Search

IMT504 is a non-CPG, non-coding synthetic oligodeoxinucleotide (ODN) with immunomodulatory properties and a novel inhibitory role in pain transmission, exerting long-lasting analgesic effects upon multiple systemic administrations. However, its mechanisms of anti-nociceptive action are still poorly understood. In the present study in male adult rats undergoing complete Freund’s adjuvant-induced hindpaw inflammation, we focused in the analysis of the immunomodulatory role of IMT504 over the cellular infiltrate, the impact on the inflammatory milieu, and the correlation with its anti-allodynic role. By means of behavioral analysis, we determined that a single subcutaneous administration of 6 mg/kg of IMT504 is sufficient to exert a 6-week-long full reversal of mechanical and cold allodynia, compromising neither acute pain perception nor locomotor activity. Importantly, we found that the anti-nociceptive effects of systemic IMT504, plus quick reductions in hindpaw edema, were associated with a modulatory action upon cellular infiltrate of B-cells, macrophages and CD8+ T-cells populations. Accordingly, we observed a profound downregulation of several inflammatory leukocyte adhesion proteins, chemokines and cytokines, as well as of β-endorphin and an increase in the anti-inflammatory cytokine, interleukin-10. Altogether, we demonstrate that at least part of the anti-nociceptive actions of IMT504 relate to the modulation of the peripheral immune system at the site of injury, favoring a switch from pro- to anti-inflammatory conditions, and provide further support to its use against chronic inflammatory pain.

The prevalence of age-related macular degeneration (AMD) has increased in the last years. Although anti-VEGF agents have improved the prognosis of exudative AMD, dry AMD has still devastating effects on elderly people vision. Oxidative stress and inflammation are mechanisms involved in AMD pathogenesis and its progression. Molecular pathways involving epidermal growth factor receptor (EGFR), bone morphogenetic protein (BMP4) and the nuclear erythroid related factor 2 (Nrf2) are behind oxidative stress in AMD due to their participation in antioxidant cellular pathways. As a consequence of the disbalance produced in the antioxidant mechanisms, there is an activation of innate and adaptative immune response with cell recruitment, changes in complement factors expression, and modification of cellular milieu. Different therapies are being studied to treat dry AMD based on the possible effects on antioxidant molecular pathways or their action on the immune response. There is a wide range of treatments presented in this review, from natural antioxidant compounds to cell and gene therapy, based on their mechanisms. Finally, we hypothesize that alpha-1-antitrypsin (AAT), an anti-inflammatory and immunomodulatory molecule that can also modulate antioxidant cellular defenses, could be a good candidate for testing in AMD. This article is part of the special ssue on 'The Quest for Disease-Modifying Therapies for Neurodegenerative Disorders'.

Velcro fastening straps are commonly used to secure a scoliosis brace around the upper body and apply corrective forces to the spine. However, strap loosening and tension loss have been reported that reduce spinal correction and treatment efficacy. A novel fastening device, or controlled tension unit (CTU), was designed to overcome these limitations. A scoliosis analog model (SAM) was used to biomechanically compare the CTU fasteners and posterior Velcro straps on a conventional brace (CB) as well as on a modified brace (MB) that included a dynamic cantilever apical pad section. Brace configurations tested were (1) CB with posterior Velcro straps, (2) CB with posterior CTU fasteners, (3) MB with posterior Velcro straps, and (4) MB with posterior CTU fasteners. MB configurations were tested with 0 N, 35.6 N, and 71.2 N CTU fasteners applied across the apical pad flap. Three-dimensional forces and moments were measured at both ends of the SAM. The CTU fasteners provided the same corrective spinal loads as Velcro straps when tensioned to the same level on the CB configuration and can be used as an alternative fastening system. Dynamically loading the apical flap increased the distractive forces applied to the spine without affecting tension in the fastening straps.

BACKGROUND: Use of biological or synthetic mesh might improve outcomes of immediate implant-based breast reconstruction-breast reconstruction with implants or expanders at the time of mastectomy-but there is a lack of high-quality evidence to support the safety or effectiveness of the technique. We aimed to establish the short-term safety of immediate implant-based breast reconstruction performed with and without mesh, to inform the feasibility of undertaking a future randomised clinical trial comparing different breast reconstruction techniques.METHODS: In this prospective, multicentre cohort study, we consecutively recruited women aged 16 years or older who had any type of immediate implant-based breast reconstruction for malignancy or risk reduction, with any technique, at 81 participating breast and plastic surgical units in the UK. Data about patient demographics and operative, oncological, and complication details were collected before and after surgery. Outcomes of interest were implant loss (defined as unplanned removal of the expander or implant), infection requiring treatment with antibiotics or surgery, unplanned return to theatre, and unplanned re-admission to hospital for complications of reconstructive surgery, up to 3 months after reconstruction and assessed by clinical review or patient self-report. Follow-up is complete. The study is registered with the ISRCTN Registry, number ISRCTN37664281.FINDINGS: Between Feb 1, 2014, and June 30, 2016, 2108 patients had 2655 mastectomies with immediate implant-based breast reconstruction at 81 units across the UK. 1650 (78%) patients had planned single-stage reconstructions (including 12 patients who had a different technique per breast). 1376 (65%) patients had reconstruction with biological (1133 [54%]) or synthetic (243 [12%]) mesh, 181 (9%) had non-mesh submuscular or subfascial implants, 440 (21%) had dermal sling implants, 42 (2%) had pre-pectoral implants, and 79 (4%) had other or a combination of implants. 3-month outcome data were available for 2081 (99%) patients. Of these patients, 182 (9%, 95% CI 8-10) experienced implant loss, 372 (18%, 16-20) required re-admission to hospital, and 370 (18%, 16-20) required return to theatre for complications within 3 months of their initial surgery. 522 (25%, 95% CI 23-27) patients required treatment for an infection. The rates of all of these complications are higher than those in the National Quality Standards (INTERPRETATION: Complications after immediate implant-based breast reconstruction are higher than recommended by national standards. A randomised clinical trial is needed to establish the optimal approach to immediate implant-based breast reconstruction.FUNDING: National Institute for Health Research, Association of Breast Surgery, and British Association of Plastic, Reconstructive and Aesthetic Surgeons.

Aged-related macular degeneration (AMD), a prevalent chronic disease leading to blindness, is associated with oxidative damage of the retinal pigment epithelium (RPE). Ilex paraguariensis (yerba mate, YM), widely consumed in South America, is an excellent source of antioxidants and could prevent RPE cell impairment. Therefore, we evaluated the effects of YM extracts or caffeic (CAF) and chlorogenic (CHL) acids, two major Ilex polyphenols on cell death or premature senescence in a cell line derived from human RPE (ARPE-19). Cultures were incubated with YM, CAF, CHL or appropriate controls and then exposed to H2O2. Protection was correlated with decreases of reactive oxygen species (ROS) and DNA breaks, phosphorylation of the cAMP response element (CREB) and increases of the nuclear factor erythroid 2-related factor 2 (NRF2), BCL2, superoxide dismutase (SOD2) and sirtuin 1 (SIRT1). These results support the protective role of YM and its polyphenols against oxidative stress induced RPE injury.

Death of retinal photoreceptors is the basis of prevalent blinding diseases. Since steroids might have a therapeutic role in retinal degenerations, we compared the protective effects of dexamethasone and progesterone on photoreceptor death induced by mifepristone and light exposure. Therefore, we studied the effective protection doses for each steroid in the two models. In addition, we analyzed changes in the levels of pro- and antiapoptotic molecules, glucocorticoid receptors α and β (GRα and GRβ), and rhodopsin under conditions of successful protection and photoreceptor survival. Mifepristone and light exposure selectively damaged photoreceptors. In light exposed retinas, photoreceptors mainly disappeared in the dorsotemporal region, while mifepristone produced a uniform damage. Dexamethasone and progesterone, at the same dose of 4 mg/kg/day for 2 days, preserved over 88% photoreceptor nuclei in both models. Assessment of cell death regulators showed that, in control retinas, both steroids activated BCL-XL, a prosurvival molecule, and decreased BID, a proapoptotic regulator. After steroid treatment of damaged retinas, BCL-XL, BCL2 and BAX showed characteristic patterns depending on the use of dexamethasone or progesterone on mifepristone or light exposed retinas. By contrast, BID decreased with any injury-steroid combination. Changes in GRα or GRβ levels did not correlate with survival but were consistent with a mechanism of ligand induced downregulation of receptor expression. GRβ might be upregulated by progesterone. Both dexamethasone and progesterone increased retinal rhodopsin stores, suggesting a link between photoreceptor protection and transduction pathways. Results show that dexamethasone and progesterone induced comparable but not identical protection responses in each model. Fil: Marquioni Ramella, Melisa Daniela. Universidad Austral. Facultad de Ciencias Biomédicas. Instituto de Investigaciones en Medicina Traslacional. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Medicina Traslacional; Argentina Fil: Cubilla, Marisa Angelica. Universidad Austral. Facultad de Ciencias Biomédicas. Instituto de Investigaciones en Medicina Traslacional. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Medicina Traslacional; Argentina Fil: Bermudez, Vicente. Universidad Austral. Facultad de Ciencias Biomédicas. Instituto de Investigaciones en Medicina Traslacional. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Medicina Traslacional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones Bioquímicas de Bahía Blanca. Universidad Nacional del Sur. Instituto de Investigaciones Bioquímicas de Bahía Blanca; Argentina Fil: Tate, Pablo Sebastián. Universidad Austral. Facultad de Ciencias Biomédicas. Instituto de Investigaciones en Medicina Traslacional. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Medicina Traslacional; Argentina Fil: Marazita, Mariela Claudia. Universidad Austral. Facultad de Ciencias Biomédicas. Instituto de Investigaciones en Medicina Traslacional. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Medicina Traslacional; Argentina Fil: Suburo, Angela Maria. Universidad Austral. Facultad de Ciencias Biomédicas. Instituto de Investigaciones en Medicina Traslacional. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones en Medicina Traslacional; Argentina

Background The optimal timing of cholecystectomy for patients admitted with acute gallbladder pathology is unclear. Some studies have shown that emergency cholecystectomy during the index admission can reduce length of hospital stay with similar rates of conversion to open surgery, complications and mortality compared with a ‘delayed’ operation following discharge. Others have reported that cholecystectomy during the index acute admission results in higher morbidity, extended length of stay and increased costs. This study examined the cost-effectiveness of emergency versus delayed cholecystectomy for acute benign gallbladder disease. Methods Using data from a prospective population-based cohort study examining the outcomes of cholecystectomy in the UK and Ireland, a model-based cost–utility analysis was conducted from the perspective of the UK National Health Service, with a 1-year time horizon for costs and outcomes. Probabilistic sensitivity analysis was used to investigate the impact of parameter uncertainty on the results obtained from the model. Results Emergency cholecystectomy was found to be less costly (£4570 versus £4720; €5484 versus €5664) and more effective (0·8868 versus 0·8662 QALYs) than delayed cholecystectomy. Probabilistic sensitivity analysis showed that the emergency strategy is more than 60 per cent likely to be cost-effective across willingness-to-pay values for the QALY from £0 to £100 000 (€0–120 000). Conclusion Emergency cholecystectomy is less costly and more effective than delayed cholecystectomy. This approach is likely to be beneficial to patients in terms of improved health outcomes and to the healthcare provider owing to the reduced costs.

Introduction Pan-speciality consensus guidance advocates mandatory emergency general surgery (EGS) training modules for specialist registrars (StRs). This pilot study evaluated the impact of EGS modules aimed at StRs over 1 year. Methods Eleven StRs were allocated a focused 4-week EGS module, in addition to the standard 1:12 on-call duty rota, in a tertiary surgical centre. Primary outcome measures included the number of indicative emergency operations and validated Procedure Based Assessments (PBAs) performed, both during the EGS module and over the training year. Results StRs performed a median of 11 (range 5–15) laparotomies during the EGS module versus 31 (range 9-49) over the whole training year. StRs attended 43.7% of available laparotomies during the module (range 24.1–63.7%). EGS modules provided more than one-third of the total emergency laparotomy experience, and a quarter of the emergency colectomy, appendicectomy and Hartmann’s procedure experience. There were no differences in EGS module-related outcomes between junior and senior StRs. Significantly more PBAs related to laparotomy and segmental colectomy were completed during EGS modules than the on-call duty rota, at 32% versus 14% (pConclusions These findings provide an important baseline when considering future modular EGS training.

Background: Anaemia is the commonest medical disorder that contributes significantly to maternal morbidity and mortality, preterm delivery, intrauterine growth restriction. Pregnant women are particularly vulnerable to anaemia because they have dual iron requirements both for their growth and growth of foetus. A high proportion of women in both industrialized and developing countries become anaemic during pregnancy. Intravenous iron therapy is safe convenient and effective than oral iron therapy in prevention of iron deficiency anaemia when compliance is the problem. The aim of this study is to compare the efficacy, safety and acceptability of intravenous iron Vs oral iron in prevention of iron deficiency anaemia during pregnancy. The objective of the present research was to study the efficacy, safety and acceptability of oral iron (ferrous fumarate) versus intravenous iron (iron sucrose) for the prevention of iron deficiency anaemia during pregnancy.Methods: It was a prospective comparative case control study without blinding including 400 registered antenatal women in SKNMC and GH, Narhe, Pune. Results were based on collection and analysis of data from samples within study population.Results: There was no significant difference in mean haemoglobin rise between oral group and IV group but there is significant difference between mean ferritin levels between oral group and IV group. In IV group ferritin levels at 36 weeks were almost 1.8 times more than oral group. Acceptability and convenience of IV iron was significantly more than oral iron.Conclusions: Intravenous iron therapy in the form of three divided doses, one in each trimester can be safely used in the antenatal woman as an alternative to prophylactic iron tablets for prevention of iron deficiency anaemia especially in women who are non-compliant or does not tolerate oral iron tablets.

The voltage-gated ‘glial’ sodium channel NaG belongs to a distinct molecular class within the multi-gene family of mammalian sodium channels. Originally found in central and peripheral glia, NaG has since been detected in neurons in rat dorsal root ganglia (DRG) and may play a role in Schwann cell-axon interactions. We have studied the presence of NaG-like immunoreactivity in the intact and injured human peripheral nervous system using a specific affinity-purified antibody. Nerve fibres in normal and injured peripheral nerves and normal skin exhibited intense NaG-immunoreactivity. Numerous NaG-immunoreactive nerve fibres surrounded neuronal cell bodies within postmortem control DRG, and in DRG avulsed from the spinal cord (i.e. after traumatic central axotomy). There were no significant differences in the pattern of NaG immunostaining between control and avulsed DRG, or with delay after injury. Generally, the neuronal cell bodies were only very weakly immunoreactive to NaG, indicating that the NaG immunoreactivity was predominantly in Schwann cells/myelin. In accord, we demonstrated NaG immunostaining in cultured human and rat Schwann cells, and in distal nerve after wallerian degeneration. NaG thus appears to be a useful new marker for Schwann cells in the human PNS, and a role in neuropathy deserves investigation.

Results. SLNs were identified in 672 of 758 patients (89%). Of the patients with SLNs identified, 403 patients (60%) had more than 1 SLN removed (mean, 1.96 SLN/patient) and 207 patients (31%) had nodal metastases. The use of filtered or unfiltered technetium sulfur colloid had no impact on the number of SLNs identified. Overall, 33% of histologically positive SLNs had no evidence of blue dye staining. Of those patients with multiple SLNs removed, histologically positive SLNs were found in 130 patients. In 15 of these 130 patients (11.5%), the hottest SLN was negative when a less radioactive node was positive for tumor. If only the hottest node had been removed, the false-negative rate would have been 13.0% versus 5.8% when all nodes with 10% or more of the ex vivo count of the hottest node were removed (P = .01). Conclusions. These data support the policy that all blue nodes and all nodes with 10% or more of the ex vivo count of the hottest SLN should be harvested for optimal nodal staging. (Surgery 2000;128:139-44.)

PURPOSE: Previous studies have demonstrated the feasibility of sentinel lymph node (SLN) biopsy for nodal staging of patients with breast cancer. However, unacceptably high false-negative rates have been reported in several studies, raising doubt about the applicability of this technique in widespread surgical practice. Controversy persists regarding the optimal technique for correctly identifying the SLN. Some investigators advocate SLN biopsy using injection of a vital blue dye, others recommend radioactive colloid, and still others recommend the use of both agents together. PATIENTS AND METHODS: A total of 806 patients were enrolled by 99 surgeons. SLN biopsy was performed by single-agent (blue dye alone or radioactive colloid alone) or dual-agent injection at the discretion of the operating surgeon. All patients underwent attempted SLN biopsy followed by completion level I/II axillary lymph node dissection to determine the false-negative rate. RESULTS: There was no significant difference (86% v 90%) in the SLN identification rate among patients who underwent single- versus dual-agent injection. The false-negative rates were 11.8% and 5.8% for single- versus dual-agent injection, respectively (P < .05). Dual-agent injection resulted in a greater mean number of SLNs identified per patient (2.1 v 1.5; P < .0001). The SLN identification rate was significantly less for patients older than 50 years as compared with that of younger patients (87.6% v 92.6%; P = .03). Upper-outer quadrant tumor location was associated with an increased likelihood of a false-negative result compared with all other locations (11.2% v 3.9%; P < .05). CONCLUSION: In multi-institutional practice, SLN biopsy using dual-agent injection provides optimal sensitivity for detection of nodal metastases. The acceptable SLN identification and false-negative rates associated with the dual-agent injection technique indicate that this procedure is a suitable alternative to routine axillary dissection across a wide spectrum of surgical practice and hospital environments.

To evaluate the role of preoperative lymphoscintigraphy in sentinel lymph node (SLN) biopsy for breast cancer.Numerous studies have demonstrated that SLN biopsy can be used to stage axillary lymph nodes for breast cancer. SLN biopsy is performed using injection of radioactive colloid, blue dye, or both. When radioactive colloid is used, a preoperative lymphoscintigram (nuclear medicine scan) is often obtained to ease SLN identification. Whether a preoperative lymphoscintigram adds diagnostic accuracy to offset the additional time and cost required is not clear.After informed consent was obtained, 805 patients were enrolled in the University of Louisville Breast Cancer Sentinel Lymph Node Study, a multiinstitutional study involving 99 surgeons. Patients with clinical stage T1-2, N0 breast cancer were eligible for the study. All patients underwent SLN biopsy, followed by level I/II axillary dissection. Preoperative lymphoscintigraphy was performed at the discretion of the individual surgeon. Biopsy of nonaxillary SLNs was not required in the protocol. Chi-square analysis and analysis of variance were used for statistical comparison.Radioactive colloid injection was performed in 588 patients. In 560, peritumoral injection of isosulfan blue dye was also performed. A preoperative lymphoscintigram was obtained in 348 of the 588 patients (59%). The SLN was identified in 221 of 240 patients (92.1%) who did not undergo a preoperative lymphoscintigram, with a false-negative rate of 1.6%. In the 348 patients who underwent a preoperative lymphoscintigram, the SLN was identified in 310 (89.1%), with a false-negative rate of 8.7%. A mean of 2.2 and 2. 0 SLNs per patient were removed in the groups without and with a preoperative lymphoscintigram, respectively. There was no statistically significant difference in the SLN identification rate, false-negative rate, or number of SLNs removed when a preoperative lymphoscintigram was obtained.Preoperative lymphoscintigraphy does not improve the ability to identify axillary SLN during surgery, nor does it decrease the false-negative rate. Routine preoperative lymphoscintigraphy is not necessary for the identification of axillary SLNs in breast cancer.

The tetrodotoxin-resistant (TTX-R) voltage-gated sodium channel SNS/PN3 and the newly discovered NaN/SNS2 are expressed in sensory neurones, particularly in nociceptors. Using specific antibodies, we have studied, for the first time in humans, the presence of SNS/PN3 and NaN/SNS2 in peripheral nerves, including tissues from patients with chronic neurogenic pain. In brachial plexus injury patients, there was an acute decrease of SNS/PN3- and NaN/SNS2-like immunoreactivity in sensory cell bodies of cervical dorsal root ganglia (DRG) whose central axons had been avulsed from spinal cord, with gradual return of the immunoreactivity to control levels over months. In contrast, there was increased intensity of immunoreactivity to both channels in some peripheral nerve fibers just proximal to the site of injury in brachial plexus trunks, and in neuromas. These findings suggest that the expression of these sodium channels in neuronal cell bodies is reduced after spinal cord root avulsion injury in man, but that pre-synthesized channel proteins may undergo translocation with accumulation at sites of nerve injury, as in animal models of peripheral axotomy. The latter may contribute to positive symptoms, as our patients all showed a positive Tinel's sign. Nerve terminals in distal limb neuromas and skin from patients with chronic local hyperalgesia and allodynia all showed marked increases of SNS/PN3-immunoreactive fibers, but little or no NaN/SNS2-immunoreactivity, suggesting that the former may be related to the persistent hypersensitive state. Axonal immunoreactivity to both channels was similar to control nerves in sural nerve biopsies in a selection of neuropathies, irrespective of nerve inflammation, demyelination or spontaneous pain, including a patient with congenital insensitivity to pain. Our studies suggest that the best target for SNS/PN3 blocking agents is likely to be chronic local hypersensitivity.

The neutral and basic amino acid transporter (NBAT) facilitates sodium-independent transport of L-amino acids in renal and intestinal epithelial cells and has been postulated to play a similar role in neurons. In previous studies, NBAT has been detected within enteric and brainstem autonomic neurons in a distribution similar to that of constitutive nitric oxide synthase (cNOS). Furthermore, L-arginine, the required precursor for nitric oxide synthesis, is an excellent NBAT substrate. Together, these findings suggest that NBAT may play a role in the regulation of nitric oxide synthesis, through the control of precursor availability. To gain insight into the potential physiological role of NBAT in central neurons, we used an antipeptide antiserum to examine the light and electron microscopic immunocytochemical localization of NBAT in the rat forebrain and to compare this distribution with that of cNOS. Immunolabeling for NBAT was detected within perikarya and dendrite-like processes that were most numerous in the frontal and cingulate cortex, the ventral striatum, the central amygdala, and the bed nucleus of the stria terminalis. Labeled varicose axonal processes were distributed most densely in the agranular insular cortex and the paraventricular nuclei of the thalamus and hypothalamus (PVH). Electron microscopy showed that immunogold labeling for NBAT was distributed along plasmalemmal and vacuolar membranes within somata, dendrites, and axonal profiles. Many of the NBAT-containing somata and dendrites contained detectable cNOS. Our results suggest that expression of NBAT may provide specific populations of cNOS-containing forebrain neurons with a unique mechanism for regulating somatodendritic synthesis of nitric oxide.

Nearly identical proteins (denoted NAA-Tr, rBAT, D2, NBAT), cloned from mammalian kidneys, induce a largely sodium-independent high-affinity transport system for cystine, basic amino acids, and some neutral amino acids in Xenopus oocytes (system b0,+-like). Mutations in the human NBAT gene have been found in several type I cystinurics. In kidney, NBAT is associated with a second, smaller protein (approximately 45 kDa), and this heterodimer has been proposed to be the minimal functional unit of the renal cystine transporter (Wang, Y., and Tate, S. S. (1995) FEBS Lett. 368, 389-392). To delineate regions minimally required for functional expression in oocytes, we constructed a series of C-terminal truncated mutants of rat kidney NBAT (wild-type (WT), 683 amino acids). Expression of these mutants in oocytes yielded an unusual bimodal pattern for the induction of amino acid transport activity. Thus, initial C-terminal truncations aborted elicitation of transport activity. The next mutant in the series, Delta588-683, exhibited most of the transport-inducing potential inherent in the WT/NBAT. Further deletions again attenuated transport activity. Although both the WT/NBAT and the truncated mutant, Delta588-683, induce qualitatively similar transport systems, the two forms of the protein exhibit contrasting sensitivities toward a point mutation in which the cysteine residue at position 111 was mutated to serine. This mutation did not greatly affect induction of transport by the WT/NBAT; however, the Delta588-683 mutant was inactivated by this mutation. Our data further suggest that cysteine 111 is probably the site of disulfide linkage with an approximately 45-kDa oocyte protein producing a complex equivalent to that seen in kidney membranes.

Alzheimer's disease (AD), the most common primary dementing disorder, results in devastating clinical and socio-economic consequences, and is a leading cause of death among the elderly. Despite recent advances in the neurobiology of AD, identification of effective treatment strategies has remained frustratingly elusive. Administration of currently available cholinergic drugs improves symptoms in some patients with AD, but may be associated with efficacy-limiting adverse effects. Moreover, it is not yet known whether cholinergic drugs have the potential to alter the progression of AD pathology. In contrast, cumulative evidence from basic neuroscience and clinical research demonstrates that oestrogen has significant neuromodulatory and neuroprotective properties. Furthermore, preliminary evidence from clinical studies indicates that oestrogen replacement therapy can significantly enhance cognitive function in postmenopausal women with AD, and reduce the risk for developing the disease. However, long-term administration of oestrogen is associated with potentially serious adverse effects, including increased risk for developing malignancies of the uterus and the breast. Fortunately, tissue-specific analogues of oestrogen are in development that could specifically target the functions of the brain, and may be devoid of the cancer-inducing and feminising properties of the hormone. Availability of these analogues will make it feasible to treat AD with oestrogen in both women and men. However, findings of preliminary studies, although promising, need to be confirmed in larger, controlled clinical trials before the role of oestrogen in the treatment and prevention of AD can be firmly established.

The purpose of this study was to test a theoretical model developed to explain family satisfaction among 171 caregivers of elderly parents. Using LISREL to estimate path coefficients, the findings support family satisfaction as directly and indirectly influenced by reciprocity, emotional well-being and family functioning. Explanatory variables accounted for 70% of the variance in predicting family satisfaction. Intrinsic rewards derived from giving care, positive affect, and family functioning contributed to higher levels of family satisfaction, while dysphoria contributed significantly to lower levels. Family satisfaction was also indirectly influenced by positive and negative exchanges received by the parent. Increasing caregivers awareness of the reciprocal nature of their relationships with all family members may be an effective strategy in helping them appreciate their contribution to the well-being of their parents and achieve satisfaction in the caregiving role.

This study highlights the differences in knowledge and misconceptions about cholesterol according to gender and race in the United States. Data were obtained from a randomly selected national sample of 1,068 adults. Respondents were asked a series of true-false questions covering such topics as recommended cholesterol levels, how cholesterol is reduced, the effect of diet, smoking habits, and exercise on cholesterol levels, etc. The results indicated that the knowledge level differed according to gender and race.

High-titer, site-specific antibodies have been produced against the rat kidney broad-spectrum, sodium-independent neutral and basic amino acid transporter (NBAA-Tr) whose cDNA we cloned earlier. These antibodies have allowed us to characterize the transporter protein in normal rat tissues and in various cellular and in vitro expression systems. Western analysis detected 84- to 87-kDa glycosylated species enriched in rat renal and jejunal epithelial cell brush border membranes. In vitro translation of NBAA-Tr complementary RNA in the rabbit reticulocyte lysate system yielded a 78-kDa protein, a molecular mass that was predicted by the amino acid sequence deduced from the cloned cDNA. Translation in the presence of rough microsomal membranes yielded a glycosylated 89-kDa species. Glycosylated 87- to 89-kDa species were also expressed in Xenopus oocytes microinjected with NBAA-Tr complementary RNA and in COS-7 cells transfected with NBAA-Tr cDNA. Localization of NBAA-Tr in renal and intestinal brush border membranes is consistent with its proposed role in transepithelial transport of amino acids.

Forty-eight cases of melanoma occurring in patients under 20 years of age were reviewed from a 23-year period at a single center. Fourteen of the patients were preadolescent children and 44 were Caucasian. Histological review of 44 available primary tumors showed only superficial spreading and nodular types. Thickness ranged from 0.23 mm to 8.50 mm, with a median of 1.03 mm. Ulceration was present in 7%, necrosis in 35%, evidence of regression in 16%, and antecedent nevus in 49% of the cases. The overall 5-year survival is 77%, with a median follow-up of 48 months. There is no detectable survival difference between preadolescent children and adolescents. Several treatment failures occurred after improper biopsy and/or inaccurate original diagnosis of Spitz's nevus. Of 38 stage I and II patients given definitive surgical treatment by the authors, the 5-year survival is 90%. Although histological confusion with Spitz's nevi occasionally occurs, melanoma in this age group can be treated with good results.

An appreciable fraction of the sulphur present in the mammal occurs in the form of glutathione, whose concentration in various tissues ranges from about 0.8 to about 8 mM; the extracellular concentration of glutatione (largely present as the disulphide) is in the micromolecular range. The synthesis of glutathione and its utilization take place by the reactions of the gamma-glutamyl cycle, which include those catalysed by gamma-glutamylcysteine and glutathione synthetases, gamma-glutamyl transpeptidase, cysteinylglycinase, gamma-glutamyl cyclotransferease, and 5-oxoprolinase. gamma-Glutamyl transpeptidase catalyses transpeptidation (with amino acids and dipeptides) and hydrolysis reactions with both blutathione and its disulphide. The transpeptidase is membrane-boudn, apparently to the outer surface of the cell, and is found in certain epithelial cells in anatomical sites that are involved in transport and secretory activities (e.g., renal tubule, jejunal villi, choroid plexus, ciliary body). Evidence that the reactions of the gamma-glutamyl cycle take place in vivo has come from studies with labelled metabolites and selective enzyme inhibitors, and on inborn errors of metabolism associated with specific enzyme deficiencies. Inhibition in vivo of gamma-glutamyl cyclotransferase and 5-oxoprolinase leads, respectively, to decreased and increased renal levels of 5-oxoproline. Administration of a specific inhibitor of gamma-glutamylcysteine synthetase, such as buthionine sulphoximine, leads to a rapid decline in the glutamylcysteine synthetase, such as buthionine sulphoximine, leads to a rapid decline in the glutathione level of the kidney and other tissues, reflecting the appreciable rate of glutathione utilization. When gamma-glutamyl transpeptidase is inhibited in vivo by injection of L- or D-gamma-glutamyl-(o-carboxy)phenylhydrazide, there is extensive glutathionuria and the blood plasma level of glutathione increases. Studies in which inhibitors of glutathione synthesis and transpeptidation were given to mice showed that transport of intracellular glutathione to membrane-bound transpeptidase is a discrete step in the gamma-glutamyl cycle, and that the level of plasma glutatione reflects (a) synthesis of glutathione and its export by liver, muscle, and other tissues and (b) utilization of glutatione by kidney and other tissues. Studies on several lymphoid cell lines show that these cells also actively translocate glutathione out of the cell. A summary scheme is given for the metabolism of glutathione in which glutathione is translocated to the cell membrane where it may be utilized as such or oxidized to glutathione disulphide. Oxidation is inhibited, and transpeptidation is promoted by the presence of amino acids that are substrates of the transpeptidase. Glutathione exported from cells that have membrane-bound transpeptidase may be recovered by the cell transport of gamma-glutamyl amino acids and free amino acids...

We demonstrate that poly (A+)RNA isolated from catfish barbels directs the expression of functional amino acid taste receptors in the Xenopus oocyte. The activity of these receptors is monitored in ovo by the two electrode voltage clamp technique. Specific conductance changes recorded in response to amino acid stimulation are analogous to those recorded electrophysiologically from intact catfish barbels. These responses exhibit specificity, reproducibility, rapid onset and termination, and desensitization to repetitive stimulation. A functional assay system that encompasses the full complement of transduction events from the ligand-receptor interaction to subsequent conductance changes is necessary to identify molecular components responsible for these events. Our results demonstrate that the Xenopus oocyte can be used to characterize and identify clones coding for amino acid taste receptors analogous to its use in studying receptor molecules for other neuroactive compounds.

The Xenopus oocyte is widely used to study the various aspects of eukaryotic cell structure and function. It is also being used increasingly in expression cloning of cDNAs encoding proteins for which there are no structural data. One of the drawbacks of the Xenopus oocyte system is that individual oocytes taken at the same time from the same frog vary considerably in the amount of protein synthesized from the same amount of injected mRNA. In this report we describe the preparation and use of the mRNA for a secreted mutant form of human placental alkaline phosphatase as an internal, coinjected standard to monitor translation in oocytes. Secreted alkaline phosphatase can be readily determined in the medium of cultured oocytes by using a standard colorimetric assay. The amounts of alkaline phosphatase secreted into the medium were shown to parallel the level of expression of two membrane proteins. This permits rapid identification and selection of those oocytes that efficiently express injected mRNAs. The procedure yields more precise data and results in an enormous saving of time and expense, especially in investigations that involve complex measurements on individual oocytes.

Textile composites include woven, braided, and knitted fabrics. Textile composites are considered when out-of-plane properties are also important. Textile composites generally have better dimensional stability, out-of-plane properties, and impact and delamination resistance. The natural conformability of biaxial braids makes them more cost competitive than woven fabric. These material systems are gaining popularity, in particular for the small business jets, where FAA requires take off weights of 5670 kgf or less. The vacuum assisted resin transfer molding (VARTM) process has proven to be low in cost compared to resin transfer molding (RTM). Thus, the combination of biaxial braids and the VARTM process is likely to considerably reduce overall costs. Before the braids can be confidently used in the primary structures, it is necessary to understand the performance of biaxial braided composites under various loading conditions and especially under fatigue. This will reduce uncertainty and hence reduce the factor of safety in the design This research addresses viscoelastic effects on fatigue behavior of carbon/epoxy braided composites. It is observed that braided composites exhibit creep and stress relaxation. Further it is observed that frequency in axial fatigue loading plays dominant role in fatigue life, but very little role in fatigue failure mechanisms. Rate of stiffness degradation is greatly affected by frequency. These entire phenomena such as creep, stress relaxation, frequency effect, and dependency of stiffness on rate of loading indicate the viscoelastic behavior of braided composites. In this research different tests were performed to confirm viscoelastic behavior of braided composites. Axial tension-tension fatigue tests were conducted at different frequencies and stiffness degradation was studied.Copyright © 2006 by ASME

The effects of breathing pattern and inspired air conditions on the volume and content of exhaled breath condensate (EBC) were investigated.Total exhaled water (TEW), EBC volume, pH, nitrite and protein concentrations were measured in three groups of 10 healthy subjects breathing into a condenser at different target minute ventilations (Vm), tidal volumes (Vt), and inspired air conditions.The volumes of both TEW and EBC increased significantly with Vm. For Vm 7.5, 15 and 22.5 l/min, mean (SD) EBC was 627 (258) microl, 1019 (313) microl, and 1358 (364) microl, respectively (p0.001) and TEW was 1879 (378) microl, 2986 (496) microl, and 4679 (700) microl, respectively (p0.001). TEW was significantly higher than EBC, reflecting a condenser efficiency of 40% at a target Vm of 7.5 l/min which reduced to 29% at Vm 22.5 l/min. Lower Vt gave less TEW than higher Vt (26.6 v 30.7 microl/l, mean difference 4.1 (95% CI 2.6 to 5.6), p0.001) and a smaller EBC volume (4.3 v 7.6 microl/l, mean difference 3.4 (95% CI 2.3 to 4.5), p0.001). Cooler and drier inspired air yielded less water vapour and less breath condensate than standard conditions (p0.05). Changes in the breathing pattern had no effect on EBC protein and nitrite concentrations and pH.These results show that condensate volume can be increased by using high Vt and increased Vm without compromising the dilution of the sample.

Voluntary bite forces were recorded at varying periods in 35 males treated with rigid internal fixation for fractures of the mandibular angle. Bite forces were also obtained in 29 male controls for comparison. It was found that molar bite forces in patients were significantly less than in controls for several weeks after surgery. Further, molar bite forces on the side of the fracture were significantly less than on the nonfractured side. The results of this study indicate that recommendations for the amount of fixation required for a given fracture may be reduced.

Distraction osteogenesis has gained acceptance as a viable modality for lengthening hypoplastic skeletal structures in the maxillofacial region. A case of the application of this technique to advance the maxilla in an unrepaired bilateral alveolar cleft via a transoral approach is presented. The distraction devices were applied bilaterally to the zygomatic buttress region with the activating arms protruding from the oral cavity. A high Le Fort I osteotomy was performed under general anesthesia and, prior to distraction, the three maxillary segments were unified with an occlusal acrylic splint. Activation was begun 6 days after placement, at a rate of 1 mm per day, until the planned maxillary advancement had been achieved. An 8-week period of consolidation was allowed prior to removal of the devices.

Alcohol intoxication frequently contributes to the occurrence of traumatic brain injury. Few studies, however, have examined whether acute pre-injury alcohol intoxication or premorbid history of alcohol abuse exacerbate cognitive impairments that commonly result from traumatic brain injury. This study examined the influence of blood alcohol level at time of hospital admission on cognitive functioning during the post-acute stage of recovery from traumatic brain injury. After controlling for pre-injury history of alcohol abuse, hospital admission blood alcohol level was predictive of poorer delayed verbal memory, greater decrement in verbal memory over time, and poorer visuospatial functioning. Moreover, there were non-significant trends for higher blood alcohol levels to predict poorer performance on measures of immediate verbal memory and perseveration.

Musculoskeletal stress due to sedentary work has been a problem in workplaces. Exercise programs are available to help alleviate such stress; however, they have been adopted by few companies. The acceptability of these problems, that is their "marketability" will be enhanced if employee preferences regarding exercise in the workplace are taken into account during their design. A questionnaire was administered to employees engaged in sedentary work to determine employees' preferences about exercise programs in the workplace. Respondents preferred exercises that are targeted for specific body parts, have easy-to-follow instructions, are somewhat difficult but more beneficial, and can be completed in a private room. Marketability of exercise programs may be improved by focusing on these characteristics.

A neutral and basic amino acid transporter (NBAT) cloned from rat kidney was recently localized to enteroendocrine cells and enteric neurons. We used an antibody directed against a synthetic peptide representing a putative extracellular domain of NBAT to determine whether this transporter was also present in other endocrine and neural tissues, including rat adrenal gland, brainstem, and spinal cord. Abundant, highly granular labeling for NBAT was observed in the cytoplasm of chromaffin and ganglion cells in the adrenal medulla. A small population of intensely labeled varicose processes was also seen in both the cortex and the medulla of the adrenal gland. More numerous, intensely labeled varicose processes were detected in brainstem and spinal cord nuclei, including the locus coeruleus, rostral ventrolateral medulla, nuclei of the solitary tract, dorsal motor nucleus of the vagus, and intermediolateral cell column of the thoracic spinal cord. Significant perikaryal labeling for NBAT was only detected in brainstem and spinal cord following intraventricular colchicine treatment, which increased the number, distribution, and intensity of NBAT-immunolabeled cells. These NBAT-immunoreactive perikarya were most numerous in the locus coeruleus, rostral ventrolateral medulla, nuclei of the solitary tract, and raphe nuclei. Ultrastructural examination of the nuclei of the solitary tract of normal rats showed that NBAT was localized predominantly to axon terminals. Within these labeled terminals, NBAT was associated with large dense core vesicles and discrete segments of plasma membrane. The observed localization of NBAT suggests that this renal specific amino acid transporter subserves a role as a vesicular or plasmalemmal transporter in monoamine-containing cells, including chromaffin cells and autonomic neurons. © 1995 Wiley-Liss, Inc.

The terminal part of the inner medullary collecting duct exhibits a high degree of water permeability that is independent of increased intracellular cAMP and not accounted for by the activity of the known renal epithelial water channels CHIP28 (28-kDa channel-forming integral protein) and WCH-CD (collecting duct water channel protein). Starting with rat kidney papilla mRNA, reverse transcription PCR was performed with degenerate primers assuming that the putative channel would be a member of the major intrinsic protein (MIP) family of proteins. A cDNA fragment was identified and used to screen a rat kidney cDNA library. A 1.9-kb cDNA clone was isolated. The open reading frame of 876 bp coded for a protein of 292 amino acids (M(r), 31,431). Aquaporin 3 (AQP3; 31.4-kDa water channel protein) is a newly discovered member of the MIP family. Northern blot analysis showed a single transcript for AQP3 of approximately 1.9 kb present in the renal medulla, predominantly in the inner medulla. With in situ hybridization, abundant message was found in the cells of the medullary collecting ducts. Injection of the complementary RNA of AQP3 into Xenopus oocytes markedly increased the osmotic water permeability. This permeability had an energy of activation of 3.0 kcal/mol (1 cal = 4.184 J), it was fully blocked by 1 mM p-chloromercuriphenylsulfonate, and this inhibition was reversed by 5 mM dithiothreitol. cAMP did not increase this water permeability. AQP3 did not permit passage of monovalent ions (Na, K, Cl); however, it is slightly permeable to urea. The present study demonstrates the existence of an additional water channel, AQP3, in epithelial cells of the medullary collecting duct.

Previous studies have indicated that patients scheduled for orthognathic surgery tend to have lower maximum bite forces and exert lower forces during mastication. The effect of these deficits on masticatory performance have not been previously assessed. Masticatory performance was analyzed in four groups: male and female orthognathic surgery patients prior to presurgical orthodontics (n = 12 and 23), and male and female controls (n = 27 and 31). Mastication performance was analyzed by having the subjects chew 5-g pieces of carrot for 20 cycles and measuring the resulting median particle size with a standard sieve method. Masticatory performance showed the same trends as maximum bite force and masticatory forces: male controls had the best and patients the poorest masticatory performance. There was a weak correlation between masticatory performance and maximum bite force at the molar positions. Masticatory performance also weakly correlated to electromyographic signals during mastication of a constant bolus (gummy bears) for all muscles except the left posterior temporalis. Correlations were generally not present or were very weak between masticatory performance, estimated masticatory forces, and muscle efficiency, suggesting that muscle efficiency and forces generated during mastication are not the primary factors that determine masticatory performance. Other factors contributing to a person's ability to chew food might include occlusal relationships and mechanical advantage.

Expression cloning in Xenopus oocytes was used to identify a clone for a renal K channel. The clone, named ROMK2, was obtained from a cDNA library constructed in the plasmid vector pSPORT using size-selected poly(A)+ RNA from whole rat kidney. ROMK2 consists of 1,837 nucleotides, with an open reading frame of 1,116 bases predicted to code for a 372-amino acid peptide. The clone appears to be a splice variant of a recently reported K channel (ROMK1) from rat renal outer medulla (Ho, K.H., C.G. Nichols, W.J. Lederer, J. Lytton, P.M. Vassilev, M.V. Kanazirska, and S.C. Hebert. Nature Lond. 362: 31-37, 1993). Northern blot analysis indicates that ROMK2 is expressed in renal cortex, medulla, and papilla. Expression in other tissues appears to be much lower. The functional properties of the channel as measured in Xenopus oocytes indicate its close relationship to ROMK1 and more distant relationship to the inward rectifier K channel (IRK1) (Kubo, Y, T.J. Baldwin, Y. N. Jan, and L. Y. Jan. Nature Lond. 362: 127-133, 1993). The inward conductance of the channel is a saturable function of external K, with a half-maximal conductance at Rb > NH4 > Na, Li. The conductance to Rb was only one-half that to K. Extracellular Ba2+ and Cs+ blocked the channel in a voltage-dependent manner. The high sensitivity of Cs+ block to voltage is consistent with the channel's operating as a multi-ion pore. The channel was blocked by high concentrations (100 microM) of glibenclamide. It did not appear to be blocked by extracellular Na+ or tetraethyl-ammonium ion. Patch-clamp measurements indicated a single-channel conductance of 30 pS in the presence of 110 mM K and high open probability that was weakly dependent on voltage. This channel may be involved in maintaining the membrane potential of renal cells and/or mediating renal K secretion.

There has been relatively little study of masticatory forces in dentofacial deformity patients before orthognathic surgery. This study used a mathematical equation based on electromyographic activity (EMG) during mastication and forces obtained during isometric bites to estimate masticatory forces in 55 control subjects and 48 patients. Subjects chewed on a constant bolus while EMG recordings were made bilaterally from the superficial masseter, anterior temporalis, and posterior temporalis muscles. Unilateral isometric bite forces in the first molar position and simultaneous EMGs were recorded in these same subjects. Superficial masseter muscle activity and isometric bite forces were strongly correlated. The slope of masseter EMG versus isometric force was used to estimate the masticatory forces. Males were found to have significantly higher estimated masticatory forces than females.

A sodium-independent neutral and basic amino acid transporter (NBAT) from rat kidney was recently cloned and its amino acid sequence deduced. We used light and electron microscopic immunoperoxidase labeling to determine the cellular localization of NBAT in rat kidney and small intestine. The localization was carried out using site-directed antisera raised against synthetic peptides within NBAT. The most prominent localization of NBAT was in microvilli of epithelial cells lining renal proximal tubules. Microvilli of small intestinal epithelia were less frequently immunoreactive. Unexpectedly, the most intense labeling in the small intestine was seen within enteroendocrine cells and submucosal neurons. The neuronal labeling was highly localized within dense core vesicles in axon terminals apposed to the basal lamina near fenestrated blood vessels. These results support the proposal that NBAT plays a role in reabsorption of amino acids in renal tubules. In addition, they suggest that NBAT (or NBAT-like proteins) may have multiple functions in the small intestine, including luminal uptake of amino acids and vesicular uptake of related substrates into enteroendocrine cells and enteric neurons.

Components of the gamma-glutamyl cycle, including thiols, glutathione (GSH) and gamma-glutamyl transpeptidase (gamma-GT), were localized in the nasal mucosae of rats using histochemical and immunohistochemical methods. In olfactory mucosa, thiols were widely distributed, with intense staining in the mucociliary complex (MC), basal cells, acinar cells of Bowman's glands (BG), and olfactory nerve bundles, and with moderate staining in olfactory receptor neurons (ORNs). GSH was localized in MC, BG acinar cells, nerve bundles and, to a lesser extent, in ORNs. gamma-GT immunoreactivity was restricted to the MC and to basolateral and apical membranes of BG acinar and duct cells. The basolateral membrane of BG acinar cells, located in close association with blood vessels and connective tissue, showed granule-like immunoreactivity. In respiratory mucosa, all three compounds were localized in the MC and acinar cells of respiratory glands (RG). In the MC, gamma-GT immunoreactivity was associated primarily with brush borders of ciliated cells. Granular immunoreactivity was also apparent in the supranuclear region of RG acinar cells. These results demonstrate that components of the gamma-glutamyl cycle are localized in olfactory and respiratory glands, and that they are secreted into the mucus, where they may mediate perireceptor events such as detoxification and/or solubilization of air-borne xenobiotics, toxicants and odorants.

The expression of a renal Na(+)-Ca2+ exchanger by Xenopus oocytes has been investigated. Each oocyte was injected with 50 ng of poly(A)+ RNA from either rat or rabbit kidney or with an equivalent volume of water. Na(+)-Ca2+ exchange was determined 3 days after injection, by measuring Ca2+ uptake by oocytes in the presence or absence of an outwardly directed Na+ concentration gradient. To manipulate Na+ concentration gradients, oocytes were first loaded with Na+ in Ca(2+)-free medium containing 90 mM Na+ and nystatin. They were then exposed to medium containing 45Ca and either 90 mM or 0 Na+. Na(+)-free media contained (in mM) either 90 K+, 90 choline or 85 choline plus 5 K+. Oocytes injected with rat kidney poly(A)+ RNA showed a Na+ gradient-dependent Ca2+ uptake of 6.6 +/- 0.8 (SE, n = 5) pmol.oocyte-1.30 min-1. This is significantly higher than the value of 3.4 +/- 0.5 (SE, n = 5) pmol.oocyte-1.30 min-1 obtained in water-injected oocytes (P less than 0.001). Similar results were obtained using poly(A)+ RNA from rabbit kidney cortex. Neither 10 microM nifedipine nor 0.5 mM D 600 significantly affected this Ca2+ uptake. However, 90% of the Ca2+ uptake was inhibited in the presence of 0.1 mM La3+. The poly(A)+ RNA-induced Na(+)-Ca2+ exchange activity was stimulated by the presence of 5 mM K+ in the extracellular choline solution compared with choline alone. Fractionation experiments indicate that the rat kidney Na(+)-Ca2+ exchanger was encoded by poly(A)+ RNA of 3-4 kb.

1. Iannitti DA, Coburn NG, Somberg J, et al. Use of the round ligament of the liver to decrease pancreatic fistulas: A novel technique. J Am Coll Surg 2006;203:857–864. 2. Bouvet M, Gamagami RA, Gilpin EA, et al. Factors influencing survival after resection for periampullary neoplasms. Am J Surg 2000;180:13–17. 3. Gamagami RA, Bouvet M, Moossa AR. The optimum surgical treatment for pancreatic head adenocarcinoma: Total pancreatectomy vs. Whipple. Poster presentation, 51 annual Southwestern Surgical Congress, April 1999.

▴ Kobayashi S, Boggon TJ, Dayaram T, et al . EGFR mutation and resistance of non-small-lung cancer to gefitinib. N Engl J Med2005;352:786–92 [OpenUrl][1][CrossRef][2][PubMed][3][Web of Science][4] Epidermal growth factor receptor (EGFR) is frequently overexpressed and in an activated phosphorylated form in non-small-cell lung cancers (NSCLC). Response rates of 10–20% can be achieved with the use of anilinoquinazoline tyrosine kinase inhibitors targeted against EGFR although most patients eventually relapse. The majority of responsive tumours contain somatic mutations … [1]: {openurl}?query=rft.jtitle%253DNew%2BEngland%2BJournal%2Bof%2BMedicine%26rft.stitle%253DNEJM%26rft.issn%253D0028-4793%26rft.aulast%253DKobayashi%26rft.auinit1%253DS.%26rft.volume%253D352%26rft.issue%253D8%26rft.spage%253D786%26rft.epage%253D792%26rft.atitle%253DEGFR%2BMutation%2Band%2BResistance%2Bof%2BNon-Small-Cell%2BLung%2BCancer%2Bto%2BGefitinib%26rft_id%253Dinfo%253Adoi%252F10.1056%252FNEJMoa044238%26rft_id%253Dinfo%253Apmid%252F15728811%26rft.genre%253Darticle%26rft_val_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Ajournal%26ctx_ver%253DZ39.88-2004%26url_ver%253DZ39.88-2004%26url_ctx_fmt%253Dinfo%253Aofi%252Ffmt%253Akev%253Amtx%253Actx [2]: /lookup/external-ref?access_num=10.1056/NEJMoa044238&link_type=DOI [3]: /lookup/external-ref?access_num=15728811&link_type=MED&atom=%2Fthoraxjnl%2F60%2F5%2F417.atom [4]: /lookup/external-ref?access_num=000227147500008&link_type=ISI

The activities of γ-glutamyl transpeptidase and other enzymes of the γ-glutamyl cycle, a series of reactions that catalyzes the synthesis and utilization of glutathione, were studied in the rabbit retina. Histochemical studies demonstrated that γ-glutamyl transpeptidase is localized in the visual receptor cells and the retinal pigment epithelium. Rat and mouse retinas revealed similar localizations of transpeptidase. These findings are in accord with the view that γ-glutamyl transpeptidase is involved in the transport of amino acids between the retinal pigment epithelium and the avascular visual receptor cells.

To learn more about the metabolic and clinical significance of 5-oxoproline (pyroglutamate, pyrrolidone carboxylate), we investigated the blood plasma concentrations of 5-oxo- l -proline and 5-oxo- d -proline in normal individuals and in patients with renal failure. Normal plasma levels of total 5-oxoproline of 7–19 μ m (mean, 13.9 ± 4 μ m ) were found; about 10% of the total 5-oxoproline is of the d -configuration. Patients with renal failure had plasma levels of 5-oxo- l -proline that were about 3.5 times higher than normal, and 5-oxo- d -proline levels that were about 25 times higher than the normals. No significant differences were found between the results obtained on anephric patients and those on the other patients with renal failure. The findings, which are relevant to the role of the kidney in glutathione and amino acid metabolism, reflect the significant function of the kidney in the utilization of 5-oxo- l -proline by 5-oxo- l -prolinase and in the excretion of 5-oxo- d -proline.

Microvillus membranes from rat kidney, jejunum, and epididymis have been purified by the Ca precipitation method. The membranes exhibit enrichment in specific activities of gamma-glutamyl transpeptidase, aminopeptidase M, and a dipeptidase. The latter has been characterized and shown to be the principal activity responsible for the hydrolysis of S derivatives of Cys-Gly (including cystinyl-bis-glycine (Cys-bis-Gly) and 5-hydroxy-6-S-cysteinylglycyl-1-7,9-trans-11,14-cis-eicosatetraenoic acid (leukotriene D4)). A method is described for the simultaneous purification of papain-solubilized forms of the three enzymes from renal microvilli. Dipeptidase (Mr = 105,000) appears to be a zinc metalloprotein composed of two Mr = 50,000 subunits. The enzyme is severalfold more effective in the hydrolysis of dipeptides than aminopeptidase M. Dipeptidase, in contrast to aminopeptidase M, is inhibited by thiol compounds; Cys-Gly, in particular, is a potent inhibitor (Ki = 20 microM). The inhibition of dipeptidase by thiols has been employed to probe the relative significance of dipeptidase and aminopeptidase M in the metabolism of glutathione and its derivatives at the membrane surface.

Human hepatoma cell (Hep G2) gamma-glutamyl transpeptidase (gamma-GT), a 120 ka single-chain glycoprotein, is much larger than the expected precursor of the dimeric enzyme in other human tissues. However, the Hep G2 gamma-GT mRNA encodes a 63 kDa peptide, similar to that of rat gamma-GT mRNA product and to the predicted, unglycosylated precursor of the enzyme in human tissues. Translation in presence of dog pancreas microsomes results in processing of the 63 kDa to an 80 kDa core-glycosylated species which is subsequently cleaved to 58 and 22 kDa subunits resembling those in other human tissues. The unusually large Mr of gamma-GT in Hep G2 would thus seem to be due to further glycosylation and processing in the Golgi. A deficiency of the processing protease is the most likely reason for the persistence of the single-chain form of gamma-GT in Hep G2 cells.

The γ-glutamyl transpeptidase activity of the epididymis is much higher than that of the several other organs of the reproductive system of the male rat. The epididymal caput has much more activity than the epididymal cauda. Relatively low activity was found in spermatozoa. The enzyme is present in the epididymal fluid in a particulate form suggesting that it originates from membranes of epididymal epithelial cells. The epididymal caput exhibits high γ-glutamylcysteine synthetase activity indicating an active γ-glutamyl ycle in this tissue, which plays an important role in transport phenomena.