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1.
J Phys Chem C Nanomater Interfaces ; 127(48): 23270-23284, 2023 Dec 07.
Article in English | MEDLINE | ID: mdl-38090142

ABSTRACT

Clusterization-triggered emission (CTE) of nonconventional chromophores has recently attracted increased interest for its synergetic photophysical properties and promising applications, such as optical anticounterfeiting, white-light emission devices, or molecular sensing. Many studies have been conducted on pure organic clusteroluminogens (CLgens), but very few have explored organic-inorganic hybrid (OIH) materials. This work deals with optical properties of a new OIH compound (TET)2[Pb4Cl16] (TET = N,N'-bis(2-aminoethyl)-1,3-propanediamine (C7N4H24)), which presents an unprecedented two-dimensional perovskitoid structure formed by strongly distorted [Pb4Cl16] layers of corner and edge-sharing [PbCl6] octahedra, separated by TET tetra-ammonium cations. Under UV-visible excitations, (TET)2[Pb4Cl16] exhibits white-light emission, tunable excitation-wavelength-dependent emission, and green afterglow room temperature phosphorescence (RTP) lasting for more than 0.63 s, all of which are direct signatures of CTE. The optical interpretations are supported by density functional theory (DFT) calculations of the band structure. Two mechanisms are involved in the emission process: resonant energy transfer (RET) between the organic and the inorganic components, and clusteroluminescence (CL) governed by a rigid conformation of the organic cations and extended electron delocalization over supramolecular organic clusters confined within the interlayer spacing. The different features of CLgens in (TET)2[Pb4Cl16] are discussed, and the role of the organic nonconjugated molecule in the emission process is emphasized.

2.
J Org Chem ; 87(9): 6444-6453, 2022 05 06.
Article in English | MEDLINE | ID: mdl-35467869

ABSTRACT

The 1,3-dipolar cycloaddition reaction of isoquinolinium ylides to nitrostilbenes provides an approach to 1,2-diarylpyrrolo[2,1-a]isoquinolinium-3-carboxylates and then to a complete hexacyclic lamellarin core.


Subject(s)
Cycloaddition Reaction
3.
Eur J Clin Microbiol Infect Dis ; 36(9): 1643-1649, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28401320

ABSTRACT

Streptococcus pyogenes (GAS) is one of the major human pathogenic bacteria that cause a wide range of diseases. Currently, increased incidence of streptococcal invasive infections is observed worldwide. In this study, we focused on the prevalence of genes encoding superantigens and type M proteins in the population of GAS strains from invasive versus non-invasive infections. We tested 253 GAS strains: 48 strains from patients with invasive infections (18 from wound/deep skin localization, 30 from women in labour) and 205 strains from non-invasive forms (147 from common infections of the upper respiratory, 49 from the vagina of females with genital tract infections and 9 from non-invasive wound and superficial skin infections). Significant differences were found in the occurrence of genes: speG, speI, speJ and smeZ, which were more common in GAS isolated from invasive than from non-invasive strains; speJ and smeZ occurred more frequently in strains from invasive perinatal infections versus strains from women without symptoms of invasive infection; speH and speI in strains from invasive skin/wound infection versus strains isolated from non-invasive wound and superficial skin infections. Emm types 1 and 12 predominated in the group of strains isolated from superficial infections and type 28 in those from puerperal fever. Occurrence of genes encoding virulence factors is common in genomic DNA of most of S. pyogenes, regardless whether these streptococcal infections are invasive or non-invasive. On the other hand, it appears that strains with speG, speI, speJ and smeZ genes may have a particular potential for virulence.


Subject(s)
Streptococcal Infections/epidemiology , Streptococcal Infections/microbiology , Streptococcus pyogenes/genetics , Streptococcus pyogenes/pathogenicity , Virulence Factors/genetics , Antigens, Bacterial/genetics , Bacterial Outer Membrane Proteins/genetics , Carrier Proteins/genetics , Female , Genotype , History, 21st Century , Humans , Male , Serogroup , Streptococcal Infections/diagnosis , Streptococcal Infections/history , Streptococcus pyogenes/classification , Virulence/genetics
4.
Eur J Clin Microbiol Infect Dis ; 35(5): 747-54, 2016 May.
Article in English | MEDLINE | ID: mdl-26873375

ABSTRACT

Invasive group A streptococcal (GAS) infections constitute an important epidemiological problem. Many cases occur in women during the postnatal period. The objective of this study was to evaluate the presence of the genes responsible for production of iron-chelating protein (perR) and superantigens (speA, speB, speC, speF, speG, speH, speI, speJ, speK, speL, speM, smeZ, and ssa) in S. pyogenes strains isolated from invasive infections in women after delivery. Furthermore, this study sought to verify whether S. pyogenes strains show special phenotypic and genotypic (sla, spy1325) characteristics that may play a decisive role in adherence to the genital tract epithelium. Moreover, the emm-types and antibiotic susceptibility were determined. We tested 30 invasive S. pyogenes strains isolated from postpartum invasive infection and 37 GAS control strains isolated from the genital tracts of asymptomatic multiparous women. The majority of the tested strains were shown to express two types of emm genes (1 and 28), though emm -12, -28, -75 and -89 were uniquely expressed in the group of strains isolated from invasive infections. A significantly higher prevalence of perR in the strains from puerperal fever was shown. Significant differences were also found between the two groups with respect to the incidence of the genes related to adherence; GAS strains originating from women with sepsis/puerperal fever showed presence of these genes less frequently than those of the control group. Although differences in frequencies of the gene coding for various superantigens were noted between the compared groups of GAS strains, they were not significant.


Subject(s)
Pregnancy Complications, Infectious/microbiology , Streptococcal Infections/microbiology , Streptococcus pyogenes/pathogenicity , Bacterial Adhesion/genetics , Drug Resistance, Bacterial , Female , Genes, Bacterial , Genotype , Humans , Microbial Sensitivity Tests , Pregnancy , Serogroup , Streptococcus pyogenes/classification , Streptococcus pyogenes/drug effects , Streptococcus pyogenes/genetics , Virulence Factors/genetics
5.
Eur J Clin Microbiol Infect Dis ; 34(6): 1135-43, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25655758

ABSTRACT

The aim of the study was to investigate whether there are unique pathotypes of Escherichia coli capable of transmission from the gastrointestinal tract to the vascular bed. The study included E. coli strains isolated from clinical materials collected from 115 patients suffering from haematologic malignancies diagnosed with bacteraemia. The genotyping techniques established that 89 E. coli isolates from the blood had the same genotype as the E. coli from the patient's bowel. The presence of 21 genes encoding virulence factors typical of various E. coli pathotypes and their relationship with the phylogenetic group was established. One-dimensional analysis showed that the focG gene occurred more frequently in the control bowel group, while the ampicillin-resistant afa/dr E. coli were associated with bacteraemia. Blood isolates with the highest occurrence of virulence factors belonged to pathogenic group B2 and non-pathogenic group A. The co-occurrence of multiple genes encoding papC, sfa, usp and cnf1 virulence factors probably predisposes E. coli to translocation from the gastrointestinal tract to the vascular bed in the group of patients with haematologic malignancies. Based on clustering analysis, dominance of the most virulent strains assigned to the cluster with seven virulence factors encoded by the following genes, papC, sfaD/E, cnf1, usp, agn43, hlyA and iutA, was found. The obtained results enforce the previously proposed concept of bowel-blood translocation and further expand our hypothesis by defining the unique virulence characteristics of E. coli isolates, which predispose them to bowel colonisation or translocation and bacteraemia in this group of patients.


Subject(s)
Bacteremia/microbiology , Bacterial Translocation , Blood/microbiology , Escherichia coli Infections/microbiology , Escherichia coli/isolation & purification , Virulence Factors/analysis , Adolescent , Adult , Aged , Aged, 80 and over , Escherichia coli/genetics , Female , Gastrointestinal Tract , Genotype , Humans , Male , Middle Aged , Retrospective Studies , Virulence Factors/genetics , Young Adult
6.
Eur J Clin Microbiol Infect Dis ; 32(12): 1579-82, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23801304

ABSTRACT

An analysis of the phylogenetic distribution and virulence genes of Escherichia coli isolates which predispose this bacteria to translocate from the urinary tract to the bloodstream is presented. One-dimensional analysis indicated that the occurrence of P fimbriae and α-hemolysin coding genes is more frequent among the E. coli which cause bacteremia. However, a two-dimensional analysis revealed that a combination of genes coding two adherence factors, namely, P + Dr, P + S, S + Dr, S + fim, and hemolysin + one adherence factor, were associated with bacteremia and, therefore, with the risk of translocation to the vascular system. The frequent and previously unrecognized co-existence of pro-inflammatory P fimbriae with the invasion promoting Dr adhesin in the same E. coli isolate may represent high-risk and potentially lethal pathogens.


Subject(s)
Bacterial Adhesion/genetics , Bacterial Translocation/genetics , Escherichia coli Infections/microbiology , Escherichia coli Proteins/genetics , Escherichia coli/physiology , Bacteremia/microbiology , Escherichia coli/genetics , Escherichia coli/pathogenicity , Fimbriae, Bacterial/genetics , Genes, Bacterial , Hemolysin Proteins/genetics , Humans , Risk
7.
Eur J Clin Microbiol Infect Dis ; 32(11): 1393-400, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23649557

ABSTRACT

In patients with leukemia, the portal(s) and reasons for the persistence of an Escherichia coli recurrent bacteremia remain unclear. Adult Hematology Clinic (AHC) databases at the State Clinical Hospital in Gdansk were reviewed to evaluate the frequency of E. coli bacteremia between 2002 and 2005. Blood and bowel E. coli strains were obtained and the genetic relatedness of the strains was analyzed. The rate of E. coli bacteremia per 1,000 admissions at the AHC was higher (85.0) than in the other clinics of the hospital (2.9), p < 0.001. A higher mortality was observed in patients with a history of E. coli versus non-E. coli bacteremia [30/95 (31 %) vs. 53/430 (12 %), p < 0.001]; 72.8 % of patients with leukemia had an unknown source of bacteremia. In 2005, 6 out of 25 (24 %) patients with leukemia had ≥2 episodes of E. coli-positive blood cultures. These gastrointestinal E. coli isolates were replaced within 3-8 weeks with a new E. coli H genotype. A recurrent episode of bacteremia was usually caused by an infection with a transient E. coli H genotype identical to that found in the subject's bowel. Consistent with the definition of bowel/blood translocation, the bowel appeared to be a portal for E. coli in these subjects and, hence, a clear source for their recurring bacteremia.


Subject(s)
Bacteremia/epidemiology , Bacteremia/microbiology , Bacterial Translocation , Escherichia coli Infections/epidemiology , Escherichia coli Infections/microbiology , Escherichia coli/classification , Leukemia/complications , Adult , Blood/microbiology , Colon/microbiology , Escherichia coli/genetics , Escherichia coli/isolation & purification , Humans , Molecular Typing , Recurrence , Risk Assessment
8.
Transplant Proc ; 43(8): 2985-90, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21996206

ABSTRACT

INTRODUCTION: Urinary tract infections (UTIs) are most common infections in renal transplant recipients and are considered a potential risk factor for poorer graft outcomes. AIM: To evaluate incidence, clinical manifestations, microbiology, risk factors for UTIs, and the influence of UTIs on long-term renal graft function. PATIENTS AND METHODS: We analyzed urine cultures with reference to clinical data of patients who received a renal transplantation from January to December 2009 with a 12-month follow-up. RESULTS: The 1170 urine cultures were correlated with clinical data from 89 renal transplant recipients, including 58.4% males and on overall mean age of 48±14 years. The 151 episodes in 49 patients consisted of asymptomatic bacteriuria (65%, n=98); lower UTIs (13%, n=19); and upper UTIs (22%, n=34), as well as five cases of bacteremia. Nearly 48% of UTIs were diagnosed during the first month posttransplantation. The most frequently isolated uropathogens were Enterococcus faecium (33%, n=24) and Escherichia coli (31%, n=23). Beginning from the second month, most frequently found bacterium in urine cultures was E coli (65% n=51). Risk factors for posttransplant UTIs were female gender and a history of an acute rejection episode and/or a cytomegalovirus (CMV) infection. All patients with vesicoureteral reflux of strictures at the ureterovesical junction suffered recurrent UTIs (n=7). The evolution of renal graft function did not differ significantly between patients with versus without UTIs. CONCLUSIONS: UTIs a frequent problem after kidney transplantation most commonly exist as asymptomatic bacteriuria. E coli and E faecium are ther predominant pathogens. Exposure to intensified immunosuppression due to acute rejection episodes or CMV infections represents a risk factor for UTIs. Vesicoureteral reflux or strictures at the ureterovesical junction are risk factors for recurrent UTIs. UTIs did not impair 1-year graft function.


Subject(s)
Kidney Transplantation/adverse effects , Urinary Tract Infections/etiology , Adult , Bacteriuria/etiology , Cohort Studies , Enterococcus faecium , Escherichia coli Infections/etiology , Female , Gram-Positive Bacterial Infections/etiology , Humans , Incidence , Kidney Transplantation/physiology , Male , Middle Aged , Multivariate Analysis , Retrospective Studies , Risk Factors , Time Factors , Urinary Tract Infections/epidemiology
11.
J Anim Physiol Anim Nutr (Berl) ; 92(4): 448-55, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18662354

ABSTRACT

This study was performed to analyse the effects of low-protein diet (7%) on bone mass and mineral metabolism in rat pups whose mothers were submitted to protein-restricted diet during late pregnancy and early post-natal periods. For this purpose, 12 pregnant Wistar rats were divided into two groups of six animals each: a control group with free access to standard diet (20% protein) and protein-restricted group (PR) fed with low-protein diet (7% protein) from the 14th day of pregnancy until day 14 after delivery. Body weight, femur bone mass, plasma thyroid hormones (FT(4) and FT(3)), biochemical bone marker levels [alkaline phosphatase (ALP), tartrate-resistant acid phosphatase (ACP)] and bone DNA content were recorded. In undernourished pups, a decrease in body weight (-47%, p < 0.001) in skeletal growth (-11%, p < 0.001) and in bone DNA content (-48%, p < 0.001) were observed. Plasma protein and albumin levels and thyroid status were also decreased in undernourished rat pups compared with those of control group. The circulating amino acid levels were decreased in pups. While in their mothers, some of them were increased and the others were decreased. A positive correlation was observed between bone mass and plasma thyroid hormone levels and ALP activity and plasma protein levels, and a negative correlation with ACP activity. Plasma ALP levels were decreased by 19%, whereas plasma tartrate-resistant ACP levels were increased by 33% indicating a hyperactivity of bone remodelling. These results showed that protein-restricted diet given to mothers during late pregnancy and early post-natal periods induced changes in body weight, skeletal growth and bone metabolism in their offspring.


Subject(s)
Animals, Newborn/growth & development , Animals, Newborn/metabolism , Animals, Suckling/metabolism , Bone and Bones/metabolism , Diet, Protein-Restricted , Minerals/metabolism , Animals , Female , Maternal Nutritional Physiological Phenomena/physiology , Pregnancy , Prenatal Exposure Delayed Effects , Prenatal Nutritional Physiological Phenomena/physiology , Random Allocation , Rats , Rats, Wistar , Thyroid Hormones/blood
13.
Ann Fr Anesth Reanim ; 24(10): 1287-90, 2005 Oct.
Article in French | MEDLINE | ID: mdl-16125360

ABSTRACT

We report two cases of postobstructif pulmonary oedema occurring after extubation at the recovery of general anaesthesia and presenting some similarities. The young age of the patient and the occurrence of upper airway obstruction after extubation, as well as the radiologic nondependent distribution of alveolar pattern are typical. The underlying pathophysiology seems to be the mechanical disruption of the alveolar-capillary membrane.


Subject(s)
Airway Obstruction/complications , Anesthesia, General , Intubation, Intratracheal/adverse effects , Postoperative Complications/etiology , Postoperative Complications/therapy , Pulmonary Edema/etiology , Pulmonary Edema/therapy , Adult , Anesthesia Recovery Period , Appendicitis/surgery , Cardiomegaly/etiology , Echocardiography , Electrocardiography , Humans , Male , Pulmonary Alveoli/diagnostic imaging , Pulmonary Alveoli/pathology , Pulmonary Edema/diagnostic imaging , Radiography , Rectal Fistula/surgery
14.
Ann Endocrinol (Paris) ; 66(2 Pt 1): 96-104, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15959409

ABSTRACT

The aim of our work is to study dimethoate effects on thyroid function given in drinking water (40 mg/kg body weight, equivalent to 0.2 g/L) to mothers from day zero until the 10th day after delivery. Pups and their mothers were sacrificed on day ten after parturition. Compared to a control group, dimethoate-treated pups showed a 48% decrease in body weight which could be attributed to a defect in thyroid hormones. Indeed, after treatment by dimethoate, plasma rates of free T4 and T3 decreased by 56% and 40% in the young and by 27% and 15% in dams respectively. We can attribute the reduction in plasma thyroxine and triiodothyronine rates to a decrease in thyroid iodine levels (-75%) in the young and (-24%) in their mothers. The decrease in production of thyroid hormones after dimethoate treatment affect thyroid stimulating hormone (TSH) levels. In fact, plasma TSH levels were multiplied in dimethoate-treated group by factors of 2.31 in dams and 1.96 in their offspring. These biochemical modifications confirmed the histological thyroid aspects of pups and dams. In fact, in dimethoate-treated rats, some thyroid follicles of pups presented vesicular cavities without colloid; others contained colloid. However in dams, thyroid follicles presented cubical epithelial cells which surrounded empty vesicular cavities.


Subject(s)
Animals, Suckling , Dimethoate/toxicity , Insecticides/toxicity , Thyroid Diseases/chemically induced , Thyroid Gland/physiopathology , Animals , Body Weight , Dimethoate/administration & dosage , Female , Femur/growth & development , Femur/pathology , Insecticides/administration & dosage , Iodine/analysis , Maternal-Fetal Exchange , Organ Size , Pregnancy , Rats , Rats, Wistar , Thyroid Diseases/metabolism , Thyroid Diseases/physiopathology , Thyroid Gland/chemistry , Thyroid Gland/growth & development , Thyrotropin/blood , Thyroxine/blood , Triiodothyronine/blood
16.
Harefuah ; 140(8): 706-8, 806, 2001 Aug.
Article in Hebrew | MEDLINE | ID: mdl-11547471

ABSTRACT

Verrucous carcinoma is a rare type of squamous cell carcinoma that is most commonly seen in the oral cavity, and seldom in the larynx. It should be distinguished from benign papilloma, verrucous hyperplasia and well-differentiated non verrucous squamous cell carcinoma. Verrucous carcinoma is a rare tumor of the sinonasal tract. Only 28 such cases have been described in the medical literature reviewed until this time. We describe the first case in Israel of a patient with such a tumor in the nasal cavity. We reviewed the existing literature dealing with Verrucous Carcinoma of paranasal sinuses.


Subject(s)
Carcinoma, Verrucous/pathology , Carcinoma, Verrucous/surgery , Maxillary Neoplasms/pathology , Maxillary Neoplasms/surgery , Nose Neoplasms/pathology , Nose Neoplasms/surgery , Aged , Humans , Male
17.
J Laryngol Otol ; 115(9): 699-703, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11564294

ABSTRACT

We present the results of the insertion of self-made polyethylene T-tubes for a period of 15-24 months for the treatment of chronic middle-ear effusion. We compare the outcome of our patients to the reported outcome of patients treated with other commonly used ventilation tubes for either shorter or longer periods of time. In a retrospective review of 603 T-tubes inserted in 306 children up to the age of 12 years, charts were reviewed for age, sex, surgical procedure performed, duration of ventilation and complications. In all cases the indication for surgery was chronic middle-ear effusion. The tubes were electively removed by the authors after 15-24 months of ventilation. Spontaneous extrusion was considered a complication. The mean period of ventilation was 20 months. Post-operative otorrhoea was experienced in 6.6 per cent of ears; 4.8 per cent of tubes extruded spontaneously, whereas 3.15 per cent had to be removed earlier than originally planned; 4.9 per cent of ears were re-ventilated at a later date, and 1.49 per cent of ears developed a persistent perforation. We demonstrate that the outcome of patients treated with our self-manufactured tubes for a period of 15-24 months is, in many respects, better or at least comparable to the reported outcome of patients treated with other commonly used ventilation tubes for either shorter or longer periods of time, and that the many complications associated with the conventional T-tube can be reduced. We suggest that our favourable outcome may be due to the duration of ventilation, which was controlled to be shorter than the conventional long-term T-tubes and longer than that of grommets.


Subject(s)
Middle Ear Ventilation/instrumentation , Otitis Media with Effusion/surgery , Child , Child, Preschool , Chronic Disease , Female , Humans , Infant , Male , Retrospective Studies , Treatment Outcome
18.
J Laryngol Otol ; 115(9): 760-2, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11564314

ABSTRACT

Vascular transformation of lymph node sinuses is an uncommon condition and only isolated cases have been reported. It is characterized by conversion of nodal sinuses into capillary-like channels, often accompanied by fibrosis. Venous or lymphatic obstruction is thought to be the underlying mechanism, and in most cases factors that may contribute to lymphovascular obstruction can be identified such as tumour in the vicinity, vascular thrombosis, heart failure, previous surgery or radiotherapy. Most cases involve abdominal lymph nodes, and head and neck involvement is rare. We present two cases of vascular transformation of lymph node sinuses presenting only as cervical lymphadenopathy, without an obvious cause of lymphovascular obstruction.


Subject(s)
Lymph Nodes/pathology , Lymphatic Diseases/pathology , Adult , Endothelium, Vascular/pathology , Female , Humans , Immunoenzyme Techniques , Lymph Node Excision , Lymphatic Diseases/surgery , Male , Middle Aged , Neck
20.
Can J Anaesth ; 48(5): 493-6, 2001 May.
Article in English | MEDLINE | ID: mdl-11394521

ABSTRACT

PURPOSE: To report the case of a patient who underwent right thoracoscopic pleurectomy with lung exclusion and developed contralateral (left) pneumothorax with resulting life-threatening alteration of the respiratory and cardiovascular functions. CLINICAL FEATURES: A 28-yr-old male was admitted to the intensive care unit for a well tolerated, second episode of spontaneous right pneumothorax and scheduled for right thoracoscopic pleurectomy. Anesthesia was induced and maintained with sufentanil and propofol. A double lumen endotracheal tube (ETT) was inserted, its correct positioning checked clinically and by fiberoptic bronchoscopy and the patient was placed in the left decubitus position. Approximately one hour into the procedure, during the second period of right pulmonary exclusion, SpO2 values decreased within two minutes to 78%. End tidal capnography (EtCO2) values decreased to 6-8 mmHg within seconds and peak airway pressure increased to values between 50 and 60 cm H2O. Severe cyanosis, sinus bradycardia and arterial hypotension developed. The surgical procedure was stopped, propofol administration discontinued, bipulmonary ventilation reinstituted and the patient placed in the supine position which restored hemodynamic and respiratory function. Inspection and auscultation were consistent with tension left pneumothorax which was evacuated. CONCLUSION: Pneumothorax of the ventilated lung during one lung ventilation for thoracoscopic procedures must be diagnosed quickly. Reinstitution of bipulmonary ventilation should probably be the first therapeutic attitude.


Subject(s)
Endoscopy , Intraoperative Complications/therapy , Pleura/surgery , Pneumonectomy , Pneumothorax/therapy , Respiration, Artificial , Adult , Anesthesia, Inhalation , Blood Gas Analysis , Humans , Intraoperative Complications/diagnosis , Male , Pneumothorax/diagnosis , Thorax
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