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1.
J Wound Care ; 26(11): 642-650, 2017 11 02.
Article in English | MEDLINE | ID: mdl-29131748

ABSTRACT

OBJECTIVE: Our aim was to assess the effectiveness of hydro-responsive wound dressing (HRWD) in debridement and wound bed preparation of a variety of acute and chronic wounds that presented with devitalised tissue needing removal so that healing may proceed. METHOD: This was a non-comparative evaluation of acute and chronic wounds that required debridement as part of their normal treatment regimen. Clinicians recorded wound changes including a subjective assessment level of devitalised tissue and wound bed preparation, presence of pain, wound status (e.g., wound size) and periwound skin condition. Data was also collected from clinicians and patients to provide information on clinical performance of the dressing. RESULTS: We recruited 100 patients with a variety of wound types into the study. Over 90% of the clinicians reported removal of devitalised tissue to enable a healing response in both chronic and acute wounds. Specifically, over the course of the evaluation period, levels of devitalised tissue (necrosis and slough) reduced from 85.5% to 26.3%, and this was accompanied by an increase in wound bed granulation from 12.0% to 33.7%. Correspondingly, there was a 40% reduction in wound area, hence a clinically relevant healing response was seen upon treatment with HRWD. It is also noteworthy that this patient population included a significant proportion of chronic wounds (51.4%) that showed no signs of wound progression within <4 weeks before study inclusion. Of these chronic wounds, 93% demonstrated wound progression upon treatment with HRWD. Despite reported pain levels being low pre- and post-dressing change, overall wound pain improved (reduced) in 48% of patients. Periwound skin condition showed a tendency towards improvement, and the fluid management capabilities of the HRWD was reported as good to excellent in the majority of cases. Wound infections were reduced by at least 60% over the evaluation period. A simple cost-effective analysis demonstrated significant savings using HRWD (£6.33) over current standard practice regimens of a four-step debridement process (£8.05), larval therapy (£306.39) and mechanical pad debridement (£11.46). CONCLUSION: HRWD was well tolerated and was demonstrated to be an efficient debridement tool providing rapid, effective and pain free debridement in a variety of wound types.


Subject(s)
Autolysis , Bandages , Debridement/methods , Wounds and Injuries/therapy , Aged , Aged, 80 and over , Cost-Benefit Analysis , Exudates and Transudates , Female , Humans , Male , Middle Aged , Re-Epithelialization , Scotland , Treatment Outcome , Wound Infection/prevention & control
2.
Ir Med J ; 106(3): 89-90, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23951983

ABSTRACT

Qutenza is a high potency capsaicin topical patch which has been recommended for the treatment of peripheral neuropathic pain. The aim of this study was to assess our selected patients' response to Qutenza application. All patients had their dynamic pain score recorded prior to application and were asked to fill in a standardised questionnaire for three months post application. Patients were also asked to document any changes to the character of their pain, changes in sleep, activities of daily living and mood as well as any changes to their medication usage. 21 patients had Qutenza applied in a 5 month period. 17 patients completed the questionnaire in a 5 month period. We found that the mean overall reduction in pain score at 3 months was 32.7%. 8 of our patients (47%) reported improved sleep, activities of daily living and mood. 6 patients (35%) reported a reduction in medication use, while 7 (41%) reported an improvement in the character of their pain.


Subject(s)
Analgesics/administration & dosage , Capsaicin/administration & dosage , Chronic Pain/drug therapy , Neuralgia/drug therapy , Transdermal Patch , Activities of Daily Living , Chronic Pain/diagnosis , Humans , Neuralgia/diagnosis , Pain Measurement , Sleep/drug effects , Surveys and Questionnaires , Treatment Outcome
3.
Clin Transplant ; 23(1): 63-73, 2009.
Article in English | MEDLINE | ID: mdl-19200217

ABSTRACT

INTRODUCTION: Antibody mediated rejection (AMR) is associated with a greater incidence of allograft loss because traditional approaches - pulse steroid or anti-lymphocyte antibodies are usually ineffective. This retrospective analysis documented the benefit of rituximab administration in addition to plasmapheresis (PP). METHODS: We retrospectively reviewed the data from 54 kidney transplant patients treated for AMR between 2001 and 2006, including 26 patients who received PP plus rituximab (Group A), versus 28 subjects who underwent PP without rituximab (Group B). Only patients whose serum IgG levels were below normal values received intravenous gamma globulin (IVIG). In addition to clinical and demographic variables we evaluated graft/patient survivals at two years post-diagnosis, Banff classification of rejections, serum creatinine and calculated GFR values at baseline, rejection, resolution as well as three, six, 12 and 24 months thereafter. RESULTS: The demographic features of the cohorts showed no significant differences. The two-year graft survival for patients treated with rituximab plus PP was 90%, significantly better than 60% in the PP cohort (p = 0.005). Upon multivariate analysis administration of rituximab was the most significant factor (>or= 0.009); whereas, IVIG also produced a useful effect (p = 0.05). Neither the mean (>or= 0.42) nor the slope (p = 0.25) of GFR values showed a significant difference among salvaged kidneys over 24 months after completion of AMR treatment. The rates and types of infectious complications at three and six months did not show significant differences or impact on graft survival. CONCLUSION: Addition of rituximab improved the outcomes of PP treatment of antibody mediated rejection episodes.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antineoplastic Agents/therapeutic use , Graft Rejection/drug therapy , Kidney Transplantation , Acute Disease , Adult , Antibodies, Monoclonal, Murine-Derived , Antigens, CD20/immunology , Antilymphocyte Serum/therapeutic use , Cohort Studies , Creatinine/blood , Female , Glomerular Filtration Rate , Graft Rejection/diagnosis , Graft Rejection/immunology , Graft Survival/drug effects , Humans , Immunoglobulin G/blood , Immunoglobulins, Intravenous/therapeutic use , Male , Plasmapheresis , Retrospective Studies , Rituximab , Survival Rate , Transplantation, Homologous , Treatment Outcome
4.
Transplant Proc ; 37(5): 2032-6, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15964331

ABSTRACT

INTRODUCTION: Kidney transplant patients with acute rejection episodes refractory to antilymphocyte preparations require aggressive treatment to salvage renal function and reduce the progression of chronic allograft nephropathy. PATIENTS AND METHODS: During a 6-month period, we administered Campath-1H as salvage therapy to five patients who had been previously treated with thymoglobulin and/or OKT3. In addition to measurements of the serum creatinine and BUN levels, we estimated creatinine clearance and glomerular filtration rates (GFR) using the Cockcroft-Gault and the MDRD equations at the time of initiation of therapy as well as at 2 weeks and 2 months thereafter. RESULT: Four of the five patients responded to Campath-1H therapy; kidney function improved to nearly the level before the rejection episode. The estimated creatinine clearance increased approximately threefold and the GFR approximately fourfold higher than the values before Campath-1H administration. The adverse events were mild and self-limited. CONCLUSION: Salvage of refractory acute rejection episodes may be possible in selected patients using Campath-1H.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antibodies, Neoplasm/therapeutic use , Graft Rejection/drug therapy , Immunosuppressive Agents/therapeutic use , Kidney Transplantation/immunology , Acute Disease , Adult , Alemtuzumab , Antibodies, Monoclonal, Humanized , Female , Glomerular Filtration Rate , Humans , Male , Treatment Outcome
5.
Eur J Med Res ; 10(2): 76-80, 2005 Feb 28.
Article in English | MEDLINE | ID: mdl-15817427

ABSTRACT

AIM: Endotoxin is known to be a primary initiator of sepsis and septic shock. Migration of immunocompetent cells due to chemotactic attraction plays a central role in the initiation of the immune response. Two major groups of chemokines can be distinguished: C-x-C chemokines like Interleukin-8 attract mainly neutrophils, C-C chemokines (e.g. RANTES) attract monocytes and T-cells. The aim of this study was to get further insight into chemokine profiles after a single endotoxin bolus in man. MATERIALS AND METHODS: We investigated the effect of systemically administered endotoxin (4ng/kg BW i.v.) in 8 healthy volunteers. Clinical data (heart rate, mean arterial pressure, temperature), serum levels of IL-8, and RANTES, as well as white blood cell count were obtained before and hourly for five hours after endotoxin administration. RESULTS: Heart rate and MAP showed significant changes (p<0.05) after 2-3 hours. All volunteers presented with low-grade fever after 2 hours. WBC was elevated 43% and 63% after 4 and 5 hours, respectively. Both chemokines were significantly different from baseline two hours after endotoxin challenge: While IL-8 was significantly increased RANTES serum levels were diminished. CONCLUSION: From our data we conclude that this endotoxin model was effective to mimic the clinical appearance of sepsis. Chemokines like IL-8 and RANTES are integrated in the early immune response to endotoxin challenge in man.


Subject(s)
Chemokine CCL5/blood , Endotoxins/administration & dosage , Interleukin-8/blood , Adult , Blood Pressure , Female , Heart Rate , Humans , Leukocyte Count , Male , Sepsis/diagnosis
6.
J Biol Chem ; 276(10): 7681-8, 2001 Mar 09.
Article in English | MEDLINE | ID: mdl-11113151

ABSTRACT

The heterogeneous nuclear ribonucleoprotein (hn- RNP) C proteins, among the most abundant pre-mRNA-binding proteins in the eukaryotic nucleus, have a single RNP motif RNA-binding domain. The RNA-binding domain (RBD) is comprised of approximately 80-100 amino acids, and its structure has been determined. However, relatively little is known about the role of specific amino acids of the RBD in the binding to RNA. We have devised a phage display-based screening method for the rapid identification of amino acids in hnRNP C1 that are essential for its binding to RNA. The identified mutants were further tested for binding to poly(U)-Sepharose, a substrate to which wild type hnRNP C1 binds with high affinity. We found both previously predicted, highly conserved residues as well as additional residues in the RBD to be essential for C1 RNA binding. We also identified three mutations in the leucine-rich C1-C1 interaction domain near the carboxyl terminus of the protein that both abolished C1 oligomerization and reduced RNA binding. These results demonstrate that although the RBD is the primary determinant of C1 RNA binding, residues in the C1-C1 interaction domain also influence the RNA binding activity of the protein. The experimental approach we described should be generally applicable for the screening and identification of amino acids that play a role in the binding of proteins to nucleic acid substrates.


Subject(s)
Heterogeneous-Nuclear Ribonucleoprotein Group C , Mutation , RNA-Binding Proteins/chemistry , RNA-Binding Proteins/genetics , Ribonucleoproteins/chemistry , Amino Acid Sequence , Conserved Sequence , DNA Mutational Analysis , Escherichia coli/metabolism , Heterogeneous-Nuclear Ribonucleoproteins , Humans , Leucine/chemistry , Leucine/metabolism , Ligands , Molecular Sequence Data , Mutagenesis, Site-Directed , Peptide Library , Protein Binding , Protein Structure, Secondary , Protein Structure, Tertiary , Ribonucleoproteins/metabolism , Sequence Homology, Amino Acid , Transcription, Genetic
7.
Mol Cell Biol ; 20(3): 883-91, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10629045

ABSTRACT

Guide RNAs (gRNAs) are small RNAs that provide specificity for uridine addition and deletion during mRNA editing in trypanosomes. Terminal uridylyl transferase (TUTase) adds uridines to pre-mRNAs during RNA editing and adds a poly(U) tail to the 3' end of gRNAs. The poly(U) tail may stabilize the association of gRNAs with cognate mRNA during editing. Both TUTase and gRNAs associate with two ribonucleoprotein complexes, I (19S) and II (35S to 40S). Complex II is believed to be the fully assembled active editing complex, since it contains pre-edited mRNA and enzymes thought necessary for editing. Purification of TUTase from mitochondrial extracts resulted in the identification of two chromatographically distinct TUTase activities. Stable single-uridine addition to different substrate RNAs is performed by the 19S complex, despite the presence of a uridine-specific 3' exonuclease within this complex. Multiple uridines are added to substrate RNAs by a 10S particle that may be an unstable subunit of complex I lacking the uridine-specific 3' exonuclease. Multiple uridines could be stably added onto gRNAs by complex I when the cognate mRNA is present. We propose a model in which the purine-rich region of the cognate mRNA protects the uridine tail from a uridine exonuclease activity that is present within the complex. To test this model, we have mutated the purine-rich region of the pre-mRNA to abolish base-pairing interaction with the poly(U) tail of the gRNA. This RNA fails to protect the uridine tail of the gRNA from exoribonucleolytic trimming and is consistent with a role for the purine-rich region of the mRNA in gRNA maturation.


Subject(s)
Mitochondria/metabolism , Poly U/genetics , RNA, Guide, Kinetoplastida/genetics , RNA, Messenger/genetics , RNA, Protozoan/genetics , Ribonucleoproteins/metabolism , Trypanosoma brucei brucei/genetics , Animals , Base Sequence , Molecular Sequence Data , RNA Editing , RNA Nucleotidyltransferases/metabolism , RNA Precursors/genetics , RNA Precursors/metabolism , RNA Processing, Post-Transcriptional , RNA, Guide, Kinetoplastida/chemistry , RNA, Protozoan/metabolism
8.
Nucleic Acids Res ; 27(21): 4128-34, 1999 Nov 01.
Article in English | MEDLINE | ID: mdl-10518602

ABSTRACT

The human immunodeficiency virus type-1 Rev protein induces the nuclear export of intron-containing viral mRNAs that harbor its binding site, the Rev response element (RRE). A leucine-rich region of Rev, the activation domain, is essential for function and has been shown to be a nuclear export signal (NES). Although Rev exports viral RNAs that resemble cellular mRNAs, competition studies performed using microinjected Xenopus laevis oocytes have previously indicated that Rev utilizes a non-mRNA export pathway. Here, we show that Rev is able to induce the export of both spliceable and non-spliceable RRE-containing pre-mRNAs and that this activity is not dependent on the location of the RRE within the RNA. Importantly, even RNA molecules of different classes, such as U3 snoRNA and U6 snRNA, which are retained in the nucleus by non-pre-mRNA mechanisms, are exported to the cytoplasm in response to Rev. Consistent with the notion that Rev-mediated export of RRE-containing RNA is mechanistically distinct from the export of processed cellular mRNA, a chimeric Rev protein in which its NES is replaced by the NES of hnRNP A1 does not induce the export of a Rev-responsive mRNA. Finally, we demonstrate that Rev/RRE-activated RNA export is, like other nuclear export pathways, linked to the Ran-GTPase cycle.


Subject(s)
Cell Nucleus/metabolism , Gene Products, rev/metabolism , Heterogeneous-Nuclear Ribonucleoprotein Group A-B , RNA/metabolism , ran GTP-Binding Protein/metabolism , Animals , Biological Transport , COS Cells , Consensus Sequence/genetics , Exons/genetics , Gene Products, rev/chemistry , Gene Products, rev/genetics , Gene Products, tat/genetics , HIV-1/genetics , Heterogeneous Nuclear Ribonucleoprotein A1 , Heterogeneous-Nuclear Ribonucleoproteins , Introns/genetics , Mutation , Oocytes/metabolism , RNA/genetics , RNA Precursors/genetics , RNA Precursors/metabolism , RNA Splicing/genetics , RNA, Small Nuclear/genetics , RNA, Small Nuclear/metabolism , RNA, Small Nucleolar/genetics , RNA, Small Nucleolar/metabolism , RNA-Binding Proteins/metabolism , Response Elements/genetics , Ribonucleoproteins/genetics , Xenopus laevis , ran GTP-Binding Protein/genetics , rev Gene Products, Human Immunodeficiency Virus , tat Gene Products, Human Immunodeficiency Virus
9.
EMBO J ; 17(21): 6368-76, 1998 Nov 02.
Article in English | MEDLINE | ID: mdl-9799244

ABSTRACT

Kinetoplastid RNA editing consists of the addition or deletion of uridines at specific sites within mitochondrial mRNAs. This unusual RNA processing event is catalyzed by a ribonucleoprotein (RNP) complex that includes editing site-specific endoribonuclease, RNA ligase and terminal uridylnucleotidyl transferase (Tutase) among its essential enzymatic activities. To identify the components of this RNP, monoclonal antibodies were raised against partially purified editing complexes. One antibody reacts with a mitochondrially located 45 kDa polypeptide (p45) which contains a conserved repetitive amino acid domain. p45 co-purifies with RNA ligase and Tutase in a large ( approximately 700 kDa) RNP, and anti-p45 antibody inhibits in vitro RNA editing. Thus, p45 is the first kinetoplastid RNA-editing-associated protein (REAP-1) that has been cloned and identified as a protein component of a functional editing complex.


Subject(s)
Protozoan Proteins/genetics , RNA Editing/genetics , RNA/genetics , Trypanosoma brucei brucei/genetics , Amino Acid Sequence , Animals , Base Sequence , Cloning, Molecular , Fluorescent Antibody Technique , Microscopy, Fluorescence , Molecular Sequence Data , Protozoan Proteins/chemistry , RNA Ligase (ATP)/genetics , RNA Nucleotidyltransferases/genetics , RNA, Mitochondrial , Recombinant Proteins/genetics , Ribonucleoproteins/chemistry , Ribonucleoproteins/genetics , Sequence Analysis, DNA
10.
Annu Rev Microbiol ; 52: 491-532, 1998.
Article in English | MEDLINE | ID: mdl-9891806

ABSTRACT

The nuclear export of intron-containing HIV-1 RNA is critically dependent on the activity of Rev, a virally encoded sequence-specific RNA-binding protein. Rev shuttles between the nucleus and the cytoplasm and harbors both a nuclear localization signal and a nuclear export signal. These essential peptide motifs have now been shown to function by accessing cellular signal-mediated pathways for nuclear import and nuclear export. HIV-1 Rev therefore represents an excellent system with which to study aspects of transport across the nuclear envelope.


Subject(s)
Carrier Proteins/physiology , Gene Products, rev/physiology , HIV-1/chemistry , Karyopherins , Receptors, Cytoplasmic and Nuclear , Alternative Splicing , Amino Acid Sequence , Carrier Proteins/analysis , Carrier Proteins/genetics , Carrier Proteins/metabolism , Cell Nucleus/metabolism , Gene Expression Regulation, Viral , Gene Products, rev/analysis , Gene Products, rev/genetics , Gene Products, rev/metabolism , HIV Infections/therapy , Humans , Molecular Sequence Data , RNA, Messenger/metabolism , RNA, Viral/chemistry , RNA, Viral/metabolism , Trans-Activators , rev Gene Products, Human Immunodeficiency Virus , Exportin 1 Protein
11.
Crit Care Med ; 25(10): 1700-6, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9377885

ABSTRACT

OBJECTIVE: To measure cerebral blood flow, cerebral metabolic rate for oxygen, cerebral oxygen delivery, and cerebral vascular resistance during experimental endotoxemia in volunteers. DESIGN: Experimental, prospective study. SETTING: University general clinical research center. SUBJECTS: Healthy volunteers (six male, four female, 30.1 +/- 1.9 yrs of age). INTERVENTIONS: Volunteers had radial, pulmonary arterial, and jugular venous bulb catheters inserted. All volunteers received a bolus of Escherichia coli endotoxin (4 ng/kg). Cerebral blood flow was measured, using the Kety-Schmidt technique. MEASUREMENTS AND MAIN RESULTS: Cerebral and systemic hemodynamics and oxygenation variables were measured at baseline and hourly for 5 hrs after endotoxin administration. A systemic hyperdynamic response characterized by an increase in body temperature (97.9 +/- 0.02, 100.2 +/- 0.02, and 99.7 +/- 0.02 degrees F [36.6 +/- 0.01, 37.9 +/- 0.1, and 37.6 +/- 0.1 degrees C] at baseline, 3, and 5 hrs, respectively), cardiac index (3.7 +/- 0.2, 6.2 +/- 0.2, and 5.7 +/- 0.2 L/min/m2 at baseline, 3, and 5 hrs), and heart rate (70 +/- 2.6, 96 +/- 2.6, and 93 +/- 2.9 beats/min at baseline, 3, and 5 hrs), and a decrease in mean arterial pressure (99.3 +/- 2.2, 84.4 +/- 2.8, and 84 +/- 3.4 mm Hg at baseline, 3, and 5 hrs) and systemic vascular resistance (1498 +/- 53, 788 +/- 37, 849 +/- 36 dyne.sec/cm5.m2 at baseline, 3, and 5 hrs) followed the endotoxin bolus. Cerebral blood flow (65.4 +/- 4.3, 57.7 +/- 3.1, and 58.6 +/- 3.0 mL/100 g/min at baseline, 3, and 5 hrs), cerebral oxygen delivery (11.6 +/- 0.7, 9.8 +/- 0.6, and 9.5 +/- 0.6 mL/100 g/min at baseline, 3, and 5 hrs), cerebral metabolic rate for oxygen (3.8 +/- 0.4, 3.3 +/- 0.3, and 3.0 +/- 0.3 mL/100 g/min at baseline, 3, and 5 hrs), and cerebral vascular resistance (1.4 +/- 0.2, 1.4 +/- 0.2, and 1.3 +/- 0.2 mm Hg/mL/100 g/min at baseline, 3, and 5 hrs) were unchanged throughout the 5-hr study period. Signs of cerebral dysfunction were not apparent, although the volunteers appeared drowsy during the latter part of the study. CONCLUSION: A dose of endotoxin sufficient to induce systemic vasodilation in healthy subjects does not influence cerebral blood flow or the cerebral metabolic rate for oxygen.


Subject(s)
Cerebrovascular Circulation/drug effects , Endotoxemia/physiopathology , Endotoxins/pharmacology , Escherichia coli , Adult , Analysis of Variance , Brain/drug effects , Brain/metabolism , Endotoxemia/metabolism , Endotoxins/administration & dosage , Female , Hemodynamics/drug effects , Humans , Male , Oxygen Consumption/drug effects , Prospective Studies , Time Factors
12.
Am J Physiol ; 273(1 Pt 2): R371-8, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9249574

ABSTRACT

The purpose of the present study was to characterize the acute changes in the insulin-like growth factor (IGF) system in humans after administration of endotoxin (lipopolysaccharide; LPS). Escherichia coli LPS (4 ng/kg) was injected intravenously into healthy adults, and serial blood samples were collected for the next 5 h; subjects injected with saline served as time-matched controls. LPS administration resulted in a gradual decrease in the total extractable IGF-I concentration, which was reduced by approximately 20% over the final 2 h of the experiment; levels of free IGF-I were not significantly altered. LPS also produced a marked but transient elevation in growth hormone (GH) concentration. IGF-binding protein (BP)-1 levels were elevated more than fivefold 2 h after LPS injection, and thereafter levels gradually returned toward baseline. IGFBP-2 concentration also increased after LPS injection, but the maximal increase (approximately 50% above basal) was observed during the final 2 h of the protocol. In contrast, IGFBP-3 levels did not vary over the period examined in response to LPS, and there was no apparent increase in number of BP-3 proteolytic fragments. Cortisol levels were increased early and remained two- to threefold above baseline throughout the protocol. No significant alterations in serum concentration of glucose or insulin were noted. LPS also produced an early elevation in tumor necrosis factor and a later increase in interleukin-6. These data indicate that the acute changes in the GH-IGF axis in humans in response to LPS are comparable with those observed in humans in other traumatic conditions and in animal models of endotoxemia and infection.


Subject(s)
Human Growth Hormone/blood , Insulin-Like Growth Factor Binding Protein 1/blood , Insulin-Like Growth Factor Binding Protein 2/blood , Insulin-Like Growth Factor Binding Protein 3/blood , Insulin-Like Growth Factor I/metabolism , Lipopolysaccharides/pharmacology , Adolescent , Adult , Blood Glucose/metabolism , Blood Pressure/drug effects , Endotoxins/administration & dosage , Endotoxins/pharmacology , Escherichia coli , Female , Heart Rate/drug effects , Humans , Injections, Intravenous , Insulin/blood , Leukocyte Count/drug effects , Lipopolysaccharides/administration & dosage , Male , Pulmonary Artery/drug effects , Pulmonary Artery/physiology , Time Factors , Vascular Resistance/drug effects
13.
Exp Cell Res ; 229(2): 261-6, 1996 Dec 15.
Article in English | MEDLINE | ID: mdl-8986607

ABSTRACT

Many nuclear proteins are imported into the cell nucleus by the "classical" nuclear localization signal (NLS)-mediated import pathway. In this pathway, a sequence rich in basic residues in the protein interacts with a heterodimeric complex termed importin and this, along with the GTPase Ran, mediates nuclear import of the NLS-bearing protein. The heterogeneous nuclear ribonucleoprotein (hnRNP) A1 protein contains a novel nuclear localization sequence, termed M9, that does not contain any clusters of basic residues. Very recently, we showed that M9 directs import into the nucleus by a novel protein import pathway distinct from the classical NLS pathway. A 90-kilodalton protein termed transportin was identified as a protein that specifically interacts with wild-type M9 but not transport-defective M9 mutants. Transportin and an ATP-regenerating system were found to be necessary and sufficient for import of M9-containing proteins in an in vitro import assay. In this report, we provide additional evidence that transportin can interact directly with M9-containing proteins and also show that it can mediate import of full-length hnRNP A1. In addition, Ran, or a Ran-binding protein, is identified as a second protein component of this novel nuclear import pathway. Transportin relatives from Saccharomyces cerevisiae which likely serve as additional nuclear transport receptors are described.


Subject(s)
Heterogeneous-Nuclear Ribonucleoprotein Group A-B , Nuclear Proteins/metabolism , Receptors, Cytoplasmic and Nuclear/metabolism , Amino Acid Sequence , Animals , Biological Transport, Active , GTP Phosphohydrolases/metabolism , HeLa Cells , Heterogeneous Nuclear Ribonucleoprotein A1 , Heterogeneous-Nuclear Ribonucleoproteins , Humans , In Vitro Techniques , Karyopherins , Models, Biological , Molecular Sequence Data , Nuclear Localization Signals , Nuclear Proteins/genetics , Rabbits , Receptors, Cytoplasmic and Nuclear/genetics , Ribonucleoproteins/metabolism , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Sequence Homology, Amino Acid , ran GTP-Binding Protein
14.
J Burn Care Rehabil ; 17(6 Pt 1): 491-6, 1996.
Article in English | MEDLINE | ID: mdl-8951535

ABSTRACT

Monocyte/T-cell interactions play a critical role in the systemic response to infection. Distinct patterns of cytokines are produced by two different types of T-helper cells (Th). Th1 cells secrete interleukin-2 (IL-2) and interferon-gamma (IFN-gamma), whereas Th2 cells produce IL-4, IL-5, IL-6, IL-10, and IL-13. In volunteers systemic endotoxin administration initiates many features of gram-negative sepsis including cytokine release, but the patterns (i.e., Th1/Th2 patterns) have not yet been studied. In this institutional review board-approved study we investigated the effect of an intravenous bolus of endotoxin from Escherichia coli (4 ng/kg body weight) on the Th1/Th2 response in four female and four male volunteers (mean age 27.1 +/- 0.8 years). Plasma cytokine levels for IL-2, IL-4, IL-10, IL-12, and IFN-gamma and heart rate, mean arterial pressure, temperature, white blood cell, and differential blood count were determined before and hourly for 5 hours after endotoxin administration. All volunteers had tachycardia, decreased mean arterial pressure, fever, and leukocytosis. IL-10 was significantly (p < 0.05) elevated (9.4 +/- 3.9 pg/ml vs 60.9 +/- 19.3 pg/ml) 3 hours after endotoxin was administered, whereas IL-2 levels were decreased (69 +/- 26 U/ml vs 30.6 +/- 14.9 U/ml). IL-4 and IFN-gamma were not detectable in plasma. No changes were seen in the plasma levels of IL-12. Systemic responses did not correlate with changes in cytokine levels. Cytokine patterns found in this study suggest that after low-dose endotoxin administration the T-cell immune response is shifted towards the Th2 cell type response. This early shift towards a Th2 cell response may contribute to the depressed cell-mediated immune response associated with sepsis.


Subject(s)
Awards and Prizes , Cytokines/analysis , Endotoxins/administration & dosage , Escherichia coli , Interferon-gamma/analysis , T-Lymphocytes, Helper-Inducer/drug effects , Adult , Cytokines/metabolism , Endotoxemia/metabolism , Endotoxemia/physiopathology , Enzyme-Linked Immunosorbent Assay , Female , Hemodynamics/drug effects , Hemodynamics/physiology , Humans , Interleukin-10/analysis , Interleukin-12/analysis , Interleukin-2/analysis , Interleukin-4/analysis , Male , Reference Values , T-Lymphocytes, Helper-Inducer/metabolism
16.
Cell ; 86(6): 985-94, 1996 Sep 20.
Article in English | MEDLINE | ID: mdl-8808633

ABSTRACT

Targeting of most nuclear proteins to the cell nucleus is initiated by interaction between the classical nuclear localization signals (NLSs) contained within them and the importin NLS receptor complex. We have recently delineated a novel 38 amino acid transport signal in the hnRNP A1 protein, termed M9, which confers bidirectional transport across the nuclear envelope. We show here that M9-mediated nuclear import occurs by a novel pathway that is independent of the well-characterized, importin-mediated classical NLS pathway. Additionally, we have identified a specific M9-interacting protein, termed transportin, which binds to wild-type M9 but not to transport-defective M9 mutants. Transportin is a 90 kDa protein, distantly related to importin beta, and we show that it mediates the nuclear import of M9-containing proteins. These findings demonstrate that there are at least two receptor-mediated nuclear protein import pathways. Furthermore, as hnRNP A1 likely participates in mRNA export, it raises the possibility that transportin is a mediator of this process as well.


Subject(s)
Heterogeneous-Nuclear Ribonucleoprotein Group A-B , Nuclear Proteins/metabolism , Receptors, Cytoplasmic and Nuclear/metabolism , Amino Acid Sequence , Animals , Biological Transport, Active , HeLa Cells , Heterogeneous Nuclear Ribonucleoprotein A1 , Heterogeneous-Nuclear Ribonucleoproteins , Humans , In Vitro Techniques , Molecular Sequence Data , Mutation , Nuclear Proteins/genetics , Protein Sorting Signals/genetics , Protein Sorting Signals/metabolism , RNA, Messenger/metabolism , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Ribonucleoproteins/genetics , Ribonucleoproteins/metabolism , Sequence Homology, Amino Acid , beta Karyopherins
18.
Anesth Analg ; 82(2): 269-77, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8561326

ABSTRACT

Cerebral oximeters based on near-infrared spectroscopy may provide a continuous, noninvasive assessment of cerebral oxygenation. We evaluated a prototype cerebral oximeter (Invos 3100; Somanetics, Troy, MI) in 22 conscious, healthy volunteers breathing hypoxic gas mixtures. Using the first 12 subjects (training group), we developed an algorithm based on the mathematic relationship that converts detected light from the field surveyed by the probe to cerebral hemoglobin oxygen saturation (CSfO2). To develop the algorithm, we correlated the oximeter result with the estimated combined brain hemoglobin oxygen saturation (CScombO2, where CScombO2 = SaO2 x 0.25 + SjO2 x 0.75 and SjO2 = jugular venous saturation). We then validated the algorithm in the remaining 10 volunteers (validation group). A close association (r2 = 0.798-0.987 for individuals in the training group and r2 = 0.794-0.992 for individuals in the validation group) existed between CSfO2 and CScombO2. We conclude that continuous monitoring with cerebral oximetry may accurately recognize decreasing cerebral hemoglobin oxygen saturation produced by systemic hypoxemia.


Subject(s)
Brain/blood supply , Oximetry , Oxygen/blood , Spectrophotometry, Infrared , Adult , Evaluation Studies as Topic , Female , Humans , Male , Monitoring, Physiologic , Predictive Value of Tests , Sensitivity and Specificity
19.
Anesth Analg ; 82(2): 278-87, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8561327

ABSTRACT

Near-infrared spectroscopy may allow continuous and noninvasive monitoring of regional brain hemoglobin oxygen saturation by measuring the differential absorption of infrared light by oxyhemoglobin and deoxyhemoglobin. We have previously examined the correlation between the spectroscopic signal generated by a prototype cerebral oximeter (Invos 3100; Somanetics, Troy, MI), and global brain hemoglobin oxygen saturation calculated from arterial and jugular venous bulb oxygen saturations. Because the technology does not distinguish between arterial and venous hemoglobin saturation, changes in the proportion of cerebral arterial and venous blood volume, which may result from changes in blood flow or venous distending pressure, may confound measurements. In eight conscious volunteers breathing hypoxic oxygen mixtures, we examined the influence of supine, 20 degrees Trendelenburg, and 20 degrees reverse Trendelenburg positions on the correlation of the spectroscopic measurement of cerebral oxygen saturation in the field assessed by the probe (CSfO2) and the calculated brain hemoglobin oxygen saturation (CScombO2), estimated as 0.25 x arterial saturation plus 0.75 x jugular venous bulb oxygen saturation. We found that changes in position did not influence the association between CSfO2 and CScombO2 (r2 = 0.69-0.885) during hypoxic challenge. In a second set of eight volunteers, we studied the influence of hypercapnia and hypocapnia and body position on the association between CSfO2 and CScombO2, and found that they were less well correlated (r2 = 0.366-0.976) in individual patients. Because changes in body position and Paco2 confound the relationship between CSfO2 and CScombO2, changes in CSfO2 can best be assessed if position and Paco2 are constant.


Subject(s)
Brain/blood supply , Oxyhemoglobins/analysis , Posture , Spectrophotometry, Infrared , Adult , Cerebral Arteries , Cerebral Veins , Female , Humans , Hypercapnia/blood , Hypoxia/blood , Male , Middle Aged , Oximetry
20.
Chromosoma ; 104(4): 260-73, 1995 Dec.
Article in English | MEDLINE | ID: mdl-8565702

ABSTRACT

Knowledge of intrachromosomal transpositions has until now been primarily cytological and has been limited to Drosophila and to humans, in both of which segmental shifts can be recognized by altered banding patterns. There has been little genetic information. In this study, we describe the genetic and cytogenetic properties of a transposition in Neurospora crassa. In Tp(IR-->IL)T54M94, a 20 map unit segment of linkage group I has been excised from its normal position and inserted near the centromere in the opposite arm, in inverted order. In crosses heterozygous for the transposition, about one-fifth of surviving progeny are duplications carrying the transposed segment in both positions. These result from crossing over in the interstitial region. There is no corresponding class of progeny duplicated for the interstitial segment. The duplication strains are barren in test crosses. A complementary deficiency class is represented by unpigmented, inviable ascospores. Extent of the duplication was determined by duplication-coverage tests. Orientation of the transposed segment was determined using Tp x Tp crosses heterozygous for markers inside and outside the transposed segment, and position of the insertion relative to the centromere was established using quasi-ordered half-tetrads from crosses x Spore killer. Quelling was observed in the primary transformants that were used to introduce a critical marker into the transposed segment by repeat-induced point mutation (RIP).


Subject(s)
Chromosomes, Fungal/genetics , Cytogenetics/methods , Neurospora crassa/genetics , Translocation, Genetic , Centromere/genetics , Chromosome Mapping , Crosses, Genetic , Gene Rearrangement , Genetic Linkage , Heterozygote , Meiosis , Models, Genetic , Recombination, Genetic
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