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Notes: In vitro assays have demonstrated that peptides derived from the recently–identified proSAAS precursor inhibit prohormone convertase 1 (PC1) suggesting that this novel peptide may function as an endogenous inhibitor of PC1. To further understand the role of proSAAS in vivo, we have investigated the expression of proSAAS mRNA and processing of proSAAS during pre- and early postnatal rodent development. In situ hybridization showed that, by embryonic day 12.5 (e12.5) in the rat, proSAAS mRNA was present in essentially all differentiating neurons in the mantle layer of the myelencephalon, metencephalon, diencephalon, spinal cord and several sympathetic ganglia. During later stages of prenatal development, widespread proSAAS expression continues in post-mitotic neurons of both the CNS and PNS and begins in endocrine cells of the anterior and intermediate pituitary. Although proSAAS expression overlaps with PC1 in several regions, its overall expression pattern is significantly more extensive, suggesting that proSAAS may be multifunctional during development. Processed forms of proSAAS are present by at least mid-gestation with marked accumulation of two C-terminal forms, comprising the PC1 inhibitory fragment of proSAAS.

Notes: Background: Prolonged QRS duration (QRSd) is a useful index for the management of patients with congestive heart failure (CHF). QRSd is affected by changes in the ECG voltage (ECGV) in the context of development and amelioration of peripheral edema (PERE), independent of underlying pathology. Nowadays, physicians accept QRSd measured by computer techniques. The latter offers the possibility of testing the hypothesis that artificial alteration of the ECGV, simulating effects of PERE, could lead to changes in the QRSd. Methods: To this end, voltage was attenuated by 25%, 50%, and 75% in 100 digital ECGs recorded from normal subjects and in 20 patients with complete left bundle branch block (LBBB), by merely increasing the calibration strength by 4/3, 2, and 4, respectively, and by using the same data. Results: All ECGs were analyzed by the same computer program and this led to a reduction of global QRSd by 2.3 ± 2.9%, 5.7 ± 4.0%, and 11.9 ± 6.2%, respectively, in the normal subjects, and 1.6 ± 1.4%, 3.4 ± 1.7%, and 8.2 ± 3.6%, respectively, in the patients with LBBB. Correlation of the percent change in the global QRSd and the percent change in ECGV was good with an r = 0.65, and P = 0.00005 in the normal subjects, and an r = 0.74 and P = 0.00005 in the patients with LBBB. Conclusions: Apparent shortening in QRSd as a function of ECGV attenuation due to PERE could have implications in the follow-up of patients with CHF, and their selection for implantable cardioverter/defibrillators, or cardiac resynchronization therapy.

Notes: Associations have been described among weight, amplitude of QRS complexes, and QRS duration (QRSd) in patients with anasarca (AN), and changes in the amplitude of the QRS complexes, QRSd, and QTc after hemodialysis (HD) and in patients with heart failure with associated peripheral edema congestive heart failure. The objective of this study was to evaluate the hypothesis that changes in QTc in patients with AN and after HD are at least partially apparent, due to changing edematous states, and not totally due to altered electrophysiology. QTc was measured in patients with AN on admission, at peak weight (N = 28), and at their subsequent lowest weight (N = 12), in 28 control patients without change in weight during hospitalization, and in one patient before and after 26 HD sessions. In the patients with AN, the QTc was 451 ± 36 ms on admission and dropped to 423 ± 46 ms at peak weight (P = 0.005). QTc was 421 ± 44 ms at peak weight and raised to 434 ± 30 at subsequent lowest weight (P = 0.32). In the controls, QTc on admission and at discharge were 435 ± 34 and 428 ± 23 ms, correspondingly (P = 0.18). QTc increased from 472 ± 18 ms before to 489 ± 36 ms after HD (P = 0.017). Alterations in QTc in AN, or HD suggest that the changes in the QTc may be partially only apparent, and due to the electrocardiogram machine-based measurement of the attenuated/augmented QRST complexes resulting from fluid shifts.

Notes: Because of limited tolerance to cold, most Florida manatees survive cold winter periods by aggregating at warm-water discharges from power plants and natural springs in central and northern Florida. Many power plants used by manatees may soon be retired. When this occurs, some people assume manatees will move to warmer areas in southern Florida; others fear they will stay near retired plants and sustain high levels of cold-related deaths causing a decline in abundance. To assess these possibilities, we examine warm-water habitats, population structure and movement, cold-related deaths, and information on possible historical manatee distribution. Winter water temperatures even in southernmost Florida periodically fall below manatee tolerance levels. To survive such periods, manatees use two types of warm-water refuges: warm-water discharges, and passive thermal basins that cool slowly, thereby temporarily retaining warm temperatures. During the coldest periods, perhaps 60% of all manatees use 10 power plants and 15% use four natural springs; most others use thermal basins in southern Florida. Site fidelity to these refuges appears to be the principal factor segregating manatees into at least four subpopulations. Since 1986, rates of cold-related deaths in southernmost Florida (10.0%) have exceeded those in areas with natural springs in central and northern Florida (8.8%). Our findings suggest that warm-water springs in northern Florida offer better winter habitat than thermal basins in southern Florida and are better able to support large numbers of manatees. Although evidence is scant, we suggest that manatees historically overwintered principally at northern springs, but that Pre-Columbian and European hunting restricted their winter range to southernmost Florida by the early 1900s. We also suggest that southernmost Florida may not be able to sustain a large influx of displaced of manatees in the absence of power plants, and that warm-water springs in northern Florida should be considered the most important source of natural warm-water habitat.

Notes: Deoxyhypusine synthase (DHS; EC 2.5.1.46) mediates the first of two enzymatic reactions that convert inactive eukaryotic translation initiation factor-5A (eIF-5A) to an activated form, thought to facilitate translation. A full-length cDNA clone encoding canola (Brassica napus cv. Westar) DHS was isolated from a cDNA-expression library prepared from senescing leaves. Transgenic canola lines with suppressed DHS expression were obtained by introducing a transgene expressing antisense 3′-UTR canola DHS cDNA under the regulation of the constitutive cauliflower mosaic virus 35S (CaMV-35S) promoter. Transformed seed was obtained by vacuum infiltration of canola inflorescences using the protocol developed for Arabidopsis with modifications. The resultant transgenic plants had reduced levels of leaf DHS protein and exhibited delayed natural leaf senescence. Suppression of DHS also increased leaf size by 1.5- to two-fold and resulted in increases in seed yield of up to 65%. Moreover, the enhanced performance of transgenic plants reflected increased tolerance to chronic sublethal stress. When wild-type and transgenic plants were grown in 6-inch pots, the increase in seed yield accruing from suppression of DHS was approximately 4.5-fold greater than when the plants were grown in 12-inch pots. Thus, suppression of DHS appears to ameliorate the effects of sublethal stress engendered by growth in small containers.

Notes: Background:  Children with Kawasaki's syndrome (KS), also known as Kawasaki's disease or ‘mucocutaneous lymph node syndrome’, have approximately 20–25% incidence of developing coronary artery aneurysms (CAA), stenosis or obliteration if not appropriately diagnosed and treated. In addition some children have myocarditis, pericardial effusions and/or cardiac arrhythmias during the acute phase of KS. Even with current treatment protocols, 2–4% will still be at risk of coronary artery pathology and the long-term implications regarding future coronary artery disease are unknown. Many of these children present for surgical or diagnostic procedures requiring general anesthesia or deep sedation. Only sporadic case reports have been published on the anesthetic experiences of such patients.Methods:  With Institutional Review approval, we reviewed the medical records of all children with discharge diagnosis of KS from 1985 to 2000 for those receiving general anesthesia or deep sedation. Data abstracted from the medical records included information on any surgical procedures performed any time after onset of KS symptoms, type of anesthetic, perioperative monitoring and presence or absence of operative or perioperative complications.Results:  A total of 178 children with KS were identified of whom 47 (26.4%) received either general anesthesia (34) or deep sedation (13). There were no deaths; one child developed congestive heart failure in the immediate postoperative period associated with KS myocarditis. Five (15%) of those having general anesthesia initially were either not diagnosed as having KS or had no preoperative cardiac evaluations. None of the children having general anesthesia had ST segment analysis, invasive monitoring or troponin measurements perioperatively.Conclusions:  The high incidence of serious myocardial complications attributable to KS reported in the pediatric literature is rarely noted in the anesthesia literature. We feel there is a potential for more serious perioperative complications among KS children, although we can only speculate why complications are not more frequently encountered. Anesthetists involved in pediatric services are encouraged to consider KS in their diagnosis of children presenting with febrile illnesses with rashes and to consider the possibility of KS myocardial compromise if they encounter unexpected deterioration perioperatively. Preoperative ultrasound examination and perioperative monitoring (e.g. ST segment analysis and troponin measurements) for myocardial compromise are encouraged if KS is suspected.

Notes: We propose a theory of party competition (two parties, single-issue) where citizens acquire party membership by contributing money to a party, and where a member's influence on the policy taken by her party is proportional to her campaign contribution. The polity consists of informed and uninformed voters: only informed voters join parties, and the party campaign chest, the sum of its received contributions, is used to reach uninformed voters through advertising. A party is a cooperative organization of its members. Parties compete with each other strategically with respect to policy choice and advertising. We propose a definition of political equilibrium, in which party membership, citizen contributions, and parties' policies are simultaneously determined, for each of four financing institutions, running the gamut between a purely private, unconstrained system, to a public system in which all citizens have equal financial input. Equilibria under these institutions are computed by simulation for an example. The representation and welfare properties of these four institutions are compared from these simulations.

Notes: Umbilical cord blood transplantation (UCBT) is an expanding practice for both pediatric and adult patients. Rapid availability, low risk of infectious disease transmission, lower risk of graft-versus-host disease, and lack of risk for the donor makes UCB an attractive alternative source of hematopoietic stem cells for transplantation. We review the state of the art of pediatric and adult UCBT and important aspects of UCB banking. Current strategies to improve clinical results and expand access to UCBT to a larger number of adult patients are discussed. New approaches to enhance hematopoietic recovery by the use of accessory cells or direct intra-bone marrow injection are also reviewed.

Notes: The neonicotinoids, the newest major class of insecticides, have outstanding potency and systemic action for crop protection against piercing-sucking pests, and they are highly effective for flea control on cats and dogs. Their common names are acetamiprid, clothianidin, dinotefuran, imidacloprid, nitenpyram, thiacloprid, and thiamethoxam. They generally have low toxicity to mammals (acute and chronic), birds, and fish. Biotransformations involve some activation reactions but largely detoxification mechanisms. In contrast to nicotine, epibatidine, and other ammonium or iminium nicotinoids, which are mostly protonated at physiological pH, the neonicotinoids are not protonated and have an electronegative nitro or cyano pharmacophore. Agonist recognition by the nicotinic receptor involves cation-?? interaction for nicotinoids in mammals and possibly a cationic subsite for interaction with the nitro or cyano substituent of neonicotinoids in insects. The low affinity of neonicotinoids for vertebrate relative to insect nicotinic receptors is a major factor in their favorable toxicological profile.