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A rudimentary understanding of age, growth, and life-span is lacking for many non-game fishes. Growth characteristics of the central mudminnow ( Umbra limi) have not yet been accurately described using reliable hard part analysis. The utility of scales and otoliths as ageing structures and quantified growth was examined in one lake and one stream population of central mudminnow. Scales were found to be of no utility in determining age due to inconsistent formation of yearly annuli and a high incidence of regenerated scales, while otoliths were easily extracted and considered to be an accurate ageing structure. Ages determined from scales were low compared to those from otoliths, and the difference in age interpreted from the two structures increased with fish age. A power function was fitted to describe the length-weight relationship for this species ( a = 0.0069, b = 3.175). Von Bertalanffy growth parameters were estimated and compared for each population (Lake: L∞ = 114.20 mm, K = 0.30, t0 = −0.93; Stream: L∞ = 77.59 mm, K = 0.63, t0 = −0.76). The lake population showed greater size at age compared to the stream population, especially at older ages, and achieved a larger maximum size. Growth rate was also greater in the lake population (Lake: 1.74; Stream: 1.09 g year−1). Females were larger at age than males in both populations, however all individuals greater than age 3 were males. This work represents the first successful account of central mudminnow growth using hard part analysis. [ABSTRACT FROM AUTHOR]

The earliest evidence for animal life comes from the fossil record of 24-isopropylcholestane, a sterane found in Cryogenian deposits, and whose precursors are found in modern demosponges, but not choanoflagellates, calcareans, hexactinellids, or eumetazoans. However, many modern demosponges are also characterized by the presence of siliceous spicules, and there are no convincing demosponge spicules in strata older than the Cambrian. This temporal disparity highlights a problem with our understanding of the Precambrian fossil record – either these supposed demosponge-specific biomarkers were derived from the sterols of some other organism and are simply retained in modern demosponges, or spicules do not primitively characterize crown-group demosponges. Resolving this issue requires resolving the phylogenetic placement of another group of sponges, the hexactinellids, which not only make a spicule thought to be homologous to the spicules of demosponges, but also make their first appearance near the Precambrian/Cambrian boundary. Using two independent analytical approaches and data sets – traditional molecular phylogenetic analyses and the presence or absence of specific microRNA genes – we show that demosponges are monophyletic, and that hexactinellids are their sister group (together forming the Silicea). Thus, spicules must have evolved before the last common ancestor of all living siliceans, suggesting the presence of a significant gap in the silicean spicule fossil record. Molecular divergence estimates date the origin of this last common ancestor well within the Cryogenian, consistent with the biomarker record, and strongly suggests that siliceous spicules were present during the Precambrian but were not preserved. [ABSTRACT FROM AUTHOR]

NBI-6024 is an altered peptide ligand (APL) corresponding to the 9–23 amino acid region of the insulin B chain (B(9−23)), an epitope recognized by inflammatory interferon-γ-producing T helper (Th)1 lymphocytes in type 1 diabetic patients. Immunomodulatory effects of NBI-6024 administration in recent-onset diabetic patients in a phase I clinical trial (NBI-6024-0003) were measured in peripheral blood mononuclear cells using the enzyme-linked immunosorbent spot assay. Analysis of the mean magnitude of cytokine responses to B(9−23) and NBI-6024 for each cohort showed significant increases in interleukin-5 responses (a Th2 regulatory phenotype) in cohorts that received APL relative to those receiving placebo. A responder analysis showed that Th1 responses to B(9−23) and NBI-6024 were observed almost exclusively in the placebo-treated diabetic population but not in nondiabetic control subjects and that APL administration (five biweekly subcutaneous injections) significantly and dose-dependently reduced the percentage of patients with these Th1 responses. The results of this phase I clinical study strongly suggest that NBI-6024 treatment shifted the Th1 pathogenic responses in recent-onset type 1 diabetic patients to a protective Th2 regulatory phenotype. The significance of these findings on the clinical outcome of disease is currently under investigation in a phase II multidose study. [ABSTRACT FROM AUTHOR]

This discussion reviews evidence supporting the hypothesis that within intact chloroplasts in vivo, molecular O2 may serve as an alternative Hill oxidant (electron acceptor) on the reducing side of Photosystem I. Depending upon the availability of Hill oxidants such as NADP+ and NO2−, there is the potential within intact plastids in vivo, for photolytically derived reducing equivalents to reduce O2 to O2− and H2O2 (the Mehler reaction). In chloroplasts of healthy tissues, the products of photosynthetic O2 reduction O2− and H2O2) are rapidly removed by superoxide dismutase (EC 1.15.1.1) and L‐ascorbate peroxidase (EC 1.11.1.11) to prevent toxicity. The presence of these two enzymes within chloroplasts in vivo reflects the potential for linear (non‐cyclic) photosynthetic electron transport systems to draw upon molecular O2 as a terminal oxidant. In the intact plastid, O2 may act as an electron acceptor in the place of any other physiological Hill oxidant, e.g., NADP+, NO2−, and, presumably, oxidized thioredoxin. Under aerobic, physiological conditions, photo reduced ferredoxin (Fdred), and/or reduced flavoprotein enzymes, e.g., ferredoxin:NADP+ oxidoreductase (EC 1.18.1.2), can donate electrons to O2; this reductive reaction appears to be non‐enzymatic, but it is rapid. Stated from another viewpoint, O2 may serve as a Hill oxidant to support some linear electron flow when reductant supplies are in excess of reductant demands. For example, there are nitrogen assimilatory sites in the chloroplast, i.e., ferredoxin‐nitrite reductase (NiR; EC 1.7.7.1) and glutamate synthase (ferredoxin) (GOGAT; EC 1.4.7.1), to which Fdred is allocated as reductant. Because NADH:nitrate reductase (NR; EC 1.6.6.1) is the rate limiting step of nitrogen assimilation, and, because NiR and GOGAT activities are in excess of NR activities by a factor of 2 or more, then an excess of unreacted Fdred could accumulate. Alternatively, the allocated Fdred would reduce the excess NiR and GOGAT sites, but the excess of reduced enzymes would not have substrates (e.g., NO2−, glutamine, and α‐ketoglutarate) with which to react. Therefore, if ‘excess’ NiR and GOGAT binding sites were not employed, the available excess Fdred, and/or the reduced NiR and GOGAT proteins, would be susceptible to oxidation by O2. The resulting O2 photoreduction could account for nearly all of the observed in vivo Mehler type reactions. In vivo, apparent foliar O2 photoreduction occurs simultaneously with maximal CO2 photoassimilation, and, in high light, average rates have been determined by direct measurement to range from 10 to 40 μmol O2 consumed (mg Chl)−1 h−1. Therefore O2 reduction would support a low rate of linear (non‐cyclic) electron flow which, in turn, could maintain a low, but significant rate of ATP production. However, there is not total agreement among researchers that the physiological role of O2 is that of serving as an alternative Hill oxidant in order to recycle unutilized Fdred or other photoreduced proteins. Also, there continues to be considerable controversy on whether or not O2 reduction supports significant photosynthetic phosphorylation. The total process of O2 photoreduction, and its physiological role(s), requires much more study before absolute functions can be assigned to O2 terminated, linear electron transport. [ABSTRACT FROM AUTHOR]

- A 4-week randomised, double-blind, cross-over study is described which compared the effects of a combination of emepronium bromide and flavoxate hydrochloride with placebo on incontinence and cystometrogram findings in 20 female patients aged 59 to 88 years. All patients initially had detrusor instability demonstrated on cystometrography: 14 patients completed the study; on placebo 10 still had unstable bladders and on active drugs seven were unstable. The number of wettings over a 48-h period before the study commenced and at the end of each course of tablets showed no significant differences; also the patients' opinions about the effect on their incontinence indicated that the majority had the same opinion of each course. Active drugs significantly increased residual urine but did not significantly alter the values obtained for maximum cystometric capacity or effective cystometric capacity (the latter volume being maximum cystometric capacity minus the residual urine). No correlation was found, on either course of treatment, between the change to detrusor stability and the amount of improvement in incontinence. Some side effects are described. Despite evidence of a pharmacological effect on the bladder and patients' opinions tending to favour the active combination, nonetheless the main results of this small study do not suggest that the combination of emepronium bromide and flavoxate hydrochloride is an effective treatment of urinary incontinence associated with detrusor instability in elderly women. [ABSTRACT FROM AUTHOR]

A renal transplant recipient developed acute renal transplant vein thrombosis following surgery for a total hip replacement. As an alternative to standard surgical therapy, the patient was treated with selective intravenous low-dose infusion of streptokinase at doses of 5,000-20,000 units/h. The infusion was continued for 120 h with constant monitoring of PT, PTT, and fibrinogen levels. Therapy resulted in excellent preservation of renal function without complications. Low-dose selective infusion of streptokinase should be considered a potential alternative therapy for acute transplant renal vein thrombosis. [ABSTRACT FROM AUTHOR]

A randomized, double-blind study of valaciclovir for suppression of recurrent genital herpes was conducted among 1479 immunocompetent patients. Patients were randomized to receive valaciclovir (250 mg, 500 mg, or 1 g once daily, or 250 mg twice daily), acyclovir (400 mg twice daily), or placebo, for 1 year. All valaciclovir dosages were significantly more effective than placebo at preventing or delaying recurrences (P < .0001). There was a dose-response relationship (P < .0001) across the once-daily valaciclovir regimens. Twice-daily valaciclovir and acyclovir were similar in effectiveness. Subgroup analysis showed that patients with a history of <10 recurrences per year were effectively managed with 500 mg of valaciclovir once daily. One gram of valaciclovir once daily, 250 mg of valaciclovir twice daily, or 400 mg of acyclovir twice daily were more effective in patients with ⩾10 recurrences per year. Safety profiles of all treatments were comparable. Thus, valaciclovir is highly effective and well tolerated for suppression of recurrent genital herpes. Once-daily regimens offer a useful option for patients who require suppressive therapy for management of genital herpes. [ABSTRACT FROM PUBLISHER]