Inhibition of RhoA reduces propofol-mediated growth cone collapse, axonal transport impairment, loss of synaptic connectivity, and behavioural deficits.

BACKGROUND: Exposure of the developing brain to propofol results in cognitive deficits. Recent data suggest that inhibition of neuronal apoptosis does not prevent cognitive defects, suggesting mechanisms other than neuronal apoptosis play a role in anaesthetic neurotoxicity. Proper neuronal growth during development is dependent upon growth cone morphology and axonal transport. Propofol modulates actin dynamics in developing neurones, causes RhoA-dependent depolymerisation of actin, and reduces dendritic spines and synapses. We hypothesised that RhoA inhibition prevents synaptic loss and subsequent cognitive deficits. The present study tested whether RhoA inhibition with the botulinum toxin C3 (TAT-C3) prevents propofol-induced synapse and neurite loss, and preserves cognitive function. METHODS: RhoA activation, growth cone morphology, and axonal transport were measured in neonatal rat neurones (5-7 days in vitro) exposed to propofol. Synapse counts (electron microscopy), dendritic arborisation (Golgi-Cox), and network connectivity were measured in mice (age 28 days) previously exposed to propofol at postnatal day 5-7. Memory was assessed in adult mice (age 3 months) previously exposed to propofol at postnatal day 5-7. RESULTS: Propofol increased RhoA activation, collapsed growth cones, and impaired retrograde axonal transport of quantum dot-labelled brain-derived neurotrophic factor, all of which were prevented with TAT-C3. Adult mice previously treated with propofol had decreased numbers of total hippocampal synapses and presynaptic vesicles, reduced hippocampal dendritic arborisation, and infrapyramidal mossy fibres. These mice also exhibited decreased hippocampal-dependent contextual fear memory recall. All anatomical and behavioural changes were prevented with TAT-C3 pre-treatment. CONCLUSION: Inhibition of RhoA prevents propofol-mediated hippocampal neurotoxicity and associated cognitive deficits.

Alterations in 18F-FDG accumulation into neck-related muscles after neck dissection for patients with oral cancers.

BACKGROUND: 18F-fluoro-2-deoxy-D-glucose (18F-FDG) accumulations are commonly seen in the neck-related muscles of the surgical and non-surgical sides after surgery with neck dissection (ND) for oral cancers, which leads to radiologists having difficulty in diagnosing the lesions. To examine the alterations in 18F-FDG accumulation in neck-related muscles of patients after ND for oral cancer. MATERIAL AND METHODS: 18F-FDG accumulations on positron emission tomography (PET)-computed tomography (CT) in neck-related muscles were retrospectively analyzed after surgical dissection of cervical lymph nodes in oral cancers. RESULTS: According to the extent of ND of cervical lymph nodes, the rate of patients with 18F-FDG-PET-positive areas increased in the trapezius, sternocleidomastoid, and posterior neck muscles of the surgical and/or non-surgical sides. In addition, SUVmax of 18F-FDG-PET-positive areas in the trapezius and sternocleidomastoid muscles were increased according to the extent of the ND. CONCLUSIONS: In evaluating 18F-FDG accumulations after ND for oral cancers, we should pay attention to the 18F-FDG distributions in neck-related muscles including the non-surgical side as false-positive findings.

Intraoperative detection of viable bone with fluorescence imaging using Visually Enhanced Lesion Scope in patients with bisphosphonate-related osteonecrosis of the jaw: clinical and pathological evaluation.

UNLABELLED: There is no standard surgical protocol of bisphosphonate-related osteonecrosis of the jaws (BRONJ), because of the impossibility to visualize this feature intraoperatively. The aim of this study was to introduce how to provide preoperative labeling of the viable bone with minocycline bone fluorescence technique (MBFT) by using VELscope® and investigate histopathologically. INTRODUCTION: The American Association of Oral and Maxillofacial Surgeons (AAOMS) and the Japanese Society of Oral and Maxillofacial Surgeons (JSOMS) now recommend a more conservative treatment strategy. There is no standard surgical protocol of bisphosphonate-related osteonecrosis of the jaws (BRONJ) because of the impossibility to visualize this feature intraoperatively. The aim of this study was to introduce a mechanism providing preoperative labeling of a viable bone using minocycline bone fluorescence technique (MBFT) with VELscope® and to histopathologically investigate. METHODS: This report describes a surgical technique used in six patients with BRONJ who underwent jawbone resection under minocycline bone fluorescence imaging using VELscope®. Subsequently, we investigated and compared the clinical findings using VELscope® and histopathological findings. RESULTS: Histopathological examinations showed that the non-fluorescent moiety was consistent with the BRONJ lesions. CONCLUSIONS: The surgical treatments that were exactly performed using MBFT with VELscope® offered successful management of BRONJ. This bone fluorescence helped to define the margins of resection, thus improving surgical therapy for extended osteonecrosis.

Clinical relevance of cagPAI intactness in Helicobacter pylori isolates from Vietnam.

The purpose of this paper is to investigate the relationship between clinical outcome and the intactness of cagPAI in Helicobacter pylori strains from Vietnam. The presence or absence of 30 cagPAI genes was investigated by polymerase chain reaction (PCR) and dot-blotting. H. pylori-induced interleukin-8 secretion and hummingbird phenotype, and H. pylori adhesion to gastric epithelial cells were examined. The serum concentration of pepsinogen 1, pepsinogen 2, and gastrin was also measured in all patients. cagPAI was present in all 103 Vietnamese H. pylori isolates, of which 91 had intact cagPAI and 12 contained only a part of cagPAI. Infection with the partial cagPAI strains was less likely to be associated with peptic ulcer and chronic gastric mucosal inflammation than infection with strains possessing intact cagPAI. The partial cagPAI strains lacked almost all ability to induce interleukin-8 secretion and the hummingbird phenotype in gastric cells. Their adhesion to epithelial cells was significantly decreased in comparison with intact cagPAI strains. Moreover, for the first time, we found an association between cagPAI status and the serum concentration of pepsinogens 1 and 2 in infected patients. H. pylori strains with internal deletion within cagPAI are less virulent and, thus, less likely to be associated with severe clinical outcomes.

Can MRCP replace ERCP for the diagnosis of autoimmune pancreatitis?

BACKGROUND: It is of utmost importance that autoimmune pancreatitis (AIP) be differentiated from pancreatic cancer. Irregular narrowing of the main pancreatic duct is a characteristic finding in AIP; it is useful for differentiating AIP from pancreatic cancer stenosis. This study evaluated the usefulness of magnetic resonance cholangiopancreatography (MRCP) for the diagnosis of AIP and assessed whether MRCP could replace endoscopic retrograde cholangiopancreatography (ERCP) for diagnosing AIP. METHODS: The MRCP and ERCP findings of 20 AIP patients were compared. RESULTS: On MRCP, the narrowed portion of the main pancreatic duct was not visualized, while the noninvolved segments of the pancreatic duct were visualized. The degree of upstream dilatation of the proximal main pancreatic duct was milder in AIP than in pancreatic cancer patients. In the skipped type, only skipped narrowed lesions were not visualized. After steroid therapy for AIP, the nonvisualized main pancreatic duct became visualized. CONCLUSIONS: MRCP cannot replace ERCP for the diagnosis of AIP, since narrowing of the main pancreatic duct in AIP was not visualized on MRCP. MRCP findings of segmental or skipped nonvisualized main pancreatic duct accompanied by a less dilated upstream main pancreatic duct may suggest the presence of AIP. MRCP is useful for following AIP patients.

Alternaria brassicae produces a host-specific protein toxin from germinating spores on host leaves.

Spore suspensions of Alternaria brassicae, the causal agent of gray leaf spot in Brassica plants, were incubated on the leaves of cabbage (B. oleracea) and spore germination fluid (SGF) was collected after 48 h. A high molecular weight (HMW) fraction (>10 kDa) was separated from the SGF by ultrafiltration. In a detached leaf assay, the HMW fraction induced visible symptoms only on host leaves and the toxicity was lost by treatment with proteinase K or heat at 60 degrees C for 15 min, indicating the presence of host-specific protein toxin(s). A protein toxin in the HMW fraction was purified by several chromatography steps. The toxin induced water-soaked symptoms followed by chlorosis at concentrations of 0.5 to 1 microg/ml on host leaves, but not on nonhost leaves even at 50 microg/ml. The toxin also had infection-inducing activity when added to spore suspension of a nonpathogenic isolate of A. alternata, causing symptoms similar to the infection of A. brassicae only on host leaves. These results indicate that a new host-specific protein toxin named ABR-toxin is released from germinating spores of A. brassicae on host leaves. ABR-toxin migrated as a protein of 27.5 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isoelectric point of ABR-toxin was estimated to be approximately 7.0 and 21 N-terminal amino acid residues were sequenced.

Expression of coxsackievirus and adenovirus receptor in hearts of rats with experimental autoimmune myocarditis.

The expression of coxsackievirus and adenovirus receptor (CAR) was dominant in the brains and hearts of mice until the newborn phase. There is no detailed information concerning the relation between the expression of CAR and development of hearts. It is also uncertain whether CAR is able to be induced in adult hearts after cardiac injury. We demonstrated that CAR was abundant in the hearts of newborn rats but was barely detectable in the hearts of adult rats. The expression of CAR in rat hearts with experimental autoimmune myocarditis, which was induced by immunization of purified cardiac myosin, was serially investigated. Active myocarditis was observed from day 15 after immunization. By immunohistochemistry, cardiomyocytes were strongly stained for CAR antibody from days 24 to 42. CAR mRNA was also detected from days 18 to 30 by using reverse transcription-polymerase chain reaction. In the next experiment, the induction of CAR on isolated cardiomyocytes was investigated. CAR was barely detectable in cultured cardiomyocytes by Western blot analysis after isolation. This molecule gradually appeared along with the creation of clusters and beating of cardiomyocytes. Furthermore, the induction of CAR in cultured cardiomyocytes increased after supplement with conditioned medium of rat splenocytes activated by concanavalin A. In conclusion, rat CAR is expressed strongly in the hearts of newborn rats and is suppressed in those of adult rats. The expression of CAR is enhanced during the active phase of experimental autoimmune myocarditis and is induced by inflammatory mediators. CAR may play a role in cell-to-cell contact and adhesion of cardiomyocytes.

Hormonal status of breast cancer. I. Thoretical basis for the analysis of steroid profile.

Gas-liquid chromatography was applied to the analysis of urinary steroids of women. In the statistical analysis, quantitation of all steroid excretions and ratios among them were transformed to give a normal frequency distribution. The influence of the host's age and the menstrual cycle on 24 hours' excretion was investigated for each of 14 identified neutral steroids, of which four in our fraction 2 (11-hydroxyandrosterone, 11-hydroxyetiocholanolone, pregnanediol, and pregnanetriol) were menstruation dependent. The 14 neutral steroid excretions were generally correlated with one another within the host, and the use of a steroid ratio rather than quantitation of steroid excretion was often more sensitive in the characterization of the hormonal status.

Enhancing effect of hydrocortisone acetate administration on the content of A-type particles in Ehrlich ascites tumor.

The incidence of intracytoplasmic A-particles was investigated in neoplastic and nonneoplastic cells of Swiss/ICR mice. The concentration of the virus-like particles decreased in the order of 1) invasive Ehrlich 4N ascites clone 1 tumor, 2) noninvasive Ehrlich 4N ascites clone 3 tumor, and 3) nonneoplastic cells of tumor-free mice. Four successive injections of hydrocortisone acetate, 1 mg/day/mouse, when administered after tumor inoculation, almost tripled the cellular content of A-particles in Ehrlich clone 1 tumor (P less than .001), whereas the same treatment given before tumor inoculation did not affect the particle content. The enhancing effect of the hormone was found to be dose-dependent (P = .0027). Possibly, hydrocortisone acetate accelerates the formation of A-particles by stimulating directly the virus-generating apparatus of clone 1 tumor cells.

Hormonal status of breast cancer. III. Further analysis of ovarian-adrenal dysfunction.

Detailed studies of urinary steroids in patients with breast cancer and normal controls have shown that abnormal aging processes and depressed corpus luteum function were associated with the presence of this form of cancer. The ratio of androsterone to tetrahydrocortisol, an index of the aging process, was significantly lower in a breast cancer group than in a normal group at both premenopausal and postmenopausal stages. In premenopausal women, the ratio decreased in the order of rural controls, urban controls, and patients with breast cancer. It was indicated that the ratio may serve as a measure of risk for breast cancer. Aside from the general depression of menstruation-dependent steroids, breast cancer was associated with disproportionately low excretions of prenanediol and pregnanetriol within the menstruation-dependent steroid family. The notion that this finding reflects the delay or complete failure of ovulation was supported by a reduced parturition rate of our patients with breast cancer as compared with that of our normal controls. The physiologic significance of steroidal disturbances was considered in relation to the genesis of breast cancer.

Relationship between epidemiologic and endocrinologic aspects of cervical cancer.

In search of etiologic relevancy of the steroid deviations in urine, we compared the reproductive activities of patients having cervical cancer with those of normal controls. A premenopausal patient experienced the birth of her first child significantly earlier than did the urban control of corresponding age, despite their similarity of age at menarche. However, when the same patient was compared with the premenopausal rural control, this differences was not found. The same parameter also failed to differentiate a postmenopausal patient from the corresponding control of urban origin. The premenopausal patient who was indistinguishable from the rural control by age at first delivery was distinguished from the rural control by reduced excretions of adrenal steroids including 11-deoxy-17 ketosteroids and some corticosteroid metabolites. The spectrum and the degree of deviation of urinary steroids for a patient coincided with the spectrum and the degree of age dependency of the urinary steroids for a normal woman during and after adolescence. These findings indicated that the inability of the reproductive parameter to discriminate a patient was associated with growth retardation in a population, and a maturation deficiency of the adrenal gland (arrest of adrenarche) was implicated in the genesis of cervical cancer.

Hormonal status of breast cancer. II. Abnormal urinary steroid excretion.

The urinary excretion of 14 neutral steroids was measured by gas-liquid chromatography in women with early and advanced breast cancer, in women with early uterine cancer, and in healthy women from urban and rural districts. The premenopausal patients with early breast cancer excreted subnormal amounts of five steroids (11-hydroxyandrosterone, 11-hydroxyetiocholanolone, pregnanediol, pregnanetriol, and tetrahydrocorticosterone) and increased amounts of tetrahydrocortisol as compared with the normal subjects of corresponding ages. From our findings, a new parameter was proposed by which a premenopausal breast-cancer patient was separated from the control. Postmenopausal breast-cancer patients excreted greater amounts of five steroids (one steroid from 17-ketosteroids and four from 17-hydroxycorticoids) than the corresponding controls. The discrepancy between premenopausal and postmenopausal breast cancer was tentatively related to ovarian-adrenal dysfunction in the course of aging. Oophorectomy induced a long-lasting tumor regression only in patients with a high value for the ratio of 11-deoxy-17-ketosteroid to 17-hydroxycorticosteroid in urine taken before surgery; the ratio in the responsive patients decreased remarkably after surgery. A constitutional change in 17-ketosteroids, as observed in a postmenopausal breast-cancer patient and a premenopausal healthy woman of urban origin, favored the geographic importance in the genesis of breast malignancy. The steroid abnormalities in uterine cancer were distinguishable from those of breast cancer in both premenopausal and postmenopausal women.

Enhancing effect of hydrocortisone on hematogenous metastasis of Ehrlich ascites tumor in mice.

The effect of hydrocortisone on blood-borne tumor metastasis was studied in an i.v. inoculation experiment with Ehrlich hypotetraploid clone 1, Ehrlich hypotetraploid stock, and Ehrlich hyperdiploid stock tumors. The administration of hydrocortisone before tumor inoculation resulted in increased tumor take, reduced mean survival time of mice, and concentration of tumor metastasis in a specific organ (i.e., lung metastasis for Ehrlich hypotetraploid clone 1 tumor, and liver metastasis for Ehrlich hypotetraploid stock and Ehrlich hyperdiploid stock tumors). Enhancement of tumor metastasis, as induced by hydrocortisone pretreatment, was not reproduced by the administration of 6-mercaptopurine, testosterone, or estradiol. The progress of tumor death in hydrocortisone-conditioned mice was not affected by either heparin or dextran sulfate. This indicated that the effect of hydrocortisone on tumor metastasis was independent of the effect of these agents on immune reaction or blood coagulation. In the tracer experiment with 125-I-labeled tumor cells, hydrocortisone pretreatment significantly increased over the control the intrapulmonary retention of Ehrlich hypotetraploid clone 1 tumor cells from 1 through 72 hr after tumor inoculation, the time lag required for the establishment of metastatic foci in the lung. The arrest of Ehrlich hypotetraploid stock and Ehrlich hyperdiploid stock tumors in the liver was also temporarily increased by hydrocortisone pretreatment. No correlation was found between tumor cell size and differential distribution of metastatic tumors with 3 Ehrlich tumors. An attempt was made to use this blood-borne metastasis system for chemotherapeutic study. Administration of cyclophosphamide gave rise to a significant prolongation of survival time and often to complete prevention of tumor metastasis in hydrocortisone-conditioned mice.

Maxillary single-jaw surgery combining Le Fort I and modified horseshoe osteotomies for the correction of maxillary excess.

A modified technique of horseshoe osteotomy combined with Le Fort I osteotomy for superior and posterior repositioning of the maxilla is presented. Eight patients with maxillary excess associated with retrogenia or microgenia were treated with this technique in combination with genioplasty. The maxillary segment was repositioned a maximum of 5.0mm posteriorly and 7.0mm superiorly at point A. The mandible autorotated anterosuperiorly to achieve sound occlusion. Point B moved 2.0-10.0mm anteriorly and 5.0-10.0mm superiorly. The pogonion moved 7.0-17.0mm anteriorly in combination with genioplasty. All patients obtained sound occlusion and a good profile after the operation. Almost no skeletal relapse was observed during 1 year of postoperative follow-up. Patients with long faces with maxillary excess and retrogenia often have small, unstable condyles. In these cases, because surgical intervention to the ramus can result in postoperative progressive condylar resorption, maxillary single-jaw surgery with a horseshoe osteotomy, thereby avoiding ramus intervention, is a less invasive option.

Crystalline cylindrical structures of Na(+)-bound dimyristoylphosphatidylglycerol as revealed by microcalorimetry and electron microscopy.

Multilamellar vesicles of dimyristoylphosphatidylglycerol (DMPG) in an aqueous medium of 1 M NaCl at pH 7.0 converted to defined cylindrical structures of crystalline phase, on annealing of 5 degrees C of a gel phase temperature. The new crystalline phase transformed into the liquid crystal phase at a transition point (44.2 degrees C) nearly the same as that of the protonated DMPG, but with a transition enthalpy (19.2 kcal/mol) larger than that of the Ca(2+)-bound DMPG of much higher transition temperature. Electron microscopic observations revealed that a set of outer membranes (8-10 lamellae) separated from the MLV grows into helical structures and, finally, into the crystalline cylindrical structures with an increase in annealing time.

Calorimetric investigations of phase transitions of sonicated vesicles of dimyristoylphosphatidylcholine.

The process of conversion of large multilamellar vesicles (MLVs) of dimyristoylphosphatidylcholine (DMPC) into the final state of small unilamellar vesicles (SUVs) with an increase in time length of ultrasonic irradiation was investigated by calorimetry and negative-stain electron microscopy. The process was found out to be composed of two stages depending on the primary (near 24 degrees C) and secondary (near 19 degrees C) peaks due to the gel-to-liquid crystal phase (Tm) transition, respectively; a new transition peak for the secondary Tm appears after a maximum broadening of the primary Tm peak is attained. Sonicated vesicles characterized by the primary peak of the broadest shape were observed to be about 200 nm in mean diameter and mostly four or so lamellae, and have an internal aqueous space, in contrast to sonicated SUVs (approx. 40 nm in diameter) characterized by the limiting secondary Tm peak. Thermal data associated with the Tm transition for these two sonicated vesicles were compared with that of the MLV. The enthalpy and entropy changes and cooperative units increased in the order sonicated SUV < sonicated large vesicle < MLV. Furthermore, the enthalpy changes were revealed to fairly differ between the sonicated large vesicle and SUV. Based on the effect of the annealing treatment at -5 degrees C on these vesicles the present result suggested a large contribution of the aggregation state of DMPC molecules to the enthalpy possessed by the vesicles of a gel phase temperature, which is related to the mode of the Tm transitions, primary and secondary.