Tissue-resident memory T cell maintenance during antigen persistence requires both cognate antigen and interleukin-15

Our understanding of tissue-resident memory T (TRM) cell biology has been largely developed from acute infection models in which antigen is cleared and sterilizing immunity is achieved. Less is known about TRM cells in the context of chronic antigen persistence and inflammation. We investigated factors that underlie TRM maintenance in a kidney transplantation model in which TRM cells drive rejection. In contrast to acute infection, we found that TRM cells declined markedly in the absence of cognate antigen, antigen presentation, or antigen sensing by the T cells. Depletion of graft-infiltrating dendritic cells or interruption of antigen presentation after TRM cells were established was sufficient to disrupt TRM maintenance and reduce allograft pathology. Likewise, removal of IL-15 transpresentation or of the IL-15 receptor on T cells during TRM maintenance led to a decline in TRM cells, and IL-15 receptor blockade prevented chronic rejection. Therefore, antigen and IL-15 presented by dendritic cells play nonredundant key roles in CD8 TRM cell maintenance in settings of antigen persistence and inflammation. These findings provide insights that could lead to improved treatment of chronic transplant rejection and autoimmunity.

New onset MDA-5 positive dermatomyositis and massive perivillous fibrin deposition in third trimester of pregnancy: A case report

We report a case of a 42-year-old woman (Gravida 1, Para 1) who presented in her third trimester of pregnancy with a photo distributed eruption and arthralgias and was subsequently diagnosed with dermatomyositis. She had an emergency Caesarean section at 34 weeks plus 6 days gestation due to decreased fetal movements and non-reassuring fetal heart rate. Her placenta was sent for histopathology and showed features of massive perivillous fibrin deposition. To our knowledge, this is the first case of MDA-5 positive dermatomyositis in pregnancy with a live delivery.

Prospective population-based cohort of inflammatory bowel disease in the biologics era: Disease course and predictors of severity

BACKGROUND AND AIM

We have previously found high incidence of inflammatory bowel disease (IBD) in Australia. A population-based registry was established to assess disease severity, frequency of complications, and prognostic factors.

METHODS

Incident cases were prospectively identified over 4 years. Early disease severity was assessed according to need for hospitalization and resective surgery and medication use.

RESULTS

We report on the early outcomes (median 18 months, range 12-60 months) for 252 patients comprising 146 with Crohn's disease (CD), 96 with ulcerative colitis (UC), and 10 IBD undifferentiated. Eighty-seven percent of CD patients had inflammatory disease at diagnosis, and this reduced to 73% at 5 years (n = 38). Immunomodulators were prescribed in 57% of CD patients and 19% with UC. A third of all CD patients were hospitalized, the majority (77%) in the first 12 months. Risk factors for hospitalization included penetrating, perianal, and ileocolonic disease (P < 0.05). Twenty-four percent of UC patients were hospitalized, most within the first 12 months. Intestinal resection rates were 13% at 1 year in CD and 26% at 5 years. Risk factors include penetrating and stricturing disease (P < 0.001) and ileal involvement (P < 0.05). Colectomy rates in UC were 2% and 13% at 1 and 5 years. High C-reactive protein (CRP) at diagnosis was associated with colectomy.

CONCLUSIONS

A high rate of inflammatory disease, frequent immunomodulator use in CD, and a low rate of surgery in both CD and UC were identified. In CD, ileal involvement and complex disease behavior are associated with a more severe disease course, while in UC a high CRP predicted this outcome.

A role for the urokinase-type plasminogen activator system in amyotrophic lateral sclerosis

There is substantial evidence, implicating extracellular matrix (ECM) regulating enzymes in the pathogenesis of motor neuron degeneration in amyotrophic lateral sclerosis (ALS). The most important ECM-degrading proteases are serine proteases (plasminogen activators, PA) and matrix metalloproteinases (MMPs). Since the role of MMPs in ALS has been addressed recently, we investigated the expression of the serine protease urokinase-type plasminogen activator (uPA) and its receptor in ALS. Employing rtPCR, zymography and immunohistochemistry we analyzed the expression of uPA and its receptor uPAR in spinal cord tissue of ALS cases and in the G93A SOD1 transgenic mouse. In the ventral horn of the spinal cord of ALS cases we found increased uPAR staining of motor neurons. In G93A mice, the expression profile of uPA and uPAR mRNA was significantly increased starting at the age of 90 days as compared to non-transgenic littermates. The uPA-dependent plasminogen activation in G93A mice at endstage increased markedly compared with controls and immunostaining of the spinal cord from G93A mice revealed increased uPAR immunostaining in neurons. To determine the functional role of uPA, we investigated the effect of intraperitoneal (i.p.) administration of the uPA inhibitor WX-340 (10 mg/kg), starting at the age of 30 days (n=18). Treatment with WX-340 prolonged (p<0.05) survival of the animals (135+/-2 vs. 126+/-3) as well as improving rotarod performance. Our experiments demonstrate that uPA and its receptor are expressed in ALS patients and in an animal model of ALS. Early inhibition with a synthetic uPA inhibitor prolonged the life of the transgenic animals. These findings indicate that the urokinase-type plasminogen activator system may play a role in the complex pathogenesis of ALS.

Evaluation of cerebrospinal fluid uPA, PAI-1, and soluble uPAR levels in HIV-infected patients

To evaluate the potential role of the uPAR/uPA/PAI-1 system in HIV-induced blood-brain-barrier (BBB) disruption, CSF uPA-dependent plasminogen activation (PdPA) was analyzed by casein zymography, and CSF protein levels of all three molecules were measured by ELISA. CSF uPAR, but not uPA, PAI-1, or PdPA levels was significantly increased in neurologically compromised HIV+ patients. Only individual patients with severe AIDS dementia complex had increased levels of uPA (but not PAI-1) which fell upon initiation of antiretroviral therapy. The levels of all three molecules did not correlate with the CSF to serum albumin ratio suggesting not an important role in HIV-induced BBB disruption.

The origin of organic matter in the Martian meteorite ALH84001

Stable carbon isotope measurements of the organic matter associated with the carbonate globules and the bulk matrix material in the ALH84001 Martian meteorite indicate that two distinct sources are present in the sample. The delta 13C values for the organic matter associated with the carbonate globules averaged -26% and is attributed to terrestrial contamination. In contrast, the delta 13C values for the organic matter associated with the bulk matrix material yielded a value of -15%. The only common sources of carbon on the Earth that yield similar delta 13C values, other then some diagenetically altered marine carbonates, are C4 plants. A delta 13C value of -15%, on the other hand, is consistent with a kerogen-like component, the most ubiquitous form of organic matter found in carbonaceous chondrites such as the Murchison meteorite. Examination of the carbonate globules and bulk matrix material using laser desorption mass spectrometry (LDMS) indicates the presence of a high molecular weight organic component which appears to be extraterrestrial in origin, possibly derived from the exogenous delivery, of meteoritic or cometary debris to the surface of Mars.

The origin of organic matter in the Martian meteorite ALH84001

Stable carbon isotope measurements of the organic matter associated with the carbonate globules and the bulk matrix material in the ALH84001 Martian meteorite indicate that two distinct sources are present in the sample. The delta 13C values for the organic matter associated with the carbonate globules averaged -26% and is attributed to terrestrial contamination. In contrast, the delta 13C values for the organic matter associated with the bulk matrix material yielded a value of -15%. The only common carbon sources on the Earth that yield similar delta 13C values, other then some diagenetically altered marine carbonates, are C4 plants. A delta 13C value of -15%, on the other hand, is consistent with a kerogen-like component, the most ubiquitous form of organic matter found in carbonaceous chondrites such as the Murchison meteorite. Examination of the carbonate globules and bulk matrix material using laser desorption mass spectrometry (LDMS) indicates the presence of a high molecular weight organic component which appears to be extraterrestrial in origin, possibly derived from the exogenous delivery of meteoritic or cometary debris to the surface of Mars.

Study of structure and function of recombinant pea root plastid porin by biophysical methods

Pea root plastid porin (Fischer et al. (1994) J. Biol. Chem. 269, 25754-25760), which belongs to the family of mitochondrial (eukaryotic) porins, was expressed in Escherichia coli in high amounts using the pQE expression system. The recombinant protein was reconstituted into lipid bilayer membranes, and its characteristic properties were compared to those of the native porin isolated from pea root plastids. No significant difference was found between the native and the recombinant form when the protein was preincubated in detergent and sterol. The recombinant porin seems to be a valuable model system for the study of eukaryotic porins by spectroscopic methods, in which high amounts of protein are needed. CD spectroscopy was performed to determine the secondary structure of the porin under different conditions. It was found to have a high degree of beta-sheet structure in the nonionic detergent Genapol X-80 and in lipid vesicles. The more polar detergent sodium dodecyl sulfate (SDS) induced a large amount of alpha-helix structure in the protein. Addition of sterol to the porin in Genapol buffer did not influence its secondary structure to any measurable extent, whereas it had a strong influence on channel forming activity in black lipid bilayers. First refolding experiments performed in decreasing urea concentrations are discussed together with the results of the other measurements with regard to protein folding and channel formation.

Isolation of mitochondrial porin of the fly Protophormia: porin modification by the pesticide CGA 140'408 studied in lipid bilayer membranes

Mitochondrial porin from the fly Protophormia was solubilized with detergent from whole mitochondria and purified by chromatography across a hydroxyapatite (HPT) column. The purified protein had an apparent molecular mass of about 30 kDa on SDS-PAGE. Partial sequencing of the protein confirmed that it is porin. When reconstituted in planar lipid bilayer membranes, porin formed ion-permeable channels with single-channel conductances of 2.4 and 4.5 nS in 1 M KCl. At low voltage, Protophormia porin displayed the properties of a general diffusion pore and had a small selectivity for anions over cations. At transmembrane potentials starting with about 20-30 mV, the channel switched in closed state, which is still ion-permeable. Our results suggest that Protophormia porin possesses functional properties similar to those of other mitochondrial porins. Porin was also isolated and purified from mitochondria, which were treated with the carbodiimide CGA 140'408 It represents the active derivative of diafenthiuron a new acaricide and insecticide. This carbodiimide labels both a F0-component of the inner membrane ATPase and outer membrane porin in a similar way as N,N'-dicyclohexylcarbodiimide (DCCD). Reconstitution experiments with the CGA 140'408-modified porin showed no significant effect of the modification on the single-channel conductance, suggesting that CGA 140'408 binds outside the channel. The voltage-dependence of the CGA 140'408-modified porin was changed with respect to the unmodified form. The closed configuration of the pesticide-modified channel was reached at smaller transmembrane potentials, suggesting a shift of the open to the closed state of Protophormia porin by pesticide binding. A possible contribution of this effect to the pesticide action is discussed.

The role of the N and C termini of recombinant Neurospora mitochondrial porin in channel formation and voltage-dependent gating

To investigate the role of the N and C termini in channel function and voltage-dependent gating of mitochondrial porin, we expressed wild-type and mutant porins from Neurospora crassa as His-tag fusion products in Escherichia coli. Large quantities of the proteins were purified by chromatography across a nickle-nitrilotriacetic acid-agarose column under denaturing conditions. The purified His-tagged wild-type protein could be functionally reconstituted in the presence of detergent and sterol and behaved in black lipid bilayer membranes indistinguishably from native porin isolated from Neurospora crassa mitochondria. Mutants of porin lacking part of the N terminus (DeltaN2-12porin, DeltaN3-20porin), part of the C terminus (DeltaC269-283porin), or both (DeltaN2-12/DeltaC269-283porin) also showed channel forming activity. The mutant porin lacking the C terminus had a smaller single channel conductance than the wild-type protein, but its other biophysical properties were identical. DeltaN2-12porin and DeltaN3-20porin formed noisy channels with decreased channel stability. These channels were still voltage-dependent. DeltaN2-12/DeltaC269-283porin lost channel stability and had altered gating characteristics. These results are discussed with respect to different models that have been proposed in the literature for the structure of mitochondrial porin channels.

The role of sterols in the functional reconstitution of water-soluble mitochondrial porins from plants

Water-soluble porins were prepared from native mitochondrial porins isolated from different plants (pea and corn). In the water-soluble form the porins have lost their channel-forming properties. The water-soluble porins were investigated for the influence of different sterols on their membrane activity and their channel-forming properties in lipid bilayer membranes. Our experiments demonstrated that the water-soluble porins regained channel forming activity when the protein was preincubated with different sterols in the presence of a detergent. The channels formed in lipid bilayer membranes after this procedure regain in many but not all cases the original properties of the native mitochondrial porins. Preincubation with other sterols led to a change in the single-channel conductance or to a complete loss of the voltage dependence. The sterols had also a strong influence on the channel-forming activity of the porins. Preincubation of water-soluble pea porin with the plant sterol beta-sitosterol resulted in a considerable higher channel-forming activity than with all the other sterols used for preincubation. The role of the sterols in the channel-forming complex is discussed.

Effect of anesthetic variables on dermatomal somatosensory-evoked potential monitoring in elective lumbar spinal surgery

We studied 108 adult cases of elective lumbar surgery using dermatomal somatosensory-evoked potential (DSEP) monitoring to evaluate its usefulness due to concern over potential neurologic injury during pedicle screw insertion. Both surgeons used all of the necessary precautions required during surgery so that DSEP monitoring was not the "primary," but rather a backup system for operative security. Quality tracings were obtained in 71% of cases; anesthetic difficulties being the major cause of poor monitoring. There were no neurological complications related to pedicle screw insertion. We found that DSEP monitoring was an excellent method to verify intraoperative neurological status, but required a high degree of cooperation between the anesthesiologists, monitoring technician, and surgeons. In today's cost-containment environment, its usefulness is subjected to the expertise of the spine surgeon and the hospital setting.

Opioid pharmacotherapy in the management of cancer pain: a survey of strategies used by pain physicians for the selection of analgesic drugs and routes of administration

BACKGROUND

This survey documents the strategies used by pain control physicians in the selection of opioid drugs and routes of administration in the management of inpatients referred to a cancer pain service.

METHODS

The following approaches were prospectively evaluated during the treatment of 100 consecutive inpatients: 1) the influence of the evaluation of the goals of care on decision making, 2) selection of opioid drugs, 3) indications for changing opioid drugs and the frequency with which this strategy is used, and 4) selection of route of administration.

RESULTS

Eighty of the 100 patients underwent a total of 182 changes in drug, route, or both drug and route before discharge or death. The major reasons for change were to improve the convenience of treatment regimen in the setting of adequate pain relief (31.4%), diminish side effects in the setting of controlled pain (25.0%), reduce the invasiveness of therapy in the setting of controlled pain (19.3%), and simultaneously improve pain control and reduce opioid toxicity (17.7%). When opioid toxicity was the reason for change, physicians changed the opioid drug in 71% of cases and the route in 29%. When convenience or invasiveness were targeted, the physicians changed the route in 61% of cases and the opioid in 39%. Forty-four patients required one or more change in the opioid, and 20 required 2 or more changes (range, 2-6 changes). At the time of discharge (n = 82), morphine was more commonly selected than hydromorphone or fentanyl (39% vs. 23% vs. 17%) and the routes of administration were oral (57%), transdermal (18%), intravenous (18%), subcutaneous (5%), and intraspinal (4%). Therapeutic changes were associated with improvement in physician-recorded pain intensity and a lower prevalence of cognitive impairment, hallucinations, nausea and vomiting, and myoclonus among patients who were discharged from the hospital.

CONCLUSIONS

These data illustrate the application of strategies for selections of opioid drugs and their route of administration that are recommended in current guidelines for the management of cancer pain.

Role of sterols in the functional reconstitution of water-soluble mitochondrial porins from different organisms

Experiments were performed on lipid bilayer membranes with water-soluble mitochondrial porins from different eukaryotic organisms, such as Dictyostelium discoideum, Paramecium, and rat liver, to study the requirements of functional reconstitution of the porins. The water-soluble porins lost their associated lipids and sterols and are unable to form channels in lipid bilayer membranes. We demonstrate that the water-soluble porins regain their channel-forming ability after preincubation of the polypeptides with sterols in the presence of detergents. Mitochondrial porin from Dictyostelium discoideum maintained after this procedure its original properties, in particular the voltage dependence. Water-soluble mitochondrial porins from Paramecium tetraurelia and from rat liver were also activated upon preincubation with different sterols in detergent but showed voltage-dependences that were different from those of detergent-purified porins. Furthermore, the voltage dependence depended on the sterol used for preincubation. Interestingly, the preincubation with sterols can likewise be used to activate detergent-purified mitochondrial porins that may have lost associated sterol during isolation and purification procedures.

Porins from plants. Molecular cloning and functional characterization of two new members of the porin family

Porins are voltage-gated diffusion pores found in all eukaryotic kingdoms. Here we describe, for the first time, the identification and characterization of two cDNAs encoding porins from plants. Peptide sequences obtained from a 30-kDa protein of envelope membranes from pea root plastids allowed the isolation of two cDNA clones from pea and maize. On the protein level, both proteins are homologous by 58%. Sequence comparison against the Swiss-Prot sequence data base revealed a homology of about 25% to mitochondrial porins from fungi and human. Computer-aided predictions of the secondary structure of the plant porins revealed the presence of 16 antiparallel beta-strands that are also found in mitochondrial porins. Porins from non-green plastids and from the outer mitochondrial membrane were reconstituted into planar lipid bilayers. The proteins showed high pore-forming activities and similar single-channel conductances. In vitro translated porin was preferentially imported only into non-green plastids but not into chloroplasts. To our knowledge, this is the first example of selective import of a plastid protein into different types of plastids. This finding is in line with the observation that an immunoreactive 30-kDa band was only found in non-green plastids and mitochondria but not in chloroplasts. We conclude that mitochondria and non-green plastids possess homologous porin proteins, whereas chloroplasts are characterized by a different type of porin.

Association of anterior ectopic anus and partial absence of levator musculature in a woman with impaired defecation. Report of a case

A 25-year-old nulliparous woman with adult onset constipation and slight anterior displacement of the anus underwent pelvic magnetic resonance imaging and was diagnosed with congenital hemiabsence of the levator ani sling. Impaired defecation was confirmed by anorectal function studies and defecography demonstrated an anterior rectocele, perineal descent at the upper limit of normal, and partial obstruction of defecation, which appeared related to the levator sling abnormality. To our knowledge, this combination of findings has not been previously described as a cause of adult onset constipation.

Chemical and biochemical studies for the differentiation of coagulase-positive staphylococci

The cell wall composition, the configuration of lactic acid produced from glucose under anaerobic conditions, the occurrence of fructose-1,6-diphosphate (FDP) activated L-lactate dehydrogenase (L-LDH), and the esterase pattern were determined from more than 80 strains of coagulase-positive staphylococci isolated from man and animal. Strains isolated from man, swine, bovines and hares form a rather homogeneous group. They exhibit a similar cell wall composition, produce predominantly D,L-lactate and have a characteristic and simple esterase pattern. Coagulase-positive staphylococci isolated from dogs, horses, minks and pigeons are quite distinct from typical Staphylococcus aureus strains. They exhibit a different cell wall composition, produce only L-lactate, possess an L-LDH which is specifically activated by FDP, and have a quite complex esterase pattern.