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1.
J Endocrinol Invest ; 45(5): 1021-1029, 2022 May.
Article in English | MEDLINE | ID: mdl-35169984

ABSTRACT

OBJECTIVE: Obesity is a recognized risk factor for the progression to severe forms of COVID-19, yet the mechanisms of the association are unclear. METHODS: Subcutaneous abdominal adipose tissue specimens of subjects deceased from COVID-19 (n = 23) were compared to those of controls dying abruptly from causes other than infectious (accidental trauma, sudden cardiac death). Alterations of lung parenchyma consistent with moderate to severe disease were detected in all COVID-19 cases, not in controls. Investigations included: histopathologic features, detection of virus antigens and genome, characterization of infiltrating leukocytes, transcription levels of immune-related genes. RESULTS: By RT-PCR, the SARS-CoV-2 genome was detected in the adipose tissue of 13/23 (56%) cases of the COVID-19 cohort. The virus nucleocapsid antigen was detected in the cytoplasm of 1-5% adipocytes in 12/12 COVID-19 cases that were virus-positive by PCR in the adipose tissue (one case could not be assessed due insufficient tissue). The adipose tissue of COVID-19 cases showed leukocyte infiltrates and upregulation of the interferon-alpha pathway. After adjusting for age and sex, the activation score of IFN-alpha was directly related with transcription levels of the ACE2 gene, a key entry factor of SARS-CoV-2. CONCLUSIONS: In lethal COVID-19 cases, the SARS-CoV-2 nucleocapsid antigen has been detected in a sizeable proportion of adipocytes, showing that the virus may directly infect the parenchymal cells of subcutaneous fat. Infection appears to activate the IFN alpha pathway and to attract infiltrating leukocytes. Due to the huge numbers of adipocytes in adults, the adipose tissue represents a significant reservoir for SARS-CoV-2 and an important source of inflammatory mediators.


Subject(s)
Adipocytes , Adipose Tissue , COVID-19 , Interferon-alpha , SARS-CoV-2 , Adipocytes/immunology , Adipose Tissue/immunology , Adult , COVID-19/diagnosis , COVID-19/immunology , COVID-19/virology , Humans , Interferon-alpha/immunology , SARS-CoV-2/immunology , SARS-CoV-2/isolation & purification
2.
J Endocrinol Invest ; 45(1): 209-214, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34191258

ABSTRACT

PURPOSE: The SARS-CoV-2 genome has been detected in a variety of human samples including blood, urine, semen, and faeces. However, evidence of virus presence in tissues other than lung are limited. METHODS: We investigated whether SARS-CoV-2 could be detected in 50 autoptic specimens of endocrine organs from 29 patients who died of COVID-19. RESULTS: The virus was detected in 25 specimens including ten abdominal subcutaneous adipose tissue samples (62%), six testes (67%), and nine thyroid (36%) samples. The analysis of multiple endocrine organ samples obtained from the same patients showed that, in virus-positive cases, the viral genome was consistently detected in all but two matched specimens. CONCLUSION: Our findings show that the virus spread into endocrine organs is a common event in severe cases. Further studies should assess the rate of the phenomenon in clinically mild cases. The potential long-term effects of COVID-19 on endocrine functions should be taken into consideration.


Subject(s)
COVID-19/virology , Endocrine Glands/virology , SARS-CoV-2/isolation & purification , Abdominal Fat/virology , Adult , Autopsy , COVID-19/epidemiology , Comorbidity , Female , Humans , Lung/virology , Male , Middle Aged , RNA, Viral/analysis , SARS-CoV-2/genetics , Subcutaneous Fat/virology , Testis/virology , Thyroid Gland/virology
3.
J Hosp Infect ; 116: 10-15, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34004223

ABSTRACT

BACKGROUND: In 2010, following the recommendations of the World Health Organization (WHO), our hospital implemented a surgical safety programme centred around a surgical safety checklist. AIM: The aim of this study was to compare indicators of surgical site infection, antimicrobial consumption, antimicrobial resistance, costs and in-hospital mortality before (January 2006 to July 2010) and after (August 2010 to December 2014) implementation of the programme. METHODS: A case-control study was carried out matching patients with surgical site infection (SSI) to surgical patients without infection to examine the impact of the intervention. FINDINGS: Use of the surgical checklist was associated with a significant reduction in SSI. When comparing the two time periods, we also identified a reduction in infections due to micro-organisms in the ESKAPE group (from 90.7% to 73.9%, P<0.001), a reduction of SSI in patients with contaminated, infected and potentially contaminated wounds, and for those in whom perioperative antimicrobial prophylaxis was discontinued in less than 48 hours. Overall, there was a reduction in antimicrobial resistance, though there was increased resistance to carbapenems for, to glycopeptides for Enterococcus faecium, and to clindamycin for Staphylococcus aureus. We also detected increased antimicrobial consumption of second- and third-generation cephalosporins and clindamycin. We observed a reduction in hospital deaths from 6.4% to 3.2% (P=0.001), but we did not observe any reduction in costs. CONCLUSIONS: Implementation of a surgical checklist was an independent predictor of SSI reduction, and was also associated with a decrease in antimicrobial resistance and reduced in-hospital mortality.


Subject(s)
Anti-Bacterial Agents , Surgical Wound Infection , Anti-Bacterial Agents/therapeutic use , Case-Control Studies , Checklist , Drug Resistance, Bacterial , Humans , Surgical Wound Infection/drug therapy , Surgical Wound Infection/epidemiology , Surgical Wound Infection/prevention & control
4.
J Clin Virol ; 110: 1-6, 2019 01.
Article in English | MEDLINE | ID: mdl-30472520

ABSTRACT

BACKGROUND: Typically, hand-foot-and-mouth disease (HFMD) is a mild childhood illness associated with coxsackievirus (CV)-A16, CV-A6, enterovirus (EV)-A71. OBJECTIVES: To identify the viral agents associated with severe cases of atypical HFMD in Italy. STUDY DESIGN: Epidemiologically unrelated cases of severe atypical HFMD admitted to the Emergency Room (ER) of IRCCS San Martino IST (Genoa, Italy) in 2014-2016 were investigated. Serologic screening for viral positivity was performed against exanthem-inducing agents. Ten cases with serology indicative of recent EV infection were selected. Molecular assays were used to detect viral genomes in blood [EVs, Parvovirus B19 (PVB19), herpesviruses (CMV; EBV, HHV-6, -7, -8)]. RESULTS: CV-A6 was detected in 10 cases of severe atypical HFMD. Two cases were also infected with PVB19. Herpesviruses were not detected. Phylogenetic analysis mapped the CV-A6 strains into a single cluster related to two recent isolates from a German and an Asian child. Fever, systemic symptoms, severe vasculitis-like rash, and enanthem were predominant at presentation. Spontaneous recovery occurred in 1-3 weeks. CONCLUSIONS: CV-A6 is emerging as a frequent cause of severe atypical HFMD in Italian adults. This viral agent is disseminating worldwide. Dermatologists must identify the manifold alterations caused by EVs and understand the diagnostic power of current virology methods.


Subject(s)
Antibodies, Viral/blood , Enterovirus A, Human/genetics , Hand, Foot and Mouth Disease/diagnosis , Phylogeny , Adolescent , Adult , Communicable Diseases, Emerging/epidemiology , Communicable Diseases, Emerging/virology , Disease Outbreaks , Enterovirus A, Human/classification , Exanthema/virology , Female , Genome, Viral , Hand, Foot and Mouth Disease/epidemiology , Hand, Foot and Mouth Disease/virology , Hospitalization/statistics & numerical data , Humans , Italy/epidemiology , Male , Middle Aged
5.
J Endocrinol Invest ; 40(10): 1099-1106, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28434158

ABSTRACT

OBJECTIVE: Hypothyroidism is complicated by neuromuscular symptoms (myalgias, slowness of movements, and tiredness) and signs (easy fatigability and cramps), which may have a negative impact on general well-being and quality of life. In a pilot, prospective, controlled study, we investigated the features of muscle dysfunction in hypothyroidism by disease questionnaire, biochemical measures, and physical performance tests. MATERIALS AND METHODS: Fifty-seven consecutive patients with newly diagnosed hypothyroidism were enrolled, 27 subclinical (S-Hypo) and 30 overt (O-Hypo). A series of 30 euthyroid subjects, with similar demographic characteristics, served as controls. Patients were administered a short disease questionnaire and underwent laboratory exams and standardized physical tests, both at baseline and after restoration of biochemical euthyroidism. RESULTS: Compared to euthyroid controls, the O-Hypo group showed significantly higher prevalence of neuromuscular symptoms and significantly higher serum creatine phosphokinase (CPK) levels (p value < 0.0001). S-Hypo had slightly higher CPK levels and prevalence of neuromuscular symptoms than controls. Both S-Hypo and O-Hypo patients performed worse than controls in the six-minute walking test. Differences between patients and controls in handgrip strength test and timed chair standing test failed to reach statistical significance (although a trend was noticeable), possibly due to the small sample size. In O-Hypo, an inverse correlation was found between CPK levels and the handgrip strength test (p value < 0.001). Restoration of euthyroidism was associated with normalization of questionnaire responses, six-minute walking test, as well as serum CPK levels. CONCLUSION: In addition to neuromuscular symptoms, hypothyroidism is associated with abnormalities of physical performance. The six-minute walking test is the most valuable test to assess this aspect. In the pilot study, levothyroxine therapy could reverse muscle functional abnormalities.


Subject(s)
Hand Strength/physiology , Hypothyroidism/physiopathology , Muscle Fatigue/physiology , Muscle Weakness , Quality of Life , Adult , Female , Follow-Up Studies , Humans , Male , Middle Aged , Pilot Projects , Prevalence , Prognosis , Prospective Studies
6.
Allergy ; 72(5): 731-736, 2017 May.
Article in English | MEDLINE | ID: mdl-27659406

ABSTRACT

BACKGROUND: Inappropriate dietary eliminations may impair quality of life, affect children's growth and unnecessarily impact on healthcare costs. Previous retrospective studies reported that around 25% of children continue a food-avoidance diet despite a negative oral food challenge (OFC). A definite pattern has not been found yet for patients not reintroducing the food. This study aimed to examine the role of child's nutritional attitudes and maternal anxiety in reintroducing food after a negative OFC. METHODS: A prospective study was conducted involving 81 mothers of children with IgE-mediated food allergy. They completed a survey on nutritional behaviour and attitudes and the State-Trait Anxiety Inventory on the day of OFC and 6 months later. RESULTS: In total, 11.1% of children never or rarely ate the food after a negative OFC. Consumption of the reintroduced food is positively correlated to child's interest in tasting new foods before and after OFC and to changes in child's nutritional habits after OFC. It is negatively correlated to monotony of the diet after OFC. No correlations were found with other participants' characteristics or maternal anxiety. State anxiety significantly decreased after the OFC. A correlation was found between trait and state anxiety and the degree of change in nutritional habits after OFC. CONCLUSIONS: Evaluating child's approach towards food before the OFC is a promising approach to identify patients at risk of food reintroduction failure. Furthermore, it underlined the importance of reassessing food consumption in all patients after a negative OFC and supporting patients in the reintroduction of food.


Subject(s)
Feeding Behavior , Food Hypersensitivity/epidemiology , Food , Health Knowledge, Attitudes, Practice , Adult , Allergens/immunology , Anxiety , Child , Child, Preschool , Female , Food/adverse effects , Food Hypersensitivity/immunology , Humans , Immunoglobulin E/immunology , Male , Middle Aged , Mothers/psychology , Population Surveillance , Prospective Studies , Surveys and Questionnaires
7.
Allergy ; 72(7): 1054-1060, 2017 Jul.
Article in English | MEDLINE | ID: mdl-27886387

ABSTRACT

BACKGROUND: Food allergy is major public health concern affecting nearly 15 million Americans and 80 million Europeans. Risk of anaphylaxis and implications for social activities affect patients' quality of life and psychological well-being. We previously found that young patients reported higher levels of alexithymia (difficulty in recognizing and expressing emotions) compared with healthy peers and may influence affect, management style and clinical outcomes. This study aimed to explore links between coping strategies, alexithymia and anxiety among food-allergic adolescents and young adults. METHODS: Ninety-two patients with IgE-mediated food allergy (mean age 18.6 years) completed Coping Orientation to Problems Experienced Inventory, Toronto Alexithymia Scale and Trait Anxiety subscale of State-Trait Anxiety Inventory. Multivariate analyses of variance assessed differences and associations between subgroups on the scales. RESULTS: Significant differences found between alexithymia levels in coping style were explained by Avoidance strategies. 'Avoidance' had the highest contribution in explaining alexithymia, followed by trait anxiety, age, anaphylaxis and social support. Respondents with higher alexithymia use avoidance as coping strategy over and above other coping strategies such as problem-solving and positive thinking, are younger, will have experienced anaphylaxis and will have lower social support. CONCLUSIONS: Recognizing the specific role of affect regulation in health behaviours may constitute an important step in supporting patients to explore more adaptive strategies.


Subject(s)
Adaptation, Psychological , Affective Symptoms , Anxiety , Food Hypersensitivity/psychology , Adolescent , Adult , Age Factors , Female , Food Hypersensitivity/diagnosis , Food Hypersensitivity/immunology , Humans , Immunoglobulin E/immunology , Male , Quality of Life , Young Adult
8.
Am J Infect Control ; 44(9): 1058-60, 2016 09 01.
Article in English | MEDLINE | ID: mdl-27156199

ABSTRACT

We performed a quasi-experimental, cohort study in the medical-surgical inpatient wards comparing central line-associated bloodstream infection (CLABSI) rates and microbiologic characteristics in 3 phases. The CLABSI rates decreased 60% from phase 1 to 2 and 61.5% from phase 2 to 3. Gram-positive organisms were most frequently isolated in phases 1 and 3, and gram-negative bacilli were most frequently isolated in phase 2. The CLABSI surveillance and prevention program focusing on patient safety had a significant impact on CLABSI rates.


Subject(s)
Bacteremia/prevention & control , Catheter-Related Infections/prevention & control , Catheterization, Central Venous/adverse effects , Epidemiological Monitoring , Infection Control/methods , Organizational Objectives , Bacteremia/epidemiology , Catheter-Related Infections/epidemiology , Cohort Studies , Gram-Negative Bacteria/isolation & purification , Gram-Positive Bacteria/isolation & purification , Humans , Intensive Care Units , Patient Safety
9.
Psychol Health Med ; 20(6): 732-41, 2015.
Article in English | MEDLINE | ID: mdl-25531062

ABSTRACT

Maternal stress in fetal and early life has been associated with the development of respiratory allergies, but no studies exist about food allergy. Stressful events and the quality of caregiving provided, as they affect the emotional and physiologic regulation of the infant, could alter the hypothalamic-pituitary-adrenal and immune system, facilitating an increased allergic response. This study aimed to investigate the influence of perinatal stress, as perceived by mothers, on developing food allergy in childhood. A survey on pregnancy and the first three months after giving birth was submitted to 59 Italian mothers of at least one child suffering from severe food allergy and one completely healthy child, for a total of 118 children examined. The presence of stressful events and the quality of perinatal period for each child were assessed retrospectively. The food allergic children's data were compared to siblings' data through inferential statistics. The results showed a significantly higher number of stressful events occurred during patients' perinatal period, compared to siblings, in particular bereavements in pregnancy and parenting difficulties in postpartum. Mothers reported harder pregnancies and more stressful, harder, and, in general, worse postpartum when referring to their food-allergic children, in comparison with their siblings (p < .05). Psychological aspects are demonstrated to be involved in the development of allergic diseases. This study constitutes the first step to examine the role of early stress and perinatal psychosocial factors in the pathogenesis of food allergy; further studies are necessary to understand individual psychological impact and its relations with genetic and biological factors.


Subject(s)
Food Hypersensitivity/epidemiology , Mothers/psychology , Postpartum Period/psychology , Pregnancy Complications/psychology , Prenatal Exposure Delayed Effects/epidemiology , Stress, Psychological/psychology , Adolescent , Adult , Case-Control Studies , Child , Female , Humans , Italy/epidemiology , Male , Middle Aged , Pregnancy , Retrospective Studies , Self Report , Surveys and Questionnaires
10.
Eur Rev Med Pharmacol Sci ; 17(16): 2240-9, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23893192

ABSTRACT

OBJECTIVES: The safety and effectiveness of autologous mesenchymal cells for treating bone defects in humans is still uncertain. The present study presents a new technique consisting of allogeneic bone grafting enriched with bone marrow concentrate to treat acetabular bone defects resulting from aseptic loosening of the acetabular cup after total hip replacement. PATIENTS AND METHODS: Five adult patients were included in the study. Prior to surgery, patients were tested for antibodies to common pathogens. Treatment consisted of bone allogeneic scaffold seeded with bone marrow mesenchymal cells harvested from the iliac crest and concentrated using an FDA-cleared device. Clinical and radiographic follow-up was performed at 1, 3, 6, and 12 months after surgery. To assess viability, morphology, and the immunophenotype, bone marrow nucleated cells were cultured in vitro, then tested for sterility and evaluated for the possible replication of adventitious viruses. RESULTS: In 4 of 5 patients, both clinical and radiographic healing of the bone defect together with bone graft integration was observed at the mean time of 3.5 months. Mean follow-up was 2 years. One patient failed to respond. No post-operative complications were observed. Bone marrow nucleated cells were enriched 3.8-fold by a single concentration step. Enriched cells were free of microbial contamination. The immunophenotype of adherent cells was compatible with that of mesenchymal stem cells. No viral reactivation was observed. CONCLUSIONS: Allogeneic bone scaffold enriched with concentrated autologous bone marrow cells obtained from the iliac crest, may represent a good alternative to treat acetabular bone defects observed in revision hip arthroplasty.


Subject(s)
Acetabulum/pathology , Arthroplasty, Replacement, Hip/methods , Bone Transplantation/methods , Mesenchymal Stem Cell Transplantation/methods , Aged , Arthroplasty, Replacement, Hip/adverse effects , Bone Marrow Cells/metabolism , Bone Transplantation/adverse effects , Female , Follow-Up Studies , Humans , Male , Mesenchymal Stem Cell Transplantation/adverse effects , Reoperation , Time Factors , Tissue Scaffolds , Transplantation, Homologous , Treatment Outcome
11.
Diabetologia ; 56(8): 1856-66, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23616239

ABSTRACT

AIM/HYPOTHESIS: Monocytes/macrophages play important roles in adipose and vascular tissues and can be polarised as inflammatory M1 or anti-inflammatory M2. We sought to analyse monocyte polarisation status in type 2 diabetes, which is characterised by chronic inflammation. METHODS: We enrolled 60 individuals without diabetes and 53 patients with type 2 diabetes. We quantified standard monocyte subsets defined by cluster of differentiation (CD)14 and CD16. In addition, based on the phenotype of polarised macrophages in vitro, we characterised and quantified more definite M1 (CD68(+)CCR2(+)) and M2 (CX3CR1(+)CD206(+)/CD163(+)) monocytes. We also analysed bone marrow (BM) samples and the effects of granulocyte-colony stimulating factor (G-CSF) stimulation in diabetic and control individuals. RESULTS: We found no alterations in standard monocyte subsets (classical, intermediate and non-classical) when comparing groups. For validation of M1 and M2 phenotypes, we observed that M2 were enriched in non-classical monocytes and had lower TNF-α content, higher LDL scavenging and lower transendothelial migratory capacity than M1. Diabetic patients displayed an imbalanced M1/M2 ratio compared with the control group, attributable to a reduction in M2. The M1/M2 ratio was directly correlated with waist circumference and HbA1c and, among diabetic patients, M2 reduction and M1/M2 increase were associated with microangiopathy. A decrease in M2 was also found in the BM from diabetic patients, with a relative M2 excess compared with the bloodstream. BM stimulation with G-CSF mobilised M2 macrophages in diabetic but not in healthy individuals. CONCLUSIONS/INTERPRETATION: We show that type 2 diabetes markedly reduces anti-inflammatory M2 monocytes through a dysregulation in bone-marrow function. This defect may have a negative impact on microangiopathy.


Subject(s)
Bone Marrow/immunology , Diabetes Mellitus, Type 2/immunology , Diabetic Angiopathies/immunology , Monocytes/cytology , Adult , Aged , Aged, 80 and over , Bone Marrow/metabolism , Cells, Cultured , Female , Humans , Male , Middle Aged , Monocytes/immunology
12.
Arch Pediatr ; 16(3): 227-34, 2009 Mar.
Article in French | MEDLINE | ID: mdl-19179056

ABSTRACT

OBJECTIVE: Very preterm children can experience cognitive and behavioral difficulties. The aim of this study was to assess the impact of very preterm birth on visuospatial processes at preschool age. DESIGN AND METHODS: Data come from the Epipage study. Participants underwent a follow-up evaluation at age 5 years. During the psychological evaluation, children took subtests of the K-ABC and the WPPSI-R. Six subtests are based on visuospatial information. RESULTS: The results concern 183 children assessed in the Lorraine region of France, who were born with birthweight appropriate for gestational age and had no neurological sequelae. Thirty-six children were born at term, 112 were born very prematurely (28-32 GW), and 35 were born extremely prematurely (<28 GW). Birth term was significantly correlated with performance on the six subtests. In all cases, the children born at term obtained higher scores compared to the children born very prematurely and extremely prematurely. On two subtests of the K-ABC, the children born extremely prematurely obtained lower scores than those of the children born very prematurely. The mother's level of education was correlated with performance on three subtests. CONCLUSION: The results suggest that a very preterm birth can exert a negative impact on visuospatial and visuomotor processes. These deficits may involve difficulties in some activities at school and in daily life.


Subject(s)
Infant, Premature/physiology , Pattern Recognition, Visual/physiology , Space Perception/physiology , Child, Preschool , Educational Status , Female , Follow-Up Studies , Humans , Infant, Newborn , Infant, Premature/growth & development , Intelligence Tests , Male
13.
Arch Pediatr ; 13(9): 1195-201, 2006 Sep.
Article in French | MEDLINE | ID: mdl-16824742

ABSTRACT

OBJECTIVE: A preterm birth can exert an influence on cognitive development. The aim of this study was to determine whether preterm birth may impact on attention executive processes, at school age, in children without neurological sequelae. DESIGN AND METHODS: Prematurely born children admitted in the level III NICU of the Maternité régionale of Nancy between 1992 and 1994, underwent at 8 to 10 years 8 subtests of the mental processing scales of the K-ABC, which assess process categories involved in learning. The children were also submitted to 3 tests that evaluate attention mechanisms efficiency (category fluency task, backward digits span, Tower of London). The controls were children born at term recruted in schools of the same area. RESULTS: The 124 children were born with birth weight appropriate for gestational age, and were in the school grades expected for their ages, in 3rd, 4rth, and 5fth grades. Fifty-three children were born at term, 29 were prematurely born (33-36 w), and 42 were very prematurely born (28-32 w). Birth term was significantly correlated (P < 0.001) with scores at sequential processing scale, at simultaneous processing scale and at the mental processing composite scale. At this scale, the children born at term obtained a median score of 112, the children prematurely born of 101, and the children very prematurely born of 98.5. For 40 third grade children (18 born at term, 10 prematurely born, and 12 very prematurely born), birth term was significantly correlated with performances at the 3 tests of attention. In all cases, preterm was inversely correlated with performances. CONCLUSION: The results are consistent with a lower efficiency in attention executive processes which may be related to the higher frequency of learning disabilities associated with prematurity.


Subject(s)
Attention/physiology , Cognition Disorders/physiopathology , Premature Birth/physiopathology , Birth Weight/physiology , Case-Control Studies , Child , Female , Follow-Up Studies , Humans , Male , Neuropsychological Tests
14.
J Chem Phys ; 123(23): 234308, 2005 Dec 15.
Article in English | MEDLINE | ID: mdl-16392921

ABSTRACT

We have studied the cis-->trans and trans-->cis photoisomerization of azobenzene after n-->pi* excitation using the full multiple spawning (FMS) method for nonadiabatic wave-packet dynamics with potential-energy surfaces and couplings determined "on the fly" from a reparametrized multiconfigurational semiempirical method. We compare the FMS results with a previous direct dynamics treatment using the same potential-energy surfaces and couplings, but with the nonadiabatic dynamics modeled using a semiclassical surface hopping (SH) method. We concentrate on the dynamical effects that determine the photoisomerization quantum yields, namely, the rate of radiationless electronic relaxation and the character of motion along the reaction coordinate. The quantal and semiclassical results are in good general agreement, confirming our previous analysis of the photodynamics. The SH method slightly overestimates the rate of excited state decay, leading in this case to lower quantum yields.

15.
Faraday Discuss ; 127: 149-63, 2004.
Article in English | MEDLINE | ID: mdl-15471344

ABSTRACT

We use ab initio results to reparameterize a multi-reference semiempirical method to reproduce the ground and excited state potential energy surfaces (PESs) for the chromophore of Green Fluorescent Protein (GFP). The validity of the new parameter set is tested, and the new method is combined with a quantum mechanical/molecular mechanical (QM/MM) treatment so that it can be applied in the solution phase. Solvent effects on the energetics of the relevant conical intersections are explored. We then combine this representation of the ground and excited state PESs with the full multiple spawning (FMS) nonadiabatic wavepacket dynamics method to simulate the photodynamics of the neutral GFP chromophore in both gas and solution phases. In these calculations, the PESs and their nonadiabatic couplings are evaluated simultaneously with the nuclear dynamics, ie. "on-the-fly". The effect of solvation is seen to be quite dramatic, resulting in an order of magnitude decrease in the excited state lifetime. We observe a correlated torsion about a double bond and its adjacent single bond in both gas and solution phases. This is discussed in the context of previous proposals about minimal volume isomerization mechanisms in protein environments.


Subject(s)
Luminescent Proteins/chemistry , Green Fluorescent Proteins , Models, Molecular , Protein Conformation , Quantum Theory , Solvents , Thermodynamics
17.
J Endocrinol ; 182(3): 479-84, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15350189

ABSTRACT

The expression of Fas in thyroid tumours and Graves' disease was analysed by mRNA transcript expression. As compared with unaffected thyroid tissue, Fas expression was enhanced in Graves' disease, adenomas, and papillary and follicular carcinomas. This pattern was also reflected in immunohistochemical studies. The PCR single-strand conformational polymorphism (SSCP) method and DNA sequencing were used to analyse Fas exons 1-9. The study was carried out on five different histotypes of thyroid tumours (n=93) and tissue from Graves' disease patients. As compared with a group of healthy blood donors (n=64), a significant association (P=0.006) emerged between papillary thyroid carcinoma and a silent single nucleotide polymorphism (SNP, 988C-->T) in exon 7 of the Fas gene. Other forms of thyroid pathology were not associated with the above polymorphism. Patients with neoplasia showed the same SNP in tumour tissue, in the unaffected contralateral thyroid lobe, and in peripheral blood cells. Thus, the 988C-->T polymorphism appeared to be of germ-line origin.


Subject(s)
Adenoma/metabolism , Carcinoma, Papillary/metabolism , Germ-Line Mutation , Polymorphism, Single Nucleotide , Thyroid Neoplasms/metabolism , fas Receptor/genetics , Carcinoma, Papillary, Follicular , Case-Control Studies , Graves Disease/metabolism , Humans , Immunohistochemistry/methods , Polymorphism, Single-Stranded Conformational , Sequence Analysis, DNA , fas Receptor/analysis
18.
J Am Chem Soc ; 125(42): 12710-1, 2003 Oct 22.
Article in English | MEDLINE | ID: mdl-14558810

ABSTRACT

The photoisomerization mechanism of the neutral form of the photoactive yellow protein (PYP) chromophore is investigated using ab initio quantum chemistry and first-principles nonadiabatic molecular dynamics (ab initio multiple spawning or AIMS). We identify the nature of the two lowest-lying excited states, characterize the short-time behavior of molecules excited directly to S2, and explain the origin of the experimentally observed wavelength-dependent photoisomerization quantum yield.


Subject(s)
Bacterial Proteins/chemistry , Coumaric Acids/chemistry , Photoreceptors, Microbial/chemistry , Isomerism , Photochemistry , Propionates , Quantum Theory , Spectrometry, Fluorescence
19.
Scand J Immunol ; 56(5): 448-55, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12410794

ABSTRACT

The protective activity of a DNA plasmid encoding the immunodominant capsid protein VP1 of coxsackievirus B4 (CBV-4) was studied in BALB/c mice. The plasmid pCI-B4-1-c - which gave the highest expression level of VP1 in cultured monkey and human cells - was chosen for immunization. Two injections of pCI-B4-1-c (1 month apart) into the regenerating mouse muscle tissue induced a specific antibody response to CBV-4, as shown by immunoenzyme and neutralization assays. Upon challenge with live CBV-4, the mortality rate of mice vaccinated with the recombinant plasmid was significantly reduced (21% versus >58%) as compared with that of mice that had been either nontreated or injected with a control plasmid devoid of the insert. The VP1-based vaccine, however, did not provide complete protection as - after virus challenge - moderate viraemia occurred together with modest plasma elevations of pathogenesis-related enzymes (amylase and creatine kinase). Yet, immunofluorescence of the small intestine and heart did confirm the protective effect of the VP1-encoding vaccine. In order to obtain a more complete protection against CBV-4, it may be beneficial to immunize mice with combinations of separate DNA plasmids encoding not only VP1 but also the VP2 and VP3 capsid proteins.


Subject(s)
Capsid Proteins/immunology , Enterovirus B, Human/immunology , Vaccines, DNA/pharmacology , Viral Vaccines/pharmacology , Animals , Antibodies, Viral/blood , Antigens, Viral/genetics , COS Cells , Capsid Proteins/genetics , Cell Line , Enterovirus B, Human/genetics , Enterovirus B, Human/pathogenicity , Enterovirus B, Human/physiology , Enterovirus Infections/immunology , Enterovirus Infections/prevention & control , Humans , Kinetics , Male , Mice , Mice, Inbred BALB C , Plasmids/genetics , Vaccines, DNA/genetics , Viral Vaccines/genetics , Virus Replication
20.
New Microbiol ; 25(3): 323-9, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12173774

ABSTRACT

The Phoenix Automated Microbiology System (Becton Dickinson, Sparks, MD) was evaluated for its ability to identify nonfermenting gram-negative pathogens and measure their drug susceptibility. Isolates producing rare extended-spectrum beta-lactamases (PER-1, IMP-2, VIM-1, and VIM-2) were included in the study. Species identification was compared to that given by the ATB System (bio-Mérieux, Marcy l'Etoile, France), whereas susceptibility results were compared to those produced by a reference broth microdilution test (panels manufactured by Pasco Laboratories, Becton Dickinson). The Phoenix system consistently identified all isolates of Pseudomonas aeruginosa (n = 55) and Stenotrophomonas maltophilia (n = 28), while in other cases species agreement was obtained for 47/53 isolates (Acinetobacter baumannii, 29/31; Pseudomonas putida, 10/11; Burkholderia cepacia, 6/7; and Pseudomonas fluorescens, 2/4). Overall, the Phoenix and ATB systems gave equal results in 130/136 cases (95.6%). For two isolates, consistent identification was obtained at the genus level, thus bringing the cumulative agreement to 97.1%. MIC values (interpreted according to NCCLS guidelines) gave essential and categorical agreement in 94.2% and 93.1% of cases, respectively. Minor and major errors were 5.1% and 5.2%, respectively. No very major errors were produced. The mean time to results (TTR) for the Phoenix system was 14.8 +/- 1.6 h (mean +/- SD), with the shortest TTR being observedfor A. baumannii (13.0 +/- 1.8 h) and the longest one for P. aeruginosa (15.6 +/- 1.2 h). In conclusion, the Phoenix system performed rapidly and correctly in the identification of clinical isolates of important opportunistic pathogens and in measuring their susceptibility to antipseudomonal drugs.


Subject(s)
Bacterial Typing Techniques/methods , Gram-Negative Bacteria/classification , Gram-Negative Bacteria/drug effects , Microbial Sensitivity Tests/methods , Automation , Gram-Negative Bacterial Infections/microbiology , Humans
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