Posterodorsal amygdaloid lesions in rats: long-term effects on body weight

Bilateral lesions in the most posterodorsal aspects of the amygdala in female rats resulted in immediate and dramatic weight gains on a standard lab chow diet. The rate of weight gain returned to normal by Day 20, but the difference in body weight between animals with amygdaloid lesions and those with sham lesions was maintained for the duration of the study (60 days). Because rats with posterodorsal amygdaloid lesions have also been found to be hyperinsulinemic, it is hypothesized that the lesions result in a similar, though smaller, version of the syndrome that follows lesions of the ventromedial hypothalamus.     

Z/I and A-band lattice spacings in frog skeletal muscle: effects of contraction and osmolarity

A-band and Z-line/I-band lattice spacings were measured by small-angle X-ray diffraction from relaxed and isometrically-contracting whole frog sartorius muscles with lattice spacings reduced or swollen by changing the osmolarity of the bathing solution. A-band spacing increased by approximately 3% upon isometric contraction at reduced lattice spacings (245-356 mOsm) and decreased by approximately 1% at swollen spacings (172 mOsm), similarly to the behaviour of skinned muscles upon changing from the relaxed state to rigor. The Z/I lattice underwent a significant lattice expansion (3-8%) upon isometric contraction at all osmolarities, in qualitative agreement (but quantitative disagreement) with results from electron microscopy on mammalian skeletal muscle. Lattice areas calculated for the Z/I and A-band lattices indicate a barrel-shaped sarcomere in the resting state, which may provide a partial explanation for how longitudinal forces produced in the A-band can produce a radial expansive force in the Z-line during contraction. The radial component of cross-bridge stiffness was calculated from the A-band data for contracting muscle, using a lattice stability model incorporating structural, osmotic and electrostatic forces. The calculations gave a radial cross-bridge stiffness during contraction of about 9 x 10(5) N m-2, and outward radial force per thick filament in normal Ringer's solution of 6 x 10(-9) N, corresponding to a radial force per cross-bridge of 10(-11) N.     

Novel expression and regulation of gastrin gene in human ovarian cancer cell line, SW626

Gastrin-secreting tumors have been identified in ectopic locations including the ovary; the mechanisms regulating gastrin gene expression, its distribution, and signaling pathways in these ectopic tissues are not known. The purpose of our present study was to determine: (1) whether the gastrin gene and peptide could be detected in ovarian cancer cell lines, (2) if functional gastrin releasing peptide receptors (GRP-R) are present, and (3) whether gastrin gene expression is altered by GRP. Five ovarian cancer cell lines (SW626, OVCA 420, OVCA 429, OVCA 432, and OVCA 433) were analyzed. We identified gastrin gene and peptide expression in the SW626 cell line but not in the OVCA lines. SW626 cells express a functional GRP-R that is correctly coupled to the Ca2+ signaling pathway. Treatment of SW626 cells with bombesin, the amphibian equivalent of GRP, inhibited expression of the gastrin gene in a time- and dose-dependent fashion. The SW626 ovarian cancer cell line will provide a useful model to further define regulation and expression of both the gastrin gene and peptide in ectopic (nongastrointestinal) tissues.     

County funding of mental health services in a rural state

A case of lobar torsion after lung surgery is reported here. She developed a right middle lobar torsion diagnosed by postoperative bronchial fiberscopy, suggesting incomplete obstruction of the intermedial bronchus. Re-operation was performed successfully either by fixing the right lower lobe to both the middle lobe and the thoracic wall. Careful postoperative observation with chest radiography, bronchial fiberscopy, are important for precise diagnosis of and therapy for lobar torsion following pulmonary lobectomy.     

Performance analysis of the forgetting factor RLS algorithm

An analysis is given of the performance of the standard forgetting factor recursive least squares (RLS) algorithm when used for tracking time-varying linear regression models. Three basic results are obtained: (1) the ‘P-matrix’ in the algorithm remains bounded if and only if the (time-varying) covariance matrix of the regressors is uniformly non-singular; (2) if so, the parameter tracking error covariance matrix is of the order O(μ + γ²/μ), where μ = 1 - λ, λ is the forgetting factor and γ is a quantity reflecting the speed of the parameter variations; (3) this covariance matrix can be arbitrarily well approximated (for small enough μ) by an expression that is easy to compute.     

Dynamics and organization of MAP kinase signal pathways

In the budding yeast, Saccharomyces cerevisiae, four separate but structurally related mitogen-activated protein kinase (MAPK) activation pathways are known. The best understood of these regulates mating. Pheromone binding to receptor informs cells of the proximity of a mating partner and induces differentiation to a mating competent state. The MAPK activation cascade mediating this signal is made up of Ste11 (a MEK kinase [MEKK]), Ste7 (a MAPK/ERK kinase [MEK]), and the redundant MAPK-related Fus3 and Kss1 enzymes. Another MAPK activation pathway is important for cell integrity and regulates cell wall construction. This cascade consists of Bck1 (a MEKK), the redundant Mkk1 and Mkk2 enzymes (MEKs), and Mpk1 (a MAPK). We exploited these two pathways to learn about the coordination and signal transmission fidelity of MAPK activation cascades. Two lines of evidence suggest that the activities of the mating and cell integrity pathways are coordinated during mating differentiation. First, cells deficient in Mpk1 are susceptible to lysis when they make a mating projection in response to pheromone. Second, Mpk1 activation during pheromone induction coincides with projection formation. The mechanism underlying this coordination is still unknown to us. Our working model is that projection formation generates a mobile second messenger for activation of the cell integrity pathway. Analysis of a STE7 mutation gave us some unanticipated but important insights into parameters important for fidelity of signal transmission. The Ste7 variant has a serine to proline substitution at position 368. Ste7-P368 has higher basal activity than the wild-type enzyme but still requires Ste11 for its function. Additionally, the proline substitution enables the variant to transmit the signal from mammalian Raf expressed in yeast. This novel activity suggests that Ste7-P368 is inherently more permissive than Ste7 in its interactions with MEKKs. Yet, Ste7-P368 cross function in the cell integrity pathway occurs only when it is highly overproduced or when Ste5 is missing. This behavior suggests that Ste5, which has been proposed to be a tether for the kinases in the mating pathway, contributes to Ste7 specificity and fidelity of signal transmission.     

Reaction products of ammonium nitrate phosphate fertilizers of varying water-soluble phosphorus content in different Indian soils

Studies were undertaken on the isolation and identification of reaction products of ammonium nitrate phosphate (ANP) fertilizers containing 30, 50 and 70 per cent water-soluble phosphorus (WSP) of total phosphorus in representative soils of the vertisol, oxisol, alfisol, entisol, mollisol and aridisol groups of India. ANP fertilizers were applied in solid form to soil, and reaction products formed at and around the site of ANP fertilizer placement were identified after six weeks incubation in moist soils by X-ray diffraction technique. DCPD (dicalcium phosphate dihydrate- CaHPO₄ · 2H₂O) was the major reaction product of ANP fertilizers containing 30 and 50 per cent WSP in vertisol, entisol, aridisol, mollisol, oxisol and alfisol, and of ANP containing 70 per cent WSP in vertisol, entisol, alfisol, aridisol and mollisol. DCP (dicalcium phosphate-CaHPO₄) was detected with ANP of 30 and 50 per cent WSP in the vertisol, alfisol, entisol, mollisol and aridisol groups of soils. In addition to DCPD, FePO₄ · 2H₂O (metastrengite) and AlPO₄ · 2H₂ O-monoclinic (metavariscite) were formed in alfisol and oxisol soils with ANP of 30 and 50 per cent WSP. FePO₄ · 2H₂O and AlPO₄ · 2H₂O (metavariscite) were identified in alfisol and oxisol soils while AlPO₄ · 2H₂O-orthorhombic (variscite) was formed in alfisol soils with ANP of 70 per cent WSP.     

Interpretation time of serial chest CT examinations with stacked-metaphor workstation versus film alternator

PURPOSE: Interpretation time of serial staging chest CT cases, which each contained current and previous examinations, with a simple prototype workstation called filmstack was experimentally compared with interpretation time with a film alternator. MATERIALS AND METHODS: The filmstack displayed a "stack" of sections for each examination; user controls allowed rapid selection of preset attenuation windows and both synchronized and unsynchronized scrolling. Eight radiologists were timed as they used the filmstack and the film alternator to interpret four ergonomically complex serial CT cases. RESULTS: All reports dictated on the basis of findings with filmstack and film were of acceptable clinical accuracy. The time to examine a case with filmstack was significantly faster than the time with film, including the time to load and unload the alternator (99% confidence [P = .01]). There was no statistically significant difference in interpretation time between filmstack and prehung film. CONCLUSION: Use of a low-cost stacked CT workstation with a single 1,024 x 1,024 monitor is an effective means of interpreting cases that require comparison of multiple CT examinations.