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1.
Ann Coloproctol ; 39(5): 402-409, 2023 Oct.
Article in English | MEDLINE | ID: mdl-35569837

ABSTRACT

PURPOSE: This study was performed to investigate the convergent validity, discriminative validity, and reliability of the Brazilian version of the low anterior resection syndrome (LARS) score in a population with low educational and socioeconomic levels. METHODS: The LARS score was translated into the Portuguese language by forward- and back-translation procedures. In total, 127 patients from a public hospital in Brazil completed the questionnaires. The convergent validity was tested by comparing the LARS score with the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core Module 30 (QLQ-C30) and with patients' self-reported quality of life. For the discriminative validity, we tested the ability of the score to differentiate among subgroups of patients regarding neoadjuvant radiotherapy, type of surgery, and tumor distance from the anal verge. The test-retest reliability was investigated in a subgroup of 36 patients who responded to the survey twice in 2 weeks. RESULTS: The LARS score demonstrated a strong correlation with 5 of 6 items from the EORTC QLQ-C30 (P<0.05) and good concordance with patients' self-reported quality of life (95.3%), confirming the convergent validity. The score was able to discriminate between subgroups of patients with different clinical characteristics related to LARS (P<0.001). The agreement between the test and retest showed that 86.1% of the patients remained in the same LARS category, and there was no significant difference between the LARS score numerical values (P=0.80), indicating good reliability overall. CONCLUSION: The Brazilian version of the LARS score is a valid and reliable instrument to assess postoperative bowel function in a population with low educational and socioeconomic levels.

2.
Annals of Coloproctology ; : 402-409, 2023.
Article in English | WPRIM (Western Pacific) | ID: wpr-999345

ABSTRACT

Purpose@#This study was performed to investigate the convergent validity, discriminative validity, and reliability of the Brazilian version of the low anterior resection syndrome (LARS) score in a population with low educational and socioeconomic levels. @*Methods@#The LARS score was translated into the Portuguese language by forward- and back-translation procedures. In total, 127 patients from a public hospital in Brazil completed the questionnaires. The convergent validity was tested by comparing the LARS score with the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core Module 30 (QLQ-C30) and with patients’ self-reported quality of life. For the discriminative validity, we tested the ability of the score to differentiate among subgroups of patients regarding neoadjuvant radiotherapy, type of surgery, and tumor distance from the anal verge. The test-retest reliability was investigated in a subgroup of 36 patients who responded to the survey twice in 2 weeks. @*Results@#The LARS score demonstrated a strong correlation with 5 of 6 items from the EORTC QLQ-C30 (P<0.05) and good concordance with patients’ self-reported quality of life (95.3%), confirming the convergent validity. The score was able to discriminate between subgroups of patients with different clinical characteristics related to LARS (P<0.001). The agreement between the test and retest showed that 86.1% of the patients remained in the same LARS category, and there was no significant difference between the LARS score numerical values (P=0.80), indicating good reliability overall. @*Conclusion@#The Brazilian version of the LARS score is a valid and reliable instrument to assess postoperative bowel function in a population with low educational and socioeconomic levels.

3.
Science ; 378(6617): 317-322, 2022 10 21.
Article in English | MEDLINE | ID: mdl-36264797

ABSTRACT

In the mitochondrial outer membrane, α-helical transmembrane proteins play critical roles in cytoplasmic-mitochondrial communication. Using genome-wide CRISPR screens, we identified mitochondrial carrier homolog 2 (MTCH2), and its paralog MTCH1, and showed that it is required for insertion of biophysically diverse tail-anchored (TA), signal-anchored, and multipass proteins, but not outer membrane ß-barrel proteins. Purified MTCH2 was sufficient to mediate insertion into reconstituted proteoliposomes. Functional and mutational studies suggested that MTCH2 has evolved from a solute carrier transporter. MTCH2 uses membrane-embedded hydrophilic residues to function as a gatekeeper for the outer membrane, controlling mislocalization of TAs into the endoplasmic reticulum and modulating the sensitivity of leukemia cells to apoptosis. Our identification of MTCH2 as an insertase provides a mechanistic explanation for the diverse phenotypes and disease states associated with MTCH2 dysfunction.


Subject(s)
Apoptosis , Mitochondrial Membrane Transport Proteins , Mitochondrial Membranes , Mitochondrial Membrane Transport Proteins/chemistry , Mitochondrial Membrane Transport Proteins/genetics , Mitochondrial Membranes/metabolism , Humans , Endoplasmic Reticulum/metabolism , K562 Cells
4.
PLoS Negl Trop Dis ; 16(3): e0010167, 2022 03.
Article in English | MEDLINE | ID: mdl-35255093

ABSTRACT

Although multiple antigenically distinct ebolavirus species can cause human disease, previous serosurveys focused on only Zaire ebolavirus (EBOV). Thus, the extent of reactivity or exposure to other ebolaviruses, and which sociodemographic factors are linked to this seroreactivity, are unclear. We conducted a serosurvey of 539 healthcare workers (HCW) in Mbandaka, Democratic Republic of the Congo, using ELISA-based analysis of serum IgG against EBOV, Sudan ebolavirus (SUDV) and Bundibugyo ebolavirus (BDBV) glycoproteins (GP). We compared seroreactivity to risk factors for viral exposure using univariate and multivariable logistic regression. Seroreactivity against different GPs ranged from 2.2-4.6%. Samples from six individuals reacted to all three species of ebolavirus and 27 samples showed a species-specific IgG response. We find that community health volunteers are more likely to be seroreactive against each antigen than nurses, and in general, that HCWs with indirect patient contact have higher anti-EBOV GP IgG levels than those with direct contact. Seroreactivity against ebolavirus GP may be associated with positions that offer less occupational training and access to PPE. Those individuals with broadly reactive responses may have had multiple ebolavirus exposures or developed cross-reactive antibodies. In contrast, those individuals with species-specific BDBV or SUDV GP seroreactivity may have been exposed to an ebolavirus not previously known to circulate in the region.


Subject(s)
Ebolavirus , Hemorrhagic Fever, Ebola , Antibodies, Viral , Democratic Republic of the Congo/epidemiology , Glycoproteins , Health Personnel , Humans , Immunoglobulin G
5.
Cell ; 185(6): 995-1007.e18, 2022 03 17.
Article in English | MEDLINE | ID: mdl-35303429

ABSTRACT

Several ebolaviruses cause outbreaks of severe disease. Vaccines and monoclonal antibody cocktails are available to treat Ebola virus (EBOV) infections, but not Sudan virus (SUDV) or other ebolaviruses. Current cocktails contain antibodies that cross-react with the secreted soluble glycoprotein (sGP) that absorbs virus-neutralizing antibodies. By sorting memory B cells from EBOV infection survivors, we isolated two broadly reactive anti-GP monoclonal antibodies, 1C3 and 1C11, that potently neutralize, protect rodents from disease, and lack sGP cross-reactivity. Both antibodies recognize quaternary epitopes in trimeric ebolavirus GP. 1C11 bridges adjacent protomers via the fusion loop. 1C3 has a tripartite epitope in the center of the trimer apex. One 1C3 antigen-binding fragment anchors simultaneously to the three receptor-binding sites in the GP trimer, and separate 1C3 paratope regions interact differently with identical residues on the three protomers. A cocktail of both antibodies completely protected nonhuman primates from EBOV and SUDV infections, indicating their potential clinical value.


Subject(s)
Antibodies, Neutralizing , Antibodies, Viral , Ebolavirus , Hemorrhagic Fever, Ebola , Animals , Epitopes , Glycoproteins/chemistry , Protein Subunits
6.
Dis Colon Rectum ; 65(3): 413-420, 2022 03 01.
Article in English | MEDLINE | ID: mdl-33872283

ABSTRACT

BACKGROUND: Low anterior resection syndrome has a negative impact on quality of life. Intestinal irrigation is a method of lavage consisting of a scheduled evacuation. OBJECTIVE: This study aims to evaluate functional and quality-of-life outcomes in patients with low anterior resection syndrome after transanal irrigation using a colostomy irrigation system. DESIGN: This was a prospective case series. SETTINGS: This study presents a single-center experience at a tertiary oncological center in an upper-middle-income country. PATIENTS: Patients classified as having minor or major low anterior resection syndrome 12 months after their operation were selected. INTERVENTIONS: Transanal irrigation was performed using an ostomy irrigation kit. Questionnaires assessing patients' bowel function (low anterior resection syndrome and Wexner score) and quality of life (Short Form-36 questionnaire) were applied before and after treatment. MAIN OUTCOME MEASURES: The primary outcomes were low anterior resection syndrome score and quality-of-life improvement after a 12-month treatment. RESULTS: Of the 22 patients included, 20 had major and 2 had minor low anterior resection syndrome, with a median score of 39, especially high rates of incontinence for liquid stool (21; 95.5%), clustering (21; 95.5%), and urgency (17; 77.3%). All patients successfully completed the 3-day training, and there were no complications during the treatment. After the 12-month period, the median score was 8, with 90% of the patients classified as having "no syndrome" and great improvement in all domains of this score. The most improved quality-of-life sections were patient vitality (p = 0.025) and physical (p = 0.002), social (p = 0.001), and emotional aspects (p = 0.001). LIMITATIONS: The study was limited by its small sample size and the limited follow-up period. CONCLUSIONS: This study presents a safe implementation protocol of an ostomy irrigation device for transanal irrigation. It also adds to the literature that transanal irrigation is a safe, effective, and easily implemented procedure for patients with low anterior resection syndrome with a significant improvement in quality of life. See Video Abstract at http://links.lww.com/DCR/B563.ESTUDIO DE FACTIBILIDAD DE LA IRRIGACIÓN TRANSANAL UTILIZANDO EL SISTEMA DE IRRIGACIÓN PARA COLOSTOMÍA EN PACIENTES CON SÍNDROME DE RESECCIÓN ANTERIOR BAJAANTECEDENTES:El síndrome de resección anterior baja tiene un impacto negativo en la calidad de vida de los pacientes. La irrigación intestinal es un método de lavado que consiste en evacuaciones programadas.OBJETIVOS:Evaluar los resultados de la funcionalidad e impacto en la calidad de vida de los pacientes con síndrome de resección anterior y baja posterior a la irrigación transanal utilizando un sistema de irrigación de colostomía.DISEÑO:Es estudio prospectivo de una serie de casos.ESCENARIO:En este estudio se muestra la experiencia de un centro oncológico de tercer nivel en un país en vías de desarrollo.PACIENTES:Aquellos clasificados como síndrome con afección en menor o mayor grado doce meses después de la cirugía.METODO:Se efectuó irrigación transanal utilizando un equipo de irrigación de estomas. Se aplicaron cuestionarios para valorar la función intestinal de los pacientes (síndrome de resección anterior baja y la escala de Wexner) y para calidad de vida (Cuestionario Corto-36) antes y después del tratamiento.EVALUACION DE LOS RESULTADOS PRINCIPALES:Los principales resultados se obtuvieron de la escala del síndrome de resección baja y la mejoría en la calidad vida doce meses después de tratamiento.RESULTADOS:De los veintidós pacientes incluidos, veinte presentaron manifestaciones mayores del síndrome de resección baja y dos, manifestaciones menores. Con una media de treinta y nueve, se encontraron, especialmente, altos índices de incontinencia a líquidos (21; 95'5%) hiperdefecación "clustering" (21; 95'5%) y urgencia (17; 77'3%). Todos los pacientes completaron en forma satisfactoria el entrenamiento de tres días sin presentarse complicaciones durante el tratamiento. Al término del mes doce la media fue de ocho, con el 90% de los pacientes clasificados como "sin síndrome" y se observó una mejoría substancial en todos los puntos de la evaluación. Las secciones de calidad de vida que mostraron una mejoría significativa fueron: la vitalidad del paciente (p = 0'025), física (p = 0'002), social (p = 0'001) y emocional (p = 0'001).LIMITACIONES:El tamaño de la muestra es pequeño y el tiempo de seguimiento corto.CONCLUSIONES:Este estudio muestra la implementación de un protocolo seguro para la irrigación de estomas mediante un dispositivo transanal. Además contribuye con el concepto en la literatura de que la seguridad de la irrigación transanal es seguro, efectivo y facilmente reproducible para pacientes con síndrome de resección anterior baja con una mejoría significativa en la calidad de vida. Consulte Video Resumen en http://links.lww.com/DCR/B563. (Traducción-Dr. Miguel Esquivel-Herrera).


Subject(s)
Catheters , Intestine, Large/physiopathology , Postoperative Complications , Proctectomy/adverse effects , Quality of Life , Rectal Diseases , Rectal Neoplasms/surgery , Therapeutic Irrigation , Anastomosis, Surgical/adverse effects , Anastomosis, Surgical/methods , Equipment Design , Female , Humans , Male , Middle Aged , Neoadjuvant Therapy/methods , Neoadjuvant Therapy/statistics & numerical data , Postoperative Complications/etiology , Postoperative Complications/physiopathology , Postoperative Complications/psychology , Postoperative Complications/therapy , Proctectomy/methods , Rectal Diseases/etiology , Rectal Diseases/physiopathology , Rectal Diseases/psychology , Rectal Diseases/therapy , Rectal Neoplasms/drug therapy , Rectal Neoplasms/radiotherapy , Retrospective Studies , Therapeutic Irrigation/instrumentation , Therapeutic Irrigation/methods , Treatment Outcome
8.
Bioengineering (Basel) ; 5(1)2018 Feb 16.
Article in English | MEDLINE | ID: mdl-29462904

ABSTRACT

Lactic acid is the monomer unit of the bioplastic poly-lactic acid (PLA). One candidate organism for lactic acid production is Pichia pastoris, a yeast widely used for heterologous protein production. Nevertheless, this yeast has a poor fermentative capability that can be modulated by controlling oxygen levels. In a previous study, lactate dehydrogenase (LDH) activity was introduced into P. pastoris, enabling this yeast to produce lactic acid. The present study aimed to increase the flow of pyruvate towards the production of lactic acid in P. pastoris. To this end, a strain designated GLp was constructed by inserting the bovine lactic acid dehydrogenase gene (LDHb) concomitantly with the interruption of the gene encoding pyruvate decarboxylase (PDC). Aerobic fermentation, followed by micro-aerophilic culture two-phase fermentations, showed that the GLp strain achieved a lactic acid yield of 0.65 g/g. The distribution of fermentation products demonstrated that the acetate titer was reduced by 20% in the GLp strain with a concomitant increase in arabitol production: arabitol increased from 0.025 g/g to 0.174 g/g when compared to the GS115 strain. Taken together, the results show a significant potential for P. pastoris in producing lactic acid. Moreover, for the first time, physiological data regarding co-product formation have indicated the redox balance limitations of this yeast.

9.
J Biotechnol ; 234: 83-89, 2016 Sep 20.
Article in English | MEDLINE | ID: mdl-27485812

ABSTRACT

An important aspect related to infectious pathogens is their exceptional adaptability in developing resistance, which leads to a perpetual challenge in the discovery of antimicrobial drugs with novel mechanisms of action. Among them, antimicrobial peptides (AMPs) stand out as promising anti-infective molecules. In order to overcome the high costs associated with isolation from natural sources or chemical synthesis of AMPs we propose the expression of Pa-MAP 2, a polyalanine AMP. Pa-MAP 2 was fused to an ELP-intein tag where the ELP (Elastin-like polypeptide) was used to promote aggregation and fast and cost-effective isolation after expression, and the intein was used to stimulate a controlled AMP release. For these, the vector pET21a was used to produce Pa-MAP 2 fused to the N-termini region of a modified Mxe GyrA intein followed by 60 repetitions of ELP. Purified Pa-MAP 2 showed a MIC of 25µM against E. coli ATCC 8739. Batch fermentation demonstrated that Pa-MAP-2 can be produced in both rich and defined media at yields 50-fold higher than reported for other AMPs produced by the ELP-intein system, and in comparable yields to expression systems with protease or chemical cleavage.


Subject(s)
Anti-Bacterial Agents/biosynthesis , Elastin/genetics , Inteins , Peptide Biosynthesis , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/economics , Anti-Bacterial Agents/isolation & purification , Escherichia coli/genetics , Escherichia coli/metabolism , Fermentation , Genome, Bacterial , Peptides/chemistry , Peptides/economics , Peptides/genetics , Peptides/isolation & purification , Recombinant Fusion Proteins/biosynthesis
10.
J Intellect Disabil Res ; 60(2): 149-55, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26018613

ABSTRACT

BACKGROUND: We report striking and unanticipated improvements in maladaptive behaviours in Prader-Willi syndrome (PWS) during a trial of vagus nerve stimulation (VNS) initially designed to investigate effects on the overeating behaviour. PWS is a genetically determined neurodevelopmental disorder associated with mild-moderate intellectual disability (ID) and social and behavioural difficulties, alongside a characteristic and severe hyperphagia. METHODS: Three individuals with PWS underwent surgery to implant the VNS device. VNS was switched on 3 months post-implantation, with an initial 0.25 mA output current incrementally increased to a maximum of 1.5 mA as tolerated by each individual. Participants were followed up monthly. RESULTS: Vagal nerve stimulation in these individuals with PWS, within the stimulation parameters used here, was safe and acceptable. However, changes in eating behaviour were equivocal. Intriguingly, unanticipated, although consistent, beneficial effects were reported by two participants and their carers in maladaptive behaviour, temperament and social functioning. These improvements and associated effects on food-seeking behaviour, but not weight, indicate that VNS may have potential as a novel treatment for such behaviours. CONCLUSIONS: We propose that these changes are mediated through afferent and efferent vagal projections and their effects on specific neural networks and functioning of the autonomic nervous system and provide new insights into the mechanisms that underpin what are serious and common problems affecting people with IDs more generally.


Subject(s)
Aggression/physiology , Feeding and Eating Disorders/therapy , Prader-Willi Syndrome/therapy , Social Behavior Disorders/therapy , Vagus Nerve Stimulation/methods , Adult , Body Composition , Body Weight , Feeding and Eating Disorders/etiology , Female , Humans , Male , Prader-Willi Syndrome/complications , Social Behavior Disorders/etiology , Treatment Outcome , Vagus Nerve Stimulation/adverse effects , Young Adult
11.
J Intellect Disabil Res ; 59(9): 835-44, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25824969

ABSTRACT

BACKGROUND: This study aims to use 30-day readmission rates to investigate the presumption that men and women with learning disabilities (LDs, known internationally as intellectual disabilities) receive poorer quality hospital care than their non-disabled peers. METHOD: A 12-month retrospective audit was conducted using Hospital Episode Statistics (HES) at a single acute hospital in the East of England. This identified all in-patient admissions; admissions where the person concerned was recognised as having a LD; and all emergency readmissions within 30 days of discharge. Additionally, the healthcare records of all patients identified as having a LD and readmitted within 30 days as a medical emergency were examined in order to determine whether or not these readmissions were potentially preventable. RESULTS: Over the study period, a total of 66 870 adults were admitted as in-patients, among whom 7408 were readmitted as medical emergencies within 30 days of discharge: a readmission rate of 11%. Of these 66 870 patients, 256 were identified as having a LD, with 32 of them experiencing at least one emergency readmission within 30 days: a readmission rate of 13%. When examined, the healthcare records pertaining to these 32 patients who had a total of 39 unique 30-day readmissions revealed that 69% (n = 26) of these readmissions were potentially preventable. CONCLUSION: Although overall readmission rates were similar for patients with LDs and those from the general population, patients with LDs had a much higher rate of potentially preventable readmissions when compared to a general population estimate from van Walraven et al. This suggests that there is still work to be done to ensure that this patient population receives hospital care that is both safe and of high quality.


Subject(s)
Hospitalization/statistics & numerical data , Intellectual Disability , Learning Disabilities , Quality of Health Care/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Patient Readmission/statistics & numerical data , Retrospective Studies , Young Adult
12.
Biotechnol Adv ; 33(6 Pt 1): 648-65, 2015 Nov 01.
Article in English | MEDLINE | ID: mdl-25868803

ABSTRACT

Lovastatin, composed of secondary metabolites produced by filamentous fungi, is the most frequently used drug for hypercholesterolemia treatment due to the fact that lovastatin is a competitive inhibitor of HMG-CoA reductase. Moreover, recent studies have shown several important applications for lovastatin including antimicrobial agents and treatments for cancers and bone diseases. Studies regarding the lovastatin biosynthetic pathway have also demonstrated that lovastatin is synthesized from two-chain reactions using acetate and malonyl-CoA as a substrate. It is also known that there are two key enzymes involved in the biosynthetic pathway called polyketide synthases (PKS). Those are characterized as multifunctional enzymes and are encoded by specific genes organized in clusters on the fungal genome. Since it is a secondary metabolite, cultivation process optimization for lovastatin biosynthesis has included nitrogen limitation and non-fermentable carbon sources such as lactose and glycerol. Additionally, the influences of temperature, pH, agitation/aeration, and particle and inoculum size on lovastatin production have been also described. Although many reviews have been published covering different aspects of lovastatin production, this review brings, for the first time, complete information about the genetic basis for lovastatin production, detection and quantification, strain screening and cultivation process optimization. Moreover, this review covers all the information available from patent databases covering each protected aspect during lovastatin bio-production.


Subject(s)
Aspergillus , Hydroxymethylglutaryl-CoA Reductase Inhibitors , Lovastatin , Metabolic Engineering , Aspergillus/chemistry , Aspergillus/metabolism , Fermentation , Hydroxymethylglutaryl-CoA Reductase Inhibitors/chemistry , Hydroxymethylglutaryl-CoA Reductase Inhibitors/isolation & purification , Hydroxymethylglutaryl-CoA Reductase Inhibitors/metabolism , Lovastatin/chemistry , Lovastatin/isolation & purification , Lovastatin/metabolism
13.
Front Microbiol ; 4: 321, 2013.
Article in English | MEDLINE | ID: mdl-24198814

ABSTRACT

Cationic antimicrobial peptides (AMPs) and host defense peptides (HDPs) show vast potential as peptide-based drugs. Great effort has been made in order to exploit their mechanisms of action, aiming to identify their targets as well as to enhance their activity and bioavailability. In this review, we will focus on both naturally occurring and designed antiviral and antitumor cationic peptides, including those here called promiscuous, in which multiple targets are associated with a single peptide structure. Emphasis will be given to their biochemical features, selectivity against extra targets, and molecular mechanisms. Peptides which possess antitumor activity against different cancer cell lines will be discussed, as well as peptides which inhibit virus replication, focusing on their applications for human health, animal health and agriculture, and their potential as new therapeutic drugs. Moreover, the current scenario for production and the use of nanotechnology as delivery tool for both classes of cationic peptides, as well as the perspectives on improving them is considered.

14.
Protein Expr Purif ; 89(1): 92-6, 2013 May.
Article in English | MEDLINE | ID: mdl-23473827

ABSTRACT

The key components of the major secretion pathway in bacteria, the Sec pathway, are the proteins SecA, an ATPase that generates the energy required for protein translocation, and the heterotrimeric protein complex SecYEG, which functions as the preprotein-conducting channel through the cytoplasmic membrane, named translocon. Overexpression of exoproteins can cause jamming of the membrane, e.g., due to a shortage of translocons. Therefore, we decided to increase the number of translocons by first creating an artificial secYEG operon and then fusing it to an inducible promoter. By Western- and Northern-blot analysis, we could first show that the amount of the SecY protein and the secYEG transcript can be increased after addition of the inducer. Next, we proved by immunoblot experiments that the amount of α-amylase secreted in the presence of increased amounts of SecYEG proteins is enhanced. Therefore, increasing the number of translocons is accompanied by a concomitant increase in the amount exoenzymes. This finding will be of importance for high-level secretion of recombinant proteins.


Subject(s)
Escherichia coli Proteins/genetics , Escherichia coli/enzymology , alpha-Amylases/genetics , Adenosine Triphosphatases/chemistry , Adenosine Triphosphatases/metabolism , Escherichia coli Proteins/chemistry , Operon/genetics , SEC Translocation Channels , alpha-Amylases/biosynthesis , alpha-Amylases/metabolism
15.
Front Microbiol ; 2: 232, 2011.
Article in English | MEDLINE | ID: mdl-22125552

ABSTRACT

In the last few years, the number of bacteria with enhanced resistance to conventional antibiotics has dramatically increased. Most of such bacteria belong to regular microbial flora, becoming a real challenge, especially for immune-depressed patients. Since the treatment is sometimes extremely expensive, and in some circumstances completely inefficient for the most severe cases, researchers are still determined to discover novel compounds. Among them, host-defense peptides (HDPs) have been found as the first natural barrier against microorganisms in nearly all living groups. This molecular class has been gaining attention every day for multiple reasons. For decades, it was believed that these defense peptides had been involved only with the permeation of the lipid bilayer in pathogen membranes, their main target. Currently, it is known that these peptides can bind to numerous targets, as well as lipids including proteins and carbohydrates, from the surface to deep within the cell. Moreover, by using in vivo models, it was shown that HDPs could act both in pathogens and cognate hosts, improving immunological functions as well as acting through multiple pathways to control infections. This review focuses on structural and functional properties of HDP peptides and the additional strategies used to select them. Furthermore, strategies to avoid problems in large-scale manufacture by using molecular and biochemical techniques will also be explored. In summary, this review intends to construct a bridge between academic research and pharmaceutical industry, providing novel insights into the utilization of HDPs against resistant bacterial strains that cause infections in humans.

16.
Skin Pharmacol Physiol ; 23(5): 273-82, 2010.
Article in English | MEDLINE | ID: mdl-20484969

ABSTRACT

This study investigated the effect of emulsifiers and their liquid crystalline structures on the dermal and transdermal delivery of hydroquinone (HQ), salicylic acid (SA) and octadecenedioic acid (DIOIC). Emulsions containing liquid crystalline phases were compared with an emulsion without liquid crystals. Skin permeation experiments were performed using Franz-type diffusion cells and human abdominal skin dermatomed to a thickness of 400 mum. The results indicate that emulsifiers arranging in liquid crystalline structures in the water phase of the emulsion enhanced the skin penetration of the active ingredients with the exception of SA. SA showed a different pattern of percutaneous absorption, and no difference in dermal and transdermal delivery was observed between the emulsions with and without liquid crystalline phases. The increase in skin penetration of HQ and DIOIC could be attributed to an increased partitioning of the actives into the skin. It was hypothesized that the interaction between the different emulsifiers and active ingredients in the formulations varied and, therefore, the solubilization capacities of the various emulsifiers and their association structures.


Subject(s)
Dicarboxylic Acids/pharmacokinetics , Excipients/chemistry , Hydroquinones/pharmacokinetics , Salicylic Acid/pharmacokinetics , Administration, Cutaneous , Crystallization , Dicarboxylic Acids/administration & dosage , Emulsions , Female , Humans , Hydroquinones/administration & dosage , In Vitro Techniques , Permeability , Salicylic Acid/administration & dosage , Skin Absorption , Solubility
17.
Skin Pharmacol Physiol ; 21(6): 326-34, 2008.
Article in English | MEDLINE | ID: mdl-18832865

ABSTRACT

In this study the effect of 2 penetration modifiers, dimethyl isosorbide (DMI) and diethylene glycol monoethyl ether (DGME) on the skin delivery of hydroquinone (HQ), salicylic acid (SA) and octadecenedioic acid (DIOIC) was investigated. Ten percent DMI and DGME were separately formulated into oil-in-water emulsions containing 1.8% HQ, SA and DIOIC, respectively. Skin delivery and the flux across split-thickness human skin of the active ingredients were determined using Franz diffusion cells. An emulsion with 10% water incorporated instead of the water-soluble penetration modifiers served as a control. The study showed that neither 10% DMI nor 10% DGME significantly enhanced the skin permeation of the various lipophilic active ingredients or the uptake into the skin. It was hypothesized that the addition of the penetration modifiers to the emulsions not only enhanced the solubility of the various active ingredients in the skin but also in the formulation, resulting in a reduced thermodynamic activity and hence a weaker driving force for penetration. Therefore, the effect of DMI and DGME on the solubility of the active ingredients in the skin was counteracted by a simultaneous reduction in the thermodynamic activity in the formulation.


Subject(s)
Dicarboxylic Acids/pharmacokinetics , Excipients/chemistry , Hydroquinones/pharmacokinetics , Salicylic Acid/pharmacokinetics , Dicarboxylic Acids/administration & dosage , Diffusion , Emulsions/chemistry , Ethylene Glycols/chemistry , Female , Humans , Hydroquinones/administration & dosage , In Vitro Techniques , Isosorbide/analogs & derivatives , Isosorbide/chemistry , Salicylic Acid/administration & dosage , Skin Absorption , Solubility , Thermodynamics
18.
Insect Mol Biol ; 13(6): 625-35, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15606811

ABSTRACT

Arthropod-borne alphaviruses transmitted by mosquitoes almost exclusively use culicines; however, the alphavirus o'nyong-nyong (ONNV) has the unusual characteristic of being transmitted primarily by anopheline mosquitoes. This unusual attribute makes ONNV a valuable tool in the characterization of mosquito determinants of infection as well as a useful expression system in Anopheles species. We developed a series of recombinant alphaviruses, based upon the genome of ONNV, designed for the expression of heterologous genes. The backbone genome is a full-length infectious cDNA clone of ONNV from which wild-type virus can be rescued. Additional constructs are variants of the primary clone and contain the complete genome plus a duplicated subgenomic promoter element with a multiple cloning site for insertion of heterologous genes. We inserted a green fluorescent protein (GFP) gene downstream of this promoter and used it to characterize infection and dissemination patterns of ONNV within An. gambiae mosquitoes. These experiments allowed us to identify atypical sites of initial infection and dissemination patterns in this mosquito species not frequently observed in comparable culicine infections. The utility of these ONNVs for studies in anopheline mosquitoes includes the potential for identification of vector infection determinants and to serve as tools for antimalaria studies. Viruses that can express a heterologous gene in a vector and rapidly and efficiently infect numerous tissues in An. gambiae mosquitoes will be a valuable asset in parasite-mosquito interaction and interference research.


Subject(s)
Alphavirus/genetics , Anopheles/virology , Genetic Vectors/genetics , Animals , Cells, Cultured , DNA, Complementary/genetics , Gene Transfer Techniques , Green Fluorescent Proteins/metabolism , Reverse Transcriptase Polymerase Chain Reaction
19.
Int J Cosmet Sci ; 26(4): 173-82, 2004 Aug.
Article in English | MEDLINE | ID: mdl-18494924

ABSTRACT

Active ingredients have been around in cosmetics for a long time but have they really resulted in active cosmetic products? In order to achieve this, the right active needs to be delivered to the right location at the right concentration for the correct period of time. And the extent (and therefore the concentration) of this delivery depends on the formulation. From a rather theoretical approach based on the polarity of the active ingredient, the stratum corneum and the oil phase, the Relative Polarity Index was established that enables the selection of a suitable emollient for ensuring skin penetration of the active ingredient. Practical examples subsequently show the validity of this approach that demonstrates that one can regulate the delivery of an active molecule (and therefore the efficacy of a cosmetic formulation) by selection and control of the emollient system. Cosmetic formulations are generally quite complex mixtures and subsequent experiments using different emulsifier systems indicated that this component of a cosmetic formulation could also have an impact on steering the active ingredient to the right layer of the skin, although it is too early to be able to derive general rules from this.

20.
J Voice ; 13(3): 389-402, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10498055

ABSTRACT

Inspiratory phonation (IP) is the production of voice as air is taken into the lungs. Although IP is promoted as a laryngeal assessment and voice treatment technique, it has been described quantitatively in very few speakers. This study quantified changes in laryngeal adduction, fundamental frequency, and intensity during IP relative to expiratory phonation (EP). We hypothesized that IP would increase laryngeal abduction and fundamental frequency. The experiment was a within-subjects, repeated measures design with each subject serving as her own control. Participants were 10 females (ages 19-50 years) who underwent simultaneous transoral videostrobolaryngoscopy and acoustic voice recording. We found that membranous vocal fold contact decreased significantly during IP relative to EP, while the trends for change of ventricular fold squeeze during IP varied across individuals. Vocal fundamental frequency increased significantly during IP relative to EP, but intensity did not vary consistently across conditions. Without teaching or coaching, changes that occurred during IP did not carry over to EP produced immediately following IP within the same respiratory cycle.


Subject(s)
Laryngoscopy/methods , Phonation/physiology , Speech Acoustics , Adult , Female , Humans , Image Interpretation, Computer-Assisted , Inspiratory Capacity/physiology , Larynx/physiology , Middle Aged , Phonetics , Video Recording , Voice/physiology , Voice Quality
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