Cardiotonic steroids signaling through the basolateral sodium pump (Na/KATPase) have been shown to alter renal salt handling in intact animals. As the relationship between renal salt handling and blood pressure is a key determinant of hypertension, and patients with insulin resistance are frequently hypertensive, we chose to examine whether there might be competition for resources necessary for receptor mediated endocytosis.
In LLC-PK1 cells, the Na/K-ATPase-α1 and carcinoembryonic antigen cell adhesion molecule (CEACAM1), a plasma membrane protein that promotes receptor-mediated endocytosis, co-localized in the plasma membranes and translocated to the intracellular region in response to ouabain. Either ouabain or insulin alone caused accumulation of CEACAM1 as well as IRβ, and EGFR in early endosomes, but no synergy was demonstrable. Like ouabain, insulin also caused c-Src activation. When caveolin or Na/K-ATPase-α1 expression was knocked down with siRNA, insulin but not ouabain induced CEACAM1, IRβ, and EGFR endocytosis.
To determine whether this might be relevant to salt handling in vivo, we examined salt loading in mice with null renal CEACAM2 expression (Cc2−/−). The Cc2−/− animals demonstrated greater increases in blood pressure with increases in dietary salt than control animals.
These data demonstrate that cardiotonic steroids and insulin compete for cellular endocytosis resources and suggest that under conditions where circulating insulin concentrations are high, cardiotonic steroid mediated natriuresis could be impaired.
chronic renal insufficiency; renal proximal tubule cell; endocytosis
Lemierre's syndrome (LS) is a rare, but a life-threatening complication of an oropharyngeal infection. Combinations of fever, pharyngitis, dysphagia, odynophagia, or oropharyngeal swelling are common presenting symptoms. Infection of the lateral pharyngeal space may result in thrombosis of the internal jugular vein, subsequent metastatic complications (e.g., lung abscesses, septic arthritis), and significant morbidity and mortality. LS is usually caused by the gram-negative anaerobic bacillus Fusobacterium necrophorum, hence also known as necrobacillosis. We present a case of LS caused by Streptococcus intermedius, likely secondary to gingival scraping, in which the presenting complaint was neck pain. The oropharyngeal examination was normal and an initial CT of the neck was done without contrast, which likely resulted in a diagnostic delay. This syndrome can be easily missed in early phases. However, given the potential severity of LS, early recognition and expedient appropriate antimicrobial treatment are critical. S. intermedius is an unusual cause of LS, with only 2 previous cases being reported in the literature. Therefore, an awareness of the myriad presentations of this syndrome, which in turn will lead to appropriate and timely diagnostic studies, will result in improved outcome for LS.
Aglossia congenita (AC), congenital total absence of the tongue, is a very rare midline developmental anomaly, hypothesized to be associated with vascular disruption between the fourth and eighth week of gestation. It was classified by Hall (1971) as part of oromandibular limb hypogenesis syndrome (OLHS) type I B. Most of the cases reported with OLHS are actually hypoglossia with limb abnormalities whereas isolated aglossia is an extremely rare entity. A case of isolated AC is presented in a 28-year-old Indian male. He had long narrow face, tapering chin, low set ears, and microstomia. Intraorally, he had narrow palatal vault, constricted oropharyngeal isthmus, oligodontia, and maxillo-mandibular hypoplasia. Interestingly, the patient showed a median palatal groove, which has not been reported before. He also had an unusual acquired adaptive mechanism to compensate for aglossia. This report presents the manifestations of this rare syndrome, its complications, differential diagnosis, and rehabilitation strategies.
Adaptation; anomaly; developmental; palate; rehabilitation; tongue
The healthy adult human liver expresses low levels of MHC II and undetectable levels of immune co-stimulatory molecules. However, high levels of MHC class II, CD40 and B7 family molecules are expressed in the activated Kupffer cells and hepatocytes of patients having viral hepatitis. The precise role of these molecules in viral clearance and immune-mediated liver injury is not well understood. We hypothesize that parenchymal CD40 expression enhances T-cell recruitment and effector functions, which may facilitate viral clearance and alleviate liver injury. To test this hypothesis, we generated novel, liver-specific, conditional CD40 transgenic mice, and challenged them i.v. with recombinant replication-deficient adenovirus carrying Cre recombinase (AdCre). Wild-type mice infected with AdCre developed a relatively mild course of viral hepatitis and recovered spontaneously. CD40 expression in the liver of transgenic animals, however, resulted in CD80 and CD86 expression. Dysregulation of population dynamics and effector functions of intrahepatic lymphocytes results in severe lymphocytic infiltration, apoptosis, necroinflammation, and serum alanine transferase (ALT) elevation in a dose-dependent fashion. To our surprise, an early expansion followed by a contraction of intrahepatic lymphocytes, especially CD8+ and NK cells, accompanied by increased granzyme B and IFN-γ production, did not lead to a faster viral clearance in CD40 transgenic mice. Conclusion: Our results demonstrated that hepatic CD40 expression does not accelerate adenoviral clearance, but rather exacerbates liver injury. This study unveils a previously unknown deleterious effect of hepatic CD40 in adenovirus-induced liver inflammation.
liver; animal models; T lymphocytes and co-stimulation
Teeth are specialized structural components of the craniofacial skeleton. Developmental defects occur either alone or in combination with other birth defects. Macrodontia of anterior teeth may occur as an isolated condition or as a result of fusion or gemination and can occur in the primary or permanent dentition. Fusion is more commonly seen in the anterior maxillary region. This case presentation reports a case of fusion of a supplemental tooth to one in the normal series in conjunction with a talon cusp. This condition is extremely rare and has been reported at fourth occasion in the literature. The etiology, prevalence, clinical features, and management of the aforementioned anomalies have been reviewed in detail. Early diagnosis of this condition is important because it may cause clinical problems, such as esthetic concerns and tooth crowding.
Fusion; gemination; macrodontia; talon cusp
Hypohidrotic ectodermal dysplasia (HED) is a rare genetic disorder characterized by the faulty development of the ectodermal structure, resulting in most notably anhydrosis/hypohydrosis, hypotrichosis and hypodontia. The condition is usually an X-linked recessive disorder affecting predominantly males. We are here reporting a classical case of hypohidrotic ectodermal dysplasia with a review of the literature.
Ectodermal dysplasia; genetic disorder; hypohidrotic
Thyroid function tests are very important for the diagnosis and monitoring of patients with thyroid dysfunction. The guidelines recommend serum thyroid stimulating hormone (TSH) as the single most reliable test to diagnose all common forms of hypothyroidism and hyperthyroidism. The aim of this study was to analyze the ordering pattern for thyroid function tests by physicians and the analysis of results based on the clinical history. The mean age of the patients was 32.5 ± 6.5 years. Majority of samples (87.7% of total) were received from the departments of Medicine and Gynae. Thyroid profiles (47.5%) were ordered more frequently as compared to TSH only (46%). There was no significant difference in the percentage of normal reports for both types of tests. 77.8% of TFT and 76.6% of TSH samples had results within the reference range. The percentage of abnormal results was 13.7% in the patients who were screened for thyroid disorders. There is a need to redefine the case definition for thyroid dysfunction and order the appropriate test in a rational and cost effective manner.
Thyroid function test; TSH; Hypothyroidism; Hyperthyroidism
Severe alcohol misuse as measured by the Alcohol Use Disorders Identification Test–Consumption (AUDIT-C) is associated with increased risk of future fractures and trauma-related hospitalizations. This study examined the association between AUDIT-C scores and two-year risk of any type of trauma among US Veterans Health Administration (VHA) patients and assessed whether risk varied by age or gender.
Outpatients (215, 924 male and 9168 female) who returned mailed AUDIT-C questionnaires were followed for 24 months in the medical record for any International Statistical Classification of Diseases and Related Health Problems (ICD-9) code related to trauma. The two-year prevalence of trauma was examined as a function of AUDIT-C scores, with low-level drinking (AUDIT-C 1–4) as the reference group. Men and women were examined separately, and age-stratified analyses were performed.
Having an AUDIT-C score of 9–12 (indicating severe alcohol misuse) was associated with increased risk for trauma. Mean (SD) ages for men and women were 68.2 (11.5) and 57.2 (15.8), respectively. Age-stratified analyses showed that, for men ≤50 years, those with AUDIT-C scores ≥9 had an increased risk for trauma compared with those with AUDIT-C scores in the 1–4 range (adjusted prevalence, 25.7% versus 20.8%, respectively; OR = 1.24; 95% confidence interval [CI], 1.03–1.50). For men ≥65 years with average comorbidity and education, those with AUDIT-C scores of 5–8 (adjusted prevalence, 7.9% versus 7.4%; OR = 1.16; 95% CI, 1.02–1.31) and 9–12 (adjusted prevalence 11.1% versus 7.4%; OR = 1.68; 95% CI, 1.30–2.17) were at significantly increased risk for trauma compared with men ≥65 years in the reference group. Higher AUDIT-C scores were not associated with increased risk of trauma among women.
Men with severe alcohol misuse (AUDIT-C 9–12) demonstrate an increased risk of trauma. Men ≥65 showed an increased risk for trauma at all levels of alcohol misuse (AUDIT-C 5–8 and 9–12). These findings may be used as part of an evidence-based brief intervention for alcohol use disorders. More research is needed to understand the relationship between AUDIT-C scores and risk of trauma in women.
Alcohol; Trauma; Fracture; AUDIT-C; Age; Gender; Screening; Women
Panitumumab is a fully human antibody against the epidermal growth factor receptor that is indicated for the treatment of metastatic colorectal cancer (mCRC) after disease progression on standard chemotherapy. The purpose of this analysis was to examine the immunogenicity of panitumumab and to evaluate the effect of anti-panitumumab antibodies on pharmacokinetic and safety profiles in patients with mCRC receiving panitumumab in combination with oxaliplatin- or irinotecan-based chemotherapies.
Three validated assays (two screening immunoassays and a neutralizing antibody bioassay) were used to detect the presence of anti-panitumumab antibodies in serum samples collected from patients enrolled in four panitumumab combination chemotherapy clinical trials. The impact of anti-panitumumab antibodies on pharmacokinetic and safety profiles was analyzed using population pharmacokinetic analysis and descriptive statistics, respectively.
Of 1124 patients treated with panitumumab in combination with oxaliplatin- or irinotecan-based chemotherapy with postbaseline samples available for testing, 20 (1.8%) patients developed binding antibodies and 2 (0.2%) developed neutralizing antibodies. The incidence of anti-panitumumab antibodies was similar in patients with tumors expressing wild-type or mutant KRAS and in patients receiving oxaliplatin- or irinotecan-based chemotherapies. No evidence of an altered pharmacokinetic or safety profile was found in patients who tested positive for anti-panitumumab antibodies.
The immunogenicity of panitumumab in the combination chemotherapy setting was infrequent and similar to the immunogenicity observed in the monotherapy setting. Panitumumab immunogenicity did not appear to alter pharmacokinetic or safety profiles. This low rate of immunogenicity may be attributed to the fully human nature of panitumumab.
ClinicalTrials.gov: NCT00339183 (study 20050181), NCT00411450 (study 20060277), NCT00332163 (study 20050184), and NCT00364013 (study 20050203).
MALDI-TOF mass spectrometry is used here to differentiate different glycoisoforms of normal and variant hemoglobins (Hbs) in nonenzymatic in vitro glycation. Single, double, and/or multiple glycation of the α-globin, β-globin, and/or γ-globin is observed. Different glycation rates are observed for various Hbs, and the normal Hb A has the slowest rate. Although the Hb A is relatively stable upon condensation with glucose at 37°C, the variants Hb C, Hb E, Hb F, Hb Leiden, and Hb San Diego are less stable. In addition, data reveal that the number of glucose attached/Hb molecule (state of glycation) increases with longer incubation time, higher glucose concentration, and higher temperature. The pH dependence of the state of glycation is more complex and varies for different Hbs. Although pH has little effect on the state of glycation for Hb C, Hb E, and Hb Leiden, it increases for Hb A and Hb F upon changing the pH of the solution from phosphate buffer saline (pH 7.4) to carbonate buffer (pH 10). Results obtained in this study could lead to the inference that the linkage of Hbs with glucose occurs in diabetic conditions in vivo (37°C, ∼neutral pH, ∼0.007 M glucose), and the state of glycation is more severe in the individuals who carry abnormal Hbs.
diabetes mellitus; MS
Spironolactone has been noted to attenuate cardiac fibrosis. We have observed that the cardiotonic steroid marinobufagenin plays an important role in the diastolic dysfunction and cardiac fibrosis seen with experimental renal failure. We performed the following studies to determine whether and how spironolactone might ameliorate these changes. First, we studied rats subjected to partial nephrectomy or administration of exogenous marinobufagenin. We found that spironolactone (20 mg/kg per day) attenuated the diastolic dysfunction as assessed by ventricular pressure-volume loops and essentially eliminated cardiac fibrosis as assessed by trichrome staining and Western blot. Next, we examined the effects of spironolactone and its major metabolite, canrenone (both 100 nM), on marinobufagenin stimulation of rat cardiac fibroblasts. Both spironolactone and canrenone prevented the stimulation of collagen production by 1 nM marinobufagenin but not 100 nM marinobufagenin, as assessed by proline incorporation and procollagen 1 expression, as well as signaling through the sodium-potassium-ATPase, as evidenced by protein kinase C isoform δ translocation and extracellular signal regulated kinase 1/2 activation. Both spironolactone and canrenone also altered ouabain binding to cultured porcine cells in a manner consistent with competitive inhibition. Our data suggest that some of the antifibrotic effects of spironolactone may be attributed to antagonism of marinobufagenin signaling through the sodium-potassium-ATPase.
cardiomyopathy; renal failure; cardiotonic steroids; collagen; fibrosis
A two-dimensional immobilized metal affinity electrophoresis method is described here. In this method, ferric ions are immobilized in the second-dimensional polyacrylamide gel to extract the phosphoprotein β-casein from a mixture containing proteins with a broad range of pI and MW. Native 7.5–15% gradient tris-glycine gel with SDS tris-glycine gel running buffer are used so that proteins can be separated according to their molecular mass in the second dimension.
IMAC; IMAEP; 2-D-PAGE; phosphoproteins; β-casein
Romiplostim is an Fc-peptide fusion protein that activates intracellular transcriptional pathways via the thrombopoietin (TPO) receptor leading to increased platelet production. Romiplostim has been engineered to have no amino acid sequence homology to endogenous TPO. Recombinant protein therapeutics can be at a risk of development of an antibody response that can impact efficacy and safety. Hence, a strategy to detect potential antibody formation to the drug and to related endogenous molecules can be useful. The immunogenicity assessment strategy involved both the detection and characterization of binding and neutralizing antibodies. The method for detection was based on a surface plasmon resonance biosensor platform using the Biacore 3000. Samples that tested positive for binding antibodies in the Biacore immunoassay were then tested in a neutralization assay. Serum samples from 225 subjects with immune thrombocytopenic purpura (ITP) dosed with romiplostim and 45 ITP subjects dosed with placebo were tested for romiplostim and TPO antibodies. Prior to romiplostim treatment, 17 subjects (7%) tested romiplostim antibody positive and 12 subjects (5%) tested TPO antibody positive for pre-existing binding antibodies. After romiplostim exposure, 11% of the subjects exhibited binding antibodies against romiplostim and 5% of the subjects with ITP showed binding antibodies against TPO. The antibodies against romiplostim did not cross-react with TPO and vice versa. No cases of anti-TPO neutralizing antibodies were detected in romiplostim-treated subjects. The incidence of anti-romiplostim neutralizing antibodies to romiplostim was 0.4% (one subject); this subject tested negative at the time of follow-up 4 months later. No impact on platelet profiles were apparent in subjects that had antibodies to romiplostim to date. In summary, administration of romiplostim in ITP subjects resulted in the development of a binding antibody response against romiplostim and TPO ligand. One subject developed a neutralizing antibody response to romiplostim that impacted the platelet counts of this subject. No neutralizing antibodies to endogenous TPO were observed.
Immune thrombocytopenic purpura (ITP); Romiplostim; Immunogenicity; TPO; Platelet
Because of the plethora of genetic manipulations available in the mouse, we performed a partial nephrectomy in the mouse and examined whether the phenotypical features of uremic cardiomyopathy described in humans and rats were also present in the murine model. A ⅚ nephrectomy was performed using a combination of electrocautory to decrease renal mass on the left kidney and right surgical nephrectomy. This procedure produced substantial and persistent hypertension as well as increases in circulating concentrations of marinobufagenin. Invasive physiological measurements of cardiac function demonstrated that the ⅚ nephrectomy resulted in impairment of both active and passive left ventricular relaxation at 4 wk whereas tissue Doppler imaging detected changes in diastolic function after 6 wk. Morphologically, hearts demonstrated enlargement and progressive fibrosis, and biochemical measurements demonstrated downregulation of the sarcoplasmic reticulum calcium ATPase as well as increases in collagen-1, fibronectin, and vimentin expression. Our results suggest that partial nephrectomy in the mouse establishes a model of uremic cardiomyopathy which shares phenotypical features with the rat model as well as patients with chronic renal failure.
renal failure; TGF-β; cardiotonic steroids; reactive oxygen species; fibrosis
An immobilized metal affinity electrophoresis (IMAEP) method is described here. In this method, metal ions are immobilized in a native polyacrylamide gel to capture phosphoproteins. The capture of phosphoproteins by IMAEP is demonstrated with immobilized metals like iron, aluminum, manganese, or titanium. In the case studies, phosphoproteins α-casein, β-casein, and phosvitin are successfully extracted from a protein mixture by IMAEP.
IMAC; immobilized metal affinity electrophoresis; phosphoproteins; α-casein; β-casein; phosvitin
We present an improved protocol for coupling synthetic peptides to carrier proteins. In this protocol, dimethyl‐formamide is used as the solvent to solubilize peptides instead of phosphate‐buffered saline (PBS) or 6 M guanidine‐HCl/0.01 M phosphate buffer (pH 7). Additionally, the last desalting or dialyzing step to remove uncoupled peptides as in the traditional method is eliminated. Finally, 3 ml of 0.1 M ammonium bicarbonate is added to the carrier protein conjugated peptide solution to help the lyophilization process. Coupling of Cys‐containing synthetic peptides to keyhole limpet hemocyanin or bovine serum albumin using m‐maleimidobenzoyl‐N‐hydroxysuccinimide ester are used as the test cases. This method produces high‐quality antipeptide antibodies. Also, compared to the traditional method, this procedure is simpler and useful for peptides with solubility problems in PBS or 6 M guanidine‐HCl.
peptide; antibody; KLH; BSA; MBS; DMF; MALDI‐TOF MS
Cartilaginous tumors of laryngeal skeleton are a rarity: Laryngeal chondroma is an unusual cause of upper airway obstruction. The present report illustrates a case of a 13 year old male presenting with mass in the subglottis. Histopathology of the mass revealed laryngeal chondroma.
Cartilaginous tumors; Larynx
Serum iron levels were studied in 50 patients with pre-eclampsia and the results were compared with 50 control cases. Their serum iron levels were found to be higher than the controls. Increase in serum iron was directly proportional to the increased levels of uric acid, urea and creatinine. Mean reticulocyte counts, plasma free haemoglobin and unconjugated bilirubin levels were also higher in these patients. It is suggested that haemolysis may be a major contributory factor for the increased levels of serum iron in pre-eclampsia.
Serum iron; Pre-eclampsia