Clinical and hormonal milieu of 9 patients with primary growth hormone insensitivity syndrome and their response to IGF-I generation test

Primary growth hormone insensitivity syndrome (GHIS) is a rare entity which can be due to defects in growth hormone (GH) receptor that is called type 1 Laron syndrome (T1LS) or post receptor defects (type 2 Laron syndrome ). The aim of study was determining the clinical and hormonal milieu of the patients with primary GHIS and their response to IGF-I (insulin like growth factor-I) generation test (IGT). GH, IGF-I, IGF-II, IGF binding protein 1 and 3 (BP-1 and BP-3), GH binding protein (GHBP) and anti-GH antibody were detected by ELISA and RIA methods. IGF-I and BP-3 were measured before and after IGT. Nine patients (8 males, 1 female) (mean age ± SD, 6.4 ± 5 years) with severe short stature and high GH level were studied. Height SDS was - 8.5 ± 2.6. In 7 patients GHBP was zero, IGF-I and BP-3 were low and did not increase after IGT, so they had T1LS. Two brothers did not show the hormonal milieu of GH receptor defect, and were called non Laron syndrome (NLS). Birth weight in patients with T1LS and NLS was 3.65 ± 0.2 Kg and 1.65 ± 0.2 Kg, respectively (P = 0.001). All of the patients had typical clinical feature of GH-deficiency, but nasal bridge depression and microphallus were not seen in NLS. GH treatment of NLS, normalized their growth velocity, but without catch up growth. In conclusion IGT can differentiate Laron syndrome from other types of short stature. GH and IGF-I of fetus have no role in intrauterine growth. © 2006 Tehran University of Medical Sciences. All rights reserved

Biochemical and structural insights into enzymatic depolymerization of polylactic acid and other polyesters by microbial carboxylesterases

Polylactic acid (PLA) is a biodegradable polyester derived from renewable resources, which is a leading candidate for the replacement of traditional petroleum-based polymers. Since the global production of PLA is quickly growing, there is an urgent need for the development of efficient recycling technologies, which will produce lactic acid instead of CO₂ as the final product. After screening 90 purified microbial α/β-hydrolases, we identified hydrolytic activity against emulsified PLA in two uncharacterized proteins, ABO2449 from <i>Alcanivorax borkumensis</i> and RPA1511 from <i>Rhodopseudomonas palustris</i>. Both enzymes were also active against emulsified polycaprolactone and other polyesters as well as against soluble α-naphthyl and <i>p</i>-nitrophenyl monoesters. In addition, both ABO2449 and RPA1511 catalyzed complete or extensive hydrolysis of solid PLA with the production of lactic acid monomers, dimers, and larger oligomers as products. The crystal structure of RPA1511 was determined at 2.2 Å resolution and revealed a classical α/β-hydrolase fold with a wide-open active site containing a molecule of polyethylene glycol bound near the catalytic triad Ser114-His270-Asp242. Site-directed mutagenesis of both proteins demonstrated that the catalytic triad residues are important for the hydrolysis of both monoester and polyester substrates. We also identified several residues in RPA1511 (Gln172, Leu212, Met215, Trp218, and Leu220) and ABO2449 (Phe38 and Leu152), which were not essential for activity against soluble monoesters but were found to be critical for the hydrolysis of PLA. Our results indicate that microbial carboxyl esterases can efficiently hydrolyze various polyesters making them attractive biocatalysts for plastics depolymerization and recycling

Activity screening of environmental metagenomic libraries reveals novel carboxylesterase families

Metagenomics has made accessible an enormous reserve of global biochemical diversity. To tap into this vast resource of novel enzymes, we have screened over one million clones from metagenome DNA libraries derived from sixteen different environments for carboxylesterase activity and identified 714 positive hits. We have validated the esterase activity of 80 selected genes, which belong to 17 different protein families including unknown and cyclase-like proteins. Three metagenomic enzymes exhibited lipase activity, and seven proteins showed polyester depolymerization activity against polylactic acid and polycaprolactone. Detailed biochemical characterization of four new enzymes revealed their substrate preference, whereas their catalytic residues were identified using site-directed mutagenesis. The crystal structure of the metal-ion dependent esterase MGS0169 from the amidohydrolase superfamily revealed a novel active site with a bound unknown ligand. Thus, activity-centered metagenomics has revealed diverse enzymes and novel families of microbial carboxylesterases, whose activity could not have been predicted using bioinformatics tools

Screening and Characterization of Novel Polyesterases from Environmental Metagenomes with High Hydrolytic Activity against Synthetic Polyesters

International audienc

Intermediate versus standard-dose prophylactic anticoagulation and statin therapy versus placebo in critically-ill patients with COVID-19: Rationale and design of the INSPIRATION/INSPIRATION-S studies

Background: Microvascular and macrovascular thrombotic events are among the hallmarks of coronavirus disease 2019 (COVID-19). Furthermore, the exuberant immune response is considered an important driver of pulmonary and extrapulmonary manifestations of COVID-19. The optimal management strategy to prevent thrombosis in critically-ill patients with COVID-19 remains unknown. Methods: The Intermediate versus Standard-dose Prophylactic anticoagulation In cRitically-ill pATIents with COVID-19: An opeN label randomized controlled trial (INSPIRATION) and INSPIRATION-statin (INSPIRATION-S) studies test two independent hypotheses within a randomized controlled trial with 2 � 2 factorial design. Hospitalized critically-ill patients with reverse transcription polymerase chain reaction confirmed COVID-19 will be randomized to intermediate-dose versus standard dose prophylactic anticoagulation. The 600 patients undergoing this randomization will be screened and if meeting the eligibility criteria, will undergo an additional double-blind stratified randomization to atorvastatin 20 mg daily versus matching placebo. The primary endpoint, for both hypotheses will be tested for superiority and includes a composite of adjudicated acute arterial thrombosis, venous thromboembolism (VTE), use of extracorporeal membrane oxygenation, or all-cause death within 30 days from enrollment. Key secondary endpoints include all-cause mortality, adjudicated VTE, and ventilator-free days. Key safety endpoints include major bleeding according to the Bleeding Academic Research Consortium definition and severe thrombocytopenia (platelet count 3 times upper normal limit and clinically-diagnosed myopathy. The primary analyses will be performed in the modified intention-to-treat population. Results will be tested in exploratory analyses across key subgroups and in the intention-to-treat and per-protocol cohorts. Conclusions: INSPIRATION and INSPIRATON-S studies will help address clinically-relevant questions for antithrombotic therapy and thromboinflammatory therapy in critically-ill patients with COVID-19. © 2020 Elsevier Lt

Anti-fibrotic effects of curcumin and some of its analogues in the heart.

Cardiac fibrosis stems from the changes in the expression of fibrotic genes in cardiac fibroblasts (CFs) in response to the tissue damage induced by various cardiovascular diseases (CVDs) leading to their transformation into active myofibroblasts, which produce high amounts of extracellular matrix (ECM) proteins leading, in turn, to excessive deposition of ECM in cardiac tissue. The excessive accumulation of ECM elements causes heart stiffness, tissue scarring, electrical conduction disruption and finally cardiac dysfunction and heart failure. Curcumin (Cur; also known as diferuloylmethane) is a polyphenol compound extracted from rhizomes of Curcuma longa with an influence on an extensive spectrum of biological phenomena including cell proliferation, differentiation, inflammation, pathogenesis, chemoprevention, apoptosis, angiogenesis and cardiac pathological changes. Cumulative evidence has suggested a beneficial role for Cur in improving disrupted cardiac function developed by cardiac fibrosis by establishing a balance between degradation and synthesis of ECM components. There are various molecular mechanisms contributing to the development of cardiac fibrosis. We presented a review of Cur effects on cardiac fibrosis and the discovered underlying mechanisms by them Cur interact to establish its cardio-protective effects

Toxic Effect of Verapamil on Human Perepheral Blood Mononuclear Cells and BALB/c Peritoneal Macrophages in Vitro

Abstract: Background & Aims: Verapamil as a calcium channel blocker has been broadly used in the treatment of many cardiovascular diseases such as hypertension and arrhythmia. Furthermore, the anti-tumor/ anti-inflammatory effects of verapamil have been shown. In the present study, the cytotoxic effect of verapamil on human peripheral blood mononuclear cells (PBMCs) and BALB/c peritoneal macrophges has been evaluated in vitro. Methods: Human PBMCs and BALB/c peritoneal macrophges were cultured in complete RPMI medium. Then the cells at logarhytmic growth phase were incubated with different concentrations of verapamil (2×10-6 - 2×10-3M) for 24, 48 and 72 hours. Subsequently the cell proliferation was assessed with Trypan blue dye exclusion and MTT 3-[4, 5-dimethyl thiazol-2, 5-diphenyltetrazoliumbromide] methods. Results: Verapamil significantly decreased the proliferation of the human PBMCs and BALB/c peritoneal macrophges dose-dependently. This cytotoxic effect was shown at ? 1 mM concentration of the verapamil after 24h incubation time onwards. Moreover, the cytotoxic effect of verapamil at 1mM concentration of the drug increased with time in this order: 24h> 48h>72h. Conclusions: In this study, verapamil showed a dose -dependent cytotoxic effect on the human PBMCs and BALB/c peritoneal macrophges. Since the cytotoxic dose of verapamil on normal cells showed in this study was much higher than that reported for tumor cells, it seems that tumor cells may be more sensitive to verapamil than normal cells. Thus, verapamil could have potential implication in the treatment of cancers. Keywords: Cytotoxicity, verapamil, mononuclear cells, peritoneal macrophage

The effect of Isosorbide Dinitrate on vascular endothelial growth factor production by human leukemic cell lines in vitro

&quot;nBackground: Vascular endothelial growth factor (VEGF) has mitogenic effect for endothelial cells and is an important mediator of tumor expansion, metastasis and angiogenesis in vivo. Isosorbide dinitrate, as a nitric oxide donor, has been widely used in treatment of many cardiovascular diseases such as congestive heart failure and acute coronary syndromes. Furthermore this drug was found to have inhibitory effect on angiogenesis, tumor growth and metastasis in vivo. In the present study we evaluated the isosorbide effect on the VEGF production using some human leukemic cell lines. &quot;nMethods: Human leukemic MOLT-4, JURKAT and U937 cells were cultured in complete RPMI medium. The cells at the exponential growth phase were then incubated with different concentrations of Isosorbide (4&amp;acute;10-7 -4&amp;acute;10-4 M) in the presence or absence of PMA (25ng/ml) for 24 hours. The VEGF concentrations in the culture supernatants were measured by enzyme immunoassay kits (R&amp;amp;D systems) according to the manufacturer&apos;s instructions. &quot;nResults: The level of VEGF produced by the human leukemic cell lines which was treated with different concentrations of isosorbide, did not show any significant difference with untreated control cells. &quot;nConclusions: The results of this study showed that isosorbide had no significant effect on VEGF production. Our findings suggest that anti-angiogenesis effect of isosorbide could be mediated through VEGF-independent mechanism(s). Further studies are warranted to determine definite isosorbide effect on VEGF and other angiogenic factors production in patients as well as animal models

The Effects of Isosorbide Dinitrate on in Vitro Proliferation of WEHI-164 Cells and Peripheral Blood Mononuclear Cells

Background: Isosorbide dinitrate has been broadly used in the treatment of various ischemic heart diseases. Isosorbide is a nitric oxide donor which increases blood flow to tumors through vasodilatation and consequently accelerates the access of chemo-drugs to them. Furthermore, this drug has inhibitory effects on angiogenesis, tumor growth and metastasis in vivo. Moreover, its ant-inflammatory effects have also been reported. In the present study we evaluated the effects of isosorbide on the proliferative activity of fibrosarcoma WEHI-164 cell line and peripheral blood mononuclear cells (PBMCs). Methods: WEHI-164 fibrosarcoma cells and human PBMCs were cultured in complete Roswell Park Memorial Institute (RPMI) 1640 medium with 10% fetal bovine serum and 2×104 cells/mL for WEHI-164 and 2×105 cells/mL for PBMCs. The cells were then incubated at the exponential growth phase with different concentrations of isosorbide (4×10-6-1.6×10-3 M) for 24, 48 and 72 hours. Subsequently, isosorbide effects on proliferation of the cells were evaluated by trypan blue dye exclusion (TB) test and MTT assay. Statistical comparisons between groups were made by analysis of variance. Results: The proliferative activity of WEHI-164 fibrosarcoma cells and human PBMCs treated with different concentrations of isosorbide, did not show any significant difference with untreated control cells. Conclusion: The results of this study showed that isosorbide neither had any significant effects on the proliferative activity of fibrosarcoma WEHI-164 cells nor on human PBMCs. Our findings suggest that anti-tumoral effects of isosorbide reported by other investigators may be mediated through non-cytotoxic mechanisms