RESUMO
BACKGROUND: Despite its utility, uncertainty exists on the feasibility of acute peritoneal dialysis (PD) and optimal PD catheter type for very low birth weight (VLBW < 1500 g) and extremely low birth weight (ELBW < 1000 g) infants. We hereby report our experience of acute PD among these high-risk infants and compare the outcome between stylet-based rigid catheter (SRC) and Cook Mac-Loc Multipurpose Drainage catheters® (CMMDC). METHODS: Case notes of infants < 1500 g undergoing PD between 2012 and 2021 in a network of five participating neonatal units supported by a tertiary paediatric nephrology centre in Kolkata, India, were retrospectively reviewed. PD was conducted either with SRC or after 2018 with CMMDC. Outcome parameters included complications, survival during PD, and survival to discharge. RESULTS: 24 infants (VLBW: n = 13 and ELBW: n = 11) underwent PD at median age 4.5 days (IQR 3-6) with either CMMDC (n = 14) or SRC (n = 10). Significant improvement in biochemical parameters and fluid removal was seen in both ELBW and VLBW infants. CMMDC was associated with significantly fewer PD-related complications 7/14 (50%) vs. 9/10 (90%) (p = 0.04) and higher survival during PD 13/14 (93%) vs. 5/10 (50%) (p = 0.02), without significant difference in survival to hospital discharge 8/14 (57%) vs. 3/10 (30%) (p = 0.25). CMMDC also enabled longer duration of PD, higher ultrafiltration, and better control of acidosis. Consumable cost was higher for CMMDC (USD$60) than SRC (USD$14). CONCLUSIONS: In a low resource setting, CMMDC had lower PD complications and superior short-term survival among ELBW/VLBW infants. A higher resolution version of the Graphical abstract is available as Supplementary information.
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Diálise Peritoneal , Recém-Nascido , Criança , Lactente , Humanos , Estudos Retrospectivos , Diálise Peritoneal/efeitos adversos , Recém-Nascido de Peso Extremamente Baixo ao Nascer , Cateteres de Demora/efeitos adversos , Drenagem/efeitos adversosRESUMO
Recalcitrant dermatophytic infections of the glabrous skin (tinea corporis/cruris/faciei) pose a huge challenge to health care systems. Combinations of oral and topical drugs may potentially improve cure rates, but the same has never been objectively assessed for this condition in laboratory or clinical studies. The present study was undertaken with the aim of identifying synergistic combinations of oral and topical antifungals by testing clinical isolates obtained from patients with recalcitrant tinea corporis/cruris. Forty-two patients with tinea corporis/cruris who had failed oral antifungals or had relapsed within 4 weeks of apparent clinical cure were recruited. Twenty-one isolates were identified by sequencing (all belonging to the Trichophyton mentagrophytes/T. interdigitale species complex) and subjected to antifungal susceptibility testing (AFST) and squalene epoxidase (SQLE) gene mutation analysis. Finally, five isolates, four with underlying SQLE gene mutations and one wild-type strain, were chosen for checkerboard studies using various combinations of antifungal agents. Most isolates (n = 16) showed high MICs of terbinafine (TRB) (0.5 to >16 µg/ml), with SQLE gene mutations being present in all isolates with MICs of ≥0.5 µg/ml. Synergistic interactions were noted with combinations of itraconazole with luliconazole, TRB, and ketoconazole and propylene glycol monocaprylate (PGMC) with luliconazole and with the triple combination of PGMC with luliconazole and ketoconazole. In vitro synergistic interactions provide a sound scientific basis for the possible clinical use of antifungal combinations. Hence, these synergistic combinations may be tested for clinical utility in the wake of rising resistance among dermatophytic infections of the glabrous skin.
Assuntos
Tinha , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Arthrodermataceae , Farmacorresistência Fúngica/genética , Humanos , Mutação , Propilenoglicóis , Esqualeno Mono-Oxigenase/genética , Tinha/tratamento farmacológicoRESUMO
BACKGROUND: Dandruff is a common scalp condition characterized by excessive scaling and itch. Aberrant colonization of the scalp by commensal Malassezia spp. is a major contributor in the multifactorial etiology of dandruff. Literature based understanding of Malassezia linked pathophysiology of dandruff allowed us to comprehend a strategy to potentiate the efficacy of a known antifungal agent used in dandruff therapy. The aim of this study was to determine the efficacy and skin safety of VB-001 antidandruff leave-on formulation in comparison with marketed antidandruff ZPTO shampoo in patients with moderate adherent dandruff of the scalp. METHODS: Healthy males or females aged ≥ 15 years and ≤ 65 with a clinical diagnosis of moderate adherent dandruff of the scalp were recruited for the study to monitor the effects of topical VB-001 versus those of marketed antidandruff ZPTO shampoo. RESULTS: 168 subjects were randomized to the treatment (VB-001, n = 84) and control (ZPTO shampoo, n = 84) groups. The efficacy of each product was evaluated by comparing proportion of subjects who have shown reduction in flaking by ASFS (adherent scalp flaking score) and pruritus by IGA (investigator global assessment) score. VB-001 imparted consistently better reduction in ASFS and enabled early reduction of pruritus in comparison to marketed ZPTO shampoo. CONCLUSION: VB-001, a leave-on formulation with ingredients chosen to selectively disturb the Malassezia niche on dandruff scalp by denying extra nutritional benefits to the microbe, provides unique advantages over existing best in class ZPTO shampoo therapy. It has the potential to emerge as an attractive novel treatment for moderate adherent dandruff. TRIAL REGISTRATION: CTRI Registration number: CTRI/2013/01/003283 . Registered on: 02/01/2013.
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Antifúngicos/uso terapêutico , Caspa/tratamento farmacológico , Dermatomicoses/tratamento farmacológico , Imidazóis/uso terapêutico , Malassezia , Administração Tópica , Adolescente , Adulto , Idoso , Caspa/microbiologia , Preparações para Cabelo , Humanos , Ceratolíticos/uso terapêutico , Malassezia/efeitos dos fármacos , Pessoa de Meia-Idade , Compostos Organometálicos/uso terapêutico , Piridinas/uso terapêutico , Adulto JovemRESUMO
Acne vulgaris is a multifactorial skin disease associated with the colonization of Propionibacterium acnes. Antibiotics are a mainstay of treatment for acne, yet the emergence of resistance against the currently approved antibiotics is a serious concern. In this case report, a slow responder had multiple Propionibacterium acnes isolates with varied levels of sensitivity to the conventional antibiotics. The bacterial isolates obtained from acne samples collected from the patient were analyzed for phylogeny, and was found to be largely restricted to two different lineage patterns. Propionibacterium acnes phylotype IA1, which is considered to be pathogenic, displayed clindamycin sensitivity, but phylotype IB, which is associated with commensals, exhibited high clindamycin resistance. Sensitivity analysis revealed uniform resistance to macrolides, but susceptibility to tetracycline and nadifloxacin. These results implicate Propionibacterium acnes in the pathophysiology of acne vulgaris, although the lines between commensal and pathological phylotypes may be blurred. Switching the patient to a combination of minocycline and nadifloxacin resulted in a significant improvement in the clinical lesions. Such a science-driven judicious selection of antibiotics can minimize the probability of development of resistance, and might be the way forward in the treatment of acne.
Assuntos
Acne Vulgar/tratamento farmacológico , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana , Substituição de Medicamentos , Fluoroquinolonas/uso terapêutico , Minociclina/uso terapêutico , Propionibacterium acnes/efeitos dos fármacos , Quinolizinas/uso terapêutico , Pele/efeitos dos fármacos , Acne Vulgar/diagnóstico , Acne Vulgar/microbiologia , Quimioterapia Combinada , Genótipo , Humanos , Masculino , Fenótipo , Filogenia , Propionibacterium acnes/classificação , Propionibacterium acnes/genética , Propionibacterium acnes/patogenicidade , Indução de Remissão , Ribotipagem , Pele/microbiologia , Resultado do Tratamento , Adulto JovemRESUMO
Propionibacterium acnes is a key pathogenic factor in the development of acne. Antibiotics are the first choice of treatment for mild-to-moderate, mixed, papular/pustular, and moderate nodular acne, and an alternative choice in severe, nodular/conglobate acne. The emergence of resistance to the currently available antibiotics poses a serious set-back to this algorithm, and the reduced arsenal can diminish efficacy of treatment. This emerging situation should catalyze innovations in dermatology; for example, newer drugs and technologies such as next-generation antibiotics with excellent potency and low propensity to develop resistance, rapid diagnostic platforms to select responders and nonresponders, and delivery technologies that target the bacteria. Such innovations can dramatically expand the arsenal for dermatologists in the management of acne.
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Acne Vulgar/microbiologia , Farmacorresistência Bacteriana , Propionibacterium acnes , Acne Vulgar/tratamento farmacológico , Acne Vulgar/epidemiologia , Administração Cutânea , Antibacterianos/administração & dosagem , Farmacorresistência Bacteriana Múltipla , Saúde Global , Humanos , Testes de Sensibilidade Microbiana , Prevalência , Propionibacterium acnes/efeitos dos fármacos , Estados Unidos/epidemiologiaRESUMO
JUSTIFICATION: The preconception period is the earliest window of opportunity to ensure optimal human development. Pregnancy and childbirth outcomes can be improved by interventions offered to support the health and well-being of women and couples prior to conception. Thus, preconception care is essential in preparing for the first thousand days of life. Adolescence, the stage of life that typically comes before the preconception stage, is characterized by various high-risk behaviors like substance abuse, sexual experimentation, injuries, obesity, and mental health issues which can adversely affect their health in adult life. Thus, a Consensus Guideline for pediatricians on providing preconception care to adolescents and young adults can go a long way in making the generations to come, healthier and more productive. OBJECTIVES: The purpose of these recommendations is to formulate an evidence-based Consensus Statement that can serve as a guidance for medical professionals to provide preconception care for young adults and adolescents. INTENDED USERS: All obstetric, pediatric, and adolescent health care providers. TARGET POPULATION: Adolescents and young adults. PROCESS: A large proportion of adolescents seek care from pediatricians and there is a lack of Consensus Guidelines on preconception care. Therefore, the Indian Academy of Pediatrics called an online National Consultative Meeting on April 03, 2023, under the chairmanship of Dr MKC Nair and the National Convenor Dr Himabindu Singh. A group of pediatricians with wide experience and expertise in adolescent health care were assigned the task of formulating evidence-based guidelines on preconception care. The group conducted a comprehensive review of existing evidence by searching resources including PubMed and Cochrane databases. Subsequently, a physical meeting was held at Amritsar on October 07, 2023 during which the consensus was reached through discussions and voting. The level of evidence (LoE) of each recommendation was graded as per the Oxford Centre for Evidence-Based Medicine (OCEBM) 2011. RECOMMENDATIONS: Every woman planning a pregnancy needs to attain and maintain a eumetabolic state. Prospective couples need to be counselled on the importance of a healthy lifestyle including a nutritious diet, avoidance of substance abuse, and timely screening for genetic disorders. Screening for and management of sexually transmitted diseases in males and females, appropriate vaccination and addressing mental health concerns are also recommended.
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Cuidado Pré-Concepcional , Transtornos Relacionados ao Uso de Substâncias , Adolescente , Feminino , Humanos , Masculino , Gravidez , Adulto Jovem , Povo Asiático , Consenso , Estudos ProspectivosRESUMO
INTRODUCTION: There is an epidemic emergence of increased resistance in dermatophytes with to antifungal drugs with ergosterol1 (Erg1) and Erg11 mutations to terbinafine and azoles. Apart from mutations, mechanisms that predict clinical failure include efflux pumps, cellular kinases, heat shock proteins (Hsp), and biofilms. Apart from itraconazole and SUBATM (Super-Bioavailable) itraconazole, measures that can be used in terbinafine failure include efflux-pump inhibitors, Hsp inhibitors and judicious use of antifungal drugs (topical + systemic) combinations. AREAS COVERED: A PubMed search was done for the relevant studies and reviews published in the last 22 years using keywords dermatophytes OR Trichophyton, anti-fungal, resistance, mechanism and fungal AND resistance mechanisms. Our aim was to look for literature on prevalent species and we specifically researched studies on Trichophyton genus. We have analyzed varied antifungal drug mechanisms and detailed varied experimental and approved drugs to treat recalcitrant dermatophytosis. EXPERT OPINION: Apart from administering drugs with low minimum inhibitory concentration, combinations of oral and topical antifungals (based on synergy data) and new formulations of existing drugs are useful in recalcitrant cases. There is a need for research into resistance mechanism of the existent Trichophyton strains in therapeutic failures in tinea corporis & cruris instead of data derived from laboratory strains which may not mirror clinical failures.
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Arthrodermataceae , Tinha , Humanos , Antifúngicos , Terbinafina/farmacologia , Terbinafina/uso terapêutico , Trichophyton/genética , Itraconazol/farmacologia , Itraconazol/uso terapêutico , Tinha/tratamento farmacológico , Tinha/microbiologia , Testes de Sensibilidade MicrobianaRESUMO
BACKGROUND: Recalcitrant dermatophyte infections are being reported from various parts of the world due to varied causes including strain variation, steroid misuse, SQLE mutations, and variable quality of itraconazole pellet formulations. The oral drug preferred in endemic areas is itraconazole, to which MIC levels remain low, and clinical failures to itraconazole reported defy a sound scientific explanation. OBJECTIVES: The objective of the study was to conduct a proteomic and genomic analysis on isolates from therapeutically recalcitrant case with isolation of gene mutations and enzymatic abnormalities to explain azole failures. METHODS: Trichophyton mentagrophyte interdigitale complex strains were isolated from seven clinically non-responding tinea corporis/cruris patients, who had failed a sequential course of 6 weeks of terbinafine 250 mg QD and itraconazole 100 mg BID. After AFST 1 strain, KA01 with high MIC to most drugs was characterized using whole genome sequencing, comparative proteomic profiling, and total sterol quantification. RESULTS: Sterol quantification showed that the standard strain of Trichophyton mentagrophytes (MTCC-7687) had half the ergosterol content than the resistant KA01 strain. Genomic analysis revealed mutations in SQLE, ERG4, ERG11, MDR1, MFS genes, and a novel ERG3 mutation. Proteomic analysis established the aberrant expression of acetyl Co-A transferase in the resistant strain and upregulation of thioredoxin reductase and peroxiredoxin. CONCLUSION: Our findings demonstrate possible reasons for multidrug resistance in the prevalent strain with mutations in genes that predict terbinafine (SQLE) and azole actions (ERG4, ERG11, ERG3) apart from efflux pumps (MDR1, MFS) that can explain multidrug clinical failures.
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Antifúngicos , Tinha , Humanos , Terbinafina/uso terapêutico , Antifúngicos/uso terapêutico , Antifúngicos/farmacologia , Itraconazol/uso terapêutico , Proteômica , Trichophyton/genética , Tinha/tratamento farmacológico , Tinha/epidemiologia , Mutação , Farmacorresistência Fúngica/genética , Testes de Sensibilidade Microbiana , Regulador Transcricional ERG/genéticaRESUMO
Notch3 signaling is fundamental for arterial specification of systemic vascular smooth muscle cells (VSMCs). However, the developmental role and signaling properties of the Notch3 receptor in the mouse pulmonary artery remain unknown. Here, we demonstrate that Notch3 is expressed selectively in pulmonary artery VSMCs, is activated from late fetal to early postnatal life, and is required to maintain the morphological characteristics and smooth muscle gene expression profile of the pulmonary artery after birth. Using a conditional knock-out mouse model, we show that Notch3 receptor activation in VSMCs is Jagged1-dependent. In vitro VSMC lentivirus-mediated Jagged1 knockdown, confocal localization analysis, and co-culture experiments revealed that Notch3 activation is cell-autonomous and occurs through the physical engagement of Notch3 and VSMC-derived Jagged1 in the interior of the same cell. Although the current models of mammalian Notch signaling involve a two-cell system composed of a signal-receiving cell that expresses a Notch receptor on its surface and a neighboring signal-sending cell that provides membrane-bound activating ligand, our data suggest that pulmonary artery VSMC Notch3 activation is cell-autonomous. This unique mechanism of Notch activation may play an important role in the maturation of the pulmonary artery during the transition to air breathing.
Assuntos
Pulmão/irrigação sanguínea , Pulmão/crescimento & desenvolvimento , Artéria Pulmonar/citologia , Artéria Pulmonar/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais , Animais , Biomarcadores/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Espaço Intracelular/metabolismo , Proteína Jagged-1 , Proteínas de Membrana/metabolismo , Camundongos , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Especificidade de Órgãos , Gravidez , Transporte Proteico , Ratos , Receptor Notch3 , Proteínas Serrate-Jagged , Fatores de TempoRESUMO
New antibiotics should ideally exhibit activity against drug-resistant bacteria, delay the development of bacterial resistance to them and be suitable for local delivery at desired sites of infection. Here, we report the rational design, via molecular-docking simulations, of a library of 17 candidate antibiotics against bone infection by wild-type and mutated bacterial targets. We screened this library for activity against multidrug-resistant clinical isolates and identified an antibiotic that exhibits potent activity against resistant strains and the formation of biofilms, decreases the chances of bacterial resistance and is compatible with local delivery via a bone-cement matrix. The antibiotic-loaded bone cement exhibited greater efficacy than currently used antibiotic-loaded bone cements against staphylococcal bone infections in rats. Potent and locally delivered antibiotic-eluting polymers may help address antimicrobial resistance.
Assuntos
Antibacterianos , Cimentos Ósseos , Ratos , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Biofilmes , Próteses e ImplantesRESUMO
The prevalence of drug-resistant pathogenic fungi is a major global health challenge. There is an urgent need for novel drugs that can exert a potent antifungal activity and overcome resistance. Newly discovered anti-fungal properties of existing compounds can potentially offer a rapid solution to address this persistent threat. We rationalized that structures which disrupt the fungal cell membrane could address the above unmet need. As fatty acids underpin the formation and stability of cell membranes, we used computational simulations to evaluate the interactions between selected short chain fatty acids and a model cell membrane. Here, we report that caprylic acid could penetrate and perturb the membrane in silico. Based on the in silico findings, we identified a derivative of this fatty acid that disrupts fungal membranes as detected using steady-state fluorescence anisotropy. We show that this fatty acid derivative is potent against a variety of fungal pathogens like Candida and Trichophyton. We further demonstrated the ability of this fatty acid derivative to potentiate some azoles in vitro and enhance the efficacy of antifungal formulations in vivo. Our data suggests the emergence of a novel therapy for effective disease management and overcoming anti-fungal drug resistance.
RESUMO
BACKGROUND AND OBJECTIVES: The emergence of resistant strains of Cutibacterium acnes can limit the efficacy of currently approved antibiotics for acne. VB-1953 is a next-generation antibiotic that exerts a bactericidal effect on resistant C. acnes. In this study, we investigated the safety, tolerability, and efficacy of VB-1953 topical gel in patients with moderate to severe acne having clindamycin-resistant C. acnes. METHODS: An investigator-initiated, open label, single-arm clinical study was conducted in patients with moderate to severe facial acne vulgaris showing poor or no response to previous clindamycin treatment. Nineteen subjects were enrolled in the study based on laboratory screening for the presence of clindamycin-resistant C. acnes in acne swab samples collected from patients. VB-1953 2% gel was applied on the entire face twice daily over 12 weeks. The primary efficacy endpoints were absolute changes in inflammatory and noninflammatory lesion counts from baseline at week 12, while the secondary efficacy endpoint was the proportion of subjects achieving Investigator Global Assessment success (score of 0 or 1) or a grade 2 or higher improvement from baseline at week 12. The presence and severity of local skin reactions (erythema, edema, scaling/dryness, burning/stinging, pruritus) were evaluated for safety. Additionally, the detection and quantification of drug-resistant C. acnes strains were performed in the laboratory using acne swab samples collected from patients. RESULTS: The occurrence of treatment-emergent adverse events or changes in vital signs, physical examinations, and urinalysis for any of the patients during the course of the entire study were clinically insignificant. Topical application of 2% VB-1953 topical gel resulted in a significant reduction of mean absolute inflammatory and noninflammatory lesion counts by 53.1% and 52.2%, respectively (p < 0.0001 for both), with an Investigator Global Assessment success of 26.3% at week 12 compared with baseline. Resistant bacteria were reduced by (94.3 ± 1%; p < 0.05) within 12 weeks of treatment with VB-1953. CONCLUSION: These results indicate that VB-1953 topical gel can be a safe and effective therapy for moderate to severe acne with underlying resistant C. acnes in subjects who had not responded to previous antibiotic treatments.
Assuntos
Acne Vulgar/tratamento farmacológico , Farmacorresistência Bacteriana/efeitos dos fármacos , Propionibacterium acnes/efeitos dos fármacos , Acne Vulgar/diagnóstico , Administração Tópica , Adolescente , Adulto , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Clindamicina/farmacologia , Feminino , Géis/administração & dosagem , Géis/farmacologia , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Compostos Orgânicos/administração & dosagem , Compostos Orgânicos/farmacologia , Estudos Prospectivos , Adulto JovemRESUMO
BACKGROUND: Uninhibited proliferation of Malassezia spp., enhanced sebaceous gland activity and individual sensitivity are three prime etiological factors behind dandruff. For many dandruff sufferers, existing anti-dandruff products start yielding unsatisfactory results after a few cycles of use. This observation made us explore the physical and biological environment of the host and exploit the specific type of lipid dependence of Malassezia spp. for their survival. A shampoo formulation (product code VB-3222) was developed to address the shortcomings of existing therapy. PURPOSE: Evaluating efficacy of VB-3222 in comparison to marketed products through in vitro assays and subsequently demonstrating its advantages in a clinical study. METHODS: VB-3222 was developed with a derivative of medium chain fatty acid (MCFA) and zinc pyrithione and compared against marketed comparators by in vitro time kill assay. Subsequently, VB-3222 shampoo was tested in a 21-day clinical trial on 25 moderate dandruff subjects to evaluate local safety and efficacy. RESULTS: VB-3222 in all in vitro cases demonstrated significantly better fungicidal activity than its marketed comparators. In the clinical trial, VB-3222 was well tolerated in all subjects and imparted consistent reduction of the ASFS (adherent scalp flaking score) and the pruritus score. At days 7 and 21, 55% and 90% reduction in the ASFS in comparison to treatment initiation and 50% and 95.5% reduction in the pruritus score were observed. CONCLUSION: The increased efficacy of VB-3222 over comparator products in vitro, and the dramatic reduction (>90%) in ASFS and pruritis in subjects within 21 days of use with excellent tolerability and sensorial profile, positions VB-3222 as the new generation treatment for adherent dandruff. CLINICAL TRIAL REGISTRATION NO: CTRI/2018/05/013567.
RESUMO
Acne is a multifactorial skin disease, underpinned by colonization of Propionibacterium acnes and inflammation. The emergence of resistant P. acnes strains has affected the current acne treatment algorithm. This setback served as an impetus for rationally designing a library of next-generation antibiotics that exhibit a bactericidal effect on resistant P. acnes and exert an immunomodulatory function to reduce inflammation. In silico screening showed that one of the molecules, VCD-004, exhibits improved mode of binding to bacterial DNA gyrase. VCD-004 shows high potency against clinical isolates of resistant P. acnes and excellent efficacy in vivo. Furthermore, VCD-004 exhibits a superior mutant prevention index, suggesting that it impedes the development of resistance better than clindamycin. Additionally, it shows optimal skin penetration and has a potent anti-inflammatory effect via reduction of proinflammatory cytokines (IL-6) independent of its antibacterial action. VCD-004 affects P. acnes-induced nuclear accumulation of NF-κB in THP-1 cells. The in vitro viability of human keratinocytes in the presence of VCD-004 indicates a desirable therapeutic window for topical use. Such rationally designed bactericidal and immunomodulatory dual pharmacophore-based lipophilic molecule(s) can emerge as the next-generation topical therapy for acne with underlying resistant P. acnes etiology.
Assuntos
Acne Vulgar/tratamento farmacológico , Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Desenho de Fármacos , Propionibacterium acnes/efeitos dos fármacos , Acne Vulgar/microbiologia , Administração Tópica , Animais , Antibacterianos/química , Antibacterianos/uso terapêutico , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Linhagem Celular , Simulação por Computador , DNA Girase/química , DNA Girase/metabolismo , Modelos Animais de Doenças , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Feminino , Humanos , Interleucina-6/imunologia , Interleucina-6/metabolismo , Queratinócitos/efeitos dos fármacos , Queratinócitos/imunologia , Queratinócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Simulação de Acoplamento Molecular , Estrutura Molecular , Monócitos , Permeabilidade , Propionibacterium acnes/metabolismo , Propionibacterium acnes/fisiologia , Ratos , Ratos Sprague-Dawley , Pele/efeitos dos fármacos , Pele/imunologia , Pele/metabolismo , Resultado do TratamentoRESUMO
Effect of M. tuberculosis infection was studied on the expression of intercellular adhesion molocule-1 (ICAM-1) and Mac-1 markers on murine peritoneal macrophages. Intraperitoneal administration of M. tuberculosis resulted in a marked increase in the proportion of Mac-1(+) cells whereas the proportion of ICAM-1(+) cells declined sharply 4 h post infection. Absolute numbers of Mac-1(+) and ICAM-1(+) cells however increased at all time points after the infection. Comparison of kinetics of changes observed in Mac-1(+) and ICAM-1(+) cell populations with differential leukocyte counts in peritoneal cells indicated that these alterations could be due to cellular influx, especially that of neutrophils, or up regulation of these markers on macrophages and other peritoneal cells. In adherent peritoneal macrophages infected in vitro with M. tuberculosis, proportion of Mac-1(+) and ICAM-1(+) cells increased markedly within 24 h of infection. Mean expression of these markers on per cell basis also increased significantly. Similar results were obtained by using RAW 264.7 mouse macrophage cell line, suggesting that the enhanced expression of Mac-1 and ICAM-1 markers was a direct effect of M. tuberculosis infection and not mediated by contaminating cell types present in adherent macrophage preparations. Mac-1 and ICAM-1 expression was further studied on macrophages that had actually engulfed M. tuberculosis and compared with bystander macrophages without intracellular M. tuberculosis. For this purpose M. tuberculosis pre-stained with DilC18 fluorescent dye were used for infecting adherent peritoneal macrophages. Mac-1 and ICAM-1 expression on gated DilC18 positive and negative cell populations was analyzed. Our results indicate that the expression of Mac-1 and ICAM- 1 markers was significantly enhanced on all macrophages incubated with M. tuberculosis but was more pronounced on macrophages with internalized mycobacteria. Taken together, our results suggest that the expression of Mac-1 and ICAM-1 markers is significantly up regulated as a result of exposure and infection with M. tuberculosis. Since these markers play important role in the uptake of mycobacteria as well as in the process of antigen presentation by macrophages, their upregulation may be beneficial for generation of a protective immune response to M. tuberculosis.
Assuntos
Molécula 1 de Adesão Intercelular/biossíntese , Antígeno de Macrófago 1/biossíntese , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/microbiologia , Mycobacterium tuberculosis , Tuberculose/imunologia , Animais , Biomarcadores/análise , Biomarcadores/metabolismo , Células Cultivadas , Molécula 1 de Adesão Intercelular/análise , Antígeno de Macrófago 1/análise , Camundongos , Camundongos Endogâmicos C57BL , Peritônio/microbiologia , Fagocitose/fisiologia , Regulação para CimaRESUMO
Host immunity to Mycobacterium tuberculosis is mediated by T cells that recognize and activate infected macrophages to control intracellular bacterial replication. The early appearance of T cells in the lungs of infected mice correlates with greater resistance to infection. However, it is unknown whether the trafficking of T cells to the lung following infection is dependent upon the expression of certain adhesion molecules. To address this question, we infected knockout (KO) mice that have defective expression of CD11a, CD11b, CD18, CD62, CD103, or beta7. We found that the integrins CD11a and CD18 are absolutely required for host resistance following infection with aerosolized M. tuberculosis. Although Ag-specific T cells are generated following infection of CD11a KO mice, T cell priming is delayed, T cell trafficking to the lung is impaired, and fewer ESAT6-specific CD4+ T cells are found in the lungs of CD11a KO mice compared with control mice. Thus, LFA-1 (CD11a/CD18) plays an essential role in immunity to M. tuberculosis infection.
Assuntos
Antígeno-1 Associado à Função Linfocitária/metabolismo , Tuberculose Pulmonar/imunologia , Animais , Antígeno CD11a/genética , Antígeno CD11a/metabolismo , Antígenos CD18/genética , Antígenos CD18/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Feminino , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Tuberculose Pulmonar/microbiologia , Tuberculose Pulmonar/patologiaRESUMO
Type II alveolar epithelial cells (AEC) can produce various antimicrobial and proinflammatory effector molecules. This, together with their abundance and strategic location, suggests a role in host defense against pulmonary pathogens. We report that murine type II AEC, like their human counterparts, express class II major histocompatibility complex (MHC). Using a murine model of pulmonary tuberculosis, we find that type II AEC become activated and have increased cell surface expression of class II MHC, CD54, and CD95 following infection. Type II AEC use the class II MHC pathway to process and present mycobacterial antigens to immune CD4+ T cells isolated from mice infected with Mycobacterium tuberculosis. Therefore, not only can type II AEC contribute to the pulmonary immunity by secreting chemokines that recruit inflammatory cells to the lung, but they can also serve as antigen-presenting cells. Although type II AEC are unlikely to prime naïve T cells, their ability to present antigens to T cells demonstrates that they can participate in the effector phase of the immune response. This represents a novel role for type II AEC in the immunological response to pulmonary pathogens.