Radioimmunoassay for human insulin-like growth factor-I receptor: applicability to breast carcinoma specimens and cell lines.

A radioimmunoassay for the human insulin-like growth factor-I (IGF-I) receptor was developed using a rabbit polyclonal antibody to the human IGF-I receptor and a highly purified IGF-I receptor. The purified receptor was radiolabeled with 125I-Bolton-Hunter reagent. Over 18% of the radiolabeled receptor was immunoprecipitated with the polyclonal antireceptor antibody. Purified IGF-I receptor concentrations as low as 5 ng/0.5 mL inhibited the radiolabeled IGF-I receptor binding. Purified insulin receptor weakly inhibited this binding, while the ligand IGF-I did not show inhibition. The radioimmunoassay was applicable to the measurements of IGF-I receptors in the Triton X-100 extracts of various tissues and cells. Breast cancer tissues and cells showed detectable IGF-I receptors, which correlated with IGF-I ligand binding. Receptor content was measurable in placenta and IM-9 cells, but receptor content was not measurable in liver and muscle extracts.     

Metformin enhances certain insulin actions in cultured rat hepatoma cells

Summary The effect of the oral antidiabetic agent metformin on insulin regulation of glycogen metabolism, tyrosine-aminotransferase activity, and [1-¹⁴C]aminoisobutyric acid uptake was studied in H4IIE cultured rat hepatoma cells. Metformin enhanced both basal (from 0.213±0.016 to 0.262±0.024 nmol/mg protein,p<0.01) and insulin stimulated [³H] glucose incorporation into glycogen in a time-dependent and dose-dependent manner. A small effect of metformin was seen at 1 μmol/l, and its greatest effects were obtained at 10 μmol/l. At the same concentrations, metformin did not influence basal tyrosine-aminotransferase activity but it potentiated insulin stimulated tyrosine-aminotransferase activity (+ 29.2±1.4%,p<0.01) and prevented the loss of tyrosine-aminotransferase responsiveness to insulin in H4IIE cells desensitised by a previous exposure to insulin. In contrast, metformin had no effect on basal or insulin-stimulated [1-¹⁴C]aminoisobutyric acid uptake. Over the concentrations of metformin that enhanced insulin action in H4IIE cells, the drug had no significant effect on insulin binding to its receptor. These studies suggest, therefore, that metformin may influence cellular metabolism by potentiating certain insulin actions through mechanisms that may be beyond insulin receptor binding.     

Association among Oral Health,Apical Periodontitis,CD14 Polymorphisms,and Coronary Heart Disease in Middle-aged Adults

Introduction

There is evidence to suggest that an association exists between oral infections and coronary heart disease (CHD). Subjects presenting lesions of endodontic origin (LEOs) or pulpal inflammation had an increased risk of developing CHD. However, findings concerning systemic manifestations of apical periodontitis (AP) remain controversial. An association between CD14 gene polymorphisms and atherosclerosis-associated diseases has been shown, but there are no data regarding an association between CD14 polymorphism and AP. This study evaluated associations between clinical oral health status, CD14 polymorphisms, and CHD.

Methods

A case-controlled clinical trial was designed to compare middle-aged adults with acute myocardial infarction or unstable angina (n = 51) within 12 months of the acute event defined as first manifestation with healthy controls (n = 49). Participants were matched for age, sex, and socioeconomic status. Indicators of oral disease and compliance were evaluated. CD14 polymorphisms were analyzed by restriction fragment length polymorphism–polymerase chain reaction.

Results

CHD subjects had a higher prevalence of oral diseases and lower compliance to oral preventive strategies than healthy controls. Multivariate analysis showed a positive association between missing teeth (odds ratio [OR] = 1.37; 95% confidence interval [CI], 1.02–1.85), the number of LEOs (OR = 4.37; 95% CI, 1.69–11.28), chronic periodontitis (OR = 5.87; 95% CI, 1.17–29.4), and CHD. No statistically significant association emerged between the CD14 C(−260)T and the CD14 C(−159)T polymorphism, endodontic or periodontal disease, and CHD.

Conclusions

Chronic oral diseases may increase the risk of CHD and may be an unconventional risk factor for CHD.     

N-hydroxymethylglycinate with EDTA is an efficient eye drop preservative with very low toxicity: an in vitro comparative study

Purpose: Preservatives are used in multi-dose ophthalmic topical medications in order to prevent contamination by bacteria and fungi. However, prolonged use of preserved eye drops, as it may happen in dry eye or glaucoma, may damage cells of the ocular surface. Therefore, an important goal is to find preservatives with low toxicity which are mild to host cells, still able to prevent drug contamination so to maintain their sterility and efficacy. Hence, aim of this study has been to compare the relative toxicity on a rabbit corneal cell line of a new preservative, made by the association of N-hydroxy-methyl-glycinate (NIG) with disodium-ethylene diamine tetra-acetate (EDTA), with other known and widely used eye-drops preservatives.

Materials and methods: Rabbit corneal cells (SIRC) were tested either in 96-well plates or in suspension culture. Treatments with preservatives (used at known bacteriostatic concentrations) included: benzalkonium chloride (BAK), polyquaternium-1 (PQ-1), sodium perborate (SP: NaBO_{3 *} H₂O), and NIG?±?EDTA at different concentrations (0.001% and 0.002%), and different treatment times (from 30?minutes to 120?hours). At the end of treatment, cell survival was evaluated by a specific spectrophotometric method through the metabolic conversion of MTT [3-(4,5-dimethylthiazol-2-yl) 2, 5-diphenyltetrazolium bromide] into formazan crystals.

Results: Almost no cell toxicity was evident for NIG and SP at either concentration (0.001% or 0.002%), while a low toxicity was observed for PQ-1 (62% at the highest dose at 120?hours). BAK, as expected, showed the highest toxicity (60–80% at 30?minutes, and over 90% from eight hours onward). EDTA 0.1% alone or in combination with NIG 0.002%, showed no toxicity at 24?hours, and even resulted in cell growth promotion (46% and 38%, respectively), after 48?hours of treatment.

Conclusions: These data show that the new preservative NIG/EDTA, at doses known to have effective antimicrobial properties, has a very low toxicity on corneal cells, and so it can be safely used in multi-dose eye drops.     

Percutaneous dilation tracheostomy in a patient with tracheal stent

We reported the case of a patient with obstruction of tracheal stent, deployed previously for anaplastic thyroid carcinoma. The extension of malignant stricture above and below the stent and close to the vocal folds made unfeasible the stent recanalization and/or its replacement with another longer. Thus, tracheostomy was the only option to assure ventilation. After partial air-way recanalization with rigid bronchoscope, tracheostomy cannula was inserted through the stenosis using percutaneous dilatation tracheostomy technique.     

Real-Life Impact of Drug Toxicity on Dolutegravir Tolerability: Clinical Practice Data from a Multicenter Italian Cohort

Dolutegravir (DTG) is currently one of the most used Integrase inhibitors (INI) in antiretroviral therapies (ARV) in both naïve and experienced people living with HIV (PLWHIV). We analyzed a multicenter cohort of PLWHIV, both naïve and experienced, starting an ARV including DTG. We enrolled 3775 PLWHIV: 2763 (73.2%) were males, with a median age of 50 years. During 9890.7 PYFU, we observed 930 discontinuations (9.4 per 100 PYFU). Estimated probabilities of maintaining DTG at three and five years were 75.1% and 67.2%, respectively. Treatment-naïve pts showed a lower probability of maintaining DTG at three and five years compared to treatment-experienced PLWHIV (log-rank p < 0.001). At a multivariate analysis, a longer time of virological suppression (aHR 0.994, p < 0.001) and having experienced a previous virological failure (aHR 0.788, p = 0.016) resulted protective against DTG discontinuation. Most discontinuations (84.0%) happened within the first 12 months of DTG initiation, in particular, 92.2% of discontinuations due to neuropsychiatric toxicity were observed in the first year. Our data confirm the overall good tolerability of DTG in clinical practice, with a low rate of discontinuations. CNS toxicity resulted the main reason for DTG discontinuation, with most related interruptions happening in the first year from DTG introduction.     

Dense red blood cell and oxygen desaturation in sickle‐cell disease

Production of abnormal hemoglobin (HbS) in sickle‐cell disease (SCD) results in its polymerization in deoxygenated conditions and in sickled‐RBC formation. Dense RBCs (DRBCs), defined as density >1.11 and characterized by increased rigidity are absent in normal AA subjects, but present at percentages that vary of a patient to another remaining stable throughout adulthood for each patient. Polymerized HbS has reduced affinity for oxygen, demonstrated by the rightward shift of the oxygen‐dissociation curve, leading to disturbances in oxygen transport. Ninety‐two SCD patients' total RBCs were separated into LightDRBC (LRBC) (d < 1.11 g/mL) and DRBC fractions. Venous blood partial oxygen pressure and RBC‐fraction–deoxygenation and –reoxygenation Hb–oxygen‐equilibrium curves were determined. All patients took a 6‐minute walking test (6MWT); 10 had results before and after >6 months on hydroxyurea. 6MWT time with SpO₂ < 88% (TSpO₂ < 88) assessed the physiological impact of exertion. Elevated mean corpuscular hemoglobin (Hb) concentrations, decreased %HbF, and 2,3‐bisphosphoglycerates in DRBCs modulated Hb–oxygen affinity. Deoxygenation and reoxygenation Hb–oxygen equilibrium curves differed between normal Hb AA and SS RBCs and between LRBCs and DRBCs, with rightward shifts confirming HbS‐polymerization's role in affinity loss. In bivariate analyses, 50% Hb saturation correlated positively with %DRBCs (P < 0.0001, r² = 0.34) and negatively with %HbF (P < 0.0001, r² = 0.25). The higher the %DRBCs, the longer the TSpO₂88 (P = 0.04). Hydroxyurea was associated with significantly shorter TSpO₂ < 88 (P = 0.01). We report that the %DRBCs directly affects SCD patients' SpO₂ during exertion; hydroxyurea improves oxygen affinity and lowers the %DRBCs. Am. J. Hematol. 91:1008–1013, 2016. © 2016 Wiley Periodicals, Inc.