Immunotherapy for type 1 diabetes.

INTRODUCTION: Despite advances in technology including the development of more sophisticated methods of monitoring blood glucose and delivering insulin, many individuals with type 1 diabetes continue to experience significant challenges in optimizing glycaemic control. Alternative treatment approaches to insulin are required. Increasing efforts have focused on developing treatments aimed at targeting the underlying disease process to modulate the immune system, maximize beta cell function and enhance endogenous insulin production and action. SOURCES OF DATA: Literature searches with keywords 'Type 1 diabetes and immunotherapy', publications relating to clinical trials of immunotherapy in type 1 diabetes. AREAS OF AGREEMENT: Insulin therapy is insufficient to achieve optimal glycaemic control in many individuals with type 1 diabetes, and new treatment approaches are required. Studies have showed promising results for the use of immunotherapy as a means of delaying disease onset and progression. AREAS OF CONTROVERSY: The optimal way of identifying individuals most likely to benefit from immunotherapies. GROWING POINTS: A better understanding of the natural history of type 1 diabetes has made it possible to identify individuals who have developed autoimmunity but have not yet progressed to clinical diabetes, offering opportunities not only to develop treatments that delay disease progression, but prevent its development in the first place. A consensus on how to identify individuals who may benefit from immunotherapy to prevent disease onset is needed. AREAS TIMELY FOR DEVELOPING RESEARCH: The development of optimal strategies for preventing and delaying progression of type 1 diabetes, and monitoring the response to immunointervention.

Neutrophils and secondary infections in COVID-19 induced acute respiratory distress syndrome.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus is the cause of the current global pandemic and has affected more than 188 countries worldwide. Infection by the virus can have diverse clinical manifestations, with one of the most severe clinical manifestation being respiratory failure and the development of acute respiratory distress syndrome. Clinical manifestations of acute respiratory distress syndrome secondary to SARS-CoV-2 are also diverse with a lack of diagnostic tools to distinguish between primary viral infection and secondary bacterial infections. This was a single-centre, retrospective case-control study of bronchoalveolar lavage fluid cell counts, flow cytometry and culture results from mechanically ventilated patients with SARS-CoV-2 (COVID-19) pneumonia and acute respiratory distress syndrome. Neutrophils were the predominant cell type in bronchoalveolar fluid samples up to 2 weeks into mechanical ventilation. There also was a strong correlation between positive respiratory cultures and significant elevation in bronchoalveolar fluid neutrophil counts/percentages and serum C-reactive protein levels. Absolute levels of T cell subtypes correlated with reduced lung compliance measurements. Patients with SARS-CoV-2 and severe respiratory disease are at risk for secondary infections. In some COVID-19 patients, serum C-reactive protein and bronchoalveolar fluid neutrophils may be correlated with a secondary infection.

Molecular definition of distinct cytoskeletal structures involved in complement- and Fc receptor-mediated phagocytosis in macrophages.

It has long been known from the results of ultrastructural studies that complement- and immunoglobulin G (IgG)-opsonized particles are phagocytosed differently by macrophages (Kaplan. G. 1977. Scand. J. Immunol. 6:797-807). Complement-opsonized particles sink into the cell, whereas IgG-coated particles are engulfed by lamellipodia, which project from the cell surface. The molecular basis for these differences is unknown. We used indirect immunofluorescence and confocal microscopy to examine how cytoskeletal proteins associate with phagosomes containing complement-opsonized zymosan (COZ) particles or IgG beads in phorbol-myristateacetate-treated peritoneal macrophages. During ingestion of COZ, punctate structures rich in F-actin, vinculin, alpha-actinin, paxillin, and phosphotyrosine-containing proteins are distributed over the phagosome surface. These foci are detected beneath bound COZ within 30 s of warming the cells to 37 degrees C, and their formation requires active protein kinase C. By contrast, during Fc receptor-mediated phagocytosis, all proteins examined were uniformly distributed on or near the phagosome surface. Moreover, ingestion of IgG beads was blocked by tyrosine kinase inhibitors, whereas phagocytosis of COZ was not. Thus, the signals required for particle ingestion, and the arrangement of cytoskeletal proteins on the phagosome surface, vary depending upon which phagocytic receptor is engaged. Moreover, complement receptor (CR)-mediated internalization required intact microtubules and was accompanied by the accumulation of vesicles beneath the forming phagosome, suggesting that membrane trafficking plays a key role in CR-mediated phagocytosis.

Virulent strains of Helicobacter pylori demonstrate delayed phagocytosis and stimulate homotypic phagosome fusion in macrophages.

Helicobacter pylori colonizes the gastric epithelium of approximately 50% of the world's population and plays a causative role in the development of gastric and duodenal ulcers. H. pylori is phagocytosed by mononuclear phagocytes, but the internalized bacteria are not killed and the reasons for this host defense defect are unclear. We now show using immunofluorescence and electron microscopy that H. pylori employs an unusual mechanism to avoid phagocytic killing: delayed entry followed by homotypic phagosome fusion. Unopsonized type I H. pylori bound readily to macrophages and were internalized into actin-rich phagosomes after a lag of approximately 4 min. Although early (10 min) phagosomes contained single bacilli, H. pylori phagosomes coalesced over the next approximately 2 h. The resulting "megasomes" contained multiple viable organisms and were stable for 24 h. Phagosome-phagosome fusion required bacterial protein synthesis and intact host microtubules, and both chloramphenicol and nocodazole increased killing of intracellular H. pylori. Type II strains of H. pylori are less virulent and lack the cag pathogenicity island. In contrast to type I strains, type II H. pylori were rapidly ingested and killed by macrophages and did not stimulate megasome formation. Collectively, our data suggest that megasome formation is an important feature of H. pylori pathogenesis.

Cardiovascular and renal outcomes following percutaneous coronary intervention in a population with renal disease: a case-control study.

BACKGROUND: Patients with renal disease are less likely to undergo percutaneous coronary intervention (PCI) due to concerns about poor outcomes. AIM: We describe outcomes following PCI in individuals with chronic kidney disease (CKD), as compared with matched controls with comparable CKD who did not undergo PCI. We also identified factors predictive of poor outcomes following PCI amongst patients with CKD. DESIGN: Retrospective observational case-control study. METHODS: Cases were individuals with CKD (stages 1-5) undergoing PCI between 2008 and 2014. Controls were age, gender and creatinine-matched individuals not requiring PCI. We compared mortality between groups using Kaplan-Meier curves and Cox regression modelling. We assessed changes in serum creatinine using Wilcoxon Rank testing. We explored the relationship between biochemical and haematological measures (baseline creatinine, calcium, phosphate, calcium-phosphate product, parathyroid hormone, white cell count, haemoglobin, platelet count, c-reactive protein and total cholesterol) and post-PCI mortality, using logistic regression. RESULTS: We identified 144 cases and 144 controls. Mortality was significantly lower amongst cases compared with controls [hazard ratio 0.46 (95% confidence intervals 0.31, 0.69)]. PCI did not result in a significant change in renal function (P=0.52). Amongst cases, serum creatinine and calcium-phosphate product were predictors of mortality following PCI. CONCLUSION: Cases undergoing PCI had lower mortality, and PCI was not associated with accelerated CKD progression. On this data, PCI should not be deferred as a treatment option in patients with CKD. Serum creatinine and calcium-phosphate product predict mortality following PCI in this cohort, and may be useful in risk-stratifying patients with CKD being considered for PCI.

Analyzer-based imaging of spinal fusion in an animal model.

Analyzer-based imaging (ABI) utilizes synchrotron radiation sources to create collimated monochromatic x-rays. In addition to x-ray absorption, this technique uses refraction and scatter rejection to create images. ABI provides dramatically improved contrast over standard imaging techniques. Twenty-one adult male Wistar rats were divided into four experimental groups to undergo the following interventions: (1) non-injured control, (2) decortication alone, (3) decortication with iliac crest bone grafting and (4) decortication with iliac crest bone grafting and interspinous wiring. Surgical procedures were performed at the L5-6 level. Animals were killed at 2, 4 and 6 weeks after the intervention and the spine muscle blocks were excised. Specimens were assessed for the presence of fusion by (1) manual testing, (2) conventional absorption radiography and (3) ABI. ABI showed no evidence of bone fusion in groups 1 and 2 and showed solid or possibly solid fusion in subjects from groups 3 and 4 at 6 weeks. Metal artifacts were not present in any of the ABI images. Conventional absorption radiographs did not provide diagnostic quality imaging of either the graft material or fusion masses in any of the specimens in any of the groups. Synchrotron-based ABI represents a novel imaging technique which can be used to assess spinal fusion in a small animal model. ABI produces superior image quality when compared to conventional radiographs.

MARCKS regulates membrane ruffling and cell spreading.

The dynamic rearrangement of the actin cytoskeleton is fundamental to most biological processes including embryogenesis, morphogenesis, cell movement, wound healing and metastasis [1]. Membrane ruffling and reversible cell-substratum interactions underlie actin-driven cell movement. Protein kinase C (PKC) stimulates membrane ruffling and adhesion [2], but the mechanism by which this occurs is unknown. Myristoylated alaninerich C kinase substrate (MARCKS) is a PKC substrate that cycles on and off membranes by a mechanism termed the myristoyl-electrostatic switch [3-6]. While at the membrane, MARCKS binds to and sequesters acidic phospholipids including phosphatidyl-inositol-4,5-bisphosphate (PIP2) [7]. MARCKS also binds and cross-links filamentous actin, an activity which is regulated by PKC-dependent phosphorylation and calcium-calmodulin [3]. In this report, we demonstrate that expression, in fibroblasts, of MARCKS containing a mutation which abrogates the myristoyl-electrostatic switch prevents cell spreading. The MARCKS mutant arrests the cell during an early stage of spreading, characterized by profuse membrane blebbing, and prevents the formation of membrane ruffles and lamellae usually found at the leading edge of spreading cells. This defect in the regulation of the actin cytoskeleton is accompanied by a decrease in cell-substratum adhesion. Our results provide direct evidence that MARCKS and PKC regulate actin-dependent membrane ruffling and cell adhesion, perhaps via a PIP2-dependent mechanism.

Mechanisms of phagocytosis.

Recent advances in research on phagocytosis include a better appreciation of the cross-talk between phagocytic receptors, the definition of multiple signaling domains within these receptors, and a deeper understanding of the downstream effector pathways leading to actin polymerization and particle internalization. Phagosome maturation in macrophages proceeds via a series of membrane fusion and fission events, which modify the phagosome in small increments, and appears to be regulated, in part, by GTP-binding proteins and perhaps by protein kinase C. The isolation of dysphagic mutants of Dictyostelium discoideum presages the identification of new genes required for phagocytosis.

VAMP3 null mice display normal constitutive, insulin- and exercise-regulated vesicle trafficking.

To investigate the physiological function of the VAMP3 vesicle SNARE (v-SNARE) isoform in the regulation of GLUT4 vesicle trafficking, we generated homozygotic VAMP3 null mice by targeted gene disruption. The VAMP3 null mice had typical growth rate and weight gain, with normal maintenance of fasting serum glucose and insulin levels. Analysis of glucose disposal and insulin sensitivity demonstrated normal insulin and glucose tolerance, with no evidence for insulin resistance. Insulin stimulation of glucose uptake in isolated primary adipocytes was essentially the same for the wild-type and VAMP3 null mice. Similarly, insulin-, hypoxia-, and exercise-stimulated glucose uptake in isolated skeletal muscle did not differ significantly. In addition, other general membrane trafficking events including phagocytosis, pinocytosis, and transferrin receptor recycling were also found to be unaffected in the VAMP3 null mice. Taken together, these data demonstrate that VAMP3 function is not necessary for either regulated GLUT4 translocation or general constitutive membrane recycling.

A rapid selection for animal cell mutants with defective peroxisomes.

Chinese hamster ovary (CHO) cells take up and incorporate 9-(1'-pyrene)nonanol (P9OH) into phospholipids and neutral lipids. Exposure of P9OH-labeled cells to long wavelength ultraviolet (UV) light causes cell death, because excitation of the pyrene moiety generates reactive oxygen species. CHO mutant cells deficient in plasmalogen biosynthesis and peroxisome assembly (Zoeller, R.A. and Raetz, C.R.H. (1986) Proc. Natl. Acad. Sci. USA 83, 5170-5174) are much more resistant to P9OH/UV treatment than are wild-type cells. This phenotype is explained by a 7.5-fold reduction of P9OH incorporation into the ethanolamine-linked phospholipids in the mutant cells and 2.4- to 6-fold reduction of P9OH incorporation into all other phospholipids and triglycerides, suggesting a general defect in fatty alcohol metabolism. [U-14C]Hexadecanol incorporation into the phospholipids of the mutant cells is also impaired. In contrast, the fatty acid analog, 9-(1'-pyrene)nonanoic acid, is incorporated into cells two times more rapidly by the mutants than by the wild type. Resistance to P9OH/UV treatment affords a simple, new method for the selection of animal cell mutants defective in peroxisome biogenesis.

Intracellular niches for extracellular bacteria: lessons from Helicobacter pylori.

Helicobacter pylori colonizes the gastric epithelium of humans and plays a causative role in peptic ulcer disease and perhaps gastric cancer. H. pylori proliferates in the mucus layer over the epithelium and is not cleared by the host immune response. Although the mucus layer is the major reservoir of H. pylori in vivo, a growing body of evidence suggests that H. pylori can persist in multiple intracellular locales. Clinical isolates of H. pylori invade epithelial monolayers at least as well as Shigella. The intracellular organisms are cytotoxic, and bacterial microcolonies form on the exposed basement membrane. Both mononuclear phagocytes and neutrophils phagocytose unopsonized H. pylori. However, the internalized organisms are not killed efficiently and our recent data suggest that H. pylori disrupts phagosome maturation. Collectively, the data support the hypothesis that intracellular H. pylori represent a reservoir of organisms that contributes to bacterial persistence, host tissue damage, and treatment failure.

Interaction of hybridoma antibodies with normal and mutant forms of Escherichia coli recA protein.

We have prepared hybridomas which secrete antibodies against E. coli recA protein, by fusing spleen lymphocytes from immunized mice with P3X63-AG8 myeloma cells. This paper describes a preliminary survey of properties of antibody from a hybridoma population designated 156, which inhibits the strand pairing, strand assimilation, repressor cleavage, and DNA-dependent ATPase activities of recA protein. The 156 antibody consists of one or two species which have been tentatively identified as IgG2b. 156 Globulin reacts 4.6-fold more efficiently with denatured recA protein, and it reacts partially with the native tif-1, lexB30, recA44, and recA629 proteins, as well as with peptide fragments which are not common to all four proteins.

Proabsorptive effect of glycerol as a glucose substitute in oral rehydration solutions.

We hypothesized that glycerol, a readily diffusable hydrophilic substance, may effectively substitute for glucose and enhance intestinal water and sodium absorption in an oral rehydration solution (ORS). This was evaluated using a low osmolality (230-240 mOsm/kg) ORS containing 75 mmol/L sodium and a combination of glucose:glycerol (in mmol/L) 75:0, 50:25; 37.5:37.5, 25:50, 10:65, or 0:75 during 3-hour long in vivo rat jejunal perfusions. Water, sodium, potassium, glucose and glycerol absorption, and unidirectional fluid movement (J(in), J(eff)) were determined. Sodium and net water absorptions were maximal at glucose:glycerol ratios between 37.5:37.5 and 10:65 mmol/L. In the absence of glucose (0:75), absorption of water and electrolytes was lower than at any other concentration. The greater net rehydration seemed to be due to a higher J(in) as glycerol was increased up to 65 mmol/L. Potassium absorption followed a similar pattern. With 50 mmol/L glycerol and 25 mmol/L glucose, there was a marked expansion of the lamina propria extracellular space and increased intercellular expansion between enterocytes. These results indicate that glycerol may be an effective partial substitute for glucose in ready-to-use ORS by producing an improved rate of water and electrolyte absorption.

Perception of self and other in major depression.

Previous research on the nature of person perception in depression has been inconclusive. This investigation differs from earlier studies in that extensive free-response descriptions of other people and self were collected from patients with major depression and from nonpsychiatric control Ss. In comparison with control Ss, depressed patients described fewer positive aspects not only of self but also of parents and significant others and reported more negative aspects of these people. Cluster analysis (HICLAS) also showed that more cognitive differentiation of negative self-perceptions (negative self-complexity) was characteristic of clinical depression. In both control Ss and patients, a positive (or negative) view of self was highly correlated (.85 or more) with a positive (or negative) view of parents and significant others. These correlations were significantly stronger than those between self and less important others.

Self-complexity, self-evaluation, and depression: an examination of form and content within the self-schema.

Six studies examined the relationship between self-complexity and variables related to self-evaluation. Self-complexity was found to comprise two components: positive self-complexity and negative self-complexity. Positive self-complexity was sensitive to methodological factors, namely, variations in stimulus materials used for self-ratings. Negative self-complexity was relatively stable in the face of different rating stimuli and tasks and was related to trait measures of self-evaluation, psychic distress, and psychopathology. These findings were observed and replicated. Higher negative self-complexity was associated with increases in depression symptoms over time. Higher negative self-complexity also predicted a poorer prognosis and less complete recovery from depression in a clinical sample. Results are discussed in light of related research and possible social-cognitive mechanisms.

Direct comparison between protons and alpha-particles of the same LET: I. Irradiation methods and inactivation of asynchronous V79, HeLa and C3H 10T1/2 cells.

A direct comparison was carried out of the biological effectiveness of protons and alpha-particles of the same linear energy transfer (LET) under identical conditions with a variety of in vitro biological systems. Monolayers of mammalian cells were irradiated with accelerated beams of protons (1.2 and 1.4 MeV) and alpha-particles (30 and 35 MeV) corresponding to LETs of 23 and 20 keV microns-1 for each particle type. For V79-4 cells it was observed that the linear term of the dose-response for cell inactivation by protons was significantly greater than that for alpha-particles of the same LET. For HeLa and HeLa S3 cells, also, the linear term appeared to be greater for protons, but this was not observed with more limited data for C3H 10T1/2 cells. The result for V79 cells is in agreement with the report of Belli et al. (1989) who observed that the biological effectiveness of protons rose sharply between 17 and 30 keV microns-1 in strong contrast to alpha-particles which reached a peak effectiveness at greater than 100 keV microns-1. These results place new constraints on the biologically relevant features of the microscopic structure of radiation tracks, and have implications for the mechanistic and practical comparison between radiations.

Cognitive behavior therapy for somatization disorder: a preliminary investigation.

Patients diagnosed with somatization disorder have high rates of disability and often prove refractory to treatment. This preliminary investigation examines the effect of a 10-session cognitive behavior therapy (CBT) protocol on the physical discomfort and disability of severely impaired somatizers. The severity of patients' physical discomfort and disability was assessed at baseline, post-treatment, and eight months following treatment. Patients reported significant improvement in symptomatology and physical functioning between baseline and post-treatment as well as between baseline and follow-up. The findings suggest that CBT might benefit patients diagnosed with somatization disorder and should be subjected to a controlled treatment trial.

The abused child as parent: the structure and content of physically abused mothers' perceptions of their babies.

OBJECTIVE: The major aim of the study was to provide an empirical answer to the following question: Does a mother's history of being physically abused as a child have a discernible impact on the structure and content of her perceptions and beliefs concerning her own child? METHOD: Free-response memories and current descriptions of babies, self, and significant others such as parents were compared longitudinally in two groups of mothers when their babies were 6 months, 1 year, and 2 years old. One group of mothers consisted of individuals who reported being physically abused as children; the control group consisted of mothers who were not physically abused. The two groups were comparable with respect to age of baby, race, and socioeconomic status. RESULTS: Abused mothers were found to differ significantly from control mothers in the structure and content of their free-response perceptions of their own babies. More specifically, abused mothers lagged behind controls in how well-differentiated were their negative perceptions of their babies. Differentiation in this study is operationally defined as the number of unique clusters that underlie a mother's perceptions of her baby, when social perception data is analyzed using cluster analysis (HICLAS). The greater the number of clusters observed, the greater is the differentiation. On the other hand, abused mothers were comparable to controls with respect to differentiation of positive perceptions of babies. CONCLUSIONS: The findings constitute a discovery about the structural organization of social cognition in mothers at-risk for child abuse. Implications of the findings for theory and future research are briefly discussed, as are limitations of the current study.

Museums, friends, and lovers in the New South: Laura's Web, 1909-1931.

Laura Bragg, a member of the first graduating class at Simmons College, journeyed to Charleston as a New Woman in 1909. As the first woman director of a major scientific museum in the United States, Bragg transformed the Charleston Museum into a public education institution and became an innovative leader in museum education. This article documents Bragg's contributions within the context of antebellum culture where the Southern Belle was placed on a Victorian pedestal and Boston marriages were an unknown phenomenon. Using extensive and hitherto unpublished correspondence, the authors detail Bragg's lesbian relationships and describe her network within the homosexual male community during the era of the Charleston Renaissance.