Diabetic Ketoalkalosis: A Common Yet Easily Overlooked Alkalemic Variant of Diabetic Ketoacidosis Associated with Mixed Acid-Base Disorders.

BACKGROUND: Diabetic ketoacidosis (DKA) is commonly complicated by mixed acid-base disorders. Therefore, patients with DKA can present with pH > 7.3 or bicarbonate > 18 mmol/L, which falls outside the values defined by the current traditional DKA criteria (pH ≤ 7.3 or bicarbonate ≤ 18 mmol/L). OBJECTIVE: We aimed to study the spectrum of acid-base clinical presentations of DKA and the prevalence of diabetic ketoalkalosis. METHODS: This study included all adult patients at a single institution admitted in 2018-2020 with diabetes, positive beta-hydroxybutyric acid, and increased anion gap ≥ 16 mmol/L. Mixed acid-base disorders were analyzed to determine the spectrum of presentation of DKA. RESULTS: There were 259 encounters identified under the inclusion criteria. Acid-base analysis was available in 227 cases. Traditional acidemic DKA (pH ≤ 7.3), DKA with mild acidemia (7.3 < pH ≤ 7.4), and diabetic ketoalkalosis (pH > 7.4) account for 48.9% (111/227), 27.8% (63/227), and 23.3% (53/227) of cases, respectively. Of the 53 cases with diabetic ketoalkalosis, increased anion gap metabolic acidosis was present in all, and concurrent metabolic alkalosis, respiratory alkalosis, and respiratory acidosis were present in 47.2% (25/53), 81.1% (43/53), and 11.3% (6/53) encounters, respectively. In addition, 34.0% (18/53) of those with diabetic ketoalkalosis were found to have severe ketoacidosis, defined by beta-hydroxybutyric acid ≥ 3 mmol/L. CONCLUSIONS: DKA can present as traditional acidemic DKA, DKA with mild acidemia, and diabetic ketoalkalosis. Diabetic ketoalkalosis is a common yet easily overlooked alkalemic variant of DKA associated with mixed acid-base disorders, and a high proportion of these presentations have severe ketoacidosis and thus, require the same treatment as traditional DKA.

Lung carcinoma paraneoplastic reactive regional pericarditis mimicking ST elevation myocardial infarct.

ST-elevation myocardial infarction (STEMI) is a cardiac emergency. However, multiple clinical disorders can cause ST-elevation ECG changes, one of which is pericarditis. Regional pericarditis is a less known clinical phenomenon that can mimic STEMI. We report a case of poorly differentiated lung carcinoma associated reactive regional pericarditis mimicking inferior STEMI.

Hypercalcemia of malignancy in metastatic esophageal squamous cell carcinoma with simultaneous PTHrP and calcitriol overproduction: A case report with literature review.

INTRODUCTION AND IMPORTANCE: hypercalcemia of malignancy is a severe complication of malignancy and associated with poor prognosis. Four mechanisms are implicated in this metabolic disorder, including excess parathyroid-related peptide secretion, focal osteolysis secondary to bone metastasis or multiple myeloma, excess calcitriol production, and ectopic parathyroid hormone production. Humoral hypercalcemia of malignancy secondary to isolated PTHrP or calcitriol overproduction is known; however, hypercalcemia of malignancy due to simultaneous PTHrP and calcitriol overproduction is less well known. CASE PRESENTATION: we report a case of a 63-year-old male who was diagnosed with poorly differentiated esophageal squamous cell carcinoma with simultaneous PTHrP and calcitriol overproduction. CLINICAL DISCUSSION: while hypercalcemia of malignancy secondary to simultaneous PTHrP and calcitriol secretion has been reported in other solid cancers, this is the first case of humoral hypercalcemia of malignancy secondary to simultaneous PTHrP and calcitriol secretion associated with esophageal cancer. This phenomenon deserves increased recognition as it has both diagnostic and therapeutic consequences. We discuss the current testing algorithm and its limitations in determining the etiology of hypercalcemia of malignancy since it may miss the diagnosis of simultaneous PTHrP and calcitriol production. CONCLUSION: we propose a revised testing algorithm for hypercalcemia of malignancy, which may improve the identification of simultaneous overproduction of PTHrP and calcitriol. This new algorithm can better characterize the mechanisms of hypercalcemia of malignancy and more appropriately guide treatment.

Pellagra, an Almost-Forgotten Differential Diagnosis of Chronic Diarrhea: More Prevalent Than We Think.

Pellagra, caused by vitamin B3 (niacin) deficiency, is traditionally described as dermatitis, diarrhea, dementia (3D), and even death (4D) syndrome if not recognized and treated promptly. Although full-blown pellagra with all 3D features has become rare, pellagra still exists, especially in high-risk populations, which is actually more prevalent than we think. We report that a recently treated patient with the full spectrum of 3D clinical features of pellagra presents as chronic diarrhea of unknown etiology for 1 year. It reminds us that keeping a high index of suspicion and maintaining a broad differential diagnosis are critical for recognition and management of this potentially fatal but treatable condition.

Prediabetes Directly Deteriorates into Diabetic Ketoacidosis and Hyperosmolar Hyperglycemic Syndrome Triggered by Acute Pancreatitis: A Case Report Illustrating a "Chicken and Egg" Paradigm in Ketosis-Prone Diabetes.

INTRODUCTION: Diabetic crises occur most often in patients with type 1 diabetes and occasionally in type 2 diabetes, especially under stressful conditions. However, a diabetic crisis occurring directly from prediabetes is an unusual phenomenon. CASE REPORT: A 45-year-old woman presented with postprandial left upper quadrant abdominal pain, nausea, and vomiting. She had a past medical history of prediabetes with impaired fasting glucose and HbA1c 6.4%. On admission, routine laboratory tests showed high anion gap metabolic acidosis (pH 6.92), anion gap 41 mmol/L, blood glucose 931 mg/dL, beta-hydroxybutyrate 28 mmol/L, and calculated effective osmolarity 322 mOsm/kg; she was diagnosed with diabetic ketoacidosis (DKA) and hyperosmolar hyperglycemic syndrome (HHS), and DKA-related abdominal pain. Later, the patient was found to have elevated lipase and amylase, and diagnosed with acute pancreatitis. Since DKA can induce abdominal pain and nonspecific lipase elevation, both of which are characteristics of acute pancreatitis, while acute pancreatitis can conversely trigger DKA, there exists a "chicken and egg" paradigm. Therefore, the differential diagnosis is discussed. CONCLUSION: It is important to differentiate DKA from concomitant causes of abdominal pain to avoid missing the underlying etiology, which can be the trigger for DKA. During diabetic crises, treating the underlying trigger is just as important as managing metabolic derangements in order to achieve favorable outcomes; meanwhile, managing acute pancreatitis-associated hyperglycemia can promote recovery. Additionally, diabetic crisis that directly evolves from prediabetes illustrates an atypical form of diabetes called ketosis-prone diabetes; we briefly discuss its clinical characteristics, classification, and follow-up.

Post-bariatric surgery starvation ketoacidosis and lipase elevation in the absence of DKA or pancreatitis.

We report a case of post bariatric surgery by laparoscopic sleeve gastrectomy who presented with post-surgical poor oral tolerance and high anion gap metabolic ketoacidosis, who was initially misdiagnosed with diabetic ketoacidosis and treated with volume supplementation without improvement. The metabolic derangements were found to be caused by starvation ketoacidosis, which was then treated with glucose supplementation, and the anion gap quickly closed. Moreover, this patient also presented with non-pancreatitis lipase elevation. This case highlights the recognition and management of post-bariatric surgery starvation ketoacidosis; additionally, clinicians should be vigilant about the interpretation and management of elevated lipase without clinical pancreatitis.

Bone marrow mesenchymal stem cells could acquire the phenotypes of epithelial cells and accelerate vaginal reconstruction combined with small intestinal submucosa.

Grafting material for vaginal reconstruction commonly includes the bowel, peritoneum, skin, and amniotic membrane. Bone marrow mesenchymal stem cells (MSCs) have the potential of multilineage differentiation into a variety of cells and have been widely explored in tissue engineering. In the current study, we examined whether MSCs could be differentiated to vaginal epithelial cells (VECs) upon co-culturing with VECs. We also examined whether Wnt/ß-catenin signaling pathway is implicated in such differentiation. Co-culture of MSCs with VECs using a transwell insert system (with no direct contact) induced the expression of VECs marker AE1/AE3 in MSCs. MSCs combined with small intestinal submucosa (SIS) scaffold were implanted in place of the native vagina in rats to observe the implications for vaginal reconstruction in vivo. Anatomic repair of neovagina was assessed by histological staining for H/E and Masson's Trichrome. GSK-3ß and ß-catenin, main members of Wnt/ß-catenin signaling pathway, in MSCs were increased upon co-culturing with VECs. Exposure of co-cultured MSCs to a Wnt/ß-catenin signaling activator, lithium chloride (LiCl, 20 µM) increased phosphorylated GSK-3ß and ß-catenin and enhanced expression of AE1/AE3. In vivo-grafted cells displayed significant matrix infiltration and expressed epithelial markers in neovagina. These findings suggest that MSCs could acquire the phenotype of VECs when co-cultured with VECs, possibly via activation of Wnt/ß-catenin signaling. MSCs provide an alternative cell source for potential use in vaginal tissue engineering.

The Th2 transcription factor c-Maf inhibits IL-12p35 gene expression in activated macrophages by targeting NF-kappaB nuclear translocation.

The inflammatory response of macrophages to infectious agents is a highly dynamic and orchestrated process involving the release of a variety of inflammatory mediators, including interleukin-12 (IL-12), as a consequence of the recognition of the pathogens. Regulation of IL-12 gene expression by the anti-inflammatory cytokine IL-10 represents a major homeostatic process underlying host-pathogen and host-self interactions. Our group first reported that the Th2-specific transcription factor c-Maf is expressed also in macrophages treated with lipopolysaccharide (LPS) and IL-10. When overexpressed, c-Maf can potently suppress IL-12 production. However, c-Maf does not appear to be a physiologic regulator of IL-12p40 gene transcription because p40 production is not dysregulated in c-Maf-deficient macrophages. In this study, we investigated the role of c-Maf in regulation of the transcription of the p35 gene, which encodes the chain that is rate limiting in the synthesis of the heterodimeric IL-12. We report that c-Maf is a physiologic modulator of IL-12p35 gene expression and IL-12p70 production. We identify a novel NF-kappaB element within the proximal p35 promoter and show that c-Maf inhibits p35 transcription by antagonizing the effects of NF-kappaB, especially c-Rel, on p35 activation. It does so not by directly interacting with the target DNA but by interfering with the nuclear localization of NF-kappaB c-Rel. This study contributes to our understanding of the molecular basis of the homeostatic regulation of IL-12 production by c-Maf, which plays a dual role both in the function of antigen-presenting cells (APCs) and in T helper cell differentiation.

NF-kappaB1 (p50) homodimers differentially regulate pro- and anti-inflammatory cytokines in macrophages.

NF-kappaB/Rel is a family of transcription factors whose activation has long been linked to the production of inflammatory cytokines. Here, we studied NF-kappaB signaling in the regulation of the anti-inflammatory cytokine, interleukin-10 (IL-10). We identified a role for a single NF-kappaB family member, NF-kappaB1 (p50), in promoting the transcription of IL-10. The NF-kappaB ciselement on IL-10 proximal promoter was located to -55/-46, where p50 can homodimerize and form a complex with the transcriptional co-activator CREB-binding protein to activate transcription. The other Rel family members appear to play a negligible role in IL-10 transcription. Mice lacking p50 were more susceptible to lethal endotoxemia, and macrophages taken from p50-/- mice exhibit skewed cytokine responses to lipopolysaccharide, characterized by decreased IL-10 and increased tumor necrosis factor and IL-12. Taken together, our studies demonstrate that NF-kappaB1 (p50) homodimers can be transcriptional activators of IL-10. The reciprocal regulation of pro- and anti-inflammatory cytokine production by NF-kappaB1 (p50) may provide potential new ways to manipulate the innate immune response.

The protooncogene c-Maf is an essential transcription factor for IL-10 gene expression in macrophages.

IL-10 is an important immunoregulatory factor. However, our understanding of IL-10 gene regulation remains very limited. In this study, following up on our previous novel finding that the protooncogene c-Maf of the basic leucine zipper family of transcription factors is expressed in monocytes and macrophages, we investigate the role of c-Maf in the transcriptional regulation of IL-10 and the underlying molecular mechanism in macrophages. c-Maf-null macrophages exhibit strongly impaired IL-10 protein production and mRNA expression upon LPS stimulation. Ectopic expression of c-Maf stimulates not only exogenously transfected IL-10 promoter-driven luciferase activity in a dose-dependent manner but also enhances endogenous IL-10 gene expression stimulated by LPS. Both in vitro and in vivo experiments identify a c-Maf response element localized to nucleotides -196/-184 relative to the transcription initiation site in the IL-10 promoter. This site represents an atypical 12-O-tetradecanoate-13-acetate-responsive element for musculoaponeurotic fibrosarcoma recognition and functions as an enhancer element in a heterologous and orientation-independent manner. Furthermore, c-Maf is expressed constitutively in resting monocytes/macrophages. IL-4 can up-regulate c-Maf expression, its binding to IL-10 promoter, and dose dependently enhance IL-10 production induced by LPS; moreover, IL-4 failed to enhance LPS-induced IL-10 production in c-Maf-null macrophages. Taken together, these data demonstrate that c-Maf is an indispensable yet constitutive transcription factor for IL-10 gene expression in LPS-activated macrophages, and IL-4 modulates IL-10 production in inflammatory macrophages likely via its ability to induce c-Maf expression. Thus, this study uncovers a novel and important function of c-Maf in macrophages and elucidates its transcriptional mechanism in the regulation of IL-10 gene expression.

Interleukin-12: an update on its immunological activities, signaling and regulation of gene expression.

Interleukin-12 (IL-12) is a heterodimeric cytokine composed of the p35 and p40 subunits. It is produced by antigen-presenting cells and plays a critical role in host defense against intracellular microbial infection and control of malignancy via its ability to stimulate both innate and adaptive immune effector cells. The potency of IL-12 renders itself to stringent regulation of the timing, locality and magnitude of its production during an immune response. Subversion of the delicate control and balance frequently leads to immunologic disorders. In this article, we provide an update, since our last review of the subject four years ago, on recent advances in: (1) uncovering of novel activities of IL-12 and related molecules in various immunological settings and models; and (2) dissection of the physiological pathways involved in the modulation of IL-12 production by pathogens and immune regulators. The increased understanding of IL-12 immunobiology and expression will likely benefit the development of therapeutic modalities to correct immune dysfunctions.

Regulation of interleukin-12 gene expression and its anti-tumor activities by prostaglandin E2 derived from mammary carcinomas.

Interleukin-12 (IL-12)-mediated immune responses are critical for the control of malignant development. Tumors can actively resist detrimental immunity of the host via many routes. Prostaglandin E2 (PGE2) is one of the major immune-suppressive factors derived from many types of tumors. Here, we show that systemic administration of recombinant IL-12 could therapeutically control the growth of aggressive TS/A and 4T1 mouse mammary carcinomas. However, PGE2 produced by tumors potently inhibits the production of endogenous IL-12 at the level of protein secretion, mRNA synthesis, and transcription of the constituent p40 and p35 genes. The inhibition can be reversed by NS-398, a selective inhibitor of the enzymatic activity of cyclooxygenase 2 in PGE2 synthesis. Moreover, PGE2-mediated inhibition of IL-12 production requires the functional cooperation of AP-1 and AP-1 strongly suppresses IL-12 p40 transcription. Blocking PGE2 production in vivo results in a marked reduction in lung metastasis of 4T1 tumors, accompanied by enhanced ability of peritoneal macrophages to produce IL-12 and spleen lymphocytes to produce interferon-gamma. This study contributes to the elucidation of the molecular mechanisms underlying the interaction between a progressive malignancy and the immune defense apparatus.

Genome-wide analysis of molecular changes in IL-12-induced control of mammary carcinoma via IFN-gamma-independent mechanisms.

IL-12 is a major activator of tumor-killing NK cells and CTL. IFN-gamma mediates most of the well-known immunological activities of IL-12. In this study, we report IFN-gamma-independent activities induced by therapeutic application of rIL-12 in restricting tumor growth and metastasis in the 4T1 murine mammary carcinoma model. IFN-gamma-deficient mice carrying 4T1 tumor exhibit no gross defect in the number of tumor-infiltrating lymphocytes but have exaggerated angiogenesis in the tumor. Administration of IL-12 is able to constrict blood vessels in the tumor in the absence of IFN-gamma, and retains certain therapeutic efficacy even when applied late during tumor progression. IL-12 exposure in vivo does not irreversibly alter the immunogenicity of the tumor. Finally, global gene expression analysis of primary tumors reveals IL-12-induced molecular patterns and changes, implicating a number of novel genes potentially important for IFN-gamma-independent immune responses against the tumor, for IL-12-mediated antiproliferation, antimetastasis, and antiangiogenesis activities.

Global gene expression profiling in interleukin-12-induced activation of CD8(+) cytotoxic T lymphocytes against mouse mammary Carcinoma.

Interleukin-12 (IL-12) is a critical cytokine representing the link between the cellular and humoral branches of host immune defense apparatus. IL-12-induced cytotoxic lymphocyte (CTL) development is a central mechanism in immune responses against intracellular infectious agents as well as malignant growth. However, the molecular basis of tumor-specific CTL responses mediated by IL-12 remains poorly defined. In this study, we addressed this issue in a comprehensive manner to probe into IL-12-induced anti-tumor responses by global gene expression profiling of mRNA expression in CD8(+) T cells in a transplantable syngeneic mouse mammary carcinoma model treated or not with recombinant IL-12. A strong tumor regression was induced by the IL-12 treatment. An introspection of differential gene expression at an early stage of the IL-12-initiated CTL activation reveals interesting genes and molecular pathways that may account for the marked tumor regression, and is likely to provide a rich source of potential targets for further research and development of effective therapeutic modalities.

Differential regulation of interleukin (IL)-12 p35 and p40 gene expression and interferon (IFN)-gamma-primed IL-12 production by IFN regulatory factor 1.

Interleukin (IL)-12 is a heterodimeric cytokine consisting of the p40 and p35 chains encoded on separate chromosomes. Coordinated expression of the two constituent genes is crucial for appropriate immune responses in timing, location, and magnitude. Interferon (IFN)-gamma priming of IL-12 production by macrophages represents an important physiological process in vivo for escalated cellular response to microbial infections. We provide evidence that IFN regulatory factor (IRF)-1-deficient macrophages have a selective impairment in mRNA synthesis of IL-12 p35 but not the p40 gene, and a strong deficiency in the production of IL-12 p70 but not p40. We demonstrate that the levels of IL-12 p35 protein stimulated by IFN-gamma and lipopolysaccharide (LPS) correspond to those of its mRNA, and that the nuclear factor kappaB signaling pathway is essential for the induction of IL-12 p35 transcription by LPS. IRF-1 plays a major role in the transcriptional activation of the IL-12 p35 gene, but not of the p40 gene, by physically interacting with an inverted IRF element within the IL-12 p35 promoter upon IFN-gamma activation. Moreover, IRF-1-mediated transcriptional activation of the p35 promoter requires the cooperation of two adjacent Sp1 elements. Thus, IRF-1 acts as a critical component of IFN-gamma signaling in the selective activation of IL-12 p35 transcription in synergy with LPS-mediated events.

Preparation of humanized ovarian carcinoma anti-idiotypic minibody.

Murine anti-idiotypic monoclonal antibody (MAb) 6B11 mimicking the tumor-associated antigen OC166-9 is used as a vaccine for the induction of an anti-tumoral immunity in experiments of in vitro and in vivo animal model with ovarian carcinoma. In this article, we have humanized 6B11 anti-idiotypic minibody using overlap polymerase chain reaction (PCR) and DNA recombinant technique, prokaryotic expression vector was produced by genetic fusion of 6B11V(L)-V(H) to human IgG1 hinge and CH3 region. Transformed E. coli BL21(DE3) were propagated and induced by isopropyl-beta D-thiogalactopyranoside (IPTG). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that a protein band with molecular weight of 50kD appeared as the expected size after transformation. Molecular weight of 100 kDa may be examined by electrophoresis in nondenaturing systems. The fusion protein was analyzed with enzyme-linked immunosorbant assay (ELISA), inhibition ELISA tests and Western blot, respectively. The humanized anti-idiotype minibody showed capacity of bivalent binding to ovarian cancer MAb COC166-9 and goat anti-human immunoglobulin IgG1. It is useful reagents for clinical use.

Differential regulation of IL-12 and IL-10 gene expression in macrophages by the basic leucine zipper transcription factor c-Maf fibrosarcoma.

IL-12 is a principal activator of both innate and adaptive immunity against infectious agents and malignancies. Regulation of proinflammatory IL-12 gene expression in phagocytes by the anti-inflammatory cytokine IL-10 represents a major homeostatic process underlying host-pathogen and host-self interactions. Delineation of the signaling pathway of IL-10 is crucial to the understanding of immunological regulatory networks. In this study, we report that IL-10 and c-musculoaponeurotic fibrosarcoma (Maf) induce their mutual expression in inflammatory macrophages. We demonstrate that c-Maf is one of the physiological mediators of IL-10's immunosuppressive activities. When overexpressed, c-Maf selectively inhibits transcriptional activation of IL-12 p40 and p35 genes while potently activating IL-10 and IL-4 expression, potentially contributing to the development of a state of anti-inflammation and dichotomy of immunologic polarization. c-Maf induces changes in nuclear DNA-binding activities at multiple sites including the ets, GA-12, NF-kappaB, C/EBP, and AP-1 elements. Nonetheless, the essential c-Maf-responsive element appears to be located elsewhere. Inhibition of IL-12 p40 gene expression by c-Maf requires the N-terminal transactivation domain, suggesting an indirect mechanism of transcriptional inhibition involving the induction of an unidentified repressor. In c-Maf-deficient murine macrophages, IL-10 production is impaired. However, IL-10-mediated inhibition of IL-12 production remains intact, indicating the existence of alternative mediators in the absence of c-Maf, consistent with the observation that a functional AP-1 is required for this pathway.