The influence of induction speed on the frontal (processed) EEG.

The intravenous injection of the anaesthetic propofol is clinical routine to induce loss of responsiveness (LOR). However, there are only a few studies investigating the influence of the injection rate on the frontal electroencephalogram (EEG) during LOR. Therefore, we focused on changes of the frontal EEG especially during this period. We included 18 patients which were randomly assigned to a slow or fast induction group and recorded the frontal EEG. Based on this data, we calculated the power spectral density, the band powers and band ratios. To analyse the behaviour of processed EEG parameters we calculated the beta ratio, the spectral entropy, and the spectral edge frequency. Due to the prolonged induction period in the slow injection group we were able to distinguish loss of responsiveness to verbal command (LOvR) from loss of responsiveness to painful stimulus (LOpR) whereas in the fast induction group we could not. At LOpR, we observed a higher relative alpha and beta power in the slow induction group while the relative power in the delta range was lower than in the fast induction group. When concentrating on the slow induction group the increase in relative alpha power pre-LOpR and even before LOvR indicated that frontal EEG patterns, which have been suggested as an indicator of unconsciousness, can develop before LOR. Further, LOvR was best reflected by an increase of the alpha to delta ratio, and LOpR was indicated by a decrease of the beta to alpha ratio. These findings highlight the different spectral properties of the EEG at various levels of responsiveness and underline the influence of the propofol injection rate on the frontal EEG during induction of general anesthesia.

Chirp rate is independent of male condition in a synchronising bushcricket.

Males of the bushcricket Mecopoda elongata synchronise their chirps with neighbouring males, but because synchrony is imperfect, one male's chirp preceeds the other by some 50-200 ms. Since a male's intrinsic chirp rate is critical for the establishment of the leader role in a duet, and females prefer the leader in a choice situation, we investigated a possible condition dependence of this male trait. In a duet leader males are usually those calling at a higher intrinsic rate; therefore, we investigated whether calling at a higher rate indicates male condition. The calling metabolism was quantified in a respirometer; the factorial slope of males calling at a high rate was three times higher compared to males calling at lower rates. Males produce on average 3.4 singing bouts/per night, and there is a significant increase in chirp periods (CPs) with successive singing bouts. Call properties were investigated throughout a male's life; chirp period increases significantly with age. Two groups of males were reared on either a low- or a high-nutrition diet, and the influence of male condition on different song parameters was investigated. CPs in two feeding regimes did not differ significantly, although males of the low-nutrition diet group were significantly affected by nutrition with respect to mortality, a delayed last moult and reduced weight as adults. We therefore conclude that solo chirp rates do not reflect phenotypic male condition properly.

Digital imaging microscopy of firefly luciferase activity to directly monitor differences in cell transduction efficiencies between AdCMVLuc and Ad5LucRGD vectors having different cell binding properties.

The luciferase reporter gene incorporated into adenoviral vectors is very useful for monitoring viral transduction of different cell types or for comparing the transduction efficiency of different viral constructs of one cell type. Luciferase protein expression can be detected and quantified with very high sensitivity from whole cells or organ extracts. However, its disadvantages become obvious when aiming at evaluation of transduction events at the single cell level. The results obtained from whole cell extracts cannot be directly correlated to single cell events. In this paper direct cellular luciferase imaging using cell permeable luciferin substrates is applied for comparative analysis of cellular transduction events by two adenoviral vectors with different cell binding properties. Using digital imaging microscopy we show a more than ten-fold increase in transduction efficiency by Ad5LucRGD vectors versus AdCMVLuc vectors on human A549 cells.

Fine-needle aspiration cytology of cystic hypersecretory ductal carcinoma in situ of the breast: a case report.

Cystic hypersecretory intraductal carcinoma is an unusual, cystic form of intraductal breast carcinoma affecting middle-aged women. Cytopathologists have rarely encountered this lesion, with only 2 other cases having been previously reported (Colandrea et al., Arch Pathol Lab Med 1988:112:560-563; Kim et al., Acta Cytol 1997;41:892-896). In our cases, the cytologic findings of both air-dried, Diff-Quick-stained and ethanol-fixed, Papanicolaou-stained smears are presented. The cytologic hallmarks of this entity include the presence of a few scattered epithelial cells with bland nuclear morphology in a background of extensive, amorphous, pink-staining material. Cytomorphologically, the differential diagnosis includes other entities containing pink-staining material such as colloid carcinoma, mucocele-like lesion of the breast, and benign fibrocystic change.

Large cell calcifying Sertoli cell tumor of the testis: contrasting features of six malignant and six benign tumors and a review of the literature.

We report six malignant and six benign large cell calcifying Sertoli cell tumors of the testis and compare the features of malignant and benign cases based on these cases and those in the literature. All the tumors in this report consisted of sheets, nests, solid tubules, and cords of eosinophilic cells, with focal calcifications, as well as a substantial neutrophilic infiltrate in 11 of them. Analysis of our cases and those in the literature showed that the malignant tumors were unilateral and solitary and occurred at a mean age of 39 years (range 28-51 years), whereas the benign neoplasms were bilateral and multifocal in 28% of cases and occurred at a mean age of 17 years (range 2-38 years). Only one malignant tumor occurred in a patient with evidence of a genetic syndrome (Carney syndrome), whereas 36% of benign tumors had various genetic syndromes or endocrine abnormalities. Most of the tumors in the latter cases were bilateral and multifocal. There were strong associations of malignant behavior with size >4 cm, extratesticular growth, gross or microscopic necrosis, high-grade cytologic atypia, vascular space invasion, and mitotic rate greater than three mitoses per 10 high-power fields. All malignant cases exhibited at least two of these features, whereas all benign cases lacked any of them. The presence of any one of these features in a solitary large cell calcifying Sertoli cell tumor, especially in a patient >25 years of age, should be viewed as suspicious for malignant behavior, whereas the presence of two or more of these features indicates a strong probability of a malignant course. "Low" percentages (< or =35%) of tumor cells staining for proliferating cell nuclear antigen (PCNA) also may correlate with benign behavior, but some benign tumors have high PCNA values. Ki-67 values (MIB-1 antibody) did not correlate with biologic behavior, nor did immunostains for p53 protein.

Fine-needle aspiration biopsy of salivary duct carcinoma: report of five cases.

Salivary duct carcinoma is a high grade malignancy which histologically strongly resembles ductal carcinoma of the breast. The findings from five cases of histologically proven salivary duct carcinoma sampled by preoperative fine-needle aspiration (FNA) cytology are presented. Characteristic cytomorphologic features include cohesive clusters and flat sheets of epithelial cells which display a cribriform pattern with eccentrically located, hyperchromatic nuclei, abundant finely granular cytoplasm, and necrosis in the smear background.

Transcriptional control of the yeast acetyl-CoA synthetase gene, ACS1, by the positive regulators CAT8 and ADR1 and the pleiotropic repressor UME6.

The ACS1 gene, encoding one out of two acetyl-CoA synthetase isoenzymes of Saccharomyces cerevisiae, is strictly regulated at the transcriptional level by the carbon source of the medium. While ACS1 is poorly expressed in the presence of a high glucose concentration, a several hundred-fold derepression occurs with ethanol as the sole carbon source or under conditions of sugar limitation. The molecular mechanism responsible for the carbon source control of ACS1 turned out to be highly complex. A carbon source-responsive element (CSRE), previously identified upstream of gluconeogenic structural genes, and a binding site of the alcohol dehydrogenase regulator, Adr1p, together mediate about 80% of the derepressed gene activity. Binding of Adr1p synthesized by Escherichia coli to the ACS1 control region was shown by an electrophoretic mobility shift assay. In addition to these activating elements, two URS1 motifs confer negative control on the ACS1 promoter. The URS1 element was found to be a constitutive repression site, which is most effective from a downstream position with respect to an upstream activation site (UAS). In a mutant lacking the URS1-binding factor, Ume6p, ACS1 expression was partially glucose insensitive. Ume6p must counteract transcription factors that are constitutively active. Site-directed mutagenesis of Abf1p binding sites in the ACS1 promoter significantly reduced gene expression in the ume6 mutant, grown under repressing conditions. Thus, a functional balance of the pleiotropic positive factor Abf1p and the negative factor Ume6p is in part responsible for glucose repression of ACS1. The combined influence of the regulated UAS elements, CSRE and Adr1p binding site, mediates a strong increase in ACS1 expression under derepressing conditions.

Carbon source-dependent regulation of the acetyl-coenzyme A synthetase-encoding gene ACS1 from Saccharomyces cerevisiae.

The yeast ACS1 gene, encoding acetyl-coenzyme A synthetase (ACS), was cloned using colony hybridization and a facA probe from Aspergillus nidulans. The complete sequence of 1.5 kb of the ACS1 upstream region was determined. Northern hybridization revealed a strong depression of ACS1 transcripts in a strain grown on the nonfermentable carbon sources, acetate or ethanol. In contrast to a previous report, delta acs1 null mutants did not exhibit a growth defect on acetate medium. Indeed, enzyme assays showed the presence of an additional constitutively expressed ACS activity in delta acs1 mutants. The carbon source-dependent expression was further investigated by the use of an ACS1::lacZ fusion gene, showing complete repression on easily fermentable sugars such as glucose, maltose, sucrose or galactose. Binding sites for the yeast general regulatory factors, Abf1p and Reb1p, together with a sequence reminiscent of the recently identified carbon source-responsive element (CSRE), could be detected in the ACS1 upstream region, presumably mediating the observed regulatory phenotype of this ACS isoenzyme.

Cystic neoplasms of the pancreas.

Cystic neoplasms of the pancreas are interesting, but rare. We reviewed the Indiana University experience with these tumors over a 15-year period to study preoperative evaluation and long-term outcome. Twenty-one patients (18 females and three males, mean age 59 years) were treated between 1977 and 1992. The lesions included mucinous cystic neoplasm-benign (6), mucinous cystic neoplasm-malignant (6), serous cystadenoma (5), ductal adenocarcinoma with cystic degeneration (2), papillary cystic neoplasm (1), and intra-ductal mucin hypersecreting neoplasm (1). The most common symptoms were abdominal pain, back pain, and weight loss. All eight patients with malignant tumors had symptoms; however, only seven of 13 patients with benign lesions had symptoms (P = 0.046, Fisher exact test). Patients were evaluated with computed tomography of the abdomen (20), endoscopic retrograde cholangiopancreatography (12), ultrasound (5), fine needle aspiration (4), and other studies (6). Six lesions were found incidentally. A correct preoperative diagnosis was made in only two cases. Operations performed included 14 distal pancreatectomies, five pancreaticoduodenectomies, and one total pancreatectomy. Fifteen of 21 patients are alive and well, with follow-up ranging from 4 months to 16 years. Five deaths occurred in patients with malignant mucinous cystic neoplasms, while only one death occurred in the patients with benign cystic neoplasms. Although computed tomography and other diagnostic modalities can identify cystic neoplasms of the pancreas, it is often difficult to make a definitive diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Endometriosis of the small intestine presenting as a protein-losing enteropathy.

A 46-yr-old multiparous cachetic woman presented with severe hypoalbuminemia in the absence of liver disease, proteinuria, and/or protracted starvation. The clinical presentation and work-up was indicative of protein-losing enteropathy. She developed an acute partial small bowel obstruction, and a presumptive diagnosis of lymphoma of the small intestine was entertained. Surgical resection of the terminal ileum revealed transmural involvement of the bowel by endometriosis. Her postoperative recovery was uneventful, with return of her serum albumin levels to normal.