Molecular cloning and mapping of 16S-23S rRNA gene complexes of Staphylococcus aureus

Staphylococcus aureus BB255, a derivative of NCTC8325, had six rRNA operons, and each operon contained two SmaI sites about 3 kb apart. By molecular cloning and pulsed-field gel electrophoresis, all operons were mapped at the junctions of SmaI fragments in the published map of NCTC8325 except one, which was connected to a previously unidentified 23-kb SmaI fragment.

Detection of Theileria sergenti infection in cattle by polymerase chain reaction amplification of parasite-specific DNA

A pair of synthetic oligonucleotide primers, designed from the gene encoding a 32-kDa intraerythrocytic piroplasm surface protein of Theileria sergenti, were used to amplify parasite DNA from the blood of T. sergenti-infected cattle by means of the polymerase chain reaction (PCR). PCR-amplified DNA was examined by electrophoresis and by dot blot or microplate hybridization using a parasite-specific cDNA probe. PCR was specific for T. sergenti, since no amplification was detected with DNA from Anaplasma centrale, Babesia ovata, uninfected erythrocytes, and leukocytes. This method was sensitive enough to detect about 4.5 parasites per microliters of blood with a 10-microliters sample volume. Moreover, of 66 specimens from grazing cattle, 40 were microscopically positive, whereas PCR revealed that 54 samples were positive. Therefore, PCR provides a useful diagnostic tool for detecting T. sergenti-infected cattle, and it is significantly more sensitive than the current methods.

Breast masses with mixed cystic-solid sonographic appearance

Retrospective analysis was performed for 56 breast masses with mixed cystic and solid sonographic patterns encountered in the last 5 years at Keio University Hospital, with the objective of elucidating their significance. The lesions were classified into two major groups: tumor with cyst (TWC--solid mass with cystic component) and intracystic tumor (ICT--cystic mass with solid component). According to the pathological diagnosis, 57% were benign and 43% were malignant. Fifty eight percent of malignant lesions were shown to have a TWC pattern and 42% an ICT pattern. Among benign lesions, 66% were shown to be TWC and 34% ICT. In malignant tumors, 96% of the cases showed irregular shape and heterogeneous internal content. Even in benign lesions, a high incidence of irregular shape and rough border was found, although the predominant internal echo texture was homogeneous, and three-dimensional (3-D) contour was not clear. In conclusion, we observed that in the TWC group, the lack of a defined 3-D contour is the most important criterion, and tumors with multiples cysts tend to be benign.

Growth inhibition of human lung cancer cell lines by interleukin 6 in vitro: a possible role in tumor growth via an autocrine mechanism

It has been considered that growth of human lung cancer cells, like other malignant cells, is positively and negatively regulated by a variety of growth factors via autocrine as well as paracrine mechanisms. The autocrine mechanism is considered to be important in the autonomy of proliferation of cancer cells. Recently, the role of autocrine growth-inhibiting factors such as transforming growth factor beta attracts special attention for better understanding of growth regulation of malignant cells. Here, we have demonstrated that a multifunctional cytokine interleukin 6 (IL-6) had an inhibitory effect on the proliferation of human non-small cell lung cancer cell lines, as shown by the growth accelerating effect of the specific anti-IL-6 antibody as well as the effect of exogenously added IL-6. Moreover, IL-6 can be expressed and released by human lung cancer cells, and these cells had specific IL-6 receptors on their cell surfaces, suggesting an autocrine mechanism. The growth-inhibitory effect of IL-6 was additive to that of transforming growth factor beta, and could not be neutralized by the addition of anti-transforming growth factor beta antibody. These results suggested that IL-6 may function as another class of autocrine growth-inhibiting factor in the growth regulation of human lung cancer. Relatively lower IL-6 sensitivity of these cells than noncarcinogenic human bronchial epithelial cells also suggested that escape from growth regulation by inhibitory factors such as IL-6 could be involved in lung cancer oncogenesis.

Suprasellar embryonal carcinoma which developed ten years after local radiation therapy for pineal germinoma

We recently encountered a case of suprasellar embryonal carcinoma which developed 10 years after local radiation therapy for pineal germinoma. This 29-year-old male was admitted because of abnormal behavior, disturbed consciousness, and increased intracranial pressure. Computed tomography and magnetic resonance imaging disclosed a tumor spreading from the suprasellar region to the third ventricle and the anterior horn of the left lateral ventricle, accompanied by fresh hemorrhage within the tumor. He underwent subtotal removal of the tumor, followed by chemotherapy with cisplatin and etoposide. The tumor was histologically rated as embryonal carcinoma with differentiation into yolk sac tumor and choriocarcinoma.

Ultrastructural and morphometric studies on the peripheral course of the vagus in the domestic fowl, with particular reference to the cholinergic innervation of the pancreas

Cytochemical and morphometric studies were carried out to ascertain the peripheral course of the vagus nerve to the chicken pancreas. Nerve bundles accompanying the left gastric artery were named tentatively the left gastric artery nerve which contained unmyelinated and myelinated nerve fibers showing the acetylcholinesterase positive reaction. After vagotomy various degenerating features were observed in both the unmyelinated and myelinated nerve fibers of the left gastric artery nerve. The ratio of unmyelinated nerve fibers to myelinated nerve fibers decreased significantly following vagotomy, whereas there was no significant difference in the total number of myelinated nerve fibers between the control and vagotomized chickens. Thus, it is hypothesized that the total number of unmyelinated nerve fibers decreases significantly following vagotomy. Our studies yielded the evidence that the left gastric artery nerve contains the unmyelinated nerve fibers derived from the vagus nerve. Moreover, the coeliac plexus showed no significant change in the ratio of unmyelinated to myelinated nerve fibers nor signs of degeneration following vagotomy, although both were observed in the nerve bundles accompanying the pancreatico-duodenal artery. It is, therefore, concluded that a peripheral branch of the vagus nerve runs together with the left gastric and the pancreatico-duodenal arteries, and must innervate the pancreas as the preganglionic nerve fiber.

[Blood flow measurement of renal artery branches, in special reference to interlobular artery by color Doppler]

Blood flow measurement was performed in 58 kidneys of healthy persons. Detection rate, maximum flow velocity (Vmax), pulsatility index (PI) and resistive index (RI) were measured at main renal artery, segmental artery, interlobar artery and interlobular artery with 2 D-Doppler ultrasound machines. Detection rate was highest at interlobar artery. Vmax and PI tended to fall down with arterial branching. Interlobular artery was usually not visualized by color flow mapping, but sometimes well visualized using Acuson machines. Additional measurement of interlobar and interlobular arteries were performed in such 15 cases, and the result was essentially equal to the above mentioned study.

Parathyroid adenoma demonstrated with TI-201 SPECT

A case of parathyroid adenoma with suppressed Tc-99m pertechnetate uptake of the thyroid due to L-thyroxine replacement therapy for hypothyroidism is reported. This case demonstrates successful localization of a parathyroid adenoma in the retrothyroid space using TI-201 SPECT. When the thyroid uptake of Tc-99m pertechnetate is reduced for whatever reason, a planar TI-201 followed by SPECT may be more helpful than TI-201/Tc-99m subtraction scintigraphy.

Distribution of mec regulator genes in methicillin-resistant Staphylococcus clinical strains

The distributions of the mec regulator genes mecI and mecR1, which were identified on the chromosome of mecA-carrying Staphylococcus aureus N315, in methicillin-resistant staphylococci isolated in Japan and various countries were studied. Screening by dot blot hybridization by using polymerase chain reaction (PCR)-amplified probes revealed that at least the 5'-end region of the mecR1 gene was present in all strains tested, whereas about 40% of the strains were negative for the mecI gene. The data suggested that these regulator genes were the original components of the additional mec region DNA of methicillin-resistant S. aureus as well as methicillin-resistant, coagulase-negative staphylococci of seven staphylococcal species (S. epidermidis, S. haemolyticus, S. hominis, S. sciuri, S. capitis, S. caprae, and S. warneri). The mecI gene, which presumably codes for the repressor protein of the mecA gene, was found to harbor a point mutation in all six mecI-positive methicillin-resistant S. aureus strains, and their basal level of mecA gene transcription was elevated compared with that of strain N315, which harbors a presumably intact counterpart of the mecI gene. The data suggested that the mecI gene encodes for a strong repressor function on mecA gene transcription and is deleted or mutated in clinical methicillin-resistant S. aureus strains with high levels of resistance to methicillin.

Isolation of reovirus type 3 from dogs with diarrhea

Three virus strains were isolated in DK cell cultures inoculated with fecal specimens of dogs manifesting diarrhea. The isolates were identified as reoviruses on the basis of their biological and physico- chemical properties. They possessed reovirus type 3 antigenic specificity revealed by hemagglutination-inhibition and neutrarization tests with the reovirus prototype strains. It was suspected that the isolates were participated in this diarrheic cases.

Effects of intraischemic hypothermia on cerebral damage in a model of reversible focal ischemia

Considerable evidence indicates that brain temperature during ischemia affects the extent and distribution of ischemic injury. However, only limited data have been presented concerning the influence of temperature on ischemic damage after reversible focal cerebral ischemia. Because focal ischemic events of this type resemble conditions observed in the clinic, studies were undertaken to examine the effects of mild and moderate hypothermia on the extent of cerebral infarction after focal neocortical ischemia. Under halothane anesthesia, the left middle cerebral artery and both carotid arteries were occluded reversibly for a period of 3 hours in adult Sprague-Dawley rats. The animals were killed 3 days later. Brain sections were stained with triphenyltetrazolium chloride and analyzed for infarction using a computerized image analysis system. Temporal muscle temperature and rectal temperature were monitored continuously. The following groups with different intraischemic temporal muscle temperatures were analyzed: 1) control, 35.8 to 36.2 degrees C; 2) mild hypothermia, 33.0 to 33.5 degrees C; and 3) moderate hypothermia, 27.5 to 29.2 degrees C. The volumes of infarction were 214.5 +/- 17.9, 166.5 +/- 6.8, and 108.2 +/- 5.9 mm3 (mean +/- SEM) for the control, mild hypothermia, and moderate hypothermia groups, respectively. These findings demonstrate that both mild and moderate hypothermia reduce the impact of temporary focal ischemia in Sprague-Dawley rats.

Possible link between a low prevalence of cardiovascular disease and mild dyslipidaemia: a study in Japanese patients with type 2 diabetes

In 98 Japanese patients with Type 2 diabetes mellitus, serum total cholesterol, triglyceride, high density lipoprotein cholesterol (HDL-C), free fatty acid (FFA), and apolipoproteins (apo) A-I, A-II, B, C-II, C-III, and E were determined. The data were compared with those in 47 normolipidaemic normal controls. The total cholesterol value of the diabetic patients was also compared to that of a general population (n = 2227). The diabetic patients were separated into those with cardiovascular disease (n = 20) and without it (n = 78) and a comparison of clinical characteristics and dyslipidaemia was also performed. The diabetic patients had slightly but significantly higher FFA, LDL-C, apo B, C-II, C-III, E, and B/A-I, and lower apo A-I and A-II compared to the normal controls. The total cholesterol level of the diabetic patients (5.17 +/- 0.96 mmol-1) was not significantly higher than that of the general population (5.12 +/- 0.91 mmol-1). By multivariate stepwise discriminant analyses, only total cholesterol significantly discriminated the patients with and without cardiovascular disease. In Japanese patients with Type 2 diabetes, a diabetic population with a very low prevalence of cardiovascular disease, high total cholesterol is a risk factor for developing cardiovascular disease. Nevertheless, a markedly low prevalence of cardiovascular disease in Japanese with Type 2 diabetes compared to Caucasian counterparts may partly be due to the mildness of dyslipidaemia.

Thermal sensitivity of hypoxic responses in neocortical brain slices

Electrophysiological responses to transient hypoxia were studied in neocortical brain slices from adult gerbils. Evoked responses and direct current (DC) potentials were recorded in layer III of the parietal cortex under normoxic and hypoxic conditions. The excitatory synaptic component of the evoked waveform was identified by its sensitivity to calcium and 6,7-dinitroquinoxaline-2,3-dione (DNQX). Under normoxic conditions, hypothermia reduced excitatory synaptic responses in a temperature-dependent manner. Under hypoxic conditions, hypothermia prolonged the delays to synaptic loss and hypoxic depolarization in a temperature-dependent manner. Synaptic recovery following a fixed period under hypoxic depolarization was greatly enhanced when hypoxia was administered at reduced temperature. The findings demonstrate that evoked responses are reduced under hypothermic conditions, but that these responses are sustained for a longer period of time during hypoxia. The data suggest that hypothermia protects against hypoxic damage to excitatory synaptic mechanisms in the neocortex both by prolonging the delay to hypoxic depolarization, and by extending the period of hypoxic depolarization that can be tolerated.

[Advantages of intravascular ultrasound--preliminary experience in patients with peripheral and renal vascular disease]

Intravascular ultrasound (IVUS) is a new method in which endovascular images are obtained from a catheter inserted into an artery. We uses IVUS during PTA of iliac and renal artery, and examined its effectiveness. Three layers are well defined in normal arterial wall. Calcified deposits are recognized as a combination of strong echo and acoustic shadow. The absolute cross sectional area of patent lumen and atherosclerotic plaque can be calculated. IVUS is very effective for the assessment of PTA. The increased caliber of arteries following PTA is caused by the over stretching of the media rather than the compression of atheroma.

Mutations in the rfbT gene are responsible for the Ogawa to inaba serotype conversion in Vibrio cholerae O1

In cultures of Vibrio cholerae strains of Ogawa serotype, variant strains which had undergone serotype conversion from Ogawa to Inaba were identified. The rfbT genes cloned from the parent strains were found to produce a 31-kDa protein in the maxicell system, and to cause serotype conversion when introduced into E. coli cells expressing Inaba serotype specificity. On the other hand, rfbT genes cloned from the variant strains neither produced the 31-kDa protein nor caused serotype conversion. Nucleotide sequence of these rfbT genes as well as those of two clinical Vibrio cholerae strains of Inaba serotype revealed that mutations causing premature termination of their rfbT genes were invariably present in strains expressing Inaba serotype specificity. The results strongly suggested that genetic alteration of the rfbT gene is responsible for serotype conversion of Vibrio cholerae O1.

A reproducible model of reversible, focal, neocortical ischemia in Sprague-Dawley rat

A reproducible model of reversible, focal ischemia was developed for use with the normotensive, Sprague-Dawley rat. Blood flow to the left cerebral hemisphere was interrupted by occluding simultaneously the left middle cerebral artery and both carotid arteries (CCA). The arterial occlusion lasted for 1, 2 or 3 hours after which animals survived for 3 days. The volume of brain infarction was determined utilizing computer-assisted measurements of serial brain sections stained with triphenyltetrazolium. Tissue infarctions of variable size were observed following arterial occlusions which persisted 1 or 2 hours. In contrast, remarkably-consistent infarction size was obtained following a three hours period of occlusion. Tissue edema was also estimated by measuring the volumes of the two hemispheres and expressing these values as a ratio for each animal. The volume ratio was significantly greater in the 3 hour ischemic group, indicating the occurrence of edema in the infarcted hemisphere. These results demonstrate that reversible vascular occlusion in the normal, Sprague-Dawley rat results in consistent amounts of tissue infarction. This approach represents an attractive model system for studying the pathophysiological effects of transient, focal ischemia and for testing the effects of putative, therapeutic strategies.

[A case of alcoholic liver cirrhosis associated with portal vein thrombosis which was successfully treated by TIPS]

We reported a case of 51-year-old man with repeated bleeding from gastroesophageal varices and portal vein thrombosis which were successfully treated by transjugular intrahepatic portosystemic shunt (TIPS) and thrombolysis. We used a flexible tip puncture needle (.038") which was thought to be safer than Colapinto needle (16G).

Comparative sequence analysis of the M gene among rabies virus strains and its expression by recombinant vaccinia virus

Nucleotide sequences and the deduced amino acid sequences of the gene encoding the matrix (M) protein of the Nishigahara and the CVS strains of rabies virus have been determined. The M gene is 609 nucleotides long and is capable of coding for a peptide composed of 202 amino acids. Sequence comparison of these M genes with those of other stains [Pasteur (PV), ERA, Avol] revealed that there is 89.7-91.5% homology at the nucleotide level, and 90.1-92.1% homology at amino acid level, between almost all combinations of these strains. However, in the combinations of the PV and ERA strains, and the virulent CVS and the avirulent CVS-derived Avol strains, much higher homology was observed both at the nucleotide and amino acid levels. The predicted secondary structure and hydropathy profiles also exhibited similar features. Recombinant vaccinia virus containing the M gene was constructed. Sodium dodecyl sulfate (NaDodSO4)-polyacrylamide gel electrophoresis of the precipitates obtained by immune reaction of the recombinant virus-infected cell lysate with a monoclonal antibody against the M protein revealed that electrophoretic mobility of the expressed protein is indistinguishable from that of the authentic M protein from rabies virions.

[CT angiography of the liver]

The diagnostic efficacy of CT arterial portography (CTAP) for the hepatic tumors has been established. We developed the double-phase incremental CTAP (DP-CTAP) using a fast CT scanner, by which the double-phase scanning of the whole liver was made during a single contrast administration. The DP-CTAP was performed in 9 cases of hepatic diseases, and was useful for the lesion detection and improvement of the visualization of the liver vasculatures. The maximum density projection angiogram of the portal and hepatic veins was easily made by DP-CTAP images, and useful for three dimensional understanding of the liver vasculatures and the detection of the vascular abnormalities.

A histochemical study of the distribution of acetylcholinesterase-positive nerves in the goat pancreas

The distribution of acetylcholinesterase (AChE)-positive nerve fibers in the goat pancreas was investigated with histochemical methods at the light- and electron-microscopical level. Intrapancreatic ganglia showing AChE activity were found in the interlobular connective tissue or between acini. AChE-positive nerve fibers were distributed in whole glands and formed perivascular and periinsular plexus. Terminals were identified in both the exocrine and the endocrine tissue. These observations make clear that the cholinergic system is involved in the regulation of both the exocrine and endocrine pancreas in the goat.

Shortening of N1 and P3 latencies in event-related potentials observed coincidentally with clinical improvement during nootropic medication in a demented patient: specific effect of nicergoline

Event-related potentials, measured eight times in a patient in the early stages of dementia, demonstrated that clinical symptoms, especially loss of motivation, improved coincidentally with a shortening of reaction time, N1 latency, and P3 latency during nicergoline medication among three nootropics prescribed. Such a longitudinal study design was considered to be useful for quantifying and objectively comparing effects of various nootropics noninvasively.

Bladder tumor staging: comparison of conventional and gadolinium-enhanced dynamic MR imaging and CT

With computed tomography (CT) and unenhanced magnetic resonance (MR) imaging, stage pT3b extravesical extension and beyond can be diagnosed, but tumors confined to the bladder wall (stages pT1-pT3a) are poorly delineated. To determine whether visualization of such tumors could be improved with gadolinium-enhanced MR imaging, dynamic breath-hold T1-weighted MR images were obtained after intravenous infusion of 0.1 mmol/kg gadopentetate dimeglumine in 79 patients (86 tumors). Conventional MR images, CT scans, and histologic correlation were available in all cases. With dynamic gadolinium-enhanced MR imaging, the mucosa could be distinguished from the muscular layers of the bladder wall. Staging accuracy with this technique was 85% (73 of 86), which was significantly better than with CT (55%; 47 of 86) (P < .005) or conventional MR imaging (58%; 50 of 86) (P < .05). The accuracy of staging the intramural extent (pT1-pT3a) of bladder tumors was thus improved with gadolinium-enhanced dynamic MR imaging.