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1.
Ultrasound Obstet Gynecol ; 63(3): 378-384, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-37594210

RESUMEN

OBJECTIVES: The association between pregestational diabetes mellitus (PDM) and risk of congenital heart disease (CHD) is well recognized; however, the importance of glycemic control and other coexisting risk factors during pregnancy is less clear. We sought to determine the relative risk (RR) of major CHD (mCHD) among offspring from pregnancies complicated by PDM and the effect of first-trimester glycemic control on mCHD risk. METHODS: We determined the incidence of mCHD (requiring surgery within 1 year of birth or resulting in pregnancy termination or fetal demise) among registered births in Alberta, Canada. Linkage of diabetes status, maximum hemoglobin A1c (HbA1c) at < 16 weeks' gestation and other covariates was performed using data from the Alberta Perinatal Health Program registry. Risk of mCHD according to HbA1c was estimated as an adjusted RR (aRR), calculated using log-binomial modeling. RESULTS: Of 1412 cases of mCHD in 594 773 (2.37/1000) births in the study period, mCHD was present in 48/7497 with PDM (6.4/1000; RR, 2.8 (95% CI, 2.1-3.7); P < 0.0001). In the entire cohort, increased maternal age (aRR, 1.03 (95% CI, 1.02-1.04); P < 0.0001) and multiple gestation (aRR, 1.37 (95% CI, 1.1-1.8); P = 0.02) were also associated with mCHD risk, whereas maternal prepregnancy weight > 91 kg was not. The stratified risk for mCHD associated with HbA1c ≤ 6.1%, > 6.1-8.0% and > 8.0% was 4.2/1000, 6.8/1000 and 17.1/1000 PDM/gestational diabetes mellitus births, respectively; the aRR of mCHD associated with PDM and HbA1c > 8.0% was 8.5 (95% CI, 5.0-14.4) compared to those without diabetes and 5.5 (95% CI, 1.6-19.4) compared to PDM with normal HbA1c (≤ 6.1%). CONCLUSIONS: PDM is associated with a RR of 2.8 for mCHD, increasing to 8.5 in those with HbA1c > 8%. These data should facilitate refinement of referral indications for high-risk pregnancy screening. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Aborto Inducido , Diabetes Gestacional , Cardiopatías Congénitas , Femenino , Embarazo , Humanos , Hemoglobina Glucada , Cardiopatías Congénitas/epidemiología , Factores de Riesgo
2.
Ultrasound Obstet Gynecol ; 60(3): 359-366, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35839119

RESUMEN

OBJECTIVE: Socioeconomic status (SES) and distance of residence from tertiary care may impact fetal detection of congenital heart disease (CHD), partly through reduced access to and quality of obstetric ultrasound screening. It is unknown whether SES and remoteness of residence (RoR) affect prenatal detection of CHD in jurisdictions with universal health coverage. We examined the impact of SES and RoR on the rate and timing of prenatal diagnosis of major CHD within the province of Alberta in Canada. METHODS: In this retrospective study, we identified all fetuses and infants diagnosed with major CHD in Alberta, from 2008 to 2018, that underwent cardiac surgical intervention within the first year after birth, died preoperatively, were stillborn or underwent termination. Using maternal residence postal code and geocoding, Chan SES index quintile, geographic distance from a tertiary-care fetal cardiology center and the Canadian Index of Remoteness (IoR) were calculated. Outcome measures included rates of prenatal diagnosis and diagnosis after 22 weeks' gestation. Risk ratios (RR) were calculated using log-binomial regression and stratified by rural (≥ 100 km from tertiary care) or metropolitan (< 100 km from tertiary care) residence, adjusting for year of birth and the obstetric ultrasound screening view in which CHD would most likely be detected (four-chamber view; outflow-tract view; three-vessel or three-vessels-and-trachea or non-standard view; septal view). RESULTS: Of 1405 fetuses/infants with major CHD, prenatal diagnosis occurred in 814 (57.9%). Residence ≥ 100 km from tertiary care (adjusted RR, 1.19; 95% CI, 1.05-1.34) and higher IoR (adjusted RR, 1.9; 95% CI, 1.1-3.3) were associated with missed prenatal diagnosis of major CHD. Similarly, residence ≥ 100 km from tertiary care (adjusted RR, 1.41; 95% CI, 1.22-1.62) and higher IoR (adjusted RR, 3.6; 95% CI, 2.2-8.2) were associated with prenatal diagnosis after 22 weeks. Although adjusted and unadjusted analyses showed no association between Chan SES index quintile and prenatal-diagnosis rate overall nor for residence in rural areas, in metropolitan regions, lower SES quintiles were associated with missed prenatal diagnosis (quintile 1: RR, 1.24; 95% CI, 1.02-1.50) and higher risk of diagnosis after 22 weeks' gestation (quintile 1: RR, 1.46; 95% CI, 1.10-1.93; quintile 2: RR, 1.66; 95% CI, 1.24-2.23). CONCLUSIONS: Despite universal healthcare, rural residence in Alberta is associated with lower rate of prenatal diagnosis of major CHD and higher risk of late prenatal diagnosis (≥ 22 weeks). Within metropolitan regions, lower SES impacts negatively prenatal-diagnosis rate and timing. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Cardiopatías Congénitas , Cobertura Universal del Seguro de Salud , Alberta/epidemiología , Femenino , Cardiopatías Congénitas/diagnóstico por imagen , Cardiopatías Congénitas/epidemiología , Humanos , Lactante , Embarazo , Estudios Retrospectivos , Clase Social , Ultrasonografía Prenatal
3.
Clin Exp Immunol ; 203(1): 13-21, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32852779

RESUMEN

Anti-Ro60 is one of the most common and clinically important serum autoantibodies that has a number of diagnostic and predictive capabilities. Most diagnostic laboratories report this simply as a qualitative positive/negative result. The objective of this study was to examine the clinical and serological relevance of a novel subset of anti-Ro60 in patients who display low levels of anti-Ro60 (anti-Ro60low ). We retrospectively identified anti-Ro60 sera during a 12-month period at a major immunopathology diagnostic laboratory in Australia. These all were anti-Ro60-precipitin-positive on the diagnostic gold standard counter-immuno-electrophoresis (CIEP). Lineblot immunoassay was used to stratify patients into either anti-Ro60low or anti-Ro60high subsets. We compared the medical and laboratory parameters associated with each group. Enzyme-linked immunosorbent assay (ELISA) and mass spectrometry techniques were used to analyse the serological and molecular basis behind the two subsets. Anti-Ro60low patients displayed less serological activity than anti-Ro60high patients with less intermolecular spreading, hypergammaglobulinaemia and less tendency to undergo anti-Ro60 isotype-switching than anti-Ro60high patients. Mass spectrometric typing of the anti-Ro60low subset showed restricted variable heavy chain subfamily usage and amino acid point mutations. This subset also displayed clinical relevance, being present in a number of patients with systemic autoimmune rheumatic diseases (SARD). We identify a novel anti-Ro60low patient subset that is distinct from anti-Ro60high patients serologically and molecularly. It is not clear whether they arise from common or separate origins; however, they probably have different developmental pathways to account for the stark difference in immunological maturity. We hence demonstrate significance to anti-Ro60low and justify accurate detection in the diagnostic laboratory.


Asunto(s)
Anticuerpos Antinucleares , Autoantígenos , Enfermedades Autoinmunes , ARN Citoplasmático Pequeño , Ribonucleoproteínas , Anticuerpos Antinucleares/sangre , Anticuerpos Antinucleares/inmunología , Australia , Autoantígenos/sangre , Autoantígenos/inmunología , Enfermedades Autoinmunes/sangre , Enfermedades Autoinmunes/inmunología , Ensayo de Inmunoadsorción Enzimática , Humanos , Células K562 , ARN Citoplasmático Pequeño/sangre , ARN Citoplasmático Pequeño/inmunología , Ribonucleoproteínas/sangre , Ribonucleoproteínas/inmunología
4.
Mol Psychiatry ; 25(8): 1651-1672, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31792364

RESUMEN

Short-term memory dysfunction is a key early feature of Alzheimer's disease (AD). Psychiatric patients may be at higher risk for memory dysfunction and subsequent AD due to the negative effects of stress and depression on the brain. We carried out longitudinal within-subject studies in male and female psychiatric patients to discover blood gene expression biomarkers that track short term memory as measured by the retention measure in the Hopkins Verbal Learning Test. These biomarkers were subsequently prioritized with a convergent functional genomics approach using previous evidence in the field implicating them in AD. The top candidate biomarkers were then tested in an independent cohort for ability to predict state short-term memory, and trait future positive neuropsychological testing for cognitive impairment. The best overall evidence was for a series of new, as well as some previously known genes, which are now newly shown to have functional evidence in humans as blood biomarkers: RAB7A, NPC2, TGFB1, GAP43, ARSB, PER1, GUSB, and MAPT. Additional top blood biomarkers include GSK3B, PTGS2, APOE, BACE1, PSEN1, and TREM2, well known genes implicated in AD by previous brain and genetic studies, in humans and animal models, which serve as reassuring de facto positive controls for our whole-genome gene expression discovery approach. Biological pathway analyses implicate LXR/RXR activation, neuroinflammation, atherosclerosis signaling, and amyloid processing. Co-directionality of expression data provide new mechanistic insights that are consistent with a compensatory/scarring scenario for brain pathological changes. A majority of top biomarkers also have evidence for involvement in other psychiatric disorders, particularly stress, providing a molecular basis for clinical co-morbidity and for stress as an early precipitant/risk factor. Some of them are modulated by existing drugs, such as antidepressants, lithium and omega-3 fatty acids. Other drug and nutraceutical leads were identified through bioinformatic drug repurposing analyses (such as pioglitazone, levonorgestrel, salsolidine, ginkgolide A, and icariin). Our work contributes to the overall pathophysiological understanding of memory disorders and AD. It also opens new avenues for precision medicine- diagnostics (assement of risk) as well as early treatment (pharmacogenomically informed, personalized, and preventive).


Asunto(s)
Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/diagnóstico , Biomarcadores/sangre , Reposicionamiento de Medicamentos , Diagnóstico Precoz , Trastornos de la Memoria/sangre , Memoria a Corto Plazo , Farmacocinética , Adulto , Anciano , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Animales , Femenino , Humanos , Masculino , Trastornos de la Memoria/diagnóstico , Trastornos de la Memoria/tratamiento farmacológico , Trastornos de la Memoria/metabolismo , Persona de Mediana Edad , Adulto Joven
5.
Br J Surg ; 107(10): 1262-1280, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32395837

RESUMEN

BACKGROUND: Surgeons need guidance regarding appropriate personal protective equipment (PPE) during the COVID-19 pandemic based on scientific evidence rather than availability. The aim of this article is to inform surgeons of appropriate PPE requirements, and to discuss usage, availability, rationing and future solutions. METHODS: A systematic review was undertaken in accordance with PRISMA guidelines using MEDLINE, Embase and WHO COVID-19 databases. Newspaper and internet article sources were identified using Nexis. The search was complemented by bibliographic secondary linkage. The findings were analysed alongside guidelines from the WHO, Public Health England, the Royal College of Surgeons and specialty associations. RESULTS: Of a total 1329 articles identified, 95 studies met the inclusion criteria. Recommendations made by the WHO regarding the use of PPE in the COVID-19 pandemic have evolved alongside emerging evidence. Medical resources including PPE have been rapidly overwhelmed. There has been a global effort to overcome this by combining the most effective use of existing PPE with innovative strategies to produce more. Practical advice on all aspects of PPE is detailed in this systematic review. CONCLUSION: Although there is a need to balance limited supplies with staff and patient safety, this should not leave surgeons treating patients with inadequate PPE.


Asunto(s)
COVID-19/prevención & control , Asignación de Recursos para la Atención de Salud , Control de Infecciones/instrumentación , Equipo de Protección Personal/provisión & distribución , Pautas de la Práctica en Medicina , Cirujanos , COVID-19/epidemiología , Salud Global , Humanos , Control de Infecciones/métodos , Pandemias
6.
J Appl Microbiol ; 128(5): 1400-1413, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31841255

RESUMEN

AIMS: This study aimed at isolating endophytic fungi from Citrus limon (L.) possessing antioxidative and genoprotective potential. METHODS AND RESULTS: Endophytic fungi were screened for antioxidant activity using 2,2-diphenyl,1-picryl hydrazyl radical scavenging assay and maximum activity (79·70%) was exhibited by culture MP1 identified to be Penicillium oxalicum on the basis of morphological and molecular characteristics. The ethyl acetate extract of MP1 was subjected to silica column chromatography followed by LH 20 column chromatography for purification of active metabolites. The partially purified active fraction of P. oxalicum MP1 possessed good antioxidant activity as detected using various assays. It also exhibited a strong DNA damage protection potential on pUC19 plasmid DNA treated with Fenton reagent. On exposure to active fraction of MP1 significant reduction (P < 0·05) in nuclear deformities (like nuclear buds, micronuclei, nuclear ridges and binucleated cells) was observed in human lymphocytes pretreated with a toxic concentration of H2 O2 . In vivo genoprotectivity studies were conducted in fresh water fish Channa punctatus pretreated with a damaging compound 4-nonyl phenol. The active fraction of P. oxalicum MP1 caused a reduction of 94·7 and 66·60% in micronuclei and aberrant cell formation, respectively. A significant reduction (P < 0·05) in tail length and tail DNA parameters was also observed in comet assay. CONCLUSION: The endophytic P. oxalicum isolated in this study has the potential to produce metabolites possessing antioxidant and genoprotective activities. SIGNIFICANCE AND IMPACT OF THE STUDY: The isolated culture can be exploited in the field of therapeutics by virtue of its in vitro and in vivo genoprotective potential.


Asunto(s)
Antimutagênicos/metabolismo , Antioxidantes/metabolismo , Citrus/microbiología , Penicillium/aislamiento & purificación , Penicillium/metabolismo , Animales , Antimutagênicos/farmacología , Antioxidantes/farmacología , Daño del ADN/efectos de los fármacos , Endófitos , Humanos , Penicillium/clasificación
7.
J Appl Microbiol ; 126(3): 881-893, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30216609

RESUMEN

AIM: Recent concerns about the possible adverse effects of agricultural chemicals on health and environment have generated a considerable interest in biological alternatives. This study aimed to test the insecticidal potential of fungus Aspergillus flavus and revealed its genotoxic and cytotoxic effects using Spodoptera litura (Fabricius) as a model. METHODS AND RESULTS: The fungus was isolated from the surface of the dead insect and investigated for its insecticidal potential against S. litura by bioassay studies. Significant increase in mortality, prolonged development period and reduced adult emergence in S. litura were observed in larva fed on diet supplemented with fungal extract. In addition, fungus was also found to cause oxidative stress, DNA damage and cell death. Significantly higher percentages of necrotic cells and DNA damage were observed in larvae treated with fungal extract. Furthermore, DNA repair studies predicted the longevity of toxic effects induced by fungus. Phytochemical and ultra-high performance liquid chromatography studies revealed the presence of phenolic compounds in the extract and liquid chromatography-mass spectrometry indicated it to be a non-aflatoxin strain of A. flavus. Fungal extract was less toxic to mammalian cell lines as compared to cytotoxic drug doxorubicin (DOX) in the MTT assay. CONCLUSION: The study highlights the insecticidal potential of A. flavus by revealing its genotoxicity and cytotoxicity causing potential. This is the first report showing the genotoxic and cytotoxic effects of the fungus A. flavus on S. litura. SIGNIFICANCE AND IMPACT OF THE STUDY: The study provides a useful insight to explore microbial agents as biopesticides in order to reduce various environmental as well as human health problems due to synthetic pesticides.


Asunto(s)
Aspergillus flavus , Productos Biológicos/toxicidad , Citotoxinas/toxicidad , Mutágenos/toxicidad , Spodoptera/efectos de los fármacos , Acetatos , Animales , Larva/efectos de los fármacos
8.
Bull Entomol Res ; 109(4): 550-558, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30567617

RESUMEN

The melon fruit fly, Bactrocera cucurbitae (Coquillett), is a serious agricultural pest which has defied the various control measures employed against it. Protease inhibitors present in plants which have the potential to inhibit the growth and development of associated insect pests can be a possible alternative which can be manipulated for developing resistance in plants to the pest. In the present study, winged bean (Psophocarpus tetragonolobus) protease inhibitor isolated through affinity chromatography was explored for its potential to disrupt the development of melon fruit fly, B. cucurbitae. Different concentrations (12.5, 25, 50, 100, 200, and 400 µg ml-1) of the winged bean protease inhibitor (WBPI) were incorporated into the artificial diet of the second instar (64-72 h old) larvae of B. cucurbitae. The WBPI significantly delayed the larval, pupal, and total development period. The percentage pupation and adult emergence of the treated larvae was reduced as compared with control. The activities of major digestive enzymes (trypsin, chymotrypsin, leucine aminopeptidase, and elastase) decreased significantly in the larvae treated with different concentrations (50, 100, 200, and 400 µg ml-1) of WBPI. The findings reveal that the inhibitor holds considerable promise for the management of the melon fruit fly.


Asunto(s)
Antibiosis , Fabaceae/química , Proteínas de Plantas/efectos adversos , Inhibidores de Proteasas/efectos adversos , Tephritidae/efectos de los fármacos , Animales , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Pupa/efectos de los fármacos , Pupa/crecimiento & desarrollo , Tephritidae/crecimiento & desarrollo
9.
Drug Dev Ind Pharm ; 45(2): 323-332, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30404554

RESUMEN

Betamethsone valerate (BMV), a medium potency topical corticosteroid, is one of the most commonly employed pharmacological agents for the management of atopic dermatitis in both adults and children. Despite having remarkable pharmacological efficacy, these agents have limited clinical implication due to poor penetration across the startum cornum (SC). To mitigate issues related to targeted delivery, stability, and solubility as well as to potentiate therapeutic and clinical implication, the nanodelivery systems have gained remarkable recognition. Therefore, this study was aimed to encapsulate BMV into the chitosan nanoparticles (CS-NPs) for optimum dermal targeting and improved penetration across the SC. The prepared NPs were characterized for particle size, zeta potential, polydispersity index, entrapment efficiency, loading capacity, crystallinity, thermal behavior, morphology, in vitro release kinetics, drug permeation across the SC, and percentage of drug retained into various skin layers. Results showed that optimized BMV-CS-NPs exhibited optimum physicochemical characteristics including small particle size (< 250 ± 28 nm), higher zeta potential (+58 ± 8 mV), and high entrapment efficiency (86 ± 5.6%) and loading capacity (34 ± 7.2%). The in vitro release study revealed that BMV-CS-NPs displayed Fickian-diffusion type mechanism of release in simulated skin surface (pH 5.5). Drug permeation efficiency and the amount of BMV retained into the epidermis and the dermis were comparatively higher in case of BMV-CS-NPs compared to BMV solution. Conclusively, we anticipated that BMV-CS-NPs could be a promising nanodelivery system for efficient dermal targeting of BMV and improved anti-AD efficacy.


Asunto(s)
Antiinflamatorios/administración & dosificación , Valerato de Betametasona/administración & dosificación , Administración Tópica , Animales , Antiinflamatorios/química , Valerato de Betametasona/química , Quitosano , Dermatitis Atópica/tratamiento farmacológico , Composición de Medicamentos , Sistemas de Liberación de Medicamentos , Tamaño de la Partícula , Presión , Ratas , Ratas Wistar , Piel/efectos de los fármacos , Solventes
10.
J Appl Microbiol ; 125(5): 1455-1465, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29877011

RESUMEN

AIM: The present study aimed to isolate and screen endophytes from Trachyspermum ammi with the ability to inhibit alpha glucosidase enzyme and evaluate their insecticidal potential. METHODS AND RESULTS: Endophytic fungi isolated from T. ammi were screened for alpha glucosidase inhibitory activity. Maximum inhibition (96%) was observed in an isolate AZ-9, identified to be Exophiala spinifera on morphological and molecular basis. Production of fungal metabolites was carried out in malt extract broth followed by extraction with ethyl acetate. Brown coloured gummy residue obtained after evaporation of ethyl acetate was partially soluble in water yielding white precipitates. The precipitate exhibiting α-glucosidase inhibitory activity was purified by repeated washing and centrifugation. The insecticidal activity of inhibitor was evaluated on Spodoptera litura (Fab.) by feeding this pest on diet amended with inhibitor. It resulted in significant larval mortality as well as deformities in emerging adults. A reduction in vivo digestive enzyme activity was also observed. Nutritional analysis revealed the toxic effect of AZ-9 inhibitor on various food utilization parameters of S. litura. A significant reduction was recorded in relative growth and consumption rate of S. litura. CONCLUSIONS: This is the first report on production of an alpha glucosidase inhibitor from E. spinifera with insecticidal activity. SIGNIFICANCE AND IMPACT OF THE STUDY: The study highlights the importance of endophytes in providing protection against insect pests to the host. It also suggests the insecticidal potential of alpha glucosidase inhibitor from E. spinifera against polyphagous pest S. litura.


Asunto(s)
Exophiala/química , Inhibidores de Glicósido Hidrolasas , Insecticidas , Spodoptera , Animales , Endófitos/química , Exophiala/metabolismo , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Larva , Pruebas de Toxicidad , alfa-Glucosidasas/metabolismo
11.
Am J Transplant ; 17(3): 657-670, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27500470

RESUMEN

Although stable mixed-hematopoietic chimerism induces robust immune tolerance to solid organ allografts in mice, the translation of this strategy to large animal models and to patients has been challenging. We have previously shown that in MHC-matched nonhuman primates (NHPs), a busulfan plus combined belatacept and anti-CD154-based regimen could induce long-lived myeloid chimerism, but without T cell chimerism. In that setting, donor chimerism was eventually rejected, and tolerance to skin allografts was not achieved. Here, we describe an adaptation of this strategy, with the addition of low-dose total body irradiation to our conditioning regimen. This strategy has successfully induced multilineage hematopoietic chimerism in MHC-matched transplants that was stable for as long as 24 months posttransplant, the entire length of analysis. High-level T cell chimerism was achieved and associated with significant donor-specific prolongation of skin graft acceptance. However, we also observed significant infectious toxicities, prominently including cytomegalovirus (CMV) reactivation and end-organ disease in the setting of functional defects in anti-CMV T cell immunity. These results underscore the significant benefits that multilineage chimerism-induction approaches may represent to transplant patients as well as the inherent risks, and they emphasize the precision with which a clinically successful regimen will need to be formulated and then validated in NHP models.


Asunto(s)
Infecciones por Citomegalovirus/complicaciones , Citomegalovirus/inmunología , Trasplante de Piel , Linfocitos T/inmunología , Quimera por Trasplante/inmunología , Tolerancia al Trasplante/inmunología , Activación Viral/inmunología , Animales , Enfermedades Transmisibles/etiología , Enfermedades Transmisibles/patología , Infecciones por Citomegalovirus/inmunología , Infecciones por Citomegalovirus/virología , Supervivencia de Injerto , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/patología , Trasplante de Células Madre Hematopoyéticas , Macaca mulatta , Acondicionamiento Pretrasplante , Trasplante Homólogo
12.
Biomacromolecules ; 18(7): 2013-2023, 2017 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-28535062

RESUMEN

The self-assembly in aqueous solution of three lipopeptides comprising a bioactive motif conjugated at the N terminus to dodecyl, tetradecyl or hexadecyl lipid chains has been examined. The bioactive motif is the peptide block YEALRVANEVTLN; a C-terminal fragment of the lumican proteoglycan. This study was motivated by our previous studies on the hexadecyl homologue C16-YEALRVANEVTLN, which showed aggregation into ß-sheet structures above a critical aggregation concentration (cac), but most remarkably, we found that these aggregates were stable to dilution below the cac.1 Here we find that the C12- and C14-homologues also self-assemble above a cac into ß-sheet nanotapes based on bilayer packing. The cac decreases with increasing lipopeptide hydrophobicity. Unexpectedly, the ß-sheet secondary structure is present upon dilution and the aggregates are thermally stable. These results indicate that the dilution trapping of ß-sheet secondary structure is not associated with lipid chain melting behavior. Instead, we associate it with pH-dependent favorable intermolecular electrostatic interactions. Investigation of the pH-dependence of aggregation led to the discovery of conditions for formation of lipopeptide hydrogels (initial sample preparation at pH 10 in NaOH solution, followed by reduction to pH ∼ 1 by addition of HCl). The lipopeptide hydrogels comprise networks of bilayer-based peptide nanotape bundles and to our knowledge this type of hydrogel is unprecedented. These hydrogels may have future applications based on processes such as encapsulation and release that involve fast switches between solution and hydrogel nanostructures.


Asunto(s)
Hidrogeles/química , Hidrogeles/síntesis química , Lipopéptidos/química , Concentración de Iones de Hidrógeno , Estructura Secundaria de Proteína
14.
Niger J Clin Pract ; 20(6): 774-776, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28656935

RESUMEN

Hamartomatous polyps of the tonsil are rare. They have been described using various terms such as a lymphangiomatous polyp, lymphangiectatic fibrous polyp, lipomatous polyp, or pedunculated tonsil; hence, the actual incidence is difficult to be quantified. Polyp of the palatine tonsils is an unusual benign lesion of the head and neck. It is a rare polypoidal mass that generally arises from a pedicle attached to the tonsil and projecting into the oropharynx. Polypoid lesions of the head and neck are likewise rare, and such tumors arising from the palatine tonsils are sparse. Tonsillar polyp is an uncommon hamartomatous lesion that generally arises from the tonsillar surface. It has rarely been reported in the medical literature. We present a case of hamartomatous polyp of the palatine tonsil in a 17-year-old male patient.


Asunto(s)
Hamartoma/patología , Tonsila Palatina , Pólipos/patología , Adolescente , Hamartoma/cirugía , Humanos , Masculino , Pólipos/cirugía
15.
Niger J Clin Pract ; 20(10): 1233-1236, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29192624

RESUMEN

OBJECTIVE: The aim of the study was to study the closure of dry central type of tympanic membrane perforations by chemical cautery and improvement of hearing, to analyse the effect of Gelfoam on nonhealing small tympanic membrane perforations, and to examine the relevance of conservative means of closure of tympanic membrane perforations as an office procedure. MATERIALS AND METHODS: In this study, 100 patients attending the outpatient department were enrolled. Cautery of perforation margin was carried out with 50% trichloroacetic acid (TCA). After cautery, in small perforations less than 4 mm, a small piece of Gelfoam larger than the size of perforation was cut, impregnated with corticosteroid ointment, and carefully placed over the cauterized area under endoscopic visualization. In slightly larger perforations, that is, between 4 and 5 mm, after applying TCA to the margins of the perforation, a piece of Gelfoam larger than the size of perforation was soaked with corticosteroid ointment and placed in the middle ear cavity. RESULTS: Patients had relief from various symptoms, such as tinnitus, heaviness, and so on. There was some amount of auditory improvement in almost all the cases. It ranged from 5 to 23 dB. CONCLUSIONS: Cautery and patching of tympanic membrane perforation may be considered as the first-line management in the small- to medium-sized perforations before attempting the surgical closure.


Asunto(s)
Corticoesteroides/uso terapéutico , Cauterización , Pomadas , Ácido Tricloroacético/uso terapéutico , Perforación de la Membrana Timpánica/cirugía , Adulto , Endoscopía , Femenino , Esponja de Gelatina Absorbible , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
16.
J Appl Microbiol ; 120(2): 301-11, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26544796

RESUMEN

AIM: To exploit the potential of endophytic fungi for pharmaceutically important antidiabetic alpha glycosidase inhibitors. METHODS AND RESULTS: Thirty six endophytic fungi were isolated from Acacia nilotica and screened for the production of alpha amylase and glucosidase inhibitors. Inhibitory activity against both alpha amylase (81%) and alpha glucosidase (80%) was exhibited in an isolate, identified to be Aspergillus awamori. Purification of the inhibitor was carried out on Sephadex LH-20 column and semi prep HPLC. The inhibitor was characterized to be proteinaceous in nature with an approximate molecular mass of 22 kDa. UHPLC amino acid analysis indicated the presence of amino acids serine, threonine, tyrosine and valine in the peptide. The purified inhibitor exhibited mixed type of inhibition against alpha amylase and alpha glucosidase with IC50 values of 3·75 and 5·625 µg ml(-1) respectively. The inhibitor was stable over a wide range of pH and temperature. Optimization of process parameters to increase the yield of the inhibitor was undertaken using one factor at a time approach as well as RSM statistical analysis. The interaction of dextrose and proteose peptone for the test organism was significant with first order effect of pH. Increase of 13% was obtained in the inhibitory activity after optimization of process parameters. Mutagenicity testing by Ames test revealed nonmutagenic nature of the peptide. CONCLUSION: Endophytic A. awamori is capable of producing a peptide with alpha glycosidase inhibitory activity. SIGNIFICANCE AND IMPACT OF THE STUDY: The inhibitor obtained in this study possesses dual (alpha glucosidase and alpha amylase) inhibitory activity, low IC50 values, is highly stable under extreme conditions of pH and temperature, and is nonmutagenic in nature. By virtue of its properties it can be commercially produced and exploited for better management of diabetes.


Asunto(s)
Acacia/microbiología , Aspergillus/química , Diabetes Mellitus/tratamiento farmacológico , Endófitos/química , Inhibidores Enzimáticos/farmacología , Hipoglucemiantes/farmacología , Péptidos/farmacología , Aspergillus/clasificación , Aspergillus/aislamiento & purificación , Aspergillus/metabolismo , Diabetes Mellitus/enzimología , Endófitos/clasificación , Endófitos/aislamiento & purificación , Endófitos/metabolismo , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Inhibidores Enzimáticos/metabolismo , Humanos , Hipoglucemiantes/química , Hipoglucemiantes/aislamiento & purificación , Hipoglucemiantes/metabolismo , Péptidos/química , Péptidos/aislamiento & purificación , Péptidos/metabolismo , Filogenia , alfa-Amilasas/antagonistas & inhibidores , alfa-Amilasas/metabolismo
17.
J Appl Microbiol ; 121(4): 1015-25, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27248836

RESUMEN

AIMS: The aim of this study was to screen endophytic fungi isolated from Vinca rosea for their potential to produce acetylcholinesterase (AChE) inhibitors. METHOD AND RESULTS: Endophytic fungi isolated from V. rosea (Catharanthus roseus), were screened for AChE inhibitor production using Ellman's method. Maximum inhibition against AChE (78%) was observed in an isolate VS-10, identified to be Alternaria alternata on morphological and molecular basis. The isolate also inhibited butyrylcholinesterase (73%). Significant increase (1·3 fold) was achieved after optimization of process parameters using one variable at time approach. The inhibitor was purified using chromatographic techniques. The structure elucidation of the inhibitor was carried out using spectroscopic techniques and was identified to be 'altenuene'. The purified inhibitor possessed antioxidant potential as revealed by dot blot assay. The insecticidal potential of purified inhibitor was evaluated by feeding Spodoptora litura on diet amended with inhibitor. It evinced significant larval mortality. CONCLUSIONS: Endophytic A. alternata can serve as a source of dual cholinesterase inhibitor 'altenuene' with significant antioxidant and insecticidal activity. This is the first report on acetylcholinestearse inhibitory activity of altenuene. SIGNIFICANCE AND IMPACT OF THE STUDY: Alternaria alternata has the potential to produce a dual ChE inhibitor with antioxidant activity useful in the treatment of neurodegenerative disorders and in agriculture as biocontrol agent.


Asunto(s)
Alternaria/química , Catharanthus/microbiología , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/aislamiento & purificación , Endófitos/química , Proteínas de Insectos/antagonistas & inhibidores , Insecticidas/química , Lactonas/química , Alternaria/aislamiento & purificación , Alternaria/metabolismo , Animales , Inhibidores de la Colinesterasa/metabolismo , Inhibidores de la Colinesterasa/farmacología , Colinesterasas/química , Colinesterasas/metabolismo , Endófitos/aislamiento & purificación , Endófitos/metabolismo , Proteínas de Insectos/metabolismo , Insecticidas/aislamiento & purificación , Insecticidas/farmacología , Lactonas/aislamiento & purificación , Lactonas/metabolismo , Lactonas/farmacología , Spodoptera/efectos de los fármacos , Spodoptera/enzimología
18.
Med J Malaysia ; 71(3): 117-21, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27495884

RESUMEN

INTRODUCTION: bacteremia continues to be one of the major causes of morbidity and mortality despite the existence of numerous antimicrobial agents. this study aimed to provide a Malaysian perspective on paediatric community-acquired bacteraemia based on the documentation of epidemiology and antimicrobial profile of the isolated pathogens. METHOD: A retrospective study was conducted by analysing clinical details, blood cultures and antimicrobial susceptibility testing results in children between the ages of 0 to 13 years old, who were admitted to selayang Hospital over an 11-year period from 2001 until 2011. there were 222 bacteraemia cases and the median age was 11.7 months. the highest number (39%) of bacteraemia cases occurred between ages one month to one year. the three most commonly isolated aetiological agents were Staphylococcus aureus (17.1%), nontyphoidal Salmonella (16.2%), and Streptococcus pneumoniae (12.6%). Almost 8% of the Staphylococcus aureus isolates were methicillin resistant, while nontyphoidal Salmonella (Nts) isolates demonstrated 18.4%, 10.5% and 2.6% resistance towards ampicillin, trimethoprim-sulfamethoxazole and ciprofloxacin respectively. All Nts isolates were sensitive to ceftriaxone. Streptococcus pneumoniae isolates showed 17.9% resistance to penicillin. skin and soft tissue infections as well as lower respiratory tract infections (63.2%) were the main foci of infections in Staphylococcus aureus bacteraemia. Acute gastroenteritis (80.0%) and pneumonia (60.8%) were the main presentations of Nts and Streptococcus pneumoniae bacteraemia respectively. Overall mortality rate was 8.1%. CONCLUSION: Knowledge on the local epidemiology and antibiotic resistance pattern serves as a significant platform in improving the empiric antibiotic therapy for patients with community acquired bacteraemia.


Asunto(s)
Bacteriemia/epidemiología , Infecciones Comunitarias Adquiridas/epidemiología , Farmacorresistencia Bacteriana , Centros de Atención Terciaria/estadística & datos numéricos , Adolescente , Antibacterianos , Niño , Preescolar , Humanos , Lactante , Malasia , Pruebas de Sensibilidad Microbiana , Estudios Retrospectivos , Staphylococcus aureus/aislamiento & purificación
19.
J Virol ; 88(9): 4721-35, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24522914

RESUMEN

UNLABELLED: The impact of Epstein-Barr virus (EBV) on human health is substantial, but vaccines that prevent primary EBV infections or treat EBV-associated diseases are not yet available. The Epstein-Barr nuclear antigen 1 (EBNA-1) is an important target for vaccination because it is the only protein expressed in all EBV-associated malignancies. We have designed and tested two therapeutic EBV vaccines that target the rhesus (rh) lymphocryptovirus (LCV) EBNA-1 to determine if ongoing T cell responses during persistent rhLCV infection in rhesus macaques can be expanded upon vaccination. Vaccines were based on two serotypes of E1-deleted simian adenovirus and were administered in a prime-boost regimen. To further modulate the response, rhEBNA-1 was fused to herpes simplex virus glycoprotein D (HSV-gD), which acts to block an inhibitory signaling pathway during T cell activation. We found that vaccines expressing rhEBNA-1 with or without functional HSV-gD led to expansion of rhEBNA-1-specific CD8(+) and CD4(+) T cells in 33% and 83% of the vaccinated animals, respectively. Additional animals developed significant changes within T cell subsets without changes in total numbers. Vaccination did not increase T cell responses to rhBZLF-1, an immediate early lytic phase antigen of rhLCV, thus indicating that increases of rhEBNA-1-specific responses were a direct result of vaccination. Vaccine-induced rhEBNA-1-specific T cells were highly functional and produced various combinations of cytokines as well as the cytolytic molecule granzyme B. These results serve as an important proof of principle that functional EBNA-1-specific T cells can be expanded by vaccination. IMPORTANCE: EBV is a common human pathogen that establishes a persistent infection through latency in B cells, where it occasionally reactivates. EBV infection is typically benign and is well controlled by the host adaptive immune system; however, it is considered carcinogenic due to its strong association with lymphoid and epithelial cell malignancies. Latent EBNA-1 is a promising target for a therapeutic vaccine, as it is the only antigen expressed in all EBV-associated malignancies. The goal was to determine if rhEBNA-1-specific T cells could be expanded upon vaccination of infected animals. Results were obtained with vaccines that target EBNA-1 of rhLCV, a virus closely related to EBV. We found that vaccination led to expansion of rhEBNA-1 immune cells that exhibited functions fit for controlling viral infection. This confirms that rhEBNA-1 is a suitable target for therapeutic vaccines. Future work should aim to generate more-robust T cell responses through modified vaccines.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Infecciones por Herpesviridae/veterinaria , Vacunas contra Herpesvirus/inmunología , Lymphocryptovirus/inmunología , Proteínas Virales/inmunología , Adenovirus de los Simios/genética , Animales , Portadores de Fármacos , Femenino , Vectores Genéticos , Infecciones por Herpesviridae/inmunología , Vacunas contra Herpesvirus/administración & dosificación , Vacunas contra Herpesvirus/genética , Lymphocryptovirus/genética , Macaca mulatta , Vacunación/métodos , Proteínas Virales/genética
20.
Allergy ; 70(3): 302-9, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25495666

RESUMEN

BACKGROUND: Patients with asthma may be more susceptible to adverse events (AEs) with sublingual immunotherapy tablet (SLIT-tablet) treatment, such as severe systemic reactions and asthma-related events. Using data from eight trials of grass SLIT-tablet in subjects with allergic rhinitis with/without conjunctivitis (AR/C), AE frequencies were determined in adults and children with and without reported asthma. METHODS: Data from randomized, double-blind, placebo-controlled trials of Timothy grass SLIT-tablet MK-7243 (2800 BAU/75 000 SQ-T, Merck/ALK-Abelló) were pooled for post hoc analyses. Subjects with uncontrolled and severe asthma were excluded from the trials. Frequencies for treatment-emergent AEs (TEAEs), local allergic swelling (mouth or throat), systemic allergic reactions, and asthma-related treatment-related AEs (TRAEs) were calculated. RESULTS: Among adults (n = 3314) and children (n = 881), 24% and 31%, respectively, had reported asthma. No serious local allergic swellings or serious systemic allergic reactions occurred in subjects with asthma treated with SLIT-tablet. There was no evidence of increased TEAEs, systemic allergic reactions, or severe local allergic swellings in adults or children with asthma treated with grass SLIT-tablet versus subjects without asthma in or outside of pollen season. There were 6/120 asthma-related TRAEs assessed as severe with grass SLIT-tablet and 2/60 with placebo, without a consistent trend among subjects with and without asthma (5 and 3 events, respectively). CONCLUSIONS: In the AR/C subjects with reported well-controlled mild asthma included in these studies, grass SLIT-tablet did not increase TEAE frequency, severe local allergic swelling, or systemic allergic reactions versus subjects without asthma. There was no indication that treatment led to acute asthma worsening.


Asunto(s)
Alérgenos/inmunología , Asma/complicaciones , Conjuntivitis/complicaciones , Phleum/efectos adversos , Rinitis Alérgica/complicaciones , Rinitis Alérgica/terapia , Inmunoterapia Sublingual , Adolescente , Adulto , Anciano , Alérgenos/administración & dosificación , Alérgenos/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Pruebas de Función Respiratoria , Rinitis Alérgica/fisiopatología , Inmunoterapia Sublingual/efectos adversos , Resultado del Tratamiento , Adulto Joven
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