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1.
BMC Public Health ; 21(1): 1920, 2021 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-34686158

RESUMEN

BACKGROUND: Adverse childhood experiences (ACEs) increases vulnerability to externalising disorders such as substance misuse. The study aims to determine the prevalence of ACEs and its association with substance misuse. METHODS: Data from the Consortium on Vulnerability to Externalising Disorders and Addictions (cVEDA) in India was used (n = 9010). ACEs were evaluated using the World Health Organisation (WHO) Adverse Childhood Experiences International Questionnaire whilst substance misuse was assessed using the WHO Alcohol, Smoking and Substance Involvement Screening Test. A random-effects, two-stage individual patient data meta-analysis explained the associations between ACEs and substance misuse with adjustments for confounders such as sex and family structure. RESULTS: 1 in 2 participants reported child maltreatment ACEs and family level ACEs. Except for sexual abuse, males report more of every individual childhood adversity and are more likely to report misusing substances compared with females (87.3% vs. 12.7%). In adolescents, family level ACEs (adj OR 4.2, 95% CI 1.5-11.7) and collective level ACEs (adj OR 6.6, 95% CI 1.4-31.1) show associations with substance misuse whilst in young adults, child level ACEs such as maltreatment show similar strong associations (adj OR 2.0, 95% CI 1.1-3.5). CONCLUSION: ACEs such as abuse and domestic violence are strongly associated with substance misuse, most commonly tobacco, in adolescent and young adult males in India. The results suggest enhancing current ACE resilience programmes and 'trauma-informed' approaches to tackling longer-term impact of ACEs in India. FUNDING: Newton Bhabha Grant jointly funded by the Medical Research Council, UK (MR/N000390/1) and the Indian Council of Medical Research (ICMR/MRC-UK/3/M/2015-NCD-I).


Asunto(s)
Experiencias Adversas de la Infancia , Maltrato a los Niños , Violencia Doméstica , Trastornos Relacionados con Sustancias , Adolescente , Niño , Estudios de Cohortes , Femenino , Humanos , Masculino , Trastornos Relacionados con Sustancias/epidemiología
2.
Epidemiol Infect ; 147: e294, 2019 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-31637988

RESUMEN

Mycetoma is a chronic granulomatous, suppurative and progressive inflammatory disease that usually involves the subcutaneous tissue and bones after traumatic inoculation of the causative organism. In India, actinomycotic mycetoma is prevalent in south India, south-east Rajasthan and Chandigarh, while eumycetoma, which constitutes one third of the total cases, is mainly reported from north India and central Rajasthan. The objective was to determine the epidemiological profile and spectrum of eumycetoma from a tertiary care hospital in Delhi, North India. Thirty cases of eumycetoma were diagnosed by conventional methods of direct microscopy, culture and species-specific sequencing as per standard protocol. The spectrum of fungal pathogens included Exophiala jeanselmei, Madurella mycetomatis, Fusarium solani, Sarocladium kiliense, Acremonium blochii, Aspergillus nidulans, Fusarium incarnatum, Scedosporium apiospermum complex, Curvularia lunata and Medicopsis romeroi. Eumycetoma can be treated with antifungal therapy and needs to be combined with surgery. It has good prognosis if it is timely diagnosed and the correct species identified by culture for targeted therapy of these patients. Black moulds required prolonged therapy. Its low reporting and lack of familiarity may predispose patients to misdiagnosis and consequently delayed treatment. Hence health education and awareness campaign on the national and international level in the mycetoma belt is crucial.


Asunto(s)
Micetoma/epidemiología , Enfermedades Desatendidas/epidemiología , Adolescente , Adulto , Femenino , Humanos , India/epidemiología , Masculino , Persona de Mediana Edad , Micetoma/diagnóstico , Micetoma/terapia , Enfermedades Desatendidas/diagnóstico , Enfermedades Desatendidas/terapia , Pronóstico , Estudios Retrospectivos , Adulto Joven
3.
Artículo en Inglés | MEDLINE | ID: mdl-29437624

RESUMEN

Estimating epidemiological cutoff endpoints (ECVs/ECOFFS) may be hindered by the overlap of MICs for mutant and nonmutant strains (strains harboring or not harboring mutations, respectively). Posaconazole MIC distributions for the Aspergillus fumigatus species complex were collected from 26 laboratories (in Australia, Canada, Europe, India, South and North America, and Taiwan) and published studies. Distributions that fulfilled CLSI criteria were pooled and ECVs were estimated. The sensitivity of three ECV analytical techniques (the ECOFFinder, normalized resistance interpretation [NRI], derivatization methods) to the inclusion of MICs for mutants was examined for three susceptibility testing methods (the CLSI, EUCAST, and Etest methods). The totals of posaconazole MICs for nonmutant isolates (isolates with no known cyp51A mutations) and mutant A. fumigatus isolates were as follows: by the CLSI method, 2,223 and 274, respectively; by the EUCAST method, 556 and 52, respectively; and by Etest, 1,365 and 29, respectively. MICs for 381 isolates with unknown mutational status were also evaluated with the Sensititre YeastOne system (SYO). We observed an overlap in posaconazole MICs among nonmutants and cyp51A mutants. At the commonly chosen percentage of the modeled wild-type population (97.5%), almost all ECVs remained the same when the MICs for nonmutant and mutant distributions were merged: ECOFFinder ECVs, 0.5 µg/ml for the CLSI method and 0.25 µg/ml for the EUCAST method and Etest; NRI ECVs, 0.5 µg/ml for all three methods. However, the ECOFFinder ECV for 95% of the nonmutant population by the CLSI method was 0.25 µg/ml. The tentative ECOFFinder ECV with SYO was 0.06 µg/ml (data from 3/8 laboratories). Derivatization ECVs with or without mutant inclusion were either 0.25 µg/ml (CLSI, EUCAST, Etest) or 0.06 µg/ml (SYO). It appears that ECV analytical techniques may not be vulnerable to overlap between presumptive wild-type isolates and cyp51A mutants when up to 11.6% of the estimated wild-type population includes mutants.


Asunto(s)
Antifúngicos/farmacología , Aspergillus fumigatus/efectos de los fármacos , Aspergillus fumigatus/genética , Mutación/genética , Triazoles/farmacología , Farmacorresistencia Fúngica/genética , Pruebas de Sensibilidad Microbiana , Voriconazol/farmacología
4.
Med Mycol ; 56(2): 186-196, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-28525619

RESUMEN

Formal, large-scale, multicenter studies of invasive mould infection (IMI) in Asia are rare. This 1-year, retrospective study was designed to assess the incidence and clinical determinants of IMI in centers in five countries (Thailand, Taiwan, Singapore, China, India). Patients treated in a single year (2012) were identified through discharge diagnoses, microbiology, and histopathology logs, and entered based on published definitions of IMI. A total of 155 cases were included (median age 54 years; 47.7% male). Of these, 47.7% had proven disease; the remainder had probable IMI. The most frequent host factors were prolonged steroid use (39.4%) and recent neutropenia (38.7%). Common underlying conditions included diabetes mellitus (DM; 30.9%), acute myeloid leukemia (19.4%), and rheumatologic conditions (11.6%). DM was more common in patients with no recent history of neutropenia or prolonged steroid use (P = .006). The lung was the most frequently involved site (78.7%), demonstrating a range of features on computed tomography (CT). Aspergillus was the most common mould cultured (71.6%), primarily A. fumigatus and A. flavus, although proportions varied in different centers. The most often used antifungal for empiric therapy was conventional amphotericin. Ninety-day mortality was 32.9%. This is the first multicenter Asian study of IMI not limited to specific patient groups or diagnostic methods. It suggests that DM and rheumatologic conditions be considered as risk factors for IMI and demonstrates that IMI should not be ruled out in patients whose chest features on CT do not fit the conventional criteria.


Asunto(s)
Hongos/fisiología , Infecciones Fúngicas Invasoras/epidemiología , Infecciones Fúngicas Invasoras/microbiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Asia/epidemiología , Aspergillus/fisiología , Niño , Preescolar , Femenino , Humanos , Incidencia , Infecciones Fúngicas Invasoras/diagnóstico , Infecciones Fúngicas Invasoras/tratamiento farmacológico , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento , Adulto Joven
5.
Indian J Clin Biochem ; 33(1): 81-85, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29371774

RESUMEN

The prevalence of non-communicable diseases like diabetes mellitus (DM) and hypertension (HTN) is growing worldwide. Both lead to nephropathy if not controlled effectively. Microalbuminuria (MAU) is recognized as an early predictor for nephropathy. Additionally, the timely detection of advanced glycation end products (AGEs) is also considered to be an important prognostic factor for diabetic nephropathies. Hence, screening for the early detection of MAU and AGEs would be an useful and relatively inexpensive laboratory test for early clinical diagnosis for the incidence of nephropathy in these diseases. This study was conducted in DM, HTN and pregnancy induced hypertensive (PIH) subjects. MAU and Nε-Carboxymethyllysine (CML) levels were estimated by in-house RIA kits in the patient groups and controls, while the total AGEs level in serum was determined by ELISA. The levels of MAU, CML and AGE-BSA were observed to be significantly higher in DM, HTN and PIH subjects compared to controls (p < 0.001). Increased serum CML and AGEs levels in DM, HTN and PIH subjects indicated ongoing glycemic damage and their susceptibility to develop renal complications.

6.
Artículo en Inglés | MEDLINE | ID: mdl-28739796

RESUMEN

Clinical and Laboratory Standards Institute (CLSI) conditions for testing the susceptibilities of pathogenic Sporothrix species to antifungal agents are based on a collaborative study that evaluated five clinically relevant isolates of Sporothrixschenckii sensu lato and some antifungal agents. With the advent of molecular identification, there are two basic needs: to confirm the suitability of these testing conditions for all agents and Sporothrix species and to establish species-specific epidemiologic cutoff values (ECVs) or breakpoints (BPs) for the species. We collected available CLSI MICs/minimal effective concentrations (MECs) of amphotericin B, five triazoles, terbinafine, flucytosine, and caspofungin for 301 Sporothrix schenckii sensu stricto, 486 S. brasiliensis, 75 S. globosa, and 13 S. mexicana molecularly identified isolates. Data were obtained in 17 independent laboratories (Australia, Europe, India, South Africa, and South and North America) using conidial inoculum suspensions and 48 to 72 h of incubation at 35°C. Sufficient and suitable data (modal MICs within 2-fold concentrations) allowed the proposal of the following ECVs for S. schenckii and S. brasiliensis, respectively: amphotericin B, 4 and 4 µg/ml; itraconazole, 2 and 2 µg/ml; posaconazole, 2 and 2 µg/ml; and voriconazole, 64 and 32 µg/ml. Ketoconazole and terbinafine ECVs for S. brasiliensis were 2 and 0.12 µg/ml, respectively. Insufficient or unsuitable data precluded the calculation of ketoconazole and terbinafine (or any other antifungal agent) ECVs for S. schenckii, as well as ECVs for S. globosa and S. mexicana These ECVs could aid the clinician in identifying potentially resistant isolates (non-wild type) less likely to respond to therapy.


Asunto(s)
Anfotericina B/farmacología , Antifúngicos/farmacología , Equinocandinas/farmacología , Flucitosina/farmacología , Lipopéptidos/farmacología , Naftalenos/farmacología , Sporothrix/efectos de los fármacos , Esporotricosis/tratamiento farmacológico , Triazoles/farmacología , Caspofungina , Humanos , Pruebas de Sensibilidad Microbiana , Sporothrix/clasificación , Sporothrix/aislamiento & purificación , Terbinafina
7.
Org Biomol Chem ; 15(22): 4882-4896, 2017 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-28537315

RESUMEN

Histone deacetylases (HDACs) play a crucial role in numerous biological processes and therefore are targeted in anticancer research and in the field of epigenetics. Dithienylethenes (DTEs) and fulgimides were functionalized with hydroxamic acids, which is a known moiety binding to zinc dependent HDACs, to gain photoswitchable HDAC inhibitors. The new DTE based inhibitors showed moderate photochromic properties in polar solvents and the inhibitory activity changes up to a factor of four. The photochromic performance of the prepared fulgimide inhibitors was very good, even in aqueous buffer. They achieved a maximum three-fold difference in inhibitory activity. Docking experiments using the crystal structures of the tested enzymes gave a rationale for the observed moderate differences in the activities of the inhibitors.


Asunto(s)
Etilenos/farmacología , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/metabolismo , Indoles/farmacología , Succinimidas/farmacología , Tiofenos/farmacología , Relación Dosis-Respuesta a Droga , Etilenos/síntesis química , Etilenos/química , Inhibidores de Histona Desacetilasas/síntesis química , Inhibidores de Histona Desacetilasas/química , Humanos , Indoles/síntesis química , Indoles/química , Estructura Molecular , Procesos Fotoquímicos , Relación Estructura-Actividad , Succinimidas/síntesis química , Succinimidas/química , Tiofenos/síntesis química , Tiofenos/química
8.
Phys Chem Chem Phys ; 18(35): 24325-31, 2016 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-27530608

RESUMEN

A new application of second harmonic light scattering to probe protein physisorption on a gold nanoparticle surface in aqueous buffer is reported. The free energies of adsorption, the number of protein molecules adsorbed on the surface and the binding affinity of a moderate size protein, alcohol dehydrogenase (ADH), and a small protein, insulin, have been determined using the change in the second harmonic scattered light signal as a function of binding. Four different size gold nanoparticles from 15 to 60 nm were used to determine the effect of size on the free energy change, the affinity constant and the number of protein molecules adsorbed on the surface. All were shown to increase with an increase in size. The binding can be reversed by centrifugation, and the protein molecules can be desorbed quantitatively. The application of this method for studying thermodynamic parameters of weakly interacting biomolecules with nanoparticles for nanoparticle based diagnostic and therapeutic formulations is important.

9.
Antimicrob Agents Chemother ; 59(10): 6615-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26248359

RESUMEN

This study aimed to explore any mutation in the CYP51 gene conferring azole resistance in Aspergillus flavus. Two voriconazole-resistant and 45 voriconazole-susceptible isolates were included in the study. Sequence analysis demonstrated a T1025C nucleotide change in CYP51C, resulting in the Y319H amino acid substitution in one resistant isolate. However, the earlier described T788G mutation in CYP51C conferring voriconazole resistance in A. flavus isolates was present in all isolates, irrespective of their susceptibility status.


Asunto(s)
Aspergillus flavus/efectos de los fármacos , Azoles/farmacología , Aspergillus flavus/genética , Farmacorresistencia Fúngica/genética , Proteínas Fúngicas/genética , Datos de Secuencia Molecular , Mutación , Voriconazol/farmacología
10.
Antimicrob Agents Chemother ; 59(3): 1745-50, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25583714

RESUMEN

Clinical breakpoints (CBPs) have not been established for the Mucorales and any antifungal agent. In lieu of CBPs, epidemiologic cutoff values (ECVs) are proposed for amphotericin B, posaconazole, and itraconazole and four Mucorales species. Wild-type (WT) MIC distributions (organisms in a species-drug combination with no detectable acquired resistance mechanisms) were defined with available pooled CLSI MICs from 14 laboratories (Argentina, Australia, Canada, Europe, India, Mexico, and the United States) as follows: 10 Apophysomyces variabilis, 32 Cunninghamella bertholletiae, 136 Lichtheimia corymbifera, 10 Mucor indicus, 123 M. circinelloides, 19 M. ramosissimus, 349 Rhizopus arrhizus, 146 R. microsporus, 33 Rhizomucor pusillus, and 36 Syncephalastrum racemosum isolates. CLSI broth microdilution MICs were aggregated for the analyses. ECVs comprising ≥95% and ≥97.5% of the modeled populations were as follows: amphotericin B ECVs for L. corymbifera were 1 and 2 µg/ml, those for M. circinelloides were 1 and 2 µg/ml, those for R. arrhizus were 2 and 4 µg/ml, and those for R. microsporus were 2 and 2 µg/ml, respectively; posaconazole ECVs for L. corymbifera were 1 and 2, those for M. circinelloides were 4 and 4, those for R. arrhizus were 1 and 2, and those for R. microsporus were 1 and 2, respectively; both itraconazole ECVs for R. arrhizus were 2 µg/ml. ECVs may aid in detecting emerging resistance or isolates with reduced susceptibility (non-WT MICs) to the agents evaluated.


Asunto(s)
Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico , Farmacorresistencia Fúngica Múltiple/efectos de los fármacos , Itraconazol/uso terapéutico , Mucorales/efectos de los fármacos , Mucormicosis/tratamiento farmacológico , Triazoles/uso terapéutico , Humanos , Pruebas de Sensibilidad Microbiana
11.
Br J Anaesth ; 114(4): 588-97, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25571932

RESUMEN

INTRODUCTION: Postoperative nausea and vomiting (PONV) is frequently encountered in the surgical recovery room. Abdominal surgery is one important risk factor for increased incidence of PONV. Gabapentin, an anticonvulsant with known postoperative analgesic properties, has shown some activity against PONV. Results from clinical trials evaluating the anti-emetic efficacy of gabapentin are conflicting. The present meta-analysis was performed to examine this issue. METHODS: Seventeen randomized placebo-controlled trials reporting PONV with preoperative gabapentin administration in patients undergoing abdominal surgery were included for analysis. Outcomes evaluated were nausea, vomiting, composite PONV and the use of rescue anti-emetic medication in the postoperative period. RESULTS: The pooled relative risk (RR), estimated using the random effects model of the metafor package for R, was 0.76 (95% CI 0.58-0.98) for nausea, 0.62 (0.45-0.85) for vomiting, 0.71 (0.39-1.28) for data represented as composite PONV (possibly biased by a single study, as observed in the sensitivity analysis), and 0.6 (0.41-0.89) for rescue anti-emetic use. There was a significant RR reduction for nausea and vomiting when propofol was not used as induction and/or maintenance for anaesthesia. In the abdominal hysterectomy subgroup, there was a significant RR reduction for vomiting but not for nausea. DISCUSSION: The present analysis provides evidence supporting preoperative gabapentin as a pharmacotherapy for prevention of PONV in patients undergoing abdominal surgeries. Future studies comparing preoperative gabapentin with 5HT3 antagonists are needed to precisely define its role in PONV.


Asunto(s)
Abdomen/cirugía , Aminas/uso terapéutico , Ácidos Ciclohexanocarboxílicos/uso terapéutico , Náusea y Vómito Posoperatorios/prevención & control , Ácido gamma-Aminobutírico/uso terapéutico , Gabapentina , Humanos , Sesgo de Publicación
12.
Br J Cancer ; 111(12): 2351-60, 2014 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-25490678

RESUMEN

BACKGROUND: Male breast cancer (MBC) is still poorly understood with a large proportion arising in families with a history of breast cancer. Genomic studies have focused on germline determinants of MBC risk, with minimal knowledge of somatic changes in these cancers. METHODS: Using a TruSeq amplicon cancer panel, this study evaluated 48 familial MBCs (3 BRCA1 germline mutant, 17 BRCA2 germline mutant and 28 BRCAX) for hotspot somatic mutations and copy number changes in 48 common cancer genes. RESULTS: Twelve missense mutations included nine PIK3CA mutations (seven in BRCAX patients), two TP53 mutations (both in BRCA2 patients) and one PTEN mutation. Common gains were seen in GNAS (34.1%) and losses were seen in GNAQ (36.4%), ABL1 (47.7%) and ATM (34.1%). Gains of HRAS (37.5% vs 3%, P=0.006), STK11 (25.0% vs 0%, P=0.01) and SMARCB1 (18.8% vs 0%, P=0.04) and the loss of RB1 (43.8% vs 13%, P=0.03) were specific to BRCA2 tumours. CONCLUSIONS: This study is the first to perform high-throughput somatic sequencing on familial MBCs. Overall, PIK3CA mutations are most commonly seen, with fewer TP53 and PTEN mutations, similar to the profile seen in luminal A female breast cancers. Differences in mutation profiles and patterns of gene gains/losses are seen between BRCA2 (associated with TP53/PTEN mutations, loss of RB1 and gain of HRAS, STK11 and SMARCB1) and BRCAX (associated with PIK3CA mutations) tumours, suggesting that BRCA2 and BRCAX MBCs may be distinct and arise from different tumour pathways. This has implications on potential therapies, depending on the BRCA status of MBC patients.


Asunto(s)
Neoplasias de la Mama Masculina/genética , Genes p53 , Mutación , Fosfohidrolasa PTEN/genética , Proteína p53 Supresora de Tumor/genética , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama Masculina/enzimología , Neoplasias de la Mama Masculina/metabolismo , Análisis Mutacional de ADN , Femenino , Predisposición Genética a la Enfermedad , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino
13.
Clin Exp Allergy ; 43(8): 850-73, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23889240

RESUMEN

Allergic bronchopulmonary aspergillosis (ABPA) is an immunological pulmonary disorder caused by hypersensitivity to Aspergillus fumigatus, manifesting with poorly controlled asthma, recurrent pulmonary infiltrates and bronchiectasis. There are estimated to be in excess of four million patients affected world-wide. The importance of recognizing ABPA relates to the improvement of patient symptoms, and delay in development or prevention of bronchiectasis, one manifestation of permanent lung damage in ABPA. Environmental factors may not be the only pathogenetic factors because not all asthmatics develop ABPA despite being exposed to the same environment. Allergic bronchopulmonary aspergillosis is probably a polygenic disorder, which does not remit completely once expressed, although long-term remissions do occur. In a genetically predisposed individual, inhaled conidia of A. fumigatus germinate into hyphae with release of antigens that activate the innate and adaptive immune responses (Th2 CD4(+) T cell responses) of the lung. The International Society for Human and Animal Mycology (ISHAM) has constituted a working group on ABPA complicating asthma (www.abpaworkinggroup.org), which convened an international conference to summarize the current state of knowledge, and formulate consensus-based guidelines for diagnosis and therapy. New diagnosis and staging criteria for ABPA are proposed. Although a small number of randomized controlled trials have been conducted, long-term management remains poorly studied. Primary therapy consists of oral corticosteroids to control exacerbations, itraconazole as a steroid-sparing agent and optimized asthma therapy. Uncertainties surround the prevention and management of bronchiectasis, chronic pulmonary aspergillosis and aspergilloma as complications, concurrent rhinosinusitis and environmental control. There is need for new oral antifungal agents and immunomodulatory therapy.


Asunto(s)
Aspergilosis Broncopulmonar Alérgica/diagnóstico , Aspergilosis Broncopulmonar Alérgica/epidemiología , Aspergilosis Broncopulmonar Alérgica/etiología , Aspergilosis Broncopulmonar Alérgica/terapia , Humanos
15.
Persoonia ; 30: 11-47, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24027345

RESUMEN

The order Mucorales comprises predominantly fast-growing saprotrophic fungi, some of which are used for the fermentation of foodstuffs but it also includes species known to cause infections in patients with severe immune or metabolic impairments. To inventory biodiversity in Mucorales ITS barcodes of 668 strains in 203 taxa were generated covering more than two thirds of the recognised species. Using the ITS sequences, Molecular Operational Taxonomic Units were defined by a similarity threshold of 99 %. An LSU sequence was generated for each unit as well. Analysis of the LSU sequences revealed that conventional phenotypic classifications of the Mucoraceae are highly artificial. The LSU- and ITS-based trees suggest that characters, such as rhizoids and sporangiola, traditionally used in mucoralean taxonomy are plesiomorphic traits. The ITS region turned out to be an appropriate barcoding marker in Mucorales. It could be sequenced directly in 82 % of the strains and its variability was sufficient to resolve most of the morphospecies. Molecular identification turned out to be problematic only for the species complexes of Mucor circinelloides, M. flavus, M. piriformis and Zygorhynchus moelleri. As many as 12 possibly undescribed species were detected. Intraspecific variability differed widely among mucorealean species ranging from 0 % in Backusella circina to 13.3 % in Cunninghamella echinulata. A high proportion of clinical strains was included for molecular identification. Clinical isolates of Cunninghamella elegans were identified molecularly for the first time. As a result of the phylogenetic analyses several taxonomic and nomenclatural changes became necessary. The genus Backusella was emended to include all species with transitorily recurved sporangiophores. Since this matched molecular data all Mucor species possessing this character were transferred to Backusella. The genus Zygorhynchus was shown to be polyphyletic based on ITS and LSU data. Consequently, Zygorhynchus was abandoned and all species were reclassified in Mucor. Our phylogenetic analyses showed, furthermore, that all non-thermophilic Rhizomucor species belong to Mucor. Accordingly, Rhizomucor endophyticus was transferred to Mucor and Rhizomucor chlamydosporus was synonymised with Mucor indicus. Lecto-, epi- or neotypes were designated for several taxa.

16.
Langmuir ; 28(13): 5570-9, 2012 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-22385301

RESUMEN

This paper presents simulation studies of nanoparticle supercluster (NPSC) nucleation from a temperature quenched system. The nanoparticles are represented as 5 nm, spherical gold nanoparticles ligated with alkane thiols. The pair potential accounts for the van der Waals interaction between the metallic cores and ligand-ligand and ligand-solvent interactions. Phenomena well-known for molecular systems are observed including a prenucleation induction period, fluctuating prenucleation clusters that predominately add monomers one at a time, a critical nucleus size, and growth of NPSCs from solution in the presence of an equilibrium supernatant, all consistent with classical nucleation theory. However, only the largest prenucleating clusters are dense, and the cluster size can occasionally range greater than the critical size in the prenucleation regime until a cluster with low enough energy occurs, then nucleation ensues. Late in the nucleation process, the clusters display a crystalline structure that is a random mix of face-centered cubic (fcc) and hexagonal close-packed (hcp) lattices and indistinguishable from a randomized icosahedra structure.

17.
Langmuir ; 28(46): 16015-21, 2012 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-23072652

RESUMEN

Results from extensive Brownian dynamics simulations are presented for nucleation in a system of colloidal particles interacting via a short-range attractive potential. Our analysis shows that, even though the system is not in equilibrium, structures of small size clusters compare well with the theoretically predicted and experimentally observed ground state structures for short-range colloidal systems. In addition, the distribution of the symmetric structures in nucleation is comparable to the distribution seen in equilibrium. We also investigate how the shape and structure of fluctuating clusters in the prenucleation regime affect the formation of a stable nucleating cluster.

19.
J Hosp Infect ; 122: 173-179, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35124141

RESUMEN

BACKGROUND: An unprecedented rise in the number of COVID-19-associated mucormycosis (CAM) cases has been reported in India. Myriad hypotheses are proposed for the outbreak. We recently reported uncontrolled diabetes and inappropriate steroid therapy as significant risk factors for the outbreak. However, Mucorales contamination of hospital environment was not studied. AIM: To perform a multi-centre study across India to determine possible Mucorales contamination of hospital environment during the outbreak. METHODS: Eleven hospitals from four zones of India representing high to low incidence for mucormycosis cases were included in the study. Samples from a variety of equipment used by the patients and ambient air were collected during May 19th, 2021 through August 25th, 2021. FINDINGS: None of the hospital equipment sampled was contaminated with Mucorales. However, Mucorales were isolated from 11.1% air-conditioning vents and 1.7% of patients' used masks. Other fungi were isolated from 18% of hospital equipment and surfaces, and 8.1% of used masks. Mucorales grew from 21.7% indoor and 53.8% outdoor air samples. Spore counts of Mucorales in air were significantly higher in the hospitals of North and South zones compared to West and East zones (P < 0.0001). Among Mucorales isolated from the environment, Rhizopus spp. were the most frequent genus. CONCLUSION: Contamination of air-conditioning vents and hospital air by Mucorales was found. Presence of Mucorales in these areas demands regular surveillance and improvement of hospital environment, as contamination may contribute to healthcare-associated mucormycosis outbreaks, especially among immunocompromised patients.


Asunto(s)
COVID-19 , Mucorales , Mucormicosis , Brotes de Enfermedades , Hospitales , Humanos , India/epidemiología , Mucormicosis/epidemiología
20.
Biophys J ; 101(10): 2502-6, 2011 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-22098749

RESUMEN

We show that the kinetics of nanochain formation of amelogenin molecules is well described by a combination of translational and rotational diffusion of a simplified anisotropic bipolar model consisting of hydrophobic spherical colloid particles and a point charge located on each particle surface. The colloid particles interact via a standard depletion attraction whereas the point charges interact through a screened Coulomb repulsion. We study the kinetics via a Brownian dynamics simulation of both translational and rotational motions and show that the anisotropy brought in by the charge dramatically affects the kinetic pathway of cluster formation and our simple model captures the main features of the experimental observations.


Asunto(s)
Amelogenina/química , Sustancias Macromoleculares/química , Modelos Moleculares , Nanopartículas/química , Coloides/química , Cinética , Factores de Tiempo
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