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Kaposi's sarcoma (KS) is a multifocal systemic disease originating from vascular structures, associated with human type 8 herpesvirus and mainly affecting elderly men (male: female ratio, 10-15: 1)1,2 . Dermoscopy and reflectance confocal microscopy (RCM) are two non-invasive diagnostic methods that could improve the accuracy of KS detection2 - 4 . We carried out a review of the current English-language literature regarding dermoscopy and reflectance confocal microscopy as non-invasive diagnostic tools for Kaposi sarcoma lesions. Results are reported in Table 15 - 9 . Patients written informed consents were collected for images publication. Morphological variations of KS and its similarity with other angiomatous conditions often lead to difficulties to make a correct diagnosis only with clinical examination10 . Histological examination represents the gold standard for KS diagnosis3 . Dermoscopy and RCM are two non-invasive high- resolution techniques useful to add additional features in order to help clinicians making the correct diagnosis and also to address the choice for the biopsy-site4 .

SUMMARY Recombinant human type I collagen, identical in structure and functionality to human type I collagen, was successfully expressed and extracted from genetically modified tobacco plants. Contrarily to tissue extracted protein, rhCollagen is not immunogenic and not allergenic and has an intact triple helix structure showing superior biological functionality. A photocurable rhCollagen was developed by chemically modifying the protein to allow cross-linking under illumination at various wavelengths, maintaining the protein structural and biological functions. The use of the photocurable rhCollagen in aesthetic medicine, especially as a dermal filler and as a bioink for 3D-printed breast implant is discussed in this article.

A number of natural products with medicinal properties increase DNA cleavage mediated by type II topoisomerases. In an effort to identify additional natural compounds that affect the activity of human type II topoisomerases, a blind screen of a library of 341 Mediterranean plant extracts was conducted. Extracts from Nuphcir lutea, the yellow water lily, were identified in this screen. N. lutea has been used in traditional medicine by a variety of indigenous populations. The active compound in N. lutea, 6,6’-dihydroxythiobinupharidine, was found to enhance DNA cleavage mediated by human topoisomerase IIα and IIβ ~8-fold and ~3-fold, respectively. Mechanistic studies with topoisomerase IIα indicate that 6,6’-dihydroxythiobinupharidine is a “covalent poison” that acts by adducting the enzyme outside of the DNA cleavage-ligation active site and requires the N-terminal domain of the protein for its activity. Results suggest that some of the medicinal properties of N. lutea may result from the interactions between 6,6’-dihydroxythiobinupharidine and the human type II enzymes.

IL-17 family cytokines are critical to host defense responses at cutaneous and mucosal surfaces. Whereas IL-17A, IL-17F, and IL-17C induce overlapping inflammatory cascades to promote neutrophil-mediated immunity, IL-17E/IL-25 drives type 2 immune pathways and eosinophil activity. Genetic and pharmacological studies reveal the significant contribution these cytokines play in antimicrobial and autoimmune mechanisms. However, little is known about the related family member, IL-17B, with contrasting reports of both pro- and anti-inflammatory function in rodents. We demonstrate that in the human immune system, IL-17B is functionally similar to IL-25 and elicits type 2 cytokine secretion from innate type 2 lymphocytes, NKT, and CD4+ CRTH2+ Th2 cells. Like IL-25, this activity is dependent on the IL-17RA and IL-17RB receptor subunits. Furthermore, IL-17B can augment IL-33–driven type 2 responses. These data position IL-17B as a novel component in the regulation of human type 2 immunity.

The pathophysiology of type 1 diabetes is a complex process involving tightly controlled microenvironments, a number of highly specific immune cell - islet cell interactions, and the eventual breaking of immune tolerance leading to beta cell death. Modeling this process can provide researchers with powerful insights into how and when to best provide treatment, but has proven difficult to accurately model due to its complex nature and differences between animal models and humans. Much progress has been made in determining the genetic, molecular, and cellular mechanisms of type 1 diabetes, yet translating that knowledge to clinical treatments remains challenging. Thus, there exists a capabilities gap between understanding the disease pathophysiology and engineering effective clinical treatment strategies. Biomimetic modeling of human type 1 diabetes is a valuable tool to study and manipulate islet function and can be employed to address immunological aspects of type 1 diabetes. This article will review recent advances in this field, and will suggest ways to synergize systems to model and observe the pathophysiology of autoimmune diabetes with bioengineered therapeutic strategies.

Human type 2 innate lymphoid cells (ILC2) are the only ILC subset that shows heterogeneous expression of the SCF receptor c-Kit (CD117). Despite its use as surface marker to distinguish ILC populations, its influence on ILC2 biology has not been investigated. Here, we show that c-Kit expression of peripheral blood ILC distinguishes two functionally distinct ILC2 subsets (c-Kithi and c-Kitlo ). When examined for their potential for functional plasticity we found that c-Kitlo ILC2 displayed greater potential to produce type 2 cytokines, possibly representing fully mature and lineage committed ILC2. On the other hand, c-Kithi ILC2 coexpressed the ILC3-marker and chemokine receptor CCR6 and were able to mount a significant IL-17A response under ILC3-promoting conditions. In addition, c-Kithi ILC2 produced higher levels of IFN-γ than c-Kitlo ILC2 under ILC1-conditions. Although costimulation with SCF did not further influence ILC2 plasticity, it augmented type 2 cytokine production. We conclude that c-Kit marks distinct subpopulations of ILC2, which has therapeutic implications for conditions in which ILC2 are involved, such as allergy and asthma.

Exploring the accurate structure ensembles are critical to understand the functions of intrinsically disordered proteins (IDPs). As a well-known IDP, islet amyloid polypeptide (IAPP) plays important roles in the development of human type II diabetes (T2D). The toxicity of human IAPP (hIAPP) is induced by the amyloidosis of the peptide, however, its aggregation mechanism remains ambiguous. The characterization of structure ensemble of hIAPP, as well as the differences between hIAPP and its non-amyloidogenic homologous such as rat IAPP (rIAPP), would greatly help to illuminate the amyloidosis mechanism of IAPP. In this study, the atomic structure ensembles of hIAPP and rIAPP were characterized by all-atom molecular dynamics (MD) simulations combined with enhanced sampling technology and experiment data restraints. The obtained structure ensembles were firstly compared with those determined by the conventional MD (cMD) and enhanced sampling without experiment data restraints. The results showed that the enhanced sampling and experiment data restraints would improve the simulation accuracy. The transient N-terminal α-helix structures were adopted by the sub-states of both hIAPP and rIAPP, however, the C-terminal helical structures were only present on hIAPP. The hydrophobic residues in the amyloid-core region of hIAPP are exposed to the solvent. The structure ensemble differences between hIAPP and rIAPP revealed in this work provide potential explain to the amyloidogenic mechanism and would be helpful for the design of drugs to combat T2D.

Vastatin, a fragment derived from type VIII collagen, is one of the least studied collagen-derived matrikines. Vastatin can be detected in serum but little is known regarding the relevance of serum vastatin in colorectal cancer (CRC). In this study, serum vastatin was measured (ELISA) in 67 healthy controls and 48 CRC patients prior to resection and compared to clinicopathological parameters and serum biomarkers of stromal reactivity (C3M, VICM). Impact of resection and chemotherapy were evaluated by comparing baseline values with a 3-month follow-up sample (n = 23). Serum vastatin was detectable in 114 of 115 subjects. At baseline vastatin was elevated in CRC compared to controls (P

The H3N2 influenza viruses became widespread in humans during the 1968 H3N2 pandemic and have been a major cause of influenza epidemics ever since. Different lineages of H3N2 influenza viruses are also commonly found in animals. If a different lineage of H3N2 virus jumps to humans, a human influenza pandemic could occur with devastating consequences. Here, we studied the genetics, receptor-binding properties, and replication and transmission in mammals of 15 H3N2 avian influenza viruses detected in live poultry markets in China. We found that the H3N2 avian influenza viruses are complicated reassortants with distinct replication phenotypes in mice. Five viruses replicated efficiently in mice and bound to both human-type and avian-type receptors. These viruses transmitted efficiently to direct-contact guinea pigs, and three of them also transmitted among guinea pigs and ferrets via respiratory droplets. Moreover, ferret antiserum induced by human H3N2 viruses did not react with any of the H3N2 avian influenza viruses. Our study demonstrates that the H3N2 avian influenza viruses pose a clear threat to human health and emphasizes the need for continued surveillance and evaluation of the H3N2 influenza viruses circulating in nature.

In 2016 Delong et al. discovered a new type of neoepitope formed by the fusion of two unrelated peptide fragments. Remarkably these neoepitopes, called hybrid insulin peptides, or HIPs, are recognized by pathogenic CD4+ T cells in the NOD mouse and human pancreatic islet-infiltrating T cells in people with type 1 diabetes. Current data implicates CD4+ T-cell responses to HIPs in the immune pathogenesis of human T1D. Because of their role in the immune pathogenesis of human T1D it is important to identify new HIPs that are recognized by CD4+ T cells in people at risk of, or with, T1D. A detailed knowledge of T1D-associated HIPs will allow HIPs to be used in assays to monitor changes in T cell mediated beta-cell autoimmunity. They will also provide new targets for antigen-specific therapies for T1D. However, because HIPs are formed by the fusion of two unrelated peptides there are an enormous number of potential HIPs which makes it technically challenging to identify them. Here we review the discovery of HIPs, how they form and discuss approaches to identifying new HIPs relevant to the immune pathogenesis of human type 1 diabetes.

Since the establishment of the network for pancreatic organ donors with diabetes (nPOD), we have gained unprecedented insight into the pathology of human type 1 diabetes. Many of the pre-existing “dogmas”, mostly derived from studies of animal models and sometimes limited human samples, have to be revised now. For example, we have learned that autoreactive CD8 T cells are present even in healthy individuals within the exocrine pancreas. Furthermore, their “attraction” to islets probably relies on beta-cell intrinsic events, such as the over-expression of MHC class I and resulting presentation of autoantigens such as (prepro)insulin. In addition, we are discovering other signs of beta-cell dysfunction, possibly at least in part due to stress, such as the over-expression of certain cytokines. This review summarizes the latest developments focusing on cytokines and autoreactive CD8 T cells in human type 1 diabetes pathogenesis.

Bacterial type II phosphopantetheinyl transferases (PPTases), required for the activation of many cellular mega-synthases, have been validated as promising drug targets in several pathogens. Activation of the blue-pigment-synthesizing nonribosomal peptide synthetase BpsA by a target PPTase can be used to screen in vitro for new antibiotic candidates from chemical libraries. For a complete screening platform, there is a need to also counter-screen inhibitors for cross-reactivity with the endogenous human Type II PPTase (hPPTase), as this is a likely source of toxicity. As hPPTase is unable to recognize the PCP-domain of native BpsA, we used a combination of directed evolution and rational engineering to generate a triple-substitution variant that is able to be efficiently activated by hPPTase. Our engineered BpsA variant was able to readily detect inhibition of both hPPTase and the equivalent rat PPTase by broad-spectrum PPTase inhibitors, demonstrating its potential for high-throughput counter-screening of novel antibiotic candidates.

Summary Understanding the root causes of autoimmune diseases is hampered by the inability to access relevant human tissues and identify the time of disease onset. To examine the interaction of immune cells and their cellular targets in type 1 diabetes, we differentiated human induced pluripotent stem cells into pancreatic endocrine cells, including β cells. Here, we describe an in vitro platform that models features of human type 1 diabetes using stress-induced patient-derived endocrine cells and autologous immune cells. We demonstrate a cell-type-specific response by autologous immune cells against induced pluripotent stem cell-derived β cells, along with a reduced effect on α cells. This approach represents a path to developing disease models that use patient-derived cells to predict the outcome of an autoimmune response., Graphical Abstract, Highlights • β cell-specific response is achieved using iPSC-β cells and autologous immune cells • An in vitro immune response to iPSC-β cells requires ER stress • T cell activation is restricted to autologous iPSC-β cells • T cell activation is mediated by TCR engagement of peptide-HLA complexes on iPSC-β, Leite et al. describe an in vitro platform that models features of autoimmune type 1 diabetes using patient-derived endocrine cells and autologous immune cells. This represents a path to developing a model with patient-derived cells to predict and analyze the autoimmune response.

In vitro studies have shown that alterations in redox state can cause a range of opposing effects on the properties of the contractile apparatus in skeletal muscle fibers. To test whether and how redox changes occurring in vivo affect the contractile properties, vastus lateralis muscle fibers from seven healthy young adults were examined at rest (PRE) and following (POST) high-intensity intermittent cycling exercise. Individual mechanically skinned muscle fibers were exposed to heavily buffered solutions at progressively higher free [Ca(2+)] to determine their force-Ca(2+) relationship. Following acute exercise, Ca(2+) sensitivity was significantly decreased in type I fibers (by 0.06 pCa unit) but not in type II fibers (0.01 pCa unit). Specific force decreased after the exercise in type II fibers (−18%) but was unchanged in type I fibers. Treatment with the reducing agent dithiothreitol (DTT) caused a small decrease in Ca(2+)-sensitivity in type II fibers at PRE (by ∼0.014 pCa units) and a significantly larger decrease at POST (∼0.035 pCa units), indicating that the exercise had increased S-glutathionylation of fast troponin I. DTT treatment also increased specific force (by ∼4%), but only at POST. In contrast, DTT treatment had no effect on either parameter in type I fibers at either PRE or POST. In type I fibers, the decreased Ca(2+) sensitivity was not due to reversible oxidative changes and may have contributed to a decrease in power production during vigorous exercises. In type II fibers, exercise-induced redox changes help counter the decline in Ca(2+)-sensitivity while causing a small decline in maximum force. NEW & NOTEWORTHY This study identified important cellular changes occurring in human skeletal muscle fibers following high-intensity intermittent exercise: 1) a decrease in contractile apparatus Ca(2+) sensitivity in type I but not type II fibers, 2) a decrease in specific force only in type II muscle fibers, and 3) a redox-dependent increase in Ca(2+) sensitivity occurring only in type II fibers, which would help maintain muscle performance by countering the normal metabolite-induced decline in Ca(2+) sensitivity.

Helminth infections induce strong type 2 and regulatory responses, but the degree of heterogeneity of such cells is not well characterized. Using mass cytometry, we profiled these cells in Europeans and Indonesians not exposed to helminths and in Indonesians residing in rural areas infected with soil-transmitted helminths. To assign immune alteration to helminth infection, the profiling was performed before and 1 year after deworming. Very distinct signatures were found in Europeans and Indonesians, showing expanded frequencies of T helper 2 cells, particularly CD161+ cells and ILC2s in helminth-infected Indonesians, which was confirmed functionally through analysis of cytokine-producing cells. Besides ILC2s and CD4+ T cells, CD8+ T cells and γδ T cells in Indonesians produced type 2 cytokines. Regulatory T cells were also expanded in Indonesians, but only those expressing CTLA-4, and some coexpressed CD38, HLA-DR, ICOS, or CD161. CD11c+ B cells were found to be the main IL-10 producers among B cells in Indonesians, a subset that was almost absent in Europeans. A number of the distinct immune profiles were driven by helminths as the profiles reverted after clearance of helminth infections. Moreover, Indonesians with no helminth infections residing in an urban area showed immune profiles that resembled Europeans rather than rural Indonesians, which excludes a major role for ethnicity. Detailed insight into the human type 2 and regulatory networks could provide opportunities to target these cells for more precise interventions.

Type 1 diabetes is increasing in incidence in many parts of the world and it might be imagined that the pathological processes that underlie disease progression are firmly understood. However, this is not the case; rather, our collective understanding is still surprisingly rudimentary. There are various reasons for this but one of the most important is that the target organ (the pancreas) has been examined at, or soon after, diagnosis in only a small number of cases worldwide over the past half a century. This review provides a summary of some of the insights gained from these studies and highlights areas of ongoing uncertainty. In particular, it considers the process of insulitis (a form of islet inflammation that occurs characteristically in type 1 diabetes) and discusses the factors that may influence the access of immune cells to the beta cells. Attention is also drawn to recent evidence implying that two distinct profiles of insulitis exist, which occur differentially in people who develop type 1 diabetes at increasing ages. Emphasis is also placed on the emerging (and somewhat surprising) consensus that the extent of beta cell loss is variable among people with type 1 diabetes and that many (especially those who are older at onset) retain significant numbers of insulin-producing cells long after diagnosis. We conclude by emphasising the importance of renewed efforts to study the human pancreas at disease onset and consider how the current insights may inform the design of future strategies to slow or halt the rate of beta cell loss. Electronic supplementary material The online version of this article (10.1007/s00125-018-4731-y) contains a slideset of the figures for download, which is available to authorised users.

Binding exclusively to human-type receptors is a prerequisite for avian influenza viruses to transmit from human to human. We previously reported that 34% of H6 avian influenza viruses recognize the human-type receptor, but their affinity for the avian-type receptor remains higher than that for the human-type receptor. Here, we found that a single amino acid change from glutamine to leucine at position 226 of hemagglutinin caused a switch in receptor-binding preference from avian-type to human-type receptors and rendered A/chicken/Guangdong/S1312/2010(H6N2) capable of respiratory droplet transmission in guinea pigs.

Intranuclear rodlets (INRs) are rod-shaped intranuclear bodies of unknown function present in the nuclei of pancreatic beta cells. Previous studies have demonstrated a significant depletion of INRs from beta cells in mouse models of type II diabetes, suggesting that they may have pathological significance. The objective of the present study was to determine whether beta cell INRs show quantitative alterations in human type II diabetes. In sections of non-neoplastic pancreas from 23 diabetic patients and 23 controls who had undergone complete or partial pancreatectomy, we detected a significant reduction in the proportion of INRs in insulin-immunoreactive beta cells. In addition, we showed that beta cell INRs are immunoreactive for the RNA-binding protein HuR. The results of this study confirm and extend our previous study and implicate this enigmatic nuclear structure in the cellular pathophysiological mechanisms underlying the development of type II diabetes in humans.

Summary Liver fat content and the linked rate of export of triglyceride are central to the etiology of type 2 diabetes, as well as to the cardiovascular effects of fatty liver disease. Measurement in humans of intrahepatic and intrapancreatic fat content is described using magnetic resonance techniques and quantification of the rate of hepatic secretion of very low density lipoprotein using a non-isotopic competitive blocking of tissue uptake. This protocol is non-invasive, can be repeated sequentially, and does not involve ionizing radiation. For complete details on the use and execution of this protocol, please refer to (Taylor et al., 2018) and (Al-Mrabeh et al., 2020b)., Graphical Abstract, Highlights • Step-by-step description of intraorgan fat quantification in liver and pancreas • Description of in vivo measurement of hepatic lipoprotein triglyceride export • Application of novel magnetic resonance and lipoprotein turnover methods • Easy to reproduce methods without use of isotopes or ionization radiation, Liver fat content and the linked rate of export of triglyceride are central to the etiology of type 2 diabetes, as well as to the cardiovascular effects of fatty liver disease. Measurement in humans of intrahepatic and intrapancreatic fat content is described using magnetic resonance techniques and quantification of the rate of hepatic secretion of very low density lipoprotein using a non-isotopic competitive blocking of tissue uptake. This protocol is non-invasive, can be repeated sequentially, and does not involve ionizing radiation.

Altered myocardial fuel selection likely underlies cardiac disease risk in diabetes, affecting oxygen demand and myocardial metabolic flexibility. We investigated myocardial fuel selection and metabolic flexibility in human type 2 diabetes mellitus (T2DM), using positron emission tomography to measure rates of myocardial fatty acid oxidation {16-[18F]fluoro-4-thia-palmitate (FTP)} and myocardial perfusion and total oxidation ([11C]acetate). Participants underwent paired studies under fasting conditions, comparing 3-h insulin + glucose euglycemic clamp conditions (120 mU·m−2·min−1) to 3-h saline infusion. Lean controls ( n = 10) were compared with glycemically controlled volunteers with T2DM ( n = 8). Insulin augmented heart rate, blood pressure, and stroke index in both groups (all P < 0.01) and significantly increased myocardial oxygen consumption ( P = 0.04) and perfusion ( P = 0.01) in both groups. Insulin suppressed available nonesterified fatty acids ( P < 0.0001), but fatty acid concentrations were higher in T2DM under both conditions ( P < 0.001). Insulin-induced suppression of fatty acid oxidation was seen in both groups ( P < 0.0001). However, fatty acid oxidation rates were higher under both conditions in T2DM ( P = 0.003). Myocardial work efficiency was lower in T2DM ( P = 0.006) and decreased in both groups with the insulin-induced increase in work and shift in fuel utilization ( P = 0.01). Augmented fatty acid oxidation is present under baseline and insulin-treated conditions in T2DM, with impaired insulin-induced shifts away from fatty acid oxidation. This is accompanied by reduced work efficiency, possibly due to greater oxygen consumption with fatty acid metabolism. These observations suggest that improved fatty acid suppression, or reductions in myocardial fatty acid uptake and retention, could be therapeutic targets to improve myocardial ischemia tolerance in T2DM.

Protein arginine methyltransferases (PRMTs) play a crucial role in a variety of biological processes. Overexpression of PRMTs has been implicated in various human diseases including cancer. Consequently, selective small-molecule inhibitors of PRMTs have been pursued by both academia and the pharmaceutical industry as chemical tools for testing biological and therapeutic hypotheses. PRMTs are divided into three categories: type I PRMTs which catalyze mono- and asymmetric dimethylation of arginine residues, type II PRMTs which catalyze mono- and symmetric dimethylation of arginine residues, and type III PRMT which catalyzes only monomethylation of arginine residues. Here, we report the discovery of a potent, selective, and cell-active inhibitor of human type I PRMTs, MS023, and characterization of this inhibitor in a battery of biochemical, biophysical, and cellular assays. MS023 displayed high potency for type I PRMTs including PRMT1, -3, -4, -6, and -8 but was completely inactive against type II and type III PRMTs, protein lysine methyltransferases and DNA methyltransferases. A crystal structure of PRMT6 in complex with MS023 revealed that MS023 binds the substrate binding site. MS023 potently decreased cellular levels of histone arginine asymmetric dimethylation. It also reduced global levels of arginine asymmetric dimethylation and concurrently increased levels of arginine monomethylation and symmetric dimethylation in cells. We also developed MS094, a close analog of MS023, which was inactive in biochemical and cellular assays, as a negative control for chemical biology studies. MS023 and MS094 are useful chemical tools for investigating the role of type I PRMTs in health and disease.

Impaired activation of mitochondrial energy metabolism by glucose has been demonstrated in type 2 diabetic β-cells. The cause of this dysfunction is unknown. The aim of this study was to identify segments of energy metabolism with normal or with altered function in human type 2 diabetes mellitus. The mitochondrial membrane potential (ΔψM), and its response to glucose, is the main driver of mitochondrial ATP synthesis and is hence a central mediator of glucose-induced insulin secretion, but its quantitative determination in β-cells from human donors has not been attempted, due to limitations in assay technology. Here, novel fluorescence microscopic assays are exploited to quantify ΔψM and its response to glucose and other secretagogues in β-cells of dispersed pancreatic islet cells from 4 normal and 3 type 2 diabetic organ donors. Mitochondrial volume densities and the magnitude of ΔψM in low glucose were not consistently altered in diabetic β-cells. However, ΔψM was consistently less responsive to elevation of glucose concentration, whereas the decreased response was not observed with metabolizable secretagogue mixtures that feed directly into the tricarboxylic acid cycle. Single-cell analysis of the heterogeneous responses to metabolizable secretagogues indicated no dysfunction in relaying ΔψM hyperpolarization to plasma membrane potential depolarization in diabetic β-cells. ΔψM of diabetic β-cells was distinctly responsive to acute inhibition of ATP synthesis during glucose stimulation. It is concluded that the mechanistic deficit in glucose-induced insulin secretion and mitochondrial hyperpolarization of diabetic human β-cells is located upstream of the tricarboxylic acid cycle and manifests in dampening the control of ΔψM by glucose metabolism.

The concept of grouping Mendelian disorders associated with an up-regulation of type I interferon has only recently been suggested. Here we discuss the progress being made in the delineation and understanding of this novel set of inborn errors of immunity, the human type I interferonopathies.

Aims/hypothesis Pancreatic lymph nodes (PLNs) are critical sites for the initial interaction between islet autoantigens and autoreactive lymphocytes, but the histology of PLNs in tissue from individuals with type 1 diabetes has not been analysed in detail. The aim of this study was to examine PLN tissue sections from healthy donors compared with those at risk of, or with recent-onset and longer-duration type 1 diabetes. Methods Immunofluorescence staining was used to examine PLN sections from the following donor groups: non-diabetic (n=15), non-diabetic islet autoantibody-positive (n=5), recent-onset (≤1.5 years duration) type 1 diabetes (n=13), and longer-duration type 1 diabetes (n=15). Staining for CD3, CD20 and Ki67 was used to detect primary and secondary (germinal centre-containing) follicles and CD21 and CD35 to detect follicular dendritic cell networks. Results The frequency of secondary follicles was lower in the recent-onset type 1 diabetes group compared with the non-diabetic control group. The presence of insulitis (as evidence of ongoing beta cell destruction) and diagnosis of type 1 diabetes at a younger age, however, did not appear to be associated with a lower frequency of secondary follicles. A higher proportion of primary B cell follicles were observed to lack follicular dendritic cell networks in the recent-onset type 1 diabetes group. Conclusions/interpretation Histological analysis of rare PLNs from individuals with type 1 diabetes suggests a previously unrecognised phenotype comprising decreased primary B cell follicle frequency and fewer follicular dendritic cell networks in recent-onset type 1 diabetes.

Despite uncertainty of its exact role, muscle tension has shown an ability to alter human biomechanical response and may have the ability to reduce impact injury severity. The aim of this study was to examine the effects of muscle tension on human impact response in terms of force and energy absorbed and the subjects' perceptions of pain. Seven male martial artists had a 3.9 kg medicine ball dropped vertically from seven different heights, 1.0-1.6 m in equal increments, onto their right thigh. Subjects were instructed to either relax or tense the quadriceps via knee extension (≥60% MVC) prior to each impact. F-scan pressure insoles sampling at 500 Hz recorded impact force and video was recorded at 1000 Hz to determine energy loss from the medicine ball during impact. Across all impacts force was 11% higher, energy absorption was 15% lower and time to peak force was 11% lower whilst perceived impact intensity was significantly lower when tensed. Whether muscle is tensed or not had a significant and meaningful effect on perceived discomfort. However, it did not relate to impact force between conditions and so tensing may alter localised injury risk during human on human type impacts.

Taurine occurs in high concentrations in muscle and is implicated in numerous physiological processes, yet its effects on many aspects of contractility remain unclear. Using mechanically skinned segments of human vastus lateralis muscle fibers, we characterized the effects of taurine on sarcoplasmic reticulum (SR) Ca2+ accumulation and contractile apparatus properties in type I and type II fibers. Prolonged myoplasmic exposure (>10 min) to taurine substantially increased the rate of accumulation of Ca2+ by the SR in both fiber types, with no change in the maximum amount accumulated; no such effect was found with carnosine. SR Ca2+ accumulation was similar with 10 or 20 mM taurine, but was significantly slower at 5 mM taurine. Cytoplasmic taurine (20 mM) had no detectable effects on the responsiveness of the Ca2+ release channels in either fiber type. Taurine caused a small increase in Ca2+ sensitivity of the contractile apparatus in type I fibers, but type II fibers were unaffected; maximum Ca2+-activated force was unchanged in both cases. The effects of taurine on SR Ca2+ accumulation 1) only became apparent after prolonged cytoplasmic exposure, and 2) persisted for some minutes after complete removal of taurine from the cytoplasm, consistent with the hypothesis that the effects were due to an action of taurine from inside the SR. In summary, taurine potentiates the rate of SR Ca2+ uptake in both type I and type II human fibers, possibly via an action from within the SR lumen, with the degree of potentiation being significantly reduced at low physiological taurine levels.

The high prevalence of diabetes and diabetic complications has caused a huge burden on the modern society. Although scientific advances have led to effective strategies for preventing and treating diabetes over the past several decades, little progress has been made toward curing the disease or even getting it under control, from a public health and overall societal standpoint. There is still a lack of reliable biomarkers indicative of metabolic alterations associated with diabetes and different drug responses, highlighting the need for the development of early diagnostic and prognostic markers for diabetes and diabetic complications. The emergence of metabolomics has allowed researchers to systemically measure the small molecule metabolites, which are sensitive to the changes of both environmental and genetic factors and therefore, could be regarded as the link between genotypes and phenotypes. During the last decade, the progression made in metabolomics has provided insightful information on disease development and disease onset prediction. Recent studies using metabolomics approach coupled with statistical tools to predict incident diabetes revealed a number of metabolites that are significantly altered, including branched-chain and aromatic amino acids, such as isoleucine, leucine, valine, tyrosine and phenylalanine, as diagnostic or highly-significant predictors of future diabetes. This review summarizes the current findings of metabolomic studies in human investigations with the most common form of diabetes, type 2 diabetes.

Background Type 2 diabetes mellitus (T2DM) is a complex, pandemic disease contributing towards the global burden of health issues. To date, there are no simple clinical tests for the early detection of T2DM. Method To identify potential peptide biomarkers for such applications, 406 sera of T2DM patients (n = 206) and healthy controls (n = 200) were analyzed using MALDI-TOF MS with a cross-sectional case-control design. Result Six peptides (peaks m/z 1452.9, 1692.8, 1946.0, 2115.1, 2211.0 and 4053.6) were identified as candidate biomarkers for T2DM. A diagnostic model constructed with the 6 peptides was able to discriminate T2DM patients from healthy controls, with an accuracy of 82.20%, sensitivity of 82.50%, and specificity of 77.80% in the validation set. Peptide peaks m/z 1452.9 and 1692.8 were identified as fragments of the complement C3f, while peptide peaks m/z 1946.0, 2115.0, and 2211.0 were identified as the fragments of kininogen 1 isoform 1 precursor. Conclusion This study reinforces proteomic analyses as a potential technique for defining significant clinical peptide biomarkers, providing a simple and convenient diagnostic model for T2DM in clinical examination. This article is protected by copyright. All rights reserved

Nephropathy is among the most frequent complications of diabetes and the leading cause of end-stage renal disease. Despite the success of novel drugs in animal models, the majority of the subsequent clinical trials employing those drugs targeting diabetic nephropathy failed. This lack of translational value may in part be due to an inadequate comparability of human disease and animal models that often capture only a few aspects of disease. Here we overcome this limitation by developing a multimolecular noninvasive humanized readout of diabetic nephropathy based on urinary peptidomics. The disease-modified urinary peptides of 2 type 2 diabetic nephropathy mouse models were identified and compared with previously validated urinary peptide markers of diabetic nephropathy in humans to generate a classifier composed of 21 ortholog peptides. This classifier predicted the response to disease and treatment with inhibitors of the renin-angiotensin system in mice. The humanized classifier was significantly correlated with glomerular lesions. Using a human type 2 diabetic validation cohort of 207 patients, the classifier also distinguished between patients with and without diabetic nephropathy, and their response to renin-angiotensin system inhibition. Thus, a combination of multiple molecular features common to both human and murine disease could provide a significant change in translational drug discovery research in type 2 diabetic nephropathy.

Purpose To explore the safety and efficacy of PRT-201. Methods Randomized, double-blind, placebo-controlled, single-dose escalation study of PRT-201 (0.0033 to 9 mg) applied after arteriovenous fistula (AVF) creation. Participants were followed for one year. The primary outcome measure was safety. Efficacy measures were the proportion with intra-operative increases in AVF outflow vein diameter or blood flow ≥25% (primary), changes in outflow vein diameter and blood flow, AVF maturation and lumen stenosis by ultrasound criteria and AVF patency. Results The adverse events in the PRT-201 group (n=45) were similar to those in the placebo group (n=21). There were no differences in the proportion with ≥25% increase in vein diameter or blood flow, successful maturation or lumen stenosis. There was no statistically significant difference in primary patency between the dose groups (placebo n=21, Low Dose n=16, Medium Dose n=17 and High Dose n=12). In a subgroup analysis that excluded three participants with early surgical failures, the hazard ratio (HR) for primary patency loss of Low Dose compared with placebo was 0.38 (95% CI 0.10-1.41, P=0.15). In a Cox model, Low Dose (HR 0.27, 95% CI 0.04-0.79, P=0.09), white race (HR 0.17, 95% CI 0.03-0.79, P=0.02), and age Conclusions PRT-201 was not different from placebo for safety or efficacy measures. There was a suggestion for improved AVF primary patency with Low Dose PRT-201 that is now being studied in a larger clinical trial.

This work reports the isolation of Microgramma vaccinifolia rhizome lectin (MvRL) and the determination of electrochemical potentials of MvRL in the presence of Ca²⁺, Mg²⁺ and human type O erythrocytes. MvRL showed the highest specific hemagglutinating activity with human type O erythrocytes and showed a single polypeptide band of 17 kDa on SDS-PAGE. MvRL hemagglutinating activity was neutralized after dialysis with EDTA, and addition of Ca²⁺ and Mg²⁺ restored the activity. Electrochemical potentials of MvRL in the presence of 100 mM Ca²⁺ (882 mV) and 60 mM Mg²⁺ (1051 mV) were higher (p0.05) than in the presence of only 0.15 M NaCl (247 mV), indicating that the electrochemical system was sensitive to structural and physico-chemical changes promoted by these ions. MvRL potential did not change in the presence of type O erythrocytes. The electrochemical system was able to detect changes in electrochemical potentials of MvRL promoted by Ca²⁺ and Mg²⁺, even in a complex environment (human serum supplemented with 40 and 60mM of these ions). The study reveals that the stimulatory effect of Ca²⁺ and Mg²⁺ on hemagglutinating activity may be linked to conformational change and/or alterations in surface charge distribution of MvRL.

Summary Background Considering the high prevalence of dementia, it would be of great value to develop effective tools to improve cognitive function. We examined the effects of a human-type communication robot on cognitive function in elderly women living alone. Material/Methods In this study, 34 healthy elderly female volunteers living alone were randomized to living with either a communication robot or a control robot at home for 8 weeks. The shape, voice, and motion features of the communication robot resemble those of a 3-year-old boy, while the control robot was not designed to talk or nod. Before living with the robot and 4 and 8 weeks after living with the robot, experiments were conducted to evaluate a variety of cognitive functions as well as saliva cortisol, sleep, and subjective fatigue, motivation, and healing. Results The Mini-Mental State Examination score, judgement, and verbal memory function were improved after living with the communication robot; those functions were not altered with the control robot. In addition, the saliva cortisol level was decreased, nocturnal sleeping hours tended to increase, and difficulty in maintaining sleep tended to decrease with the communication robot, although alterations were not shown with the control. The proportions of the participants in whom effects on attenuation of fatigue, enhancement of motivation, and healing could be recognized were higher in the communication robot group relative to the control group. Conclusions This study demonstrates that living with a human-type communication robot may be effective for improving cognitive functions in elderly women living alone.

Re-addressing the 2013 consensus guidelines for the diagnosis of insulitis in human type 1 diabetes : is change necessary? Reply to Campbell-Thompson ML, Atkinson MA, Butler AE et al [letter].

Background Cultured dermal substitutes are used for the treatment of skin ulcers. However, the biological risks of fetal bovine serum (FBS) in the culture process have been reported. The use of the patient's autologous serum (AS) is another possibility, but the amount available is limited. In this study, we examined whether animal product-free media (HFDM-1) supplemented with 2% AS could support the growth of autologous fibroblasts in primary culture and their dissemination to dermal substitutes. Materials and Methods We cultured autologous fibroblasts using HFDM-1 with 2% AS, Dulbecco's modified eagle medium (DMEM) with 10% FBS, and DMEM with 10% human serum (HS). Then, we disseminated and cultured the cells for 10 d. The fibroblast proliferation and concentrations of vascular endothelial growth factor (VEGF) and transforming growth factor β1 (TGF-β1) in each medium, as well as the deposition of human type I collagen into dermal substitutes were examined. Results The number of fibroblasts cultured in HFDM-1 with AS was highest. After seeding, the number of fibroblasts cultured in DMEM with HS was higher than those in DMEM with FBS and HFDM-1 with AS, but no significant difference was found between these two media. The VEGF concentration in DMEM with HS was also larger, but no significant difference was found between two other media. No significant difference was observed in TGF-β1 concentration or the deposition of collagen. Conclusions This study shows that HFDM-1 with 2% AS can be used to produce cultured dermal substitutes instead of DMEM with 10% FBS.

In this research, we examined the effect on wound healing applying basic fibroblast growth factor (b-FGF) that is approved for clinical use to enhance wound healing and human deciduous teeth dental pulp cells (hDPCs) in clinics, but that have been attracting attention as a novel stem cell source in recent years. Human deciduous teeth were harvested from healthy volunteers, and hDPCs were isolated. We used a nude mouse full-thickness skin defect model and evaluated wound healing by macroscopic view and histologic and histomorphometric analysis. The mice were randomly divided into 4 groups: phosphate-buffered saline-treated group (control group), b-FGF-treated group (b-FGF group), hDPC-treated group (hDPC group), and hDPC and b-FGF-treated group (hDPC/b-FGF group). Basic fibroblast growth factor and hDPC groups accelerated wound healing compared with the control group. There was no statistically significant difference in wound healing observed between the hDPC and b-FGF groups. The hDPC/b-FGF group demonstrated accelerated wound healing compared with other groups. At day 14, PKH26-positive cells were surrounded by human type I collagen in hDPC and hDPC/b-FGF groups in immunohistologic evaluation. Significantly increased collagen fibril areas in wound tissues were observed in b-FGF, hDPC, and hDPC/b-FGF groups as compared with the control group at days 7 and 14. Our results showed that the hDPC/b-FGF group significantly promotes wound healing compared with other groups. This study implies that deciduous teeth that are currently considered as medical spare parts might offer a unique stem cell resource for potential of new cell therapies for wound healing in combination with b-FGF.

Type 1 diabetes (T1D) is considered a disorder whose pathogenesis is autoimmune in origin, a notion drawn in large part from studies of human pancreata performed as far back as the 1960s. While studies of the genetics, epidemiology, and peripheral immunity in T1D have been subject to widespread analysis over the ensuing decades, efforts to understand the disorder through analysis of human pancreata have been far more limited. We have reviewed the published literature pertaining to the pathology of the human pancreas throughout all stages in the natural history of T1D. This effort uncovered a series of findings that challenge many dogmas ascribed to T1D and revealed data suggesting the marked heterogeneity in terms of its pathology. An improved understanding and appreciation for pancreatic pathology in T1D could lead to improved disease classification, an understanding of why the disorder occurs, and better therapies for disease prevention and management.

Background: A new reference material for the liver enzyme aspartate transaminase (AST) (L-aspartate: 2-oxoglutarate-aminotransferase, EC 2.6.1.1), also called aspartate aminotransferase (ASAT), has been developed under the code ERM-AD457/IFCC. This certified reference material (CRM) for AST has been produced from a human type recombinant AST expressed in Escherichia coli and a buffer containing bovine serum albumin, and has been lyophilised. Methods: The homogeneity and the stability of the material have been tested and the catalytic activity concentration has been characterised by 12 laboratories using the reference procedure for AST at 37°C from the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC). Results: The certified catalytic activity concentration and certified uncertainty of AST in the reconstituted material are (1.74±0.05) μkat/L or (104.6±2.7) U/L (with a coverage factor k=2; 95% confidence interval). Conclusions: Both the certified value and uncertainty are traceable to the International System of Units (SI). The material is aiming to control the IFCC reference procedure for AST at 37°C, which will then be used to assign values to calibrants and control materials. The present paper highlights the scientific challenges and innovations which were encountered during the development of this new CRM. Clin Chem Lab Med 2010;48:795–803.

PURPOSE OF REVIEW Although studies of pancreata from type 1 diabetes (T1D) patients largely fell dormant for a period of decades, research efforts have recently been 'rekindled' in this area to address, using modern techniques, many unanswered questions related to the pathogenesis of this disease. RECENT FINDINGS As historically noted, a pancreatic infiltrate commonly referred to as 'insulitis' is present at the symptomatic onset of T1D. Recent studies have further characterized this infiltrate both in terms of its cellular composition as well as the mechanisms that likely underlie beta cell death in T1D. In addition, the notion that the pancreas from T1D patients is completely devoid of insulin producing cells years after the onset of disease has been challenged, whereas the concepts of whether beta cell regeneration or replication are present have also been subject to much debate. Novel concepts regarding the rate and degree of beta cell loss throughout the natural history of the disease have also been put forward to aid in explaining the disorder's pathogenesis. SUMMARY Although answers to many long-standing questions in T1D have recently been addressed, perhaps the main finding has been one supporting a disease of remarkable heterogeneity. However, additional lessons remain to be learned from the pancreas in T1D. Hence, attempts aimed at organizing the scientific community to address these issues are ongoing, particularly those from collaborative efforts, including the Belgium Organ Donor Consortium and the Network for Pancreatic Organ Donors with Diabetes (nPOD).

Human type 1 diabetes (T1D) is a chronic autoimmune disorder with complex genetic inheritance. To date, more than 19 insulin-dependent diabetes mellitus (IDDM) susceptibility loci have been mapped to specific chromosome regions in the human. MicroRNAs (miRNAs) are a recently discovered class of evolutionarily conserved small noncoding RNAs that negatively regulate the expression of protein-coding genes without affecting mRNA levels. There are a growing number of reports that miRNAs link to the regulation of different biological pathways associated with human diseases. However, the potential role of miRNAs in human T1D is still unknown. To investigate the possible involvements of miRNAs in human T1D on a genome-wide basis, we have mapped 530 miRNAs and compared their locations to the current IDDM loci. We found that at least 27 miRNAs are located in 9 human IDDM loci. More interestingly, some of them potentially target autoimmune- and beta-cell-related genes. Our data represent a genome-wide search for a potential correlation between the genomic position of miRNAs and specific IDDM loci, indicating that miRNAs may be susceptibility candidates or biomarkers for human T1D.

Purpose Collagen type II is the major component of cartilage and would be an optimal scaffold material for reconstruction of injured cartilage tissue. In this study, the feasibility of recombinant human type II collagen gel as a 3-dimensional culture system for bovine chondrocytes was evaluated in vitro. Methods Bovine chondrocytes (4x106 cells) were seeded within collagen gels and cultivated for up to 4 weeks. The gels were investigated with confocal microscopy, histology, and biochemical assays. Results Confocal microscopy revealed that the cells maintained their viability during the entire cultivation period. The chondrocytes were evenly distributed inside the gels, and the number of cells and the amount of the extracellular matrix increased during cultivation. The chondrocytes maintained their round phenotype during the 4-week cultivation period. The glycosaminoglycan levels of the tissue increased during the experiment. The relative levels of aggrecan and type II collagen mRNA measured with realtime polymerase chain reaction (PCR) showed an increase at 1 week. Conclusion Our results imply that recombinant human type II collagen is a promising biomaterial for cartilage tissue engineering, allowing homogeneous distribution in the gel and biosynthesis of extracellular matrix components.

Thoracic aortic dissections are associated with a significant risk of morbidity and mortality, and currently challenge our understanding of the biomechanical factors leading to their initiation and propagation. We quantified the biaxial mechanical properties of human type A dissections (n = 16) and modeled the stress–strain data using a microstructurally motivated form of strain energy function. Our results show significantly higher stiffness for dissected tissues as compared to control aorta without arterial disease. Higher stiffness of dissected tissues did not, however, correlate with greater aortic diameter measured prior to surgery nor were there any age dependent differences in the tissue properties.

Type 1 diabetes (T1D), a disorder of glucose homeostasis, is caused by autoimmune destruction of the essential insulin-secreting beta cells in the pancreas. Both genetic and environmental factors contribute to the risk of T1D and, for decades, this complexity has challenged investigators interested in identifying the genes that contribute to this risk. Nevertheless, in recent years, a number of well-supported T1D risk loci have been identified and replicated. Owing to development of more powerful study designs, the availability of dense marker maps, progress in high-throughput genotyping and a better basic understanding of the roles of genes in the immune system, this trend is likely to continue.

Insulin-like growth factor-1 (IGF-1) reportedly suppresses the development of type 1 diabetes in NOD mice, suggesting that IGF-1 is possibly a candidate for the autoantigens in type 1 diabetes. We therefore examined the anti-IGF-1 autoantibodies (IGF-1 Ab) in sera from patients with type 1 diabetes using radioimmunoassay. However, we were unable to demonstrate the existence of anti-IGF-1 autoantibodies in type 1 diabetes with our method. Further study is necessary to clarify whether anti-IGF-1 autoantibodies are existent in human type 1 diabetes and to determine the significance of IGF-1 in the pathogensesis of type 1 diabetes.

Oxidative stress is implicated in diabetes complications, during which endogenous antioxidant defenses have important pathophysiological consequences. To date, the significance of endogenous antioxidants such as metallothioneins I and II (MT-I+II) in type 2 diabetes remains unclear. To examine the MT-I+II-mediated antioxidant capacity and its response to exercise training in the skeletal muscle of patients with type 2 diabetes, biopsies and blood samples were taken from 13 matched subjects (type 2 diabetes n = 8, control subjects n = 5) both before and after 8 weeks of exercise training. Immunohistochemical analysis revealed reduced MT-I+II levels in the skeletal muscle of type 2 diabetic subjects compared with control subjects. Control subjects produced a robust increase of MT-I+II in response to training; however, in type 2 diabetes, MT-I+II levels remained essentially unchanged. Significantly lower levels of MT-I+II were also detected in the plasma of type 2 diabetic subjects compared with control subjects. These results suggest that, in control subjects, the MT-I+II defense system is active and inducible within skeletal muscle tissue and plasma. In type 2 diabetes, reduced levels of MT-I+II in muscle and plasma, as well as the deficient MT-I+II response to exercise, indicate that this antioxidant defense is impaired. This study presents a novel candidate in the pathogenesis of complications related to oxidative stress in type 2 diabetes.

The amount of type III collagen is increased during the early healing stage following ligament and tendon injury. Concomitantly, the mechanical properties of the healing tissues are abnormal and the fibril diameters are homogeneously small. It is therefore thought that downregulating type III collagen gene expression after injury may be helpful in improving the quality of healing tissue. In the current study, the efficacy of using antisense oligodeoxynucleotides (ODNs) to downregulate type III collagen gene expression in human patellar tendon fibroblasts (HPTFs) was tested, with Lipofectamine reagent used to deliver the ODN. It was shown that the majority of HPTFs can efficiently uptake antisense ODN from as early as 1 h to as long as 3 days after delivery; also, one selected ODN can consistently inhibit human type III collagen gene expression at both the mRNA and protein levels. Reverse transcriptase-polymerase chain reaction results showed that the inhibitory effects by this ODN were significant at 1 day, as the type III collagen mRNA level was 38.9 +/- 19.6 and 42.8 +/- 28.1% of missense and sense controls, respectively (p0.05). At 3 days, these differences could no longer be observed (p0.05), but the amount of type III collagen protein was significantly less than for missense and sense controls (31.7 +/- 5.5 and 25.3 +/- 5.3%, respectively; p0.05). At 5 days after the delivery, these differences in protein were no longer observed (p0.05). Immunohistochemical staining of the type III collagen confirmed these results. The findings of this study demonstrate that antisense ODN can downregulate type III collagen gene expression of tendon fibroblasts. Therefore, this approach offers the potential to explore the effect of the reduction of type III collagen in healing ligaments and tendons as a means to improve their mechanical properties.

Consensus definition of insulitis Patients with insulitis are defined by the presence of a predominantly lymphocytic infiltration specifically targeting the islets of Langerhans. The infiltrating cells may be found in the islet periphery (peri-insulitis), often showing a characteristic tight focal aggregation at one pole of the islet that is in direct contact with the peripheral islet cells. The infiltrate may also be diffuse and present throughout the islet parenchyma (intra-insulitis). The lesion mainly affects islets containing insulin-positive cells and is always accompanied by the presence of (pseudo)atrophic islets devoid of beta cells. The fraction of infiltrated islets is generally low (established in a minimum of three islets, with a threshold level of ? 15 CD45 + cells/islet before the diagnosis can be made. The pathology report should include the total num- ber of islets analysed, the fraction of islets affected by insulitis, the fraction of (pseudo)atrophic islets, and a de- scription of the spatial relationship of the infiltrate to the insulin-positive islet cells

To evaluate the effects of Aloe vera on gap junctional intercellular communication (GJIC) and proliferation of human skin fibroblasts in the presence or absence of basic fibroblast growth factor (FGF-2).In vitro study using human type II diabetic and nondiabetic skin fibroblast cell lines.Diabetic (n = 4) and nondiabetic (n = 4) human skin fibroblast cell lines were purchased from Coriell Institute for Medical Research (Camden, NJ). The cells were cultured with or without Aloe vera extract in increasing concentrations (0%, 0.625%, 1.25%, 2.5%, 5%, 10%, and 20%; v/v) in culture medium and with or without FGF-2 (30 ng/mL).GJIC was evaluated after 48-hour incubation with treatments by laser cytometry. Cells were counted after 72-hour incubation with treatments by using a Coulter counter.The rate of GJIC was greater (p0.01) for diabetic than for nondiabetic fibroblasts (3.5 +/- 0.1 versus 3.0 +/- 0.1% per minute during the first 4 minutes after photobleaching). GJIC was increased ( p0.05) for diabetic fibroblasts in the presence of 2.5% and 5% of Aloe vera extract (4.2 +/- 0.1 and 4.0 +/- 0.2 versus 3.5 +/- 0.1% per minute for control, respectively). FGF-2 stimulated (p0.01) GJIC for diabetic (4.0 +/- 0.1 versus 3.5 +/- 0.1% per minute for control) and nondiabetic (3.5 +/- 0.1 versus 3.0 +/- 0.1% per minute for control) fibroblasts. Aloe vera extract did not affect GJIC of nondiabetic fibroblast cultured without FGF-2. However, Aloe vera extract decreased (p0.05) FGF-2 stimulatory effects on GJIC of diabetic and nondiabetic fibroblasts. Proliferation of diabetic fibroblasts was increased (p0.05) by 1.25% and 2.5% Aloe vera extract in medium. Proliferation of nondiabetic fibroblasts was not affected by Aloe vera extract. FGF-2 increased (p0.05) proliferation of nondiabetic fibroblasts and FGF-2 did not affect proliferation of diabetic fibroblasts. Aloe vera extract decreased (p0.05) FGF-2 stimulatory effects on proliferation of nondiabetic fibroblasts.These data demonstrate that Aloe vera has the ability to stimulate GJIC and proliferation of human skin fibroblasts in diabetes mellitus. Furthermore, these results indicate that Aloe vera contains a compound(s) that neutralizes, binds with FGF-2 receptor, or otherwise alters signaling pathways for FGF-2. By affecting both GJIC and proliferation of diabetic fibroblasts, Aloe vera may improve wound healing in diabetes mellitus.