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1.
J Mol Model ; 30(7): 231, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38935147

ABSTRACT

CONTEXT: The conversion of carbon dioxide (CO2) to formic acid (FA) through hydrogenation using 1-ethyl-2,3- dimethyl imidazolium nitrite (EDIN) ionic liquid was studied to understand the catalytic roles within EDIN. CO2 hydrogenation in various solvents has been explored, but achieving high efficiency and selectivity remains challenging due to the thermodynamic stability and kinetic inertness of CO2. This study explored two mechanistic pathways through theoretical calculations, revealing that the nitrite (NO2-) group is the most active site. The oxygen site on nitrite favorably activates H2, while the nitrogen site shows a minor activation barrier of 108.90 kJ/mol. The Gibbs energy variation indicates stable FA formation via EDIN, suggesting effective hydrogen (H2) activation and subsequent CO2 conversion. These insights are crucial for developing improved catalytic sites and processes in ionic liquid catalysts for CO2 hydrogenation. METHODS: Quantum chemical calculations were conducted using the ORCA software package at the Restricted Hartree-Fock (RHF) and density functional theory (DFT) levels. The RHF method, known for its predictive abilities in simpler systems, provided a baseline description of electronic structures. In contrast, DFT was employed for its effectiveness in complex interactions involving significant electron correlation. A valence triple-zeta polarization (def2-TZVPP) basis set was employed for both RHF and DFT, ensuring accurate and correlated calculations. The B3LYP functional was utilized for its rapid convergence and cost-efficiency in larger molecules. Dispersion corrected functionals (DFT-D) addressed significant dispersion forces in ionic liquids, incorporating Grimme's D2, D3, and D4 corrections. Geometry optimizations, kinetics, and thermodynamic calculations were performed in the gas phase. The Nudged Elastic Band Transition State (NEB-TS) approach, combining Climbing Image-NEB (CINEB) and Eigenvector-Following (EF) methods, was used to find the minimum energy path (MEP) between reactants and products. Thermochemical analyses based on vibrational frequency calculations evaluated properties such as Enthalpy, Entropy, and Gibbs energy using ideal gas statistical mechanics.

2.
Drugs Aging ; 31(4): 283-9, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24604085

ABSTRACT

BACKGROUND: Poor adherence may have a major impact on clinical outcome, contributing to substantial worsening of disease, increased health care costs and even death. With increasing numbers of medications, low adherence is a growing concern, seriously undermining the benefits of current medical care. Little is known about medication adherence among older adults living at home and requiring complex medication regimens. OBJECTIVE: The aim of this study was to describe adherence to drug prescriptions in a cohort of elderly patients receiving polypharmacy, discharged from an internal medicine ward. METHODS: A sample of elderly patients (65 years of age or older) discharged from an internal medicine ward in Italy throughout 2012 were enrolled. They were followed for 3 months after discharge with a structured telephone interview to collect information on drug regimens and medication adherence 15-30 days (first follow-up) and 3 months (second follow-up) after discharge. Demographic variables including age, sex, marital status and caregiver were collected. RESULTS: Among 100 patients recruited, information on medication adherence was available for, respectively, 89 and 79 patients at the first and second follow-ups. Non-adherence was reported for 49 patients (55.1 %) at the first follow-up and for 55 (69.6 %) 3 months from discharge. Voluntary withdrawal of a drug and change of dosage without medical consultation were the main reasons for non-adherence at both follow-ups. The number of drugs prescribed at discharge was related to medication non-adherence at both follow-up interviews. No association was found between age and non-adherence. Only 25 patients (28.1 %) at the first follow-up and 20 (25.3 %) at the second understood the reasons for their medications. CONCLUSIONS: Low medication adherence is a real, complex problem for older patients receiving polypharmacy. We found that the increasing number of drugs prescribed at hospital discharge is correlated to non-adherence and a high percentage of patients did not understand the purpose of their medications. Simplification of drug regimens and reduction of pill burdens as well as better explanations of the reason for the medications should be targets for intervention.


Subject(s)
Medication Adherence/statistics & numerical data , Polypharmacy , Aged , Aged, 80 and over , Humans , Patient Discharge
3.
J Hum Hypertens ; 22(2): 83-8, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17928879

ABSTRACT

Preclinical vascular changes (increased stiffness and/or wall thickness) have been observed in children with known metabolic risk factors. Aim of the present study was to evaluate different carotid parameters, representative of vascular health, in children with and without metabolic syndrome (MS). We studied 38 children with MS (mean age 9.6+/-2.6 years; range 6-14 years) and 45 healthy age-matched subjects. Children who met three or more of the following criteria qualified as having the MS: fasting glucose >110 mg dl(-1), fasting triglyceride concentration >100 mg dl(-1), fasting high-density lipoprotein cholesterol concentration <50 mg dl(-1) for females or <45 mg dl(-1) for the males, waist circumference >75th percentile for age and gender and systolic or diastolic blood pressure >90th percentile for age, gender and height. Carotid B-mode ultrasound examinations were performed and intima-media thickness and diameters were measured in all subjects. Arterial geometry was further characterized by calculation of carotid cross-sectional area. Carotid intima-media thickness and lumen diameters were increased in children with MS as compared to children without MS. Moreover, carotid cross-sectional area was significantly higher in the group of children with MS 9.83+/-1.86 mm(2) [mean+/-s.d.] compared with the control group: 7.77+/-1.72 mm(2), P<0.001, even after adjustment for age, gender and height. Carotid hypertrophy is already detectable in children with MS. High-resolution B-mode ultrasound could provide a valuable tool for the cardiovascular risk stratification of children.


Subject(s)
Carotid Arteries/pathology , Metabolic Syndrome/pathology , Adolescent , Blood Pressure , Carotid Arteries/diagnostic imaging , Child , Female , Humans , Hypertrophy , Male , Ultrasonography
4.
Ann Rheum Dis ; 59(1): 20-5, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10627422

ABSTRACT

OBJECTIVE: To investigate whether quantitative alterations of both beta(2)microglobulin (beta(2)micro) associated HLA class I heavy chains (sHLA-I) and beta(2) micro free class I heavy chains (sHLA-FHC) in sera of patients with hepatitis C virus (HCV) infection occur and whether they distinguish patients with mixed cryoglobulinaemia (MC). METHODS: 83 HCV infected patients were studied and divided into three groups: (A) without cryoglobulinaemia (n=21), (B) with polyclonal MC (n=20), (C) with monoclonal MC (n=42). Serum sHLA-I and sHLA-FHC were measured by double determinant radioimmunoassay using monoclonal antibodies: TP25.99 as catching antibody, and NAMB-1 and HC-10 as revealing antibodies. Western blot identified HLA-I isoforms. RESULTS: The serum concentrations of sHLA-I and of sHLA-FHC in HCV infected patients versus controls were respectively 1.3(0.5) microg/ml (mean (SD)) versus 0.8 (0.3) (p<0. 001) and 13.9 (7.1) ng/ml versus 9.2 (5) (p<0.001). sHLA-I were 1.01 (0.4) microg/ml in group A, 1.04 (0.4) microg/ml in group B, and 1. 47 (0.4) microg/ml in group C (p=0.001). Statistical analysis showed a significant difference versus controls for groups B (p<0.02) and C (p<0.001). sHLA-FHC were 12.8 (8.3) ng/ml in group A, 17.2 (7.1) ng/ml in group B, and 12.9 (6.2) ng/ml in group C (p<0.02). A significant difference versus controls for each group was found (p<0. 02, p<0.001, and p<0.02, respectively). Different patterns of sHLA-I isoforms were observed. CONCLUSIONS: Increased serum concentrations of sHLA-I and sHLA-FHC characterise HCV infected patients. The highest sHLA-I concentrations seem to distinguish patients with monoclonal MC. In this last condition sHLA could play a part in the HCV escape and in B cell proliferation. The significance of sHLA-FHC is still undefined.


Subject(s)
Cryoglobulinemia/immunology , Hepatitis C/immunology , Histocompatibility Antigens Class I/blood , Adult , Aged , Blotting, Western , Cross-Sectional Studies , Cryoglobulinemia/virology , Female , Hepatitis C/complications , Humans , Male , Middle Aged , Radioimmunoassay/methods , Solubility
5.
Tissue Antigens ; 52(1): 44-50, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9714473

ABSTRACT

The level of soluble beta2-mu-associated HLA Class I heavy chains (sHLA-I) and of soluble beta2-mu-free HLA Class I heavy chains (sHLA-FHC) was found to be significantly higher in sera from 58 patients with systemic lupus erythematosus (SLE) than in those from 82 age and sex-matched controls. The level of serum sHLA-I in patients with SLE was significantly correlated to disease activity. Western blotting analysis showed that the 44-kDa isoform represents the major component in the antigens immunoprecipitated by anti-beta2-mu mAb NAMB-1 and by anti-beta2-mu-free HLA Class I heavy chain mAb HC-10 from sera of patients with SLE. These results suggest that the increased serum levels of sHLA-I and of sHLA-FHC in patients with SLE reflect their increased shedding from cell membrane. In view of the ability of sHLA-I and of sHLA-FHC to induce apoptosis of activated T cells, it is suggested that their increased serum levels in patients with SLE is triggered by dysregulation of the immune system leading to T-cell activation. The increased serum levels of sHLA-I and of sHLA-FHC may be used by the immune system to control the pool of activated T cells by inducing apoptosis. If this possibility is proven to be correct, modulation of the serum level of sHLA-I and of sHLA-FHC may be utilized to develop strategies to treat SLE.


Subject(s)
Histocompatibility Antigens Class I/immunology , Lupus Erythematosus, Systemic/immunology , Adolescent , Adult , Blotting, Western , Female , Humans , Immunoglobulin Heavy Chains/immunology , Lupus Erythematosus, Systemic/blood , Male , Middle Aged , Protein Isoforms
6.
Am J Gastroenterol ; 91(10): 2241-2, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8855762

ABSTRACT

Cholera is a topical infection of the intestinal tract and rarely causes extraintestinal disease. The gallbladder has been proposed to be the reservoir of this organism. We present a patient from Bolivia who developed symptoms of acute cholecystitis and whose bile culture grew Vibrio cholerae 01 El tor.


Subject(s)
Adenocarcinoma/microbiology , Cholecystitis/microbiology , Cholera/complications , Gallbladder Neoplasms/microbiology , Gallbladder/microbiology , Vibrio cholerae/isolation & purification , Bile/microbiology , Bolivia/ethnology , Cholera/epidemiology , Disease Outbreaks , Female , Humans , Middle Aged , New York/epidemiology
7.
South Med J ; 89(5): 522-5, 1996 May.
Article in English | MEDLINE | ID: mdl-8638183

ABSTRACT

In the past, Mycobacterium avium complex (MAC) was considered a colonizing microbe in the immunocompetent host. Today it should be considered a potential pathogen. We present a case of MAC necrotizing pneumonia in a 27-year-old man who tested negatively for the human immunodeficiency virus, had no typical granulomas, and responded rapidly to antimicrobial therapy.


Subject(s)
HIV Seronegativity , Mycobacterium avium-intracellulare Infection/diagnosis , Pneumonia, Bacterial/diagnosis , Adult , Anti-Bacterial Agents/therapeutic use , Anti-Infective Agents/therapeutic use , Antibiotics, Antitubercular/therapeutic use , Antitubercular Agents/therapeutic use , Ciprofloxacin/therapeutic use , Clarithromycin/therapeutic use , Drug Therapy, Combination/administration & dosage , Drug Therapy, Combination/therapeutic use , Ethambutol/therapeutic use , Humans , Male , Necrosis , Pulmonary Atelectasis/microbiology , Rifampin/therapeutic use
8.
Am J Clin Pathol ; 105(2): 216-20, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8607448

ABSTRACT

This is the first case of cyclosporiasis in which the parasite was clearly demonstrated in a duodenal biopsy by light microscopy. Electron microscopy identified the stages of sporozoite, trophozoite, schizont, and merozoite. Although only asexual forms were identified in our case, the sexual cycle must have taken place in the human host, because oocysts were detected in stools of the patients. Therefore, it appears that Cyclospora species require only a single host to complete its entire life cycle. Despite the heavy infection, only enterocytes were invaded. The lamina propria and submucosa were not involved. The morphology of Cyclospora in the intestine is similar to that of Isospora, but differs from that of Cryptosporidium. The morphology of the oocyst of Cyclospora resembles that of Cryptosporidium, but differs from that of Isospora. Thus, a combined study of both stool and intestinal biopsy should readily distinguish Cyclospora from Cryptosporidium and Isospora.


Subject(s)
AIDS-Related Opportunistic Infections/parasitology , Coccidiosis/parasitology , Duodenum/parasitology , Eucoccidiida/growth & development , Intestinal Diseases, Parasitic/parasitology , AIDS-Related Opportunistic Infections/pathology , Adult , Animals , Biopsy , Coccidiosis/pathology , Duodenum/cytology , Duodenum/pathology , Duodenum/ultrastructure , Eucoccidiida/isolation & purification , Eucoccidiida/ultrastructure , Feces/parasitology , Humans , Intestinal Diseases, Parasitic/pathology , Male , Microscopy, Electron , Reproduction, Asexual
10.
Clin Infect Dis ; 15(1): 158-60, 1992 Jul.
Article in English | MEDLINE | ID: mdl-1617055

ABSTRACT

An 88-year-old woman presented with fever, a neck ulcer, and multiple subcutaneous nodules on her upper extremities and thorax. Her condition was initially diagnosed as malignancy associated with metastatic disease to the skin. A subcutaneous nodule was aspirated. A gram stain of the aspirate revealed weakly gram-positive bacilli, and a stain for acid-fast bacilli was positive. Mycobacterium tuberculosis was isolated from a culture of a specimen of the skin lesion.


Subject(s)
Gallbladder Neoplasms/complications , Tuberculosis, Cutaneous/complications , Tuberculosis, Cutaneous/diagnosis , Aged , Aged, 80 and over , Female , Gallbladder Neoplasms/diagnosis , Humans
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