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1.
Eur Arch Otorhinolaryngol ; 281(1): 509-513, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37816840

RESUMO

BACKGROUND: Mycetoma is a slowly progressive chronic granulomatous disease of the skin, subcutaneous tissue, and underlying or adjacent cartilage or bone. Most commonly involves the foot region. Other parts such as the knee, arm, leg, head, neck, thigh, perineum, chest, abdominal walls, facial bones, mandible, paranasal sinuses, eyelid, vulva, orbit, and scrotum are seldom affected. METHODS: This is a rare presentation of Eumycotic mycetoma involving the nasal septum. Surgical debridement is done under local anesthesia. Histopathological examination of debrided specimen guided in the diagnosis and treatment. RESULTS: Histopathological examination is the one that confirms the diagnosis and rules out the other granulomatous conditions and fungal rhinitis causing septal perforation. CONCLUSIONS: In an immunocompromised state, we know that mucormycosis and zygomycosis are known to cause aggressive complications like orbital invasion and palatal perforation by vascular route. However, other fungal infections also can lead to septal perforations whenever there is lessened resistance by the mucosal barrier due to trauma (nasal intubations).


Assuntos
Micetoma , Micoses , Seios Paranasais , Masculino , Feminino , Humanos , Micetoma/diagnóstico , Micetoma/microbiologia , Micetoma/patologia , Diálise Renal , Micoses/diagnóstico , Seios Paranasais/patologia , Septo Nasal/cirurgia , Septo Nasal/patologia
2.
J Oncol Pharm Pract ; 28(1): 250-254, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34162250

RESUMO

INTRODUCTION: Steven-Johnson syndrome (SJS) is a serious mucocutaneous reaction, characterized by fever, influenza-like symptoms and followed by dermatological manifestations. Capecitabine is an oral fluoropyrimidine carbamate analogue of 5-Fluorouracil (5-FU). It is widely accepted for many malignancies because of its better safety profile and tolerability. Hand-foot syndrome is the common dermatological toxicity associated with Capecitabine and SJS is the rarest manifestation.Case presentation: We report a case of Capecitabine induced SJS in a 70 years old male patient with metastatic carcinoma pancreas. He was treated with intravenous Gemcitabine and Carboplatin initially and then switched to oral therapy with Capecitabine 1000 mg twice daily. After ten days of treatment with Capecitabine, he developed vomiting, mucositis, hyperpigmentation, itching and scrotal mucosal peeling. The clinical status of the patient was suggestive of SJS, which was confirmed by dermatologic consultation. According to Naranjo, WHO-UMC, and Hartwig's scale, the reaction was found to be probable and severe. Pharmacological as well as supportive care measures were provided, but the condition progressively worsened, and the patient was deceased. CONCLUSION: Capecitabine can cause severe hypersensitivity reactions which can be dangerous and life-threatening. Health care providers must be aware of all rare adverse effects, including SJS. Clinicians and clinical pharmacists should educate and counsel the patients regarding the likely adverse effects of their chemo drugs because the early identification of toxic symptoms is crucial to reduce further complications to the patient.


Assuntos
Antineoplásicos , Neoplasias , Síndrome de Stevens-Johnson , Idoso , Antineoplásicos/uso terapêutico , Capecitabina/efeitos adversos , Fluoruracila/efeitos adversos , Humanos , Masculino , Síndrome de Stevens-Johnson/diagnóstico , Síndrome de Stevens-Johnson/etiologia
3.
J Food Sci Technol ; 53(7): 3122-3128, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27765983

RESUMO

Ridge gourd (Luffa acutangula) is consumed as a vegetable after peeling off the skin which is a domestic waste. Luffa acutangula peel (LAP) was observed to be a good source of fiber (20.6 %) and minerals (7.7 %). Amino acid analysis revealed presence of the highest content of Carnosine followed by aspartic acid and aminoadipic acid. Antioxidant activity of different extracts showed that ethyl acetate extract was more potent when compared to other solvent extractions. It exhibited a significant amount of phenolic acids like p-coumaric acid (68.64 mg/100 g of dry weight) followed by gallic acid (34.98 mg/100 g of dry weight), protocatechuic acid (30.52 mg/100 g of dry weight) in free form and ferulic acid (13.04 mg/100 g of dry weight) in bound form.

4.
Neuroradiol J ; 37(2): 229-233, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37002537

RESUMO

Following completion of adjuvant radiation and chemotherapy imaging surveillance forms a major role in the management of diffuse gliomas. The primary role of imaging is to detect recurrences earlier than clinical symptomatology. Magnetic resonance imaging (MRI) is considered the gold standard in follow-up protocols owing to better soft tissue delineation and multiparametric nature. True recurrence can often mimic treatment-related changes, it is of paramount importance to differentiate between the two entities as the clinical course is divergent. Addition of functional sequences like perfusion, spectroscopy and metabolic imaging can provide further details into the microenvironment. In equivocal cases, a follow-up short interval imaging might be obtained to settle the diagnostic dilemma. Here, we present a patient with diagnosis of recurrent oligodendroglioma treated with adjuvant chemoradiation, presenting with seizures five years post-completion of chemotherapy for recurrence. On MRI, subtle new onset gyral thickening of the left frontal region with mild increase in perfusion and patchy areas of raised choline. FET-PET (fluoro-ethyltyrosine) showed an increased tumour-to-white matter (T/Wm) ratio favouring tumour recurrence. Based on discussion in a multi-disciplinary joint clinic, short interval follow-up MRI was undertaken at two months showing decrease in gyral thickening and resolution of enhancing areas in left frontal lobe. Repeat imaging one year later demonstrated stable disease status without further new imaging findings. Given the changes resolving completely without any anti-tumoral intervention, we conclude this to be peri-ictal pseudoprogression, being the second such case described in India.


Assuntos
Neoplasias Encefálicas , Glioma , Oligodendroglioma , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patologia , Glioma/diagnóstico por imagem , Glioma/terapia , Glioma/patologia , Imageamento por Ressonância Magnética/métodos , Oligodendroglioma/diagnóstico por imagem , Oligodendroglioma/terapia , Tomografia por Emissão de Pósitrons/métodos , Microambiente Tumoral
5.
Indian J Radiol Imaging ; 34(2): 351-355, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38549893

RESUMO

Isocitrate dehydrogenase mutant gliomas generally have a better prognosis than their wild-type counterpart. Recurrences are generally within the radiation field in the primary tumoral bed. Remote recurrence is uncommon and is usually intraparenchymal. Transformation to a higher grade has been observed with TP53 mutants. Presentation of glioma as an extra-axial lesion is extremely uncommon. No such cases of remote intracranial extra-axial recurrence have been reported in the literature. We describe the unique imaging findings in this case and attempt to formulate possible diagnoses. Intraoperative and pathological findings confirmed this unusual recurrence pattern.

6.
Traffic ; 12(8): 1037-55, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21535339

RESUMO

In metazoans, lysosomes are characterized by a unique tubular morphology, acidic pH, and specific membrane protein (LAMP) and lipid (cholesterol) composition as well as a soluble protein (hydrolases) composition. Here we show that perturbation to the eye-color gene, light, results in impaired lysosomal acidification, sterol accumulation, altered endosomal morphology as well as compromised lysosomal degradation. We find that Drosophila homologue of Vps41, Light, regulates the fusion of a specific subset of biosynthetic carriers containing characteristic endolysosomal membrane proteins, LAMP1, V0-ATPase and the cholesterol transport protein, NPC1, with the endolysosomal system, and is then required for the morphological progression of the multivesicular endosome. Inhibition of Light results in accumulation of biosynthetic transport intermediates that contain these membrane cargoes, whereas under similar conditions, endosomal delivery of soluble hydrolases, previously shown to be mediated by Dor, the Drosophila homologue of Vps18, is not affected. Unlike Dor, Light is recruited to endosomes in a PI3P-sensitive fashion wherein it facilitates fusion of these biosynthetic cargoes with the endosomes. Depletion of the mammalian counterpart of Light, hVps41, in a human cell line also inhibits delivery of hLAMP to endosomes, suggesting an evolutionarily conserved pathway in metazoa.


Assuntos
Proteínas de Membrana Lisossomal/metabolismo , Lisossomos/metabolismo , Esteróis/metabolismo , Adenosina Trifosfatases/metabolismo , Animais , Proteínas de Transporte/metabolismo , Células Cultivadas , Colesterol/metabolismo , Proteínas de Ligação a DNA/metabolismo , Drosophila , Proteínas de Drosophila/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Endossomos/metabolismo , Endossomos/ultraestrutura , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Hidrolases/metabolismo , Proteína 1 de Membrana Associada ao Lisossomo/metabolismo , Lisossomos/genética , Lisossomos/ultraestrutura , Proteínas de Membrana , Proteína C1 de Niemann-Pick , Transporte Proteico/genética , Bombas de Próton/metabolismo , Células Tumorais Cultivadas , ATPases Vacuolares Próton-Translocadoras/metabolismo , Proteínas de Transporte Vesicular/metabolismo
7.
Saudi J Ophthalmol ; 37(2): 100-106, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37492213

RESUMO

PURPOSE: The purpose was to study the demographics, clinical and radiological presenting patterns, prognostic variables, and outcome of management of rhino-orbital-cerebral-mucormycosis (ROCM) in coronavirus disease (COVID-19) patients. METHODS: We retrospectively analyzed COVID-19 patients with proven ROCM from April 2021 to November 2021. All included patients were given systemic antifungal therapy depending on clinical response and underwent functional endoscopic sinus surgery (FESS) with orbital wall decompression. Administration of transcutaneous retrobulbar amphotericin B (TRAMB) injection, exenteration, and maxillectomy was done when indicated as per a novel algorithm. RESULTS: A total of 64 patients with ROCM were included in the study. The mean age of 54.5 (standard deviation [SD] - 10.6) years with a male predominance (male: female = 55:9) was observed. Pre-existing diabetes mellitus (DM) was the most common comorbid state, 47 (73.4%). The most common ophthalmic presentation was proptosis (n = 40) (62.5%). Bulky extraocular muscles (n = 64) (100%) and intraorbital fat stranding (n = 41) (64%) were the most common radiological findings. Twenty-eight patients received TRAMB, while 11 patients underwent exenteration with FESS. Our study had a mortality rate of 18.7% (n = 12). The mean glycated hemoglobin of 13.5% (SD - 1.1) and a higher serum ferritin value of 976.25 (SD - 592) were observed in the deceased group. Vision was preserved in 38 (73.7%) patients in the survived group. CONCLUSION: ROCM has a wide array of presentations, with proptosis as the most common clinical finding. Bulky EOM and intraorbital fat stranding were the most common radiological findings. Thorough surgical debridement with systemic and local antifungal therapy results in reasonable outcomes for ROCM in COVID-19 patients. Older age, intensive care unit admissions, uncontrolled DM, central nervous system involvement, and shorter duration of antifungal treatment are poor prognostic factors associated with mortality.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38044960

RESUMO

Background: The prevalence of Barrett's esophagus (BE) in African Americans (AA) is uncertain. However, several potential risk factors, includes family history, male sex, ethnicity, chronic heartburn and acid reflux, age over 60, current or past smoking, and obesity are associated with BE. The aim of this study is to determine the incidence of BE in AA patients who underwent Esophageal Gastro Endoscopy (EGD). Methods: Medical and demographic data of 1,253 AA patients with various symptoms, including BE, Esophageal adenocarcinoma (EAC), esophageal squamous adenocarcinoma (SCC), hiatal hernia, H. pylori infection, Gastro-Esophageal Reflux Disease (GERD), Gastritis, and esophagitis, were collected from January 2004 to December 2014 at Howard University Hospital. Results: Among the 1,253 patients, the median age was 61 and 49% were male out of the total. The frequencies of EAC (p= 0.05), and SCC (p= 0.002) were significantly high in males, along with SCC frequency significantly increased with older age (p<0.001). Furthermore, esophageal polyps with hiatal hernia (p=0.008) and H. pylori (p=<0.001) were found to be associated with esophagitis, and its presence may contribute to the development of BE. Conclusion: The findings highlighted the high prevalence of GERD symptoms and pathologic gastritis along with EAC was less common than SCC and both types of esophageal cancer were associated with male gender and older age whereas, H. pylori infection was identified as a risk factor for pathologic gastritis in AA. Overall data emphasize the need for extensive research, increased awareness, diagnosis, and management of GERD, gastritis, and related conditions to uncover the underlying mechanisms and factors contributing to these conditions in the AA population.

9.
J Nanosci Nanotechnol ; 12(1): 167-72, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22523961

RESUMO

The bone implants used in tissue repair are susceptible to infections caused by staphylococci, specifically Staphylococcus aureus. Hence, the development of better biological materials that provide antimicrobial activity in bone tissue engineering is required. The nanoparticles of hydroxyapatite (nHAp) and nHAp dopped with Zn (nHAp-Zn) were prepared by the wet chemical method and the ion exchange method, respectively. They were characterized using SEM, AFM, FTIR and XRD. The antibacterial activity of nHAp and nHAp-Zn was determined with Gram-negative and Gram-positive bacterial strains. The results indicated that nHAp alone was acting as an inert matrix and when substituted with Zn, it showed better antibacterial activity. The nHAp-Zn was found to be non-toxic to osteoprogenitor cells. Thus, due to the antimicrobial property of nHAp-Zn nanoparticles, we suggest that they would have potential applications towards bone tissue engineering.


Assuntos
Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Substitutos Ósseos/farmacologia , Durapatita/química , Nanoestruturas/administração & dosagem , Nanoestruturas/química , Osteoblastos/efeitos dos fármacos , Zinco/química , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Substitutos Ósseos/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Durapatita/farmacologia , Teste de Materiais , Tamanho da Partícula , Ratos , Engenharia Tecidual/métodos , Zinco/farmacologia
10.
J Contemp Dent Pract ; 12(4): 232-8, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22186856

RESUMO

AIM: The process of bonding orthodontic appliances to the enamel surface of the teeth has come to the forefront as a major improvement in bonding techniques. The purpose of this study is to compare the shear bond strength of stainless steel orthodontic brackets bonded using conventional direct bonding and indirect bonding as described by Thomas. MATERIALS AND METHODS: Forty sound human premolars were divided into two groups of 20 each. Group I samples were bonded directly on the tooth surface using concise two paste adhesive system after etching and drying. Group II samples were bonded indirectly on the tooth surface according to Thomas indirect bonding technique using concise two paste adhesive system. The stored specimen was tested for shear bond strength in an Instron universal testing machine at a crosshead speed of 0.5 mm/minute. Data obtained were subjected to statistical analysis. RESULTS: The results showed that there was no statistically significant difference in the shear bond strength between direct and indirect bonding techniques. Chi-square test showed that there were significant differences among the adhesive remnant index scores between direct and indirect bonding groups. CONCLUSION: In vitro shear bond strength comparison between direct and indirect-bonded attachments showed no significant difference between the two groups. Bond strength obtained with Thomas indirect bonding technique was comparable with direct bonding technique. CLINICAL SIGNIFICANCE: Thomas indirect bonding technique can be used for bonding of the posterior teeth, where the risk of moisture contamination is high during bonding.


Assuntos
Colagem Dentária/métodos , Braquetes Ortodônticos , Cimentos de Resina , Dente Pré-Molar , Bis-Fenol A-Glicidil Metacrilato , Distribuição de Qui-Quadrado , Ligas Dentárias , Esmalte Dentário , Análise do Estresse Dentário , Humanos , Resistência ao Cisalhamento , Aço Inoxidável , Análise de Sobrevida
11.
Indian J Ophthalmol ; 68(6): 1015-1017, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32461418

RESUMO

Purpose: To detect the presence of viral RNA of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in conjunctival swab specimens of coronavirus disease-19 (COVID-19) patients. Methods: Forty-five COVID-19 patients positive for real-time reverse transcription-polymerase chain reaction (RT-PCR) for SARS-CoV-2 in nasopharyngeal swab with or without ocular manifestations were included in the study. The conjunctival swab of each patient was collected by an ophthalmologist posted for COVID duty. Results: Out of 45 patients, 35 (77.77%) were males and the rest were females. The mean age was 31.26 ± 12.81 years. None of the patients had any ocular manifestations. One (2.23%) out of 45 patients was positive for RT-PCR SARS-CoV-2 in the conjunctival swab. Conclusion: This study shows that SARS-CoV-2 can be detected in conjunctival swabs of confirmed cases of COVID-19 patients. Though the positivity rate of detecting SARS-CoV-2 in conjunctival swabs is very less, care should be exercised during the ocular examination of patients of COVID-19.


Assuntos
Betacoronavirus/genética , Conjuntivite Viral/diagnóstico , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , RNA Viral/isolamento & purificação , Adolescente , Adulto , COVID-19 , Teste para COVID-19 , Vacinas contra COVID-19 , Criança , Técnicas de Laboratório Clínico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cavidade Nasal/virologia , Pandemias , Faringe/virologia , Estudos Prospectivos , Reação em Cadeia da Polimerase em Tempo Real , SARS-CoV-2 , Manejo de Espécimes , Adulto Jovem
12.
J Int Oral Health ; 7(7): 22-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26229366

RESUMO

BACKGROUND: Endodontically treated teeth with posts are more prone to fracture. Hence, the purpose of this study was to investigate the in-vitro fracture resistance of devitalized teeth and mode of failure restored with posts of different materials and different lengths. MATERIALS AND METHODS: Sixty freshly extracted human mandibular premolars were endodontically treated and then restored with 1 of 2 prefabricated posts: Stainless-steel (SS) and glass-fiber (fiber posts [FP]) with intraradicular lengths of 4, 5 or 10 mm (n = 10). Following core restoration, a static compressive load was applied perpendicular to the long-axis of the teeth. Initial failure of each specimen was recorded in Newton. The mode of failure was also determined radiographically. The data were analyzed using two-way ANOVA and Tukey's post-hoc analysis with Bonferroni adjustment. RESULTS: Analysis indicated significant differences (P < 0.001) among the groups. Among the SS posts, SS/7 (246 N) exhibited the highest failure load and SS/4 (122 N) the lowest. FP/10 (140.5 N) exhibited the highest failure load among the FP and FP/4 (68.5 N) the lowest. SS posts showed post pull out, followed by core fracture while FP showed core debonding, followed by core fracture as the primary mode of failure. CONCLUSION: Fracture resistance of the teeth proportionately increased with increase in the length of FP while it decreased with that of metal post. SS posts showed greater fracture resistance than FP when 90° load was applied.

13.
J Int Oral Health ; 6(2): 55-61, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24876703

RESUMO

BACKGROUND: The condition of the denture bearing tissues may be adversely affected by high stress concentration during function. Chairside Denture (Hard and Soft) reliners are used to distribute forces applied to soft tissues during function. Tensile and shear bond strength has been shown to be dependent on their chemical composition. A weak bond could harbor bacteria, promote staining and delamination of the lining material. To investigate tensile and shear bond strength of 4 different commercially available denture relining materials to conventional heat cured acrylic denture base resin. MATERIALS & METHODS: 4 mm sections in the middle of 160 Acrylic cylindrical specimens (20 mm x 8 mm) were removed, packed with test materials (Mollosil, G C Reline Soft, G C Reline Hard (Kooliner) and Ufi Gel Hard and polymerized. Specimens were divided into 8 groups of 20 each. Tensile and shear bond strength to the conventional heat cured acrylic denture base resin were examined by Instron Universal Tensile Testing Machine using the equation F=N/A (F-maximum force exerted on the specimen (Newton) and A-bonding area= 50.24 mm2). One-way ANOVA was used for multiple group comparisons followed by Bonferroni Test and Hsu's MCB for multiple pairwise comparisons to asses any significant differences between the groups. RESULTS: The highest mean Tensile bond strength value was obtained for Ufi Gel Hard (6.49+0.08 MPa) and lowest for G C Reline Soft (0.52+0.01 MPa). The highest mean Shear bond strength value was obtained for Ufi Gel Hard (16.19+0.1 MPa) and lowest for Mollosil (0.59+0.05 MPa). The Benferroni test showed a significant difference in the mean tensile bond strength and the mean shear bond strength when the two denture soft liners were compared as well as when the two denture hard liners were compared. Hsu's MCB implied that Ufi gel hard is better than its other closest competitors. CONCLUSION: The Tensile and Shear bond strength values of denture soft reliners were significantly lower than denture hard reliners. How to cite the article: Lau M, Amarnath GS, Muddugangadhar BC, Swetha MU, Das KA. Tensile and shear bond strength of hard and soft denture relining materials to the conventional heat cured acrylic denture base resin: An In-vitro study. J Int Oral Health 2014;6(2):55-61.

14.
PLoS One ; 9(6): e100554, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24971745

RESUMO

Single-cell-resolved measurements reveal heterogeneous distributions of clathrin-dependent (CD) and -independent (CLIC/GEEC: CG) endocytic activity in Drosophila cell populations. dsRNA-mediated knockdown of core versus peripheral endocytic machinery induces strong changes in the mean, or subtle changes in the shapes of these distributions, respectively. By quantifying these subtle shape changes for 27 single-cell features which report on endocytic activity and cell morphology, we organize 1072 Drosophila genes into a tree-like hierarchy. We find that tree nodes contain gene sets enriched in functional classes and protein complexes, providing a portrait of core and peripheral control of CD and CG endocytosis. For 470 genes we obtain additional features from separate assays and classify them into early- or late-acting genes of the endocytic pathways. Detailed analyses of specific genes at intermediate levels of the tree suggest that Vacuolar ATPase and lysosomal genes involved in vacuolar biogenesis play an evolutionarily conserved role in CG endocytosis.


Assuntos
Clatrina/metabolismo , Proteínas de Drosophila/metabolismo , Endocitose/fisiologia , Animais , Células CHO , Células Cultivadas , Clatrina/genética , Cricetinae , Cricetulus , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Drosophila/genética , Proteínas de Drosophila/antagonistas & inibidores , Proteínas de Drosophila/genética , Endocitose/genética , Proteínas do Olho/antagonistas & inibidores , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Perfilação da Expressão Gênica , Hemócitos/citologia , Hemócitos/metabolismo , Humanos , Proteínas Qa-SNARE/antagonistas & inibidores , Proteínas Qa-SNARE/genética , Proteínas Qa-SNARE/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , ATPases Vacuolares Próton-Translocadoras/química , ATPases Vacuolares Próton-Translocadoras/metabolismo
15.
Nat Commun ; 4: 1361, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23322049

RESUMO

Targeted delivery of lysosome-associated membrane proteins is important for lysosome stability and function. Here we identify a pathway for transport of lysosome-associated membrane proteins directly from the trans-Golgi network to late endosomes, which exists in parallel to mannose 6-phosphate receptor and clathrin-dependent transport of lysosomal enzymes to early endosomes. By immunoelectron microscopy we localized endogenous LAMP-1 and -2 as well as LAMP-1-mGFP to non-coated, biosynthetic carriers at the trans-Golgi network and near late endosomes. These LAMP carriers were negative for mannose 6-phosphate receptor, adaptor-protein complex-1, secretory albumin and endocytic markers, but contained the homotypic fusion and protein sorting complex component hVps41 and the soluble N-ethylmaleimide-sensitive factor attachment protein receptors protein VAMP7. Knockdown of hVps41 or VAMP7 resulted in the accumulation of lysosome-associated membrane protein carriers, whereas knockdown of hVps39 or hVps18 did not, indicating that the effect of hVps41 is independent of CORVET/HOPS. Mannose 6-phosphate receptor carriers remained unaffected upon hVps41 or VAMP7 knockdown, implicating that hVps41 and VAMP7 are specifically involved in the fusion of trans-Golgi network-derived lysosome-associated membrane protein carriers with late endosomes.


Assuntos
Endossomos/metabolismo , Proteínas de Membrana Lisossomal/metabolismo , Proteínas R-SNARE/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Rede trans-Golgi/metabolismo , Animais , Clatrina/metabolismo , Endossomos/ultraestrutura , Técnicas de Silenciamento de Genes , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Células Hep G2 , Humanos , Proteína 2 de Membrana Associada ao Lisossomo , Modelos Biológicos , Transporte Proteico , Ratos , Receptor IGF Tipo 2/metabolismo , Vesículas Secretórias/metabolismo , Vesículas Secretórias/ultraestrutura , Rede trans-Golgi/ultraestrutura
16.
J Biomed Nanotechnol ; 6(4): 333-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21323106

RESUMO

The bacterial infection is one of the major problems associated with implant and reconstructive surgery of bone. Hence, the aim of this study was to develop biomaterials having antibacterial activity for bone tissue engineering. The hydroxyapatite nanoparticles (nHAp) improve the mechanical properties and incorporate nanotopographic features that mimic the nanostructure of natural bone. We report here for the first time the synthesis and characterization of nHAp and nHAp soaked with copper (nHAp-Cu) using SEM, AFM, FTIR and XRD. The antibacterial activity of nHAp and nHAp-Cu was determined using Gram-positive and Gram-negative bacterial strains. To have accelerated antibacterial activity, polyethylene glycol 400 (PEG 400), a synthetic biodegradable polymer was also added along with nHAp-Cu. The nHAp-Cu/PEG 400 had increased antibacterial activity towards Gram-positive than Gram-negative bacterial strains. The cytotoxicity of nHAp-Cu/PEG 400 was determined using MTT assay with rat primary osteoprogenitor cells and these biomaterials were found to be non-toxic. Hence, based on these results we suggest that the biomaterials containing nHAp-Cu/PEG 400 can be used as antibacterial materials in bone implant and bone regenerative medicine.


Assuntos
Antibacterianos/síntese química , Materiais Biocompatíveis/síntese química , Osso e Ossos , Cobre/química , Durapatita/química , Nanopartículas , Engenharia Tecidual , Animais , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Osso e Ossos/citologia , Linhagem Celular , Nanopartículas/química , Polietilenoglicóis/química , Ratos
17.
PLoS One ; 4(8): e6768, 2009 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-19707569

RESUMO

In mammalian cells, endocytosis of the fluid phase and glycosylphosphatidylinositol-anchored proteins (GPI-APs) forms GEECs (GPI-AP enriched early endosomal compartments) via an Arf1- and Cdc42-mediated, dynamin independent mechanism. Here we use four different fluorescently labeled probes and several markers in combination with quantitative kinetic assays, RNA interference and high resolution imaging to delineate major endocytic routes in Drosophila cultured cells. We find that the hallmarks of the pinocytic GEEC pathway are conserved in Drosophila and identify garz, the fly ortholog of the GTP exchange factor GBF1, as a novel component of this pathway. Live confocal and TIRF imaging reveals that a fraction of GBF1 GFP dynamically associates with ABD RFP (a sensor for activated Arf1 present on nascent pinosomes). Correspondingly, a GTP exchange mutant of GBF1 has altered ABD RFP localization in the evanescent field and is impaired in fluid phase uptake. Furthermore, GBF1 activation is required for the GEEC pathway even in the presence of Brefeldin A, implying that, like Arf1, it has a role in endocytosis that is separable from its role in secretion.


Assuntos
Drosophila/metabolismo , Endocitose , Fatores de Ligação G-Box/metabolismo , Animais , Drosophila/citologia , Proteínas de Fluorescência Verde/genética , Interferência de RNA
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