of tumor suppressor genes using an improved liposome vector

Delivery of therapeutic genes to disseminated tumor sites has been a major challenge in the field of cancer gene therapy due to lack of an efficient vector delivery system. Among the various vectors currently available, liposomes have shown promise for the systemic delivery of genes to distant sites with minimal toxicity. In this report, we describe an improved extruded DOTAP:cholesterol (DOTAP:Chol) cationic liposome that efficiently delivers therapeutic tumor suppressor genes p53 and FHIT, which are frequently altered in lung cancer, to localized human primary lung cancers and to experimental disseminated metastases. Transgene expression was observed in 25% of tumor cells per tumor in primary tumors and 10% in disseminated tumors. When treated with DOTAP:Chol-p53 and -FHIT complex, significant suppression was observed in both primary (P < 0.02) and metastatic lung tumor growth (P < 0.007). Furthermore, repeated multiple treatments revealed a 2.5-fold increase in gene expression and increased therapeutic efficacy compared to single treatment. Finally, animal survival experiments revealed prolonged survival (median survival time: 76 days, P < 0.001 for H1299; and 96 days, P = 0.04 for A549) when treated with liposome-p53 DNA complex. Our findings may be of importance in the development of treatments for primary and disseminated human lung cancers.

[Clinical comparison of Chlamydia pneumoniae pneumonia, ornithosis, and Mycoplasma pneumoniae pneumonia]

To elucidate the differences between the clinical aspects of Chlamydia pneumoniae (C. pn) pneumonia and those of two other atypical pneumonias, Chlamydia psittaci (C. ps) pneumonia and Mycoplasma pneumoniae (M. pn) pneumonia, we analyzed the symptoms and laboratory data on the cases of these three types of pneumonia: 46 cases of C. pn pneumonia, 39 cases of C. ps pneumonia, and 131 cases of M. pn pneumonia. C. pn pneumonia was significantly more frequent among the elderly (mean 70 +/- 16 years, p < 0.01) and patients were significantly more likely to be male (76%, p < 0.05). A white blood cell count of over 10,000 was seen in 46% of C. pn pneumonia cases, a higher proportion than those of C. ps pneumonia (15%, p = 0.03) or M. pn pneumonia (18%, p = 0.006) cases. The proportions of patients with these infections who had an elevated GOT or GPT were not significantly different. Maximum body temperature was higher in M. pn pneumonia than in C. pn pneumonia (p = 0.003). Purulent sputa were seen in 44% of C. pn pneumonia cases and 50% of M. pn pneumonia cases, and these rates were higher than that of 13% in C. ps pneumonia cases (p = 0.002, p = 0.004). Dyspnea and anorexia symptoms were the most frequent in C. pn pneumonia cases (24% and 29%, respectively, the highest of all three pneumonias). There were clinical differences between C. pn pneumonia and the other two atypical pneumonias. However, there was some difficulty in differentiating between C. pn pneumonia and typical bacterial pneumonia because mixed infections were common (24%) in C. pn pneumonia cases.

[A case of minocycline-induced eosinophilic pneumonia presenting with multiple white eosinophilic plaques in the tracheobronchial mucosa]

A 45-year-old man was admitted with a severe dry cough and fever. He had been given 100 mg/day of minocycline and other drugs for 9 days to treat hematopyuria. Chest X-ray film showed multiple nodular shadows with diffuse reticular shadows. After all the drugs were discontinued, the fever and the shadows improved, but the severe dry cough persisted. The day 4 bronchofiberscopic findings included multiple white plaques in the tracheobronchial mucosa. Punch biopsy specimens obtained from the white plaques revealed severe eosinophil infiltration, and the eosinophil count in the bronchoalveolar lavage fluid had increased (differential count 23%). After three days of 125 mg/day of methylprednisolone sodium succinate injection therapy, the severe cough, the X-ray shadows and the white plaques disappeared. With a positive result in the lymphocyte migration inhibition test, the patient's condition was diagnosed as minocycline-induced eosinophilic pneumonia.

Smoking-related interstitial lung diseases

Interstitial lung diseases (ILDs) encompass diverse clinicopathological disease entities ranging from idiopathic interstitial pneumonia (IIP) to interstitial pneumonia accompanied by collagen vascular diseases and diseases related to smoking, drug reactions, occupational environments, infections, and malignancies. Our focus is on the smoking-related interstitial lung diseases. Specifically, we focus on reports suggesting that chronic smoking is deeply involved in the disease pathogenesis and on reports suggesting that chronic smoking may influence the clinical course in terms of either disease severity or progression. Pulmonary Langerhans' cell granulomatosis (PLCG), desquamative interstitial pneumonia (DIP), respiratory bronchiolitis with interstitial lung diseases (RB-ILD), interstitial pneumonia associated with rheumatoid arthritis, acute respiratory distress syndrome (ARDS), and idiopathic pulmonary fibrosis (IPF) are covered.

Familial cases of severe measles pneumonia

We report two cases of severe measles pneumonia. Patient 1, a 17-year-old boy who contracted measles in the acute phase of infectious mononucleosis caused by Epstein-Barr virus (EBV), transmitted the disease to patient 2, his father. Both patients presented severe pneumonia with bilateral diffuse micronodular shadows. Diagnoses were established in both patients by antibody titers for measles and reverse transcriptase-polymerase chain reaction (RT-PCR) of blood and throat swab. Multinucleated giant cells with intranuclear inclusion bodies were revealed in the transbronchial lung biopsy (TBLB) specimen of patient 2. Both patients recovered with pulse steroid therapy.

Neuronal components of the superior and inferior tentacles in the terrestrial slug, Limax marginatus

To identify the types of neurons and to infer the patterns of connectivity in slug tentacles, we stained the neurons in the superior and inferior tentacles in the terrestrial slug, Limax marginatus, by backfilling of the tentacular nerves with Lucifer yellow. Four types of stained neurons, '(1) sensory neurons', '(2) gamma cells', '(3) ganglion cells', '(4) lateral cells', were identified both in the superior and inferior tentacles. Three subtypes of the sensory neurons, '(1a) round sensory neurons', '(1b) spindle-shaped sensory neurons', and '(1c) small sensory neurons', were found in the digits. The gamma cells and the ganglion cells were interneurons. Three subtypes of gamma cells, '(2a) round monopolar gamma cells', '(2b) round bipolar gamma cells', and '(2c) large gamma cells', were present in the digits. The ganglion cells were composed of '(3a) monopolar ganglion cells', '(3b) bipolar ganglion cells', and '(3c) elongated ganglion cells'. The monopolar and bipolar types were located both in the tentacular ganglia and digits, whereas the elongated type was present only in the tentacular ganglia. The lateral cells, whose function is unknown, were found in the dermo-muscular sheaths of the tentacles. Our study provides the first description of the neuronal map of inferior tentacles in gastropods. The results showed no differences in the morphological features of stained neurons between the superior and inferior tentacles in L. marginatus.

Complement receptor 3-like immunoreactivity in the light green cells and the canopy cells of the pond snail, Lymnaea stagnalis

We observed CR3-like immunoreactivity in the central nervous system (CNS) and its surrounding peripheral nerves of the pond snail, Lymnaea stagnalis. In the CNS of L. stagnalis, the immunoreactivity presenting meshwork-like structure was detected in some neurosecretory cells, which are the light green cells (LGCs) and the canopy cells (CCs), both controlling the body growth. The immunoreactivity was also observed along the edges of median lip nerves. The immunoreactive regions in the median lip nerves appeared to form the axonal plates, from which the LGCs and the CCs release molluscan insulin-related peptides (MIPs) into the blood. By contrast, no immunoreactivity was detected in other neurosecretory cells or their release sites, for example the caudodorsal cells and the cerebral commissure, which release ovulation hormones. The present findings, therefore, suggested that CR3 expresses only in the neurosecretory cells releasing MIPs in L. stagnalis.

Input-specific targeting of NMDA receptor subtypes at mouse hippocampal CA3 pyramidal neuron synapses

Hippocampal CA3 pyramidal neurons receive synaptic inputs from commissural and associational fibers on both apical and basal dendrites. NMDA receptors at these synapses were examined in hippocampal slices of wild-type mice and GluRvarepsilon1 (NR2A) subunit knockout mice. Electrical stimulations at the CA3 stratum radiatum or stratum oriens activate both commissural and associational (C/A) synapses, whereas stimulations at ventral fimbria mainly activate commissural synapses. Ro 25-6981 and ifenprodil, the GluRepsilon2 (NR2B) subunit-selective NMDA receptor antagonists, suppressed NMDA receptor-mediated excitatory postsynaptic currents (NMDA EPSCs) at the commissural-CA3 synapses on basal dendrites more strongly than those at the C/A-CA3 synapses on apical or basal dendrites. However, glutamate-evoked NMDA receptor currents were reduced by the GluRepsilon1 subunit knockout to a similar extent at both apical and basal dendrites. The GluRepsilon1 subunit knockout also reduced NMDA EPSCs at the C/A-CA3 synapses on basal dendrites, but did not affect NMDA EPSCs at the commissural-CA3 synapses on basal dendrites. These results confirmed our previous findings that NMDA receptors operating at different synapses in CA3 pyramidal cells have different GluRepsilon subunit compositions, and further show that the GluRepsilon subunit composition may be regulated depending on the types of synaptic inputs, even within a single CA3 pyramidal neuron.

Presence of activin signal transduction in normal ovarian cells and epithelial ovarian carcinoma

In this study, we have investigated the expression of inhibin subunits and activin receptors (ActRs) in normal and malignant ovarian cells. Each product of the inhibin subunits (alpha, betaa, betab) and activin receptors (ActRs) amplified by reverse transcription polymerase chain reaction were detected as a single band in human granulosa cells, surface epithelial cells (OSE), and the ovarian cancer cell lines OVCAR 3 and SKOV 3. Western blot analysis was performed using polyclonal antibodies against ActR IIa or IIb peptides based on 13 COOH-terminal amino acids; cultured human granulosa cells were used as a positive control. Using ActR IIa antibody, one major band corresponding to approximately 80 kDa and one minor band corresponding to 105 kDa were observed in the samples. One single band at approximately 60 kDa was detected in OVCAR 3 and a 50 kDa band was detected with ActR IIb antibody in cultured granulosa cell, OSE and SKOV 3. Although no detectable change was induced in Smad 4 mRNA in OVCAR 3, Smad 2 mRNA levels were increased during 48 h treatment with activin A (50 ng ml(-1)). These data provide a better understanding as the first step in the mechanism of action of the activin in the epithelial ovarian carcinoma.

Estriol (E3) replacement improves endothelial function and bone mineral density in very elderly women

We investigated the effects of estriol (E3) on endothelial function and bone mineral density (BMD) in very elderly women. Twenty-four very elderly women (80 +/- 3.5 years old) were administered CaCl2 with or without estriol treatment (2 mg/day) for 30 weeks (hormone replacement treatment [HRT] group vs control group). Endothelium-dependent flow-mediated dilatation (FMD), endothelium-independent dilatation by nitroglycerin of the brachial artery, and BMD were assessed. Levels of plasma lipids and apoproteins were not changed; however, both plasma E3 and E2 were substantially increased (E2, 4.6 to 31.3 +/- 8.1; E3, <5 to 45.3 +/- 7.9 pg/mL) by HRT. The FMD value was also increased by HRT, as were the plasma nitrite/nitrate and cGMP values. The response to nitroglycerin was not changed. The BMD was increased by HRT, but decreased in the control group. There were significant differences between the HRT group and control group after 30 weeks' treatment in the levels of osteocalcin, P1CP, and urinary deoxypiridinoridine. E3 significantly improved BMD by inhibiting bone resorption. Endothelial function was improved in line with the antiatherosclerotic effects. E3 might be effective for use in HRT in elderly patients.

Allelic loss at 1p34, 13q12, 17p13.3, and 17q21.1 correlates with poor postoperative prognosis in breast cancer

Allelic losses of tumor suppressor genes (TSGs), or the chromosomal regions harboring them, in tumor DNA may become useful postoperative prognostic indicators. To examine whether specific allelic losses might correlate with postoperative survival in a 5-year prospective follow-up, we tested tumors from a cohort of 264 breast cancer patients for allelic losses of 18 microsatellite markers representing either a known TSG or a region where genetic alterations are frequent in breast tumors. Patients whose tumors had lost an allele at 1p34, 13q12, 17p13.3, or 17q21.1 had significantly higher risks of postoperative mortality than those whose tumors retained both alleles at those loci (at 1p34, a 5-year mortality rate of 29% among patients with losses vs. 7% with retentions, P = 0. 0008; at 13q12, 31% vs. 10%, P = 0.0062; at 17p13.3, 24% vs. 13%, P = 0.026; and at 17q21.1, 31% vs. 13%, P = 0.0047). Furthermore, combined losses at 13q12 and 17p13.3 increased the predicted postoperative mortality risks by a factor of 9.6 (5-year mortality rate of 42% vs. 5% with retentions, P = 0.0001), and combined losses at 1p34 and 17p13.3 raised the predicted postoperative mortality risks by a factor of 8.6 (27% vs. 3%, P = 0.0064). We conclude that allelic losses at these loci can serve as negative prognostic indicators to guide postoperative management of patients. Genes Chromosomes Cancer 26:134-141, 1999.

Horseshoe crab hemocyte-derived antimicrobial polypeptides, tachystatins, with sequence similarity to spider neurotoxins

Antimicrobial peptides, named tachystatins A, B, and C, were identified from hemocytes of the horseshoe crab Tachypleus tridentatus. Tachystatins exhibited a broad spectrum of antimicrobial activity against Gram-negative and Gram-positive bacteria and fungi. Of these tachystatins, tachystatin C was most effective. Tachystatin A is homologous to tachystatin B, but tachystatin C has no significant sequence similarity to tachystatins A and B. Tachystatins A and B showed sequence similarity to omega-agatoxin-IVA of funnel web spider venom, a potent blocker of voltage-dependent calcium channels. However, they exhibited no blocking activity of the P-type calcium channel in rat Purkinje cells. Tachystatin C also showed sequence similarity to several insecticidal neurotoxins of spider venoms. Tachystatins A, B, and C bound significantly to chitin. A causal relationship was observed between chitin binding activity and antifungal activity. Tachystatins caused morphological changes against a budding yeast, and tachystatin C had a strong cell lysis activity. The septum between mother cell and bud, a chitin-rich region, was stained by fluorescence-labeled tachystatin C, suggesting that the primary recognizing substance on the cell wall is chitin. As horseshoe crab is a close relative of the spider, tachystatins and spider neurotoxins may have evolved from a common ancestral peptide, with adaptive functions.

The expression of MMP-2 and TIMP-2 in patients with primary colorectal adenocarcinoma: correlation with liver metastasis

The expression of MMP-2 and TIMP-2 was examined immunohistochemically in a total of 36 colorectal cancer patients with synchronous liver metastasis at the time of surgery, and the serum MMP-2 and TIMP-2 levels were also measured in a total of 58 colorectal cancer patients with/without liver metastasis following primary colorectal surgical resection for serological comparison. Although MMP-2 exhibited a significant expression immunohistochemically in the primary colorectal cancer (p<0.05) and TIMP-2 in the synchronous liver metastasis (p<0.01), there was no relationship between the absence/presence of liver metastasis and serum MMP-2 and TIMP-2 levels, respectively. These results suggest that it can be considered difficult to use serum MMP-2 and TIMP-2 levels to predict the status of liver metastasis following primary resection in patients with colorectal adenocarcinoma.

Effects of total parenteral nutrition on endotoxin translocation and extent of the stress response in burned rats

Postburn endotoxin translocation has been well documented. However, the relationship between the secretion of catabolic hormones, degree of endotoxin translocation, and intestinal atrophy has not been previously demonstrated. In this experiment, modulation of the secretion of catabolic hormones according to the route of nutrient administration was examined in burned animals. A total of 55 rats, with and without a burn injury, were orally or parenterally fed. Urinary excretion of epinephrine and norepinephrine (U-EN) of each rat was measured for 48 h after burn injury as an indicator of the stress response. Evaluations of intestinal atrophy and endotoxin contents in the liver and spleen were also done 48 h after burn injury. U-EN after burn injury in rats administered total parenteral nutrition (TPN) was higher than in those fed orally. Endotoxin translocation and intestinal atrophy after thermal injury were also augmented by TPN. A significant positive correlation between U-EN and endotoxin content of the liver, and a negative correlation between U-EN and weight of the intestine, were observed. TPN enhances the stress response after burn injury. An increase in endotoxin translocation and intestinal atrophy by TPN are closely related to enhancement of the stress response.

Physiological characterization of lip and tentacle nerves in Lymnaea stagnalis

The lip and tentacle nerves of the pond snail, Lymnaea stagnalis, were characterized using electrophysiological techniques. When the activity of those nerves was induced in lip-tentacle preparations, aversive taste signals were transmitted through all the lip and tentacle nerves, but appetitive signals could be recorded only through the superior lip nerve. In the CNS immersed in high Mg2+ -high Ca2+ saline, electrical stimuli applied to any of the nerves failed to induce action potentials in one of the regulatory neurons (cerebral giant cell: CGC) involved in feeding responses, implying that the signals are polysynaptically transmitted to the CGC. Intracellular recordings revealed that the CGCs in semi-intact half-body preparations received both appetitive and aversive taste signals not only through the superior lip nerve but also through the median lip nerve. In addition, an osphradium was ruled out as a candidate for appetitive reception. The present results, together with our preceding data arrived at by the histochemical analyses, indicate that the appetitive taste transduction responsible for generating feeding responses is performed through the superior lip nerve with some contribution of the median lip nerve. The data showing that the CGC can receive various taste signals suggests that it may play a crucial role in feeding behavior as demonstrated in the study of conditioned taste-aversion.

Effect of intravenous omega-6 and omega-3 fat emulsions on nitrogen retention and protein kinetics in burned rats

The effect of omega-3 fat emulsion on nitrogen retention and kinetics in relation to fatty acid profile were investigated in burned rats receiving total parenteral nutrition (TPN). A fat emulsion of a structured symmetrical triacylglycerol containing only eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (2:1) was prepared. Sprague-Dawley rats were fed by fat-free chow for 2 wk. Then rats were fed exclusively with one of three types of TPN for 7 d. Animals in group C received fat-free TPN (n = 11). Group omega 6 received safflower oil fat emulsion, which accounted for 20% of total caloric intake (n = 11). Group omega 3 received fat emulsion containing only EPA and DHA (1% of total calories, n = 11), in addition to safflower oil emulsion (19% of total calories). On day 5, each rat was subjected to 20% full-thickness scald burns. Rats were sacrificed under ether anesthesia 48 h after burning. The rats in group C became deficient in omega-6 essential fatty acids. Cumulative nitrogen balance was decreased significantly in group omega 6. The rates of whole-body protein synthesis were increased significantly in both groups omega 6 and omega 3. In omega 6, however, the rates of whole-body protein breakdown were increased significantly. In conclusion, the rates of whole-body protein breakdown increased and nitrogen retention was aggravated significantly in animals administered the safflower oil emulsion. Significant increases of urinary excretion of total catecholamine were also observed. Prostaglandin E2 and thromboxane B2 concentrations were not significantly different among three groups. Supplementation with the new omega-3 fat emulsion, however, improved protein metabolism in burned rats receiving TPN.

[Vibrio vulnificus infection: clinical and bacteriological analysis of four cases]

Vibrio vulnificus (V. vulnificus) infection has recently been drawing attention as a high mortality disease especially in a patient with the preexisting chronic liver disease. The illness caused by V. vulnificus is divided into three groups such as primary septicemia, wound infection and gastrointestinal illness. Primary septicemia, which is the most common in Japan, is defined as a systemic illness presenting fever or hypotension with recovery of V. vulnificus from blood or tissue without the apparent primary focus of infection. We diagnosed four cases as infectious diseases of V. vulnificus by isolating it from each clinical material in Kurashiki Central Hospital from 1984 through 1997. We investigated clinical manifestations of the four cases including season of the onset, presence of drinking habit, underlying diseases, consumption of raw seafood, symptoms, presence of disseminated intravascular coagulation (DIC) or shock, laboratory data, administered antibiotics and the outcomes of the treatment. And for each strain, we also performed in vitro drug susceptibility tests. The age of the patients ranged from 49 to 61 years old (mean 56), and all of the patients were male. Each of them had a chronic liver disease as an underlying disease. Two of them had a history of raw seafood consumption prior to the onset of the illness. Skin manifestations appeared in two of the four patients. All the patients complicated septic shock and DIC. V. vulnificus was isolated from the venous blood cultures of them. Three of the four were given a diagnosis of primary septicemia and one was made a diagnosis of acute cholecystitis which has never been reported previously. Three of the four patients died and only the rest was alive as a result of antimicrobial therapy. In the sensitivity tests, the four strains were revealed to be very sensitive to the antimicrobials such as minocycline, cephalosporins of the third generation and carbapenems. Once patients with a chronic liver disease are infected with V. vulnificus, their prognosis is poor. Every effort should be made to advise not to have uncooked seafood. Physicians should be informed about the characteristics of the disease caused by this bacteria and treat any suspicious case promptly and appropriately.

Histological characterization of lip and tentacle nerves in Lymnaea stagnalis

The lip and tentacle nerves of the pond snail, Lymnaea stagnalis, were characterized using histological techniques. Anatomical drawings showed the detailed distributions of the superior lip, median lip, and tentacle nerves in the lip and tentacle; in particular it was found that the mouth is mainly innervated by the superior lip nerve. The tentacle nerve was clarified to form a zigzag structure along the extension direction in a shrinking tentacle. By backfilling of the superior lip nerve and/or the median lip nerve with fluorescent dyes, the neurons in the CNS made some clusters, whereas those stained from the tentacle nerve made other clusters. These stained neurons were not part of the central pattern generator or its regulatory neurons for feeding. The present results, therefore, suggest that the superior lip nerve may be employed as a principal factor in the chemosensory transduction from the mouth, and that no direct inputs occur through the lip and tentacle nerves to the central pattern generator or its regulatory neurons for feeding.

Effects of electrical stimulation of the tentacular digits of a slug upon the frequency of electrical oscillations in the procerebral lobe

To find the primary mechanism for the frequency changes of electrical oscillations in the procerebral (PC) lobe of a slug, we electrically stimulated the tip, middle and basal regions of the digits of the superior and inferior tentacles and recorded the local field potentials from the PC lobe. Stimuli to the middle and basal regions of the digits of the inferior tentacle significantly decreased the frequency of electrical oscillations in the PC lobe, whereas those to the tip regions of the digits of the inferior tentacle and all regions of the digits of the superior tentacle increased it. These findings suggest that the change in the frequency of electrical oscillations in the PC lobe depends on the excited region in the digits, providing the first presentation of the physiological difference in the olfactory function between the superior and inferior tentacles.

[Multicenter screening of Chlamydia pneumoniae pneumonia by ELISA method]

We prospectively investigated the etiology of community-acquired pneumonia among adult patients admitted to three general hospitals over one year. Antibody titers to Chlamydia pneumoniae were also measured by ELISA method to investigate the incidence and clinical pictures of C. pneumoniae pneumonia in Japan. Two hundred and fourteen patients were enrolled in the study. Seventeen patients (7.9%) satisfied the criteria for diagnosis of acute infection due to C. pneumoniae by ELISA method. C. pneumoniae was the 3rd leading causative agent following Streptococcus pneumoniae (21.5%) and Haemophilus influenzae (8.4%). Preexisting antibodies were detected in 62.1% of the patients. Most of the patients with C. pneumoniae pneumonia were aged, and had comorbidities of respiratory system. Superinfection with bacterial pneumonia was recognized in some patients. Though there are several problems, ELISA method is thought to be useful to diagnose C. pneumoniae pneumonia, and is suitable for screening tests.