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Notes: In a pilot study, ranitidine bismuth citrate (RBC; Pylorid, Tritec) in coprescription with clarithromycin achieved a Helicobacter pylori eradication rate (based on 13C urea breath test alone) of 83%. The aim of the current study was to validate this finding by using three diagnostic tests and a larger group of H. pylori–positive patients with active duodenal ulcer.〈section xml:id="abs1-2"〉〈title type="main"〉Methods.In a blinded study, 95 patients were given either 4 weeks of treatment with RBC, 400 mg bid, alone (RBC400, n = 31) or RBC, 400 mg bid or 800 mg bid, in coprescription with clarithromycin, 250 mg qid for 14 days, followed by 14 days of RBC, 400 mg bid, alone (RBC400+CLAR and RBC800+CLAR, respectively; n = 32 for each). Rates of ulcer healing at week 4 and of H. pylori eradication (assessed by antral and corpus urease tests and histology and by 13C urea breath test) at week 8 were compared, together with the incidence of adverse events.〈section xml:id="abs1-3"〉〈title type="main"〉Results.All three regimens were effective at duodenal ulcer healing and were tolerated well. The coprescription regimens gave significantly higher observed H. pylori eradication rates (82% and 74% for RBC400+ CLAR and RBC800+CLAR) compared with RBC400 (0%;p 〈 .001).〈section xml:id="abs1-4"〉〈title type="main"〉Conclusions.RBC in dual therapy with clarithromycin provides excellent H. pylori eradication therapy and is an effective duodenal ulcer healing drug.

Notes: To elucidate the role for transforming growth factor-β isoforms (β1, -β2, and -β3) in wound repair, we used isoform-specific antibodies to detect the spatial and temporal expression of the latent and mature/active transforming growth factor-β isoforms by immunohistochemical localization through 21 days after excisional and incisional wounding of ovine skin. Although incisional and excisional wounds showed similar patterns of transforming growth factor-β immunoreactivity, we found a differential temporal and spatial expression of the latent and mature transforming growth factor-β isoforms throughout wound repair. Specifically, 1 day after wounding, there was a marked increase in transforming growth factor-β isoforms in the epithelium adjacent to the wound, epidermal appendages, and the cells and matrix of the granulation tissue. At this time, transforming growth factor-β3 isoform was the most abundant. Most notably, the epidermis adjacent to the wound was intensely immunoreactive for all transforming growth factor-β isoforms 1 day after injury. However, the migrating epithelium, derived from both the hair follicles and the wound margins, was completely devoid of immunoreactive transforming growth factor-β until reepithelialization was complete. Within the inflammatory exudate, there was a distinct band of leukocytes that was immunoreactive for transforming growth factor-β2 and -β3 1 day after injury and 1 day later for transforming growth factor-β1. Although transforming growth factor-β1 and -β2, latent transforming growth factor-β2, transforming growth factor-β3, and latent transforming growth factor-β3 immunostaining was present in the numerous fibroblasts and other dermal cells, latent transforming growth factor-β1 was only associated with the extracellular matrix. In general, immunoreactivity remained high until day 7 after wounding and slowly subsided over time. However, by day 21, immunostaining had not returned to normal and the original wound was replete with immunoreactive fibroblasts and a dense, immunostained extracellular matrix. Thus, although the dynamic presence of transforming growth factor-β isoforms exemplifies its positive role in the wound repair process, its persistence together with its known potent effects on matrix accumulation, supports its role in scar formation.

Notes: Insulin-like growth factor-I is a polypeptide hormone structurally related to insulin. It is a potent mitogen that promotes growth and differentiation in many tissues. A role for insulin-like growth factor-I in wound healing is suggested by its rapid rise in levels and increased insulin-like growth factor-I messenger RNA expression in tissue after wounding. We designed our study to characterize possible changes in insulin-like growth factor-I receptor binding during wound healing. Surgical wounds created on the abdominal skin of anesthetized New Zealand White rabbits were either left open or closed primarily. Size- and weight-matched specimens were harvested at wounding time (day 0), and at 1, 4, 7, 38, and 50 days after wounding. Preliminary experiments showed that the greatest difference in specific binding occurred between day 0 and day 7. 125I-insulin-like growth factor-I binding studies were performed on frozen tissue specimens and autoradiography was performed and analyzed by computerized densitometry. Scatchard analysis of the binding data showed a single class of insulin-like growth factor-I binding sites whose affinity that is, binding constant (Kd = 0.6 × 10−9) did not change significantly over time; in contrast there was a threefold increase in the number of receptors per milligram tissue in day 7 wound tissue versus normal skin harvested at day 0 (17.3 ± 2.6 × 1010 versus 4.7 ± 2.5 × 1010, respectively, p 〈 0.05). Binding inhibition experiments showed that 125I-insulin-like growth factor-I binding was most specific to insulin-like growth factor-I with insulin-like growth factor-I 〉 insulin-like growth factor-II 〉 insulin. This increase in binding was due to upregulation of insulin-like growth factor-I receptors rather than increased levels of insulin-like growth factor-I binding protein as less than 20% of the threefold increase in binding at day 7 could be attributed to insulin-like growth factor-I binding protein in membrane-free extracts. The presence of specific, high-affinity insulin-like growth factor-I receptors in the skin and their upregulation at day 7 after wounding suggest that insulin-like growth factor-I plays an important role during wound healing.

Notes: Objective To determine the efficacy of a 100 μg twice weekly dose of Estraderm TTS compared with a 200 μg dose in the treatment of severe PMS, and to determine the overall acceptability of the treatment. To determine the serum oestradiol levels produced by the two doses of Estraderm and to discover whether the lower dose suppresses ovulation.Design Main: randomised, prospective, comparative study. Subsidiary: cross-sectional and prospective.Setting Premenstrual syndrome clinic in teaching hospital.Subjects Women with severe PMS confirmed by prospective daily symptom recording.Interventions Estraderm TTS® at a dose of either 100 or 200 μg twice weekly continuously with either dydrogesterone 10 mg or medroxyprogesterone acetate 5 mg, from day 17 to day 26 of each cycle.Main outcome measures Main: change in total, exponentially smoothed, average maximum score (total-ESAmax) of 10 common premenstrual syndrome symptoms derived from Trigg's trend analysis and patient satisfaction. Subsidiary: plasma oestradiol and day 21 progesterone levels.Results Main: no difference in change in total-ESAmax between Estraderm 100 μg and 200 μg groups. Greater drop-out rate and greater incidence of side effects attributed to oestrogen in higher dosage group. Satisfaction rate of 45% to 57% at eight months. Subsidiary: 1. Mean (95% CI) oestradiol level of 300 pmol/l (255 to 345) with Estraderm 100 Fg and 573 (494 to 693) with Estraderm 200 pg; 2. Estraderm 100 μg suppresses mid-luteal progesterone from a mean (95% CI) of 353 (28.4 to 427) to 3.4 (2.4 to 4.5).Conclusions Estraderm TTS 100 μg twice weekly is as effective as 200 μg twice weekly in reducing symptom levels in severe premenstrual syndrome but is better tolerated. Estraderm 100 μg suppresses ovulation and results in a mean plasma oestradiol level similar to that observed in a spontaneous cycle.

Notes: Objective To evaluate the effect of 75 mg oestradiol implants on the bone mass of older postmenopausal women with osteoporosis.Design One year prospective-controlled study.Subjects Thirty-two postmenopausal women over 60 years of age and more than five years postmenopausal with low bone density were recruited. Thirty women completed treatment for one year with 75 mg oestradiol implants. The changes in bone density were compared with a control group of 14 women. The side effects with treatment were documented.Main outcome measures Dual energy X-ray absorptiometry of the lumbar spine and proximal femur using Hologic 1000 QDR before treatment and at one year. Plasma oestradiol assays were performed before and after one year.Results The median percentage changes in the treated group after one year was 12.6% at the lumbar spine and 5.22 % at the total hip. The increase in vertebral bone density was greatest in women with low initial bone density (r = 0.35, P 〈 0.05) and those with highest treatment plasma oestradiol levels (r = 0.47, 〉P 〈 0.01). Side effects were common but most were transient and mild in nature.Conclusion 75 mg oestradiol implants significantly increase the bone mineral density at the spine and hip of older postmenopausal women with established osteoporosis.

Notes: Abstract: Corticotropin-releasing factor (CRF) appears to integrate the endocrine, autonomic, immunologic, and behavioral responses of mammals to stress. To investigate further the role of CRF in the CNS, we have begun investigating the usefulness of “antisense knockdown” strategies directed against the CRF receptor using rat anterior pituitary gland primary cell cultures. The 15-mer antisense (5′ CTG-CGG-GCG-CCG-TCC 3′) and “scrambled” control (5′ CGT-CCG-CGC-GCT-GCG 3′) oligonucleotides were synthesized based on the rat CRF receptor sequence just downstream of the initiation codon. In each of four separate experiments, exposure to 10 µmol/L of antisense oligonucleotide for 40–67 h resulted in significant (17–36%) decreases in 125I-ovine CRF binding to pituitary cells as compared with either control (no oligonucleotide) or 10 µmol/L of “scrambled” oligonucleotide. Moreover, compared with scrambled oligonucleotide, exposure to 10 µmol/L of antisense oligonucleotide, which produced a 22% decrease in CRF receptor binding, also resulted in a significant attenuation of the adrenocorticotrophic hormone response following a 30-min challenge with 100 pmol/L of CRF. Thus, CRF receptor antisense oligonucleotides apparently reduce functional expression of CRF receptors. This technique may be useful in studying the kinetics of CRF receptor production and the physiological functions of CRF receptors within the CNS.

Notes: Abstract: The invertebrate phototransduction system is a valuable model of the ubiquitous inositol lipid signalling system. Taking advantage of the ability to obtain relatively large amounts of retinal material from the cephalopod eye, partial protein sequence data were obtained for a 92-kDa component isolated from a detergent-insensitive cytoskeletal fraction of a squid retinal microvillar membrane preparation. Degenerate oligonucleotides, designed on the basis of these sequence data, were used to isolate a full-length cDNA, encoding the 92-kDa component, using both cDNA library screening and 5′-rapid amplification of cDNA ends (5′-RACE) techniques. Comparison of the amino acid sequence encoded by this cDNA with entries in the OWL composite protein sequence database reveals greatest sequence similarity with the products of the Drosophila trp and trpl genes. Greatest variation from the Drosophila Trp protein is seen in the carboxyl-terminal region, which is considerably truncated in the squid protein and which accounts for most of the substantial difference in molecular weight seen between these proteins. This variation may be significant as the carboxyl-terminal domain has been shown to be in the regulation of several ligand-gated channels. The carboxyl-terminal domain has been expressed and shown to interact with calmodulin in a calcium-dependent fashion, thereby supporting this hypothesis. The likely occurrence of other homologues in a variety of systems suggests that this is a novel and important family of regulated ion channels involved in calcium signalling.

Notes: Abstract: Amyloid β-peptide (Aβ) is the principal component of neuritic plaques in the brain in Alzheimer's disease (AD). Recent studies revealed that Aβ can be neurotoxic by a mechanism involving free radical production and loss of cellular ion homeostasis, thus implicating Aβ as a key factor in the pathogenesis of AD. However, other proteins are present in plaques in AD, including the protease thrombin and protease nexin-1 (PN1), a thrombin inhibitor. We therefore tested the hypothesis that thrombin and PN1 modify neuronal vulnerability to Aβ toxicity. In dissociated rat hippocampal cell cultures the toxicity of Aβ was significantly enhanced by coincubation with thrombin, whereas PN1 protected neurons against Aβ toxicity. Aβ induced an increase in levels of intracellular peroxides and calcium. Thrombin enhanced, and PN1 attenuated, the accumulation of peroxides and calcium induced by Aβ. Taken together, these data demonstrate that thrombin and PN1 have opposing effects on neuronal vulnerability to Aβ and suggest that thrombin and PN1 play roles in the pathogenesis of neuronal injury in AD.

Notes: Abstract: Evidence from in vitro studies suggests that excitotoxic neuronal degeneration can occur by either an acute or delayed mechanism. Studies of the acute mechanism in isolated chick embryo retina using histological methods indicate that this process is rapidly triggered by activation of glutamate receptors of either the N-methyl-d-aspartate (NMDA) or non-NMDA subtypes. The delayed mechanism, studied primarily in cortical and hippocampal cell cultures prepared from embryonic rodent brain, requires activation of NMDA receptors. In these cell culture systems, stimulation of non-NMDA receptors does not rapidly trigger delayed neuronal degeneration, or does so only indirectly, via activation of NMDA receptors secondary to glutamate release. To provide a more valid basis for comparison of these two mechanisms, we have modified the isolated chick embryo retina model to permit studies of delayed as well as acute excitotoxic neurodegeneration. Retinas maintained for 24 h exhibited no morphological or biochemical signs of damage. Retinal damage was assessed by measuring lactate dehydrogenase (LDH) present in the medium at various times after exposure to agonists and normalized to total LDH in each retina. Glutamate exposure (1 mM, 30 min) did not result in LDH release by the end of the exposure period, but LDH was released over the following 24 h. Briefer periods also led to substantial LDH release. Incubation in the presence of NMDA, or the non-NMDA agonists kainate (KA) or α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), led rapidly to delayed LDH release. NMDA and AMPA were more potent than glutamate, but high concentrations of glutamate led to more LDH release than high concentrations of these agonists. KA was a powerful excitotoxin, providing more LDH release than glutamate, NMDA, or AMPA at every concentration tested. The delayed LDH release induced by glutamate involved activation of both NMDA and non-NMDA receptors, as a combination of receptor-selective antagonists was necessary to provide complete blockade. These results indicate that glutamate, NMDA, AMPA, and KA all cause delayed as well as acute excitotoxic damage in the retina. It is interesting that brief exposure to the non-NMDA receptor agonists, in relatively low concentrations, led to delayed LDH release. This is different than in other in vitro models of delayed excitotoxic neurodegeneration.