Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Biomacromolecules ; 18(5): 1449-1459, 2017 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-28328191

RESUMEN

Tumor-targeted nanomedicines have been extensively applied to alter the drawbacks and enhance the efficacy of chemotherapeutics. Despite the large number of preclinical nanomedicine studies showing initial success, their therapeutic benefit in the clinic has been rather modest, which is partially due to the inefficient tumor penetration caused by the tumor microenvironment (high density of cells and extracellular matrix, increased interstitial fluid pressure). Furthermore, tumor penetration of nanomedicines is significantly influenced by physicochemical characteristics, such as size, surface chemistry, and shape. The effect of size on tumor penetration has been exploited to design nanomedicines with switchable size to tackle this challenge. Moreover, several pharmacological and physical approaches have been developed to enhance the tumor penetration of nanomedicines, by penetration-promoting ligands, intratumoral drug release, and modulating the tumor microenvironment and vasculature. Overall, these efforts have resulted in nanomedicines with better tumor penetration properties and with enhanced therapeutic efficacy. Future research should be directed to penetration-promoting strategies with broad applicability and with high translational potential.


Asunto(s)
Nanomedicina/métodos , Nanopartículas/metabolismo , Neoplasias/tratamiento farmacológico , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacocinética , Humanos , Microambiente Tumoral
2.
Drug Discov Today Technol ; 20: 41-48, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27986222

RESUMEN

The blood-brain barrier (BBB) limits drug delivery to the central nervous system. When combined with microbubbles, ultrasound can transiently permeate blood vessels in the brain. This approach, which can be referred to as sonoporation or sonopermeabilization, holds significant promise for shuttling large therapeutic molecules, such as antibodies, growth factors and nanomedicine formulations, across the BBB. We here describe the basic principles of BBB permeation using ultrasound and microbubbles, and we summarize several (pre-) clinical studies showing the potential of BBB opening for improving the treatment of cancer and neurodegenerative disorders.


Asunto(s)
Encéfalo/metabolismo , Sistemas de Liberación de Medicamentos , Ondas Ultrasónicas , Animales , Encéfalo/irrigación sanguínea , Humanos , Permeabilidad
3.
Indian J Otolaryngol Head Neck Surg ; 76(1): 137-140, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38440439

RESUMEN

Objective: To study the efficacy of coblation in the endoscopic surgery of sinonasal and skull base masses. Study Design: Prospective Interventional Study. Method: 100 patients with signs and symptoms of nasal obstruction were enrolled for 14 months. On the basis of diagnosis they underwent endoscopic sinus surgery using coblator and their intra-operative blood loss, operation time, post-operative pain threshold using VAS(Visual analogue scale) were enlisted. Result: 80% had Sinonasal polyp followed by Inverted papilloma in 8%, Angiofibroma in 5%, Hemangioma in 3%, Esthesioneuroblastoma in 2% and Rhinosporidiosis in 2%. The Minimum blood loss was 50 ml and Maximum was 600 ml. 30% patients had no pain, 60% had Mild pain and 10% had Moderate pain post procedure. Mean Operation time was 112.86 min. Conclusion: Coblation has proven to have reduced operation time, blood loss and faster wound healing. It has now established itself as an essential tool for advance tumours in nasal surgeries.

4.
J Mater Chem B ; 12(10): 2511-2522, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38334758

RESUMEN

Photoacoustic (PA) imaging is an emerging diagnostic technology that combines the penetration depth of ultrasound (US) imaging and the contrast resolution of optical imaging. Although PA imaging can visualize several endogenous chromophores to obtain clinically-relevant information, multiple applications require the administration of external contrast agents. Metal phthalocyanines have strong PA properties and chemical stability, but their extreme hydrophobicity requires their encapsulation in delivery systems for biomedical applications. Hence, we developed hybrid US/PA contrast agents by encapsulating metal phthalocyanines in poly(butyl cyanoacrylate) microbubbles (PBCA MB), which display acoustic response and ability to efficiently load hydrophobic drugs. Six different metal chromophores were loaded in PBCA MB, showing greater encapsulation efficiency with higher chromophore hydrophobicity. Notably, while the US response of the MB was unaffected by the loading of the chromophores, the PA characteristics varied greatly. Among the different formulations, MB loaded with zinc and cobalt naphthalocyanines showed the strongest PA contrast, as a result of high encapsulation efficiencies and tunable optical properties. The strong US and PA contrast signals of the formulations were preserved in biological environment, as demonstrated by in vitro imaging in serum and whole blood, and ex vivo imaging in deceased mice. Taken together, these findings highlight the advantages of combining highly hydrophobic PA contrast agents and polymeric MB for the development of contrast agents for hybrid US/PA imaging, where different types of information (structural, functional, or potentially molecular) can be acquired by combining both imaging modalities.


Asunto(s)
Medios de Contraste , Microburbujas , Ratones , Animales , Ultrasonografía/métodos , Polímeros/química , Imagen Multimodal
5.
Indian J Otolaryngol Head Neck Surg ; 75(3): 1469-1473, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37636795

RESUMEN

The basic principle of head and neck surgery is based on the identification and preservation of important structures, rather than avoidance. Thyroid surgeries are the most frequently performed endocrine procedures worldwide. Recurrent laryngeal nerve (RLN) palsy after thyroid surgery is a serious postoperative complication that can diminish the quality of life. While it is generally accepted that direct visualisation of the nerve is the gold standard, intraoperative nerve monitoring (IONM) is being used increasingly as an adjuvant to help identify the nerve. This study was carried out in Mahatma Gandhi medical college and hospital, Jaipur, Rajasthan from June 2018 to March 2020. 100 patients were enrolled in the study. RLN is identified & visualized in Beahr's triangle or in Lore's triangle. We have randomly selected the patient and use IONM as an adjunct to standard visual identification of the recurrent laryngeal nerve (RLN) to prevent nerve lesion. 8 out of 108 nerves which were at risk during thyroid surgery were found injured. 2 of 50 (4%) nerves at risk were injured with IONM that caused temporary paresis. Without IONM, 5 of 58 (8.6%) nerves at risk suffered temporary paresis and 1of 58(1.72%) had paralysis. Visual nerve identification alone remains the gold standard of recurrent laryngeal nerve management in thyroid surgery and one can use operating microscope for magnification. Neuromonitoring helps to identify the RLN particularly in difficult cases, but it does not decrease the injury to RLN as compared to visualization alone.

6.
Indian J Otolaryngol Head Neck Surg ; 75(2): 913-916, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37275007

RESUMEN

Synovial sarcomas are a rare entity in the head and neck region. We present a rare case of a 50 year old female presenting with a painless mass over right cheek since one year which gradually increased in size since past two months. Imaging was done which revealed a mass lesion in soft tissue of right cheek deep to the masseter muscle with no obvious involvement of the adjacent part of maxilla and mandible. Local wide excision of tumor was done. Histopathological examination revealed a malignant mesenchymal tumour. Further the specimen was subjected to immunohistochemical marker studies and diagnosis of high grade spindle cell sarcoma possibly synovial sarcoma was given. Patient then received Image guided radiation therapy and along with platinum based chemotherapy. Patient tolerated the treatment well. Patient was followed up for one year after completion of treatment and no recurrence was observed.

7.
Indian J Otolaryngol Head Neck Surg ; 75(2): 744-747, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37275096

RESUMEN

To evaluate various clinical signs and symptoms of Laryngopharyngeal reflux on the Larynx along with treatment outcome and to establish symptom-sign correlation. Prospective interventional study. 50 patients with symptoms and signs of LPR were enrolled in the study and were followed up for 9 months. Patients were evaluated with a 70° Hopkins rigid laryngoscope and the Reflux Symptom Index and Reflux Finding Score scales were used to grade the sign and symptoms and to diagnose LPR and to compare pre and post-treatment conditions. Patients were given treatments including PPI and diet modification. The most common laryngeal symptom based on the RSI score was sore throat (40%). Other common symptoms were hoarseness of voice (30%) and cough (20%). The most common laryngeal sign based on RFS (Reflux finding score) was Posterior Commissure Hypertrophy (40%). The other common signs were Pseudosulcus (30%), Vocal cord oedema (20%), and Granulomas (10%). Out of the 50 patients, 21 patients (42%) had an RFS score of less than 7. Rest 29 patients (58%) had RFS scores of more than 7. Out of these 29 patients, 19 patients (65.52%) had partial relief from symptoms after 3 weeks of treatment and were advised to take treatment for 3 more weeks, and rest 10 (34.48%) patients were completely unresponsive to treatment. The improvement in symptoms does not always manifest in improvement in signs and there is no correlation between the symptoms and signs of LPR.

8.
Indian J Otolaryngol Head Neck Surg ; 75(4): 4212-4215, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37974749

RESUMEN

ENT professionals are facing the heat of raised number of malpractice complaints against them. Some of them have a direct impact on surgeon's career & life progression. Lawsuits are not new to otology, but with evolution of education, social media & media trials etc., negativity is being generated against doctors each day. This article considers the causes, types & prevention of medicolegal malpractice claims/lawsuits against the doctors with incorporation of recent NMC guidelines for the same. Supplementary Information: The online version contains supplementary material available at 10.1007/s12070-023-04078-5.

9.
Indian J Otolaryngol Head Neck Surg ; 75(Suppl 1): 574-577, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37206766

RESUMEN

Thyroid hormone disorders are both congenital as well as acquired. According to a projection from several studies on thyroid diseases, it has been estimated that about 42 million people in India suffer from various kind of thyroid diseases (1) Thyroid hormone is closely associated with the development of the cognitive functions, thus deficiency of this hormone is said to have effect an overall impact on proper functioning of the body. The normal functioning of the thyroid gland and adequate levels in the blood are Needed for the formation and functioning of the middle ear, inner ear and the central auditory pathway. Thus, congenital hypothyroidism (CH) can be a potential risk factor for hearing impairment (2) if the hormones decrease or are absent during the development of the peripheral and central auditory system structures. This study was undertaken with the objective of studying the pattern of hearing loss in patients who have a deranged thyroid profile. The study was conducted among 50 patients who were known cases of thyroid disorder in the Otorhinolaryngology Department of our institute. The study was hospital based observational clinical study. The patients were subjected to thyroid profile test After this, those who satisfied the inclusion and exclusion criteria and were included, after detailed history and examination, patients were subjected to PTA, hearing loss was classified according to WHO guidelines. The age group of the patients was from 30-55 yrs. with the mean age being 42. On the basis of the t3, t4 and tsh levels, in the current study out of 50 patients,40 were hypothyroid (80%),with male to female ratio of 6:4. On pure tone audiometry, 15 patients had decreased hearing. The other 25 had normal hearing. The incidence of hearing loss in hypothyoroid patients in our study is 37.5%. On analaysis the PTA reports of these patients,9 patients (22.5%) had conductive hearing loss of mild variety, the mean value of hearing loss being 26.2 decibels. 2 (5%) patients had mixed variety of hearing loss, with sensorineural hearing loss at higher frequencies. All the remaining patients had sensorineural type of hearing loss, i.e., 10%. Of the 10 patients, that have hyperthyroidism 8 were female and 2 were male. 3 patients (30%) had hearing loss, all these 3 patients reported hearing losses at high frequencies and had moderate type of sensorineural hearing loss. Conclusion- From our current study, we could see that hearing loss is present in both extremes of thyroid hormone imbalance The dominant variety of hearing loss in thyroid disorder is sensorineural type, because thyroid hormone imbalance affects the inner ear function.

10.
Indian J Otolaryngol Head Neck Surg ; 74(Suppl 2): 3327-3332, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36105434

RESUMEN

Objective: To advocate a single stage reconstruction in cases of maxillectomy and midfacial defects operated for covid associated mucormycosis to enable a favorable overall outcome within a shorter duration in terms of survival, quality of life, speech, deglutition and aesthetics. Method: In our series of six patients with signs and symptoms suggestive of covid associated mucormycosis with diabetes as a predisposing factor had undergone Contrast enhanced CT and MRI with biopsy confirming the diagnosis, were then subsequently posted for resection and reconstruction depending upon extent of disease and defect left behind. Out of six, three were revision cases and the other three were primary cases. All had undergone single stage reconstruction using free flap (5/6) and pedicle (1/6) after intra-operative margins and distal most part of recipient vessels was found negative for mucormycosis on histopathology. Post-operative Liposomal Amphotericin B with Oral Posaconazole along with antibiotics and supportive treatment were given and were then followed up. Results: All the cases have complete flap survival after a mean follow-up of 90 days with no recurrence of mucormycosis. We had a survival rate of 100% with patients having good quality of life, speech, deglutition and acceptable aesthetical outcome. Conclusion: Stepping up on the reconstruction ladder to provide a single stage management in patients of covid associated mucormycosis by adequate surgical debridement, intraoperative negative margins on histopathology and subsequent reconstruction using autologous flaps is the need of the hour to provide within a shorter duration, favourable overall outcome in terms of survival, quality of life, speech, deglutition and aesthetics. Supplementary Information: The online version contains supplementary material available at 10.1007/s12070-022-03121-1.

11.
Indian J Otolaryngol Head Neck Surg ; 74(Suppl 2): 1518-1522, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36452749

RESUMEN

Functional endoscopic sinus surgery (FESS) is indicated for the treatment of chronic rhinosinusitis that is refractory to medical treatment. Nasal irrigation is a classic and powerful adjunctive method for the management of chronic rhinosinusitis after FESS [5]. This study aimed to compare the effects of hypertonic saline and isotonic saline nasal irrigation following endoscopic sinus surgery. The study was conducted in the Department of Otorhinolaryngology at Mahatma Gandhi Medical College and Hospital, Jaipur, India, on 156 patients, who had chronic rhinosinusitis with or without nasal polyposis, and were resistant to conservative management. All patients underwent functional endoscopic sinus surgery. Patients were advised to perform nasal douching post-surgery, and were randomly divided into two groups based on the douching solution they used. Group 1 was given hypertonic saline (3%) while Group 2 was given isotonic saline (0.9%). Patients were examined at weeks 1, 3 and 6 post-operatively. Outcomes of irrigation using both solutions were assessed by- 20-item Sino-Nasal Outcome Test (SNOT20) scores [13], Visual analogue scale (VAS) scores [1, 2], mucociliary clearance (MCC) assessment [14] and endoscopic examination. The group receiving hypertonic saline showed significant improvement in 20-item Sino-Nasal Outcome Test scores, Visual analogue scale scores and improvement of sino-nasal mucosa from polypoidal to cobblestone, in the follow up period. However improvement in mucociliary clearance and resolution of postoperative crustings was consistent in both groups. Hypertonic saline nasal irrigation post FESS brings greater benefits on symptom improvement and normalization of the sino-nasal mucosa over isotonic saline.

12.
Indian J Otolaryngol Head Neck Surg ; 74(Suppl 3): 4467-4471, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36742552

RESUMEN

Aim-To evaluate and compare the success rate of dry and wet temporalis fascia graft in tympanoplasty type I using an underlay technique and determine the effect of fibroblasts, if any on the success rate. Materials and methods-. STUDY DESIGN: A 3 year prospective, randomized, comparative study between 2019 and 2021. SETTING: Mahatma Gandhi University of Medical Sciences and Technology, Jaipur. SUBJECTS: 100 adult patients of either sex were taken in this study, ranging between 15 and 60 years who fulfilled inclusion and exclusion criteria. These patients were randomly divided into 2 groups of 50 each, one in dry graft and another in wet graft group. METHODS: A comparative analysis was done on the graft placement time, fibroblast count and hearing improvement postoperatively between the two groups. Results- The dry graft and wet graft groups had overall surgical success rates of 86 and 94 per cent, respectively; this finding was not statistically significant. A statistically significant high fibroblast count was observed in wet grafts, but it did not correlate with surgical success. Conclusion- A dry or wet temporalis fascia graft has no influence on the outcome of tympanoplasty type I.

13.
Indian J Otolaryngol Head Neck Surg ; 74(Suppl 3): 4405-4408, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36742797

RESUMEN

The aim of this study is to establish a relationship between vitamin D levels and benign paroxysmal positional vertigo (BPPV) and its recurrence; and to evaluate the remedial effect of vitamin D on BPPV. In a pilot study, 40 patients with clinically diagnosed posterior canal BPPV were evaluated, treated and were followed up for a period of 6 months at ENT Department of Mahatma Gandhi Medical College, Jaipur. All the patients with clinical diagnosis of posterior canal BPPV were tested for 25(OH)D levels at their 1st visit. Patients were divided in two groups after appropriate matching. Group A was given vitamin D supplementation along with canal repositioning manoeuvre (CRM) and group B were only treated by canal repositioning manoeuvre. Patients underwent neuro-otological assessment during follow up visits and recurrent attacks were recorded. This study was conducted on 40 patients with BPPV (26 females and 14 males). The average age was 50 years. Average serum of 25(OH)D at the first visit was (12.2 ng/ml) for group A, and (12.4 ng/ml) for group B, all patients had low serum level of 25(OH)D (below 20 ng/ml). Recurrent BPPV episodes, were significantly lower in group A than that of group B. We second the hypothesis that the patients with BPPV who have insufficient levels of Vitamin D may benefit from vitamin D supplementation and we suggest further epidemiological and pharmacological studies to detect the effect of vitamin D deficiency on development and recurrence of vertigo.

14.
J Assoc Physicians India ; 59: 424-8, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22315746

RESUMEN

BACKGROUND: Allergic rhinitis is a common upper respiratory tract inflammation associated with a significant morbidity in all the age groups. Fluticasone furoate is a new potent topical glucocorticoid for the treatment of allergic rhinitis. OBJECTIVE: To compare efficacy and safety of fluticasone furoate (FF) nasal spray 110 microg/day with fluticasone propionate (FP) nasal spray 200 microg/day for the relief of symptoms of allergic rhinitis in adult Indian patients. METHODS: Clinically symptomatic patients (n=220) with allergic rhinitis received treatment with FF or FP for 2 weeks in this comparative, open label, multicentric, clinical trial. Nasal symptoms (nasal congestion, rhinorrhea, nasal itching, and sneezing) and ocular symptoms (itching/burning eyes, tearing/watering eyes, and eye redness) were recorded on a 4-point categoric scale by the patients. The efficacy was assessed by the change in nasal and ocular symptom scores as their subtotals (Total Nasal Symptom Score and Total Ocular Symptom Score) and grand total (Total Symptom Score). RESULTS: FF produced significantly better improvement in Total Symptom Score (-10.4 +/- 3.2 vs. -8.9 +/- 3.5, p<0.005) and Total Nasal Symptom Score (-7.3 +/- 2.2 vs. -6.2 +/- 2.6, p<0.005) as compared to FP. Also a significantly larger percentage of patients achieved complete symptomatic relief with FF (45.3% vs. 31.4%, p<0.05). FF was also better tolerated than FP. CONCLUSION: FF nasal spray is significantly more effective and better tolerated than FP nasal spray for the treatment of allergic rhinitis in adult Indian patients.


Asunto(s)
Androstadienos/administración & dosificación , Antialérgicos/administración & dosificación , Rinitis Alérgica Estacional/tratamiento farmacológico , Administración Intranasal , Adolescente , Adulto , Anciano , Androstadienos/efectos adversos , Antialérgicos/efectos adversos , Niño , Relación Dosis-Respuesta a Droga , Femenino , Fluticasona , Humanos , India , Masculino , Persona de Mediana Edad , Rociadores Nasales , Resultado del Tratamiento
15.
Indian J Otolaryngol Head Neck Surg ; 73(2): 252-256, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34150600

RESUMEN

Cancer of the tongue forms more than 50% of oral cavity cancers. Generally, patients come with locally advanced tongue cancer. The treatment for this cancer is multi-modality. For resectable cancer, multiple surgical approaches are described in the literature. Mandibulotomy for resection of the middle and posterior third oral cancer is a well-established technique but it has its attended morbidity. We present our results of a new surgical technique, called the Peroral and submandibular cervical surgical approach wherein tongue cancer of middle third and posterior third is resected without mandibulotomy. The advantages of this technique are that the complications of malunion or non-union of bone are avoided, no chances of osteoradionecrosis or osteomyelitis, no need of periosteal elevation or damage, the malignancy is removed with wide margin with minimal blood loss, there is no scar on face or chin, morbidity of surgery is minimal. Also, the technique is easily reproducible.

16.
Biotechnol J ; 16(6): e2000212, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33484630

RESUMEN

BACKGROUND: CriPec technology enables the generation of drug-entrapped biodegradable core-crosslinked polymeric micelles (CCPM) with high drug loading capacity, tailorable size, and drug release kinetics. Docetaxel (DTX)-entrapped CCPM, also referred to as CPC634, have demonstrated favorable pharmacokinetics, tolerability, and enhanced tumor uptake in patients. Clinical efficacy evaluation is ongoing. CPC634 is currently stored (shelf life > 5 years) and shipped as a frozen aqueous dispersion at temperatures below -60°C, in order to prevent premature release of DTX and hydrolysis of the core-crosslinks. Consequently, like other aqueous nanomedicine formulations, CPC634 relies on cold chain supply, which is unfavorable for commercialization. Lyophilization can help to bypass this issue. METHODS AND RESULTS: Freeze-drying methodology for CCPM was developed by employing CPC634 as a model formulation, and sucrose and trehalose as cryoprotectants. We studied the residual moisture content and reconstitution behavior of the CPC634 freeze-dried cake, as well as the size, polydispersity index, morphology, drug retention, and release kinetics of reconstituted CPC634. Subsequently, the freeze-drying methodology was validated in an industrial setting, yielding a CPC634 freeze-dried cake with a moisture content of less than 0.1 wt%. It was found that trehalose-cryoprotected CPC634 could be rapidly reconstituted in less than 5 min at room temperature. Critical quality attributes such as size, morphology, drug retention, and release kinetics of trehalose-cryoprotected freeze-dried CPC634 upon reconstitution were identical to those of non-freeze-dried CPC634. CONCLUSION: Our findings provide proof-of-concept for the lyophilization of drug-containing CCPM and our methodology is readily translatable to large-scale manufacturing for future commercialization.


Asunto(s)
Micelas , Refrigeración , Liofilización , Humanos , Polímeros , Sacarosa
17.
Indian J Otolaryngol Head Neck Surg ; 71(Suppl 3): 1765-1769, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31763241

RESUMEN

Nasal packing is routinely used after septoplasty, but there are patient factors for which its use needs to be reconsidered. Effectiveness of nasal packing in trans-septal suturing technique in septoplasty. Prospective, comparative study, patients submitted to septoplasty were randomized to receive or not nasal packing postoperatively. Comparison in postoperative status for pain, headache, discomfort in swallowing, epiphora, bleeding, infection and pain on pack removal are assessed. In all the patients trans-septal suturing technique was used. Study group has 60 patients. Two groups were made group A in whom nasal packing done post operatively with merocel, group B in whom nasal packing was not done, in both groups quilting sutures were applied on to the septum. There was pain in nose and headache in all the patients in group A. Other symptoms in group A were epiphora, discomfort in swallowing due to ear discomfort. In addition to these there is pain on removal of packs. Routine use of nasal packing can be avoided instead sutures can be placed over the septum, which benefits in improving pain and symptoms due to pack in the postoperative period.

18.
Pharmaceutics ; 11(9)2019 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-31454967

RESUMEN

Poly(n-butyl cyanoacrylate) microbubbles (PBCA-MB) are extensively employed for functional and molecular ultrasound (US) imaging, as well as for US-mediated drug delivery. To facilitate the use of PBCA-MB as a commercial platform for biomedical applications, it is important to systematically study and improve their stability and shelf-life. In this context, lyophilization (freeze drying) is widely used to increase shelf-life and promote product development. Here, we set out to analyze the stability of standard and rhodamine-B loaded PBCA-MB at three different temperatures (4 °C, 25 °C, and 37 °C), for a period of time of up to 20 weeks. In addition, using sucrose, glucose, polyvinylpyrrolidone (PVP), and polyethylene glycol (PEG) as cryoprotectants, we investigated if PBCA-MB can be lyophilized without affecting their size, concentration, US signal generation properties, and dye retention. Stability assessment showed that PBCA-MB remain largely intact for three and four weeks at 4 °C and 25 °C, respectively, while they disintegrate within one to two weeks at 37 °C, thereby compromising their acoustic properties. Lyophilization analyses demonstrated that PBCA-MB can be efficiently freeze-dried with 5% sucrose and 5% PVP, without changing their size, concentration, and US signal generation properties. Experiments involving rhodamine-B loaded MB indicated that significant dye leakage from the polymeric shell takes place within two to four weeks in case of non-lyophilized PBCA-MB. Lyophilization of rhodamine-loaded PBCA-MB with sucrose and PVP showed that the presence of the dye does not affect the efficiency of freeze-drying, and that the dye is efficiently retained upon MB lyophilization. These findings contribute to the development of PBCA-MB as pharmaceutical products for preclinical and clinical applications.

19.
Indian J Otolaryngol Head Neck Surg ; 70(1): 15-21, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29456937

RESUMEN

Chronic suppurative otitis media, with and without cholesteatoma, frequently results in disruption of the ossicular chain. The present study was designed to compare the outcome using autologous ossicle and titanium prosthesis in two groups of suitable patients presenting with chronic suppurative otitis media for middle ear reconstructive surgeries. A prospective study done from July 2012 to December 2013, at Mahatma Gandhi Medical College and Hospital, Sitapura, Jaipur (Rajasthan). The target group included patients with chronic suppurative otitis media admitted and planned for reconstructive middle ear surgery. The study group patients among the target group requiring certain ossicular reconstruction. The patients included were patients with CSOM with or without cholesteatoma in which there was ossicular discontinuity. The patients were divided in two groups A and B. In group A patients autologous incus was used and in group B titanium prosthesis either TORP or PORP was used for ossicular replacement. Out of 340 patients as target group, 88 patients were included in study group. Further 88 patients of study group, 51 patients were included in group A; rest 37 patients were included in group B. In group B patients partial ossicular replacement platinum prosthesis was used in 31 patients while in rest 6 patients a total ossicular replacement prosthesis was used. Out of 88 patients, 79 were primary cases and 9 were revision cases. Pre and post operative air bone gap were noted. Pre operatively both of the groups were identical in relation to air-bone gap. The postoperative air-bone gap was calculated as the difference between postoperative air conduction and preoperative bone conduction. On comparison of preoperative and post-operative hearing results there was improvement in air conduction threshold and air bone gap in both the groups. Post operatively difference in air bone gap closure between group A and group B was found statistically significant (P value = 0.032) suggesting better hearing outcomes after using titanium ossicular replacement prosthesis. On comparing partial or total ossicular replacement prosthesis no significant difference was found for the audiological outcome (P = 0.434). Various prognostic factors were also noted for air bone gap closure. Titanium ossicular replacement prosthesis have better outcome, and no significant difference found in audiological outcome for TORP and PORP.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA