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1.
Orthod Craniofac Res ; 18 Suppl 1: 100-8, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25865538

RESUMEN

OBJECTIVES: To characterize soft-tissue facial height and width variation in Class II malocclusion and test for correlations with genes HMGA2, AJUBA, and ADK. SETTING AND SAMPLE POPULATION: Nine facial proportions were estimated from 2D frontal repose photographs of 330 Caucasian adults with Class II malocclusion. MATERIAL AND METHODS: After adjustments for age and gender, the facial proportions were submitted to a principal component analyses (PCA). The most meaningful phenotypic variations were correlated with SNPs rs7924176 (ADK), rs17101923 (HMGA2), and rs997154 (AJUBA) genotyped in 106 individuals. RESULTS: Principal component analyses resulted in four principal components (PCs), which explained 75% of total variation. PC1 captured variation in the intercanthus distance and explained 28% of total variation. PC2 explained 21% of the variations in facial taper and facial index. PC3 explained 14% and reflected variations in the vertical dimension of the lower face. PC4 explained 12% and captured variations in distance between the eyes, width of the commissures, and the length of the superior aspect of the lower face height corresponding to the vertical dimension of the philtrum of the upper lip. A suggestive association (p<0.05) was observed between PC4 and rs997154 corroborating the role of AJUBA in variation of facial dimensions. CONCLUSION: 2D frontal photographs can be used to derive quantitative measures of soft-tissue phenotypes that are of clinical relevance. The methods described are suitable for discovery and replication of associations between genotypes and malocclusion phenotypes.


Asunto(s)
Cara/patología , Maloclusión Clase II de Angle/patología , Dimensión Vertical , Adolescente , Adulto , Variación Anatómica/genética , Mentón/patología , Ojo/patología , Femenino , Genotipo , Proteína HMGA2/genética , Humanos , Proteínas con Dominio LIM/genética , Labio/patología , Masculino , Maloclusión Clase II de Angle/genética , Mandíbula/patología , Persona de Mediana Edad , Nariz/patología , Órbita/patología , Fenotipo , Fotograbar/métodos , Polimorfismo de Nucleótido Simple/genética , Análisis de Componente Principal , Proteínas Serina-Treonina Quinasas/genética , Proteínas Tirosina Quinasas/genética , Adulto Joven , Cigoma/patología
2.
Dent Clin North Am ; 66(2): 261-275, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35365277

RESUMEN

Clinical dental treatment is the most exacting and demanding medical procedure that persons with special needs undergo on a regular basis throughout their lifetime. Dental treatment is surgical in nature, usually requiring controlled placement of sharpened instrumentation in intimate proximity to the face, airway, and highly vascularized and inner aged oral tissues. Although approximately 90% of patients with special needs can and should be mainstreamed through any general dental practice, without significant behavioral guidance, techniques, or medical immobilization/protective stabilization, there has been a drastic shift toward pharmacologic management of these patients using various forms of sedation and general anesthesia.


Asunto(s)
Anestesia General , Restricción Física , Anciano , Humanos
3.
Spec Care Dentist ; 29(1): 39-50, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19152567

RESUMEN

Patients with special needs often present a challenge for the dental care team. The exacting and surgical nature of dental procedures requires significant patient cooperation to ensure the safe delivery of care. Some individuals who have special care needs have difficulty cooperating during treatment, thus creating a potentially harmful situation. Modern dentistry, particularly pediatric dentistry, provides the dental team with a variety of strategies designed to enable the team to safely provide comprehensive care in the least restrictive manner. These techniques range from tell-show-do, to medical stabilization, to general anesthesia. The effective use of noninvasive, nonpharmacologic behavioral guidance/support techniques cannot only avoid the need for sedation or general anesthesia, they can teach the patient to develop coping skills that may enable them to receive comprehensive care in a traditional dental setting over a lifetime. Unfortunately, many providers are inadequately trained in behavioral support strategies. This paper presents a review of noninvasive, nonpharmacologic behavioral support techniques with discussion regarding their application to persons with special care needs.


Asunto(s)
Anestesia Dental , Control de la Conducta , Sedación Consciente , Sedación Profunda , Atención Dental para Enfermos Crónicos , Atención Dental para la Persona con Discapacidad , Adaptación Psicológica , Anestesia General , Atención Odontológica Integral , Conducta Cooperativa , Relaciones Dentista-Paciente , Accesibilidad a los Servicios de Salud , Humanos
4.
Chemosens Percept ; 12: 115-124, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31827664

RESUMEN

INTRODUCTION: Measurements of chemosensory function within specific regions of the tongue can yield important information about the sensitivity of lingual areas to chemosensory stimuli, and may identify possible nerve damage. A novel regional chemosensory test that uses thin edible circles was developed for human testing. METHODS: Edible circles placed at six different regions of the tongue were used to examine regional sensitivity to quinine for bitter taste, NaCl for salt taste, sucralose for sweet taste, and capsaicin for pungency. The six regions included the anterior tip of the tongue, the left and right lateral margins of the tongue (anterior and posterior), and the circumvallate region. Testing was completed with the mouth open, and the mouth closed. RESULTS: Intensity ratings at all sites were higher in the closed mouth condition for the three taste stimuli. Quinine intensity was highest at the circumvallate region with the mouth closed. NaCl and sucralose intensity were highest at the anterior tip and circumvallate regions. Capsaicin intensity was most highly perceived at the anterior tip of the tongue, but open and closed mouth intensity ratings showed no significant differences. CONCLUSIONS: Regional differences in chemosensory perception were observed on the tongue, and these differences were dependent on the chemosensory stimulus, tongue region, and tasting mode. IMPLICATIONS: Edible circles show minimal diffusion with saliva, can be used to examine both taste and irritation, and may be used to identify regional papillae counts on the tongue. Finally, edible circles should be invaluable for examining damage to the oral cavity.

5.
J R Soc Interface ; 5(24): 801-6, 2008 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-17971319

RESUMEN

Electrochromic properties of spun films of bis[octakis(hexylthio)phthalocyaninato] dysprosium(III) were investigated for determining nicotinamide adenine dinucleotide hydride (NADH) in water solutions. A spin-coated film deposited on indium tin oxide electrode displays only one redox couple (at E1/2=0.78V). The films of [(C6H13S)8Pc]2Dy were modified chemically or electrochemically for the detection of reduced NADH in water solution. The modified film in the oxidized ([(C6H13S)8Pc]2Dy)+ form is believed to be reduced to its neutral form on interaction with NADH.


Asunto(s)
Indoles/química , Elementos de la Serie de los Lantanoides/química , Membranas Artificiales , NAD/análisis , Compuestos de Estaño/química , Electroquímica/métodos , Electrodos , Isoindoles , Oxidación-Reducción
7.
Biomed Mater Eng ; 17(5): 257-68, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17851168

RESUMEN

Ultra-High-Molecular-Weight-Polyethylene (UHMWPE) is the material of choice for one of the articulating surfaces in many total joint replacements, notably hip and knee prostheses. The various methods used by the orthopaedic biomaterials industry to sterilize and anneal UHMWPE components, and the resulting oxidation and crosslinking, affect the mechanical wear resistance properties in ways still unknown at the microscopic and molecular levels. Transmission electron microscopy and chemical pyrolysis were used to quantify crosslinking induced by gamma irradiation and annealing in air. Changes in lamellar stacking and the amount of crosslinking suggest two types of crosslinking: relatively unstable crosslinks in the amorphous region initially resulting from gamma irradiation which are later replaced by more thermally stable crosslinks resulting from rearrangements at the annealing temperature. Lamellar mobility, the ability of crystalline lamellae to flow in the material, is enhanced during the transition from one type of bond to the other, and this appears to optimize near eight hours of annealing time. Results from decomposition and percent crystallinity measurements provide further support for this theory.


Asunto(s)
Materiales Biocompatibles/química , Materiales Biocompatibles/efectos de la radiación , Polietilenos/química , Polietilenos/efectos de la radiación , Aire , Reactivos de Enlaces Cruzados/química , Rayos gamma , Dureza , Calor , Ensayo de Materiales , Conformación Molecular
9.
Rev Stomatol Chir Maxillofac Chir Orale ; 117(6): 411-420, 2016 Dec.
Artículo en Francés | MEDLINE | ID: mdl-27527660

RESUMEN

INTRODUCTION: Primary intraosseous carcinoma (PIOC) of the jaws is a rare epidermoid carcinoma from epithelial origin and initially strictly localized within the bone. Histologically, type 3 PIOC (PIOC3) is a de novo primary intraosseous carcinoma. Because of the rarity of this illness, we propose an analysis of a personal case and a revue of the literature. MATERIAL AND METHODS: Two search engines (Pubmed®, Sciencedirect®) were questioned over the period 1976-February 2016 by using following keywords carcinoma, intraosseous, jaws, squamous cell carcinoma. Articles reporting proven PIOC3 and mentioning a precise treatment were selected. RESULTS: Thirty articles concerning 54 patients (sex ratio: 2.4; mean age: 56.8; extreme: 24-78) met the inclusion criterions. The most common symptoms were swelling (53%), pain (44.9%) and infra-alveolar nerve paresthesia (30.6%). The time to diagnosis was 13 weeks. Classification of Zwetyenga et al. showed more than 80% of T2 and T3 stages. The lesions were predominantly mandibular (85.2%) and posterior. Less than a third of patients had lymph node and 10% had distant metastasis. Treatment consisted mostly in a combination of surgery and radiotherapy. With a mean follow-up of 74.8 months, 70.8% were in remission with no evidence of recurrence. We report the case of a 58-year-old patient, with no medical history, complaining since several months about periodontitis with teeth mobility in the right mandibular area. The panoramic X-ray showed a bone lysis at the place of tooth No. 46. In the absence of alveolar healing after extraction and antibiotherapy, a biopsy was made that diagnosed a differentiated keratinizing squamous cell carcinoma. CT scan and MRI showed a mandibular cortical bone loss with involvement of adjacent structures and lymphadenopathy in the ipsilateral IB area. The patient was treated with a combination of chemotherapy and surgery. Postoperative chemo- and radiotherapy is still going on. DISCUSSION: The PIOC3 is a rare tumor, mainly arising in males around 50. Diagnosis should be evoked in the presence of painful swelling and nervous symptoms. The time to diagnosis is long. Tumors are usually seen at late stages. Treatment classically combines surgery and radiotherapy.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Maxilomandibulares , Adulto , Anciano , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Femenino , Humanos , Neoplasias Maxilomandibulares/epidemiología , Neoplasias Maxilomandibulares/patología , Neoplasias Maxilomandibulares/terapia , Masculino , Persona de Mediana Edad , Adulto Joven
10.
J Biomed Mater Res B Appl Biomater ; 103(1): 106-15, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24771508

RESUMEN

A novel, sensitive method for quantifying an equivalent antioxidant concentration, specifically vitamin E (VE), in postprocessed ultra-high molecular weight polyethylene (UHMWPE) for orthopedic implants is presented. This method correlates oxidative-induction time (OIT) determined from differential scanning calorimetry with starting VE weight percent in solvent blended samples using a nonlinear power law fit. The generated calibration curve reliably determined the equivalent VE concentration down to blended concentrations lower than 0.007 wt %, with a measurement uncertainty of 0.0009 wt %. This measurement uncertainty implies a detection limit that is significantly lower than currently achievable with the established method using Fourier transform infrared spectroscopy to calculate a VE index. However, exact processes that are influencing the OIT in irradiated materials are unclear at this time. UHMWPE blended with VE in powder, consolidated and irradiated form were investigated. In addition, intralaboratory results give support that this technique may lend itself to standardization in quality control and verification.


Asunto(s)
Antioxidantes/química , Polietileno/química , Vitamina E/química , Rastreo Diferencial de Calorimetría , Prótesis e Implantes , Espectroscopía Infrarroja por Transformada de Fourier
11.
Biomaterials ; 5(5): 307-9, 1984 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6487714

RESUMEN

The effects of a few synthetic polymers on the motility of human spermatozoa in vitro have been studied. An alternate copolymer of styrene and maleic anhydride, poly(S-MA), poly (styrene-maleic acid), poly(S-MC), poly(hydroxy-ethyl methacrylate-methacrylic acid) copolymer, poly(HEMA-MAC), poly(HEMA) homopolymer and poly(MAC) homopolymer were chosen for this purpose. It was found that all the carboxylic acid containing polymers are strong inhibitors of the motility of spermatozoa. Poly(HEMA) did not have any inhibitory effect on the motility of spermatozoa.


PIP: This paper describes the effects of selected synthetic polymers on the motility of human spermatozoa in vitro. The authors have developed a new mehtod of male fertility control that involves the use of an anionic hydrophilic polymer which when infected into the vas deferens, is precipitated and lowers the pH in the vicinity, thus killing the spermatozoa passing through the vas deferens. The results of this experiment indicate that carboxylic acid-containing polymers are strong inhibitors of sperm motility. Almost all sperm became immotile within 15 minutes after treatment with polymer (styrene-maleic acid) (S-MC) and polymer methacrylic acid (MAC). Polymer (HEMA-MAC), a copolymer containing roughly equal ratios of hydroxyethyl methacrylate and methacrylic acid, showed inhibitory action, but it took 30 minutes for 100% immotility to be achieved. The stronger inhibition of motility observed with poly (S-MC) compared with poly (HEMA-MAC) is attributed to the presence in the former of 2 carboxylic groups on adjacent carbon atoms. It is possible that low pH environment created by ionization of carboxyl groups fixed in the polymer matrix is responsible for killing the spermatozoa. Hydrogen ion concentration is considered to be a key factor in influencing the motility, viability, and metabolism of spermatozoa. Poly (HEMA), containing only hydroxyl groups, did not have any inhibitory effect.


Asunto(s)
Anticonceptivos Masculinos , Polímeros/farmacología , Motilidad Espermática/efectos de los fármacos , Humanos , Técnicas In Vitro , Masculino , Maleatos/farmacología , Anhídridos Maleicos/farmacología , Ácidos Polimetacrílicos/farmacología , Poliestirenos/farmacología , Relación Estructura-Actividad
12.
Biomaterials ; 11(7): 473-6, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2242395

RESUMEN

Methacrylic acid (MAA) was radiation grafted on to poly(vinyl chloride) (PVC) films to improve the blood compatibility of PVC. The thromobogenicity of MAA grafted PVC was evaluated by thrombus formation, platelet adhesion and haemolytic activity in vitro. The hydrophilicity of grafted PVC films was investigated by contact angle measurement. Methacrylic acid grafted PVC film showed lower thrombogenicity than that of PVC. It was found that the weight of thrombus formed on grafted PVC was less than that of PVC and glass and decreased with the increase in the graft level. The adhesion of platelets on grafted PVC was retarded after grafting with MAA hydrogels.


Asunto(s)
Materiales Biocompatibles , Ensayo de Materiales , Metacrilatos , Polímeros , Cloruro de Polivinilo , Trombosis/etiología , Hemólisis , Humanos , Técnicas In Vitro , Adhesividad Plaquetaria/fisiología , Propiedades de Superficie
13.
Biomaterials ; 24(3): 443-9, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12423599

RESUMEN

Vancomycin encapsulation in biodegradable poly(epsilon-caprolactone) microparticles (200 microm mean diameter) was most efficient with a simple emulsion technique that dispersed 122.5 mg/g of polymer. Scanning electron micrographs showed smooth or pitted particles. Dissolution studies were correlated with microparticle morphology, indicating higher release with pitted particles when vancomycin was encapsulated in a dissolved state. The cytocompatibility of these poly(epsilon-caprolactone) microparticles was demonstrated by a direct contact cytotoxic assay. This material can be considered as an efficient drug delivery system for bone implantation.


Asunto(s)
Materiales Biocompatibles/farmacología , Caproatos/química , Caproatos/farmacología , Sistemas de Liberación de Medicamentos , Lactonas/química , Lactonas/farmacología , Vancomicina/farmacología , Implantes Absorbibles , Animales , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Sustitutos de Huesos , Línea Celular , Fibroblastos/metabolismo , Cinética , Ratones , Microscopía Electrónica de Rastreo , Espectrofotometría , Factores de Tiempo , Vancomicina/administración & dosificación
14.
Biomaterials ; 25(21): 5147-54, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15109838

RESUMEN

Biodegradable polymer scaffolds were prepared from chitosan with varying degree of deacetylation for in vitro culture of human breast cancer MCF-7 cell lines. These polymers were characterized in terms of functional groups by FTIR and swelling properties. Polymers having high degree of deacetylation showed better swelling properties irrespective of the molecular weight. These polymers were biocompatible and non-toxic towards human epithelial MCF-7 cell lines. Attachment kinetics of MCF-7 cell lines on to polymer scaffold was investigated and it was observed that polymer having high degree of deacetylation favored better cell attachment. In CPIII polymer scaffold having 80% degree of deacetylation, a maximum of 1 millions cells per mg pf polymer were adsorbed within 1h. It appears that high swelling and high degree of deacetylation of chitosan helped in better adsorption of cancer cell lines. The cellular morphology of the attached cells on chitosan matrix was similar to that observed with regular plastic culture with the difference that, cells grew as three-dimensional clumps on chitosan matrix. Polymer having high degree of deacetylation not only favored better adsorption but also showed improved cell growth kinetics. Maximum cell concentration of 6.5 x 10(5) cells/ml was achieved in 5 days culture on CPIII polymer scaffold. The glucose consumption and lactate production pattern of the MCF-7 cell lines on chitosan polymer matrix were similar to that observed on cell growth on tissue culture flask. These results indicate that chitosan scaffold having high degree of deacetylation can be used for three-dimensional growth of MCF-7 cancer cell lines. Such in vitro 3D culture of cancer cells can thus be used as a model for the cytotoxic evaluation of anticancer drugs.


Asunto(s)
Materiales Biocompatibles/química , Neoplasias de la Mama/patología , Neoplasias de la Mama/fisiopatología , Técnicas de Cultivo de Célula/métodos , Quitosano/química , Ingeniería de Tejidos/métodos , Adhesión Celular , División Celular , Línea Celular Tumoral , Supervivencia Celular , Humanos , Ensayo de Materiales , Propiedades de Superficie
15.
Biomaterials ; 22(20): 2785-94, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11545313

RESUMEN

Previous studies have shown the effectiveness of an injectable bone substitute (IBS) composed of biphasic calcium phosphate in 2% hydroxypropyl methylcellulose gel (50/50 w/w). A therapeutic agent in the form of a drug can be added to the biomaterial by encapsulation into microparticles to protect the active agent, control its release and preserve the material rheological properties. Poly(epsilon-caprolactone) was used in this study because of its biocompatibility and resorbability, as tested in orthopaedic implants and surgical sutures. Particles (80-200 microm) were manufactured by a solvent evaporation-extraction process (1 g of polymer, 11-15 ml methylene chloride, with a stirring speed of 400-600 rpm) and introduced into the IBS in a 5-50% (V/V) range. Injectability was evaluated by texture analysis. With less than 45% of particles, the material had rheological properties similar to those of the reference IBS, whereas injectability decreased markedly with more than 45% of particles. A preliminary in vitro release study showed that this type of triphasic IBS could be efficient for drug delivery systems with osteoconduction properties.


Asunto(s)
Materiales Biocompatibles , Sustitutos de Huesos , Fosfatos de Calcio , Poliésteres , Antibacterianos/administración & dosificación , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Vancomicina/administración & dosificación
16.
J Appl Physiol (1985) ; 69(2): 465-72, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2121700

RESUMEN

We hypothesized that agents very different from surfactant may still support lung function. To test this hypothesis, we instilled FC-100, a fluorocarbon, and Tween 20, a detergent, which have higher minimum surface tensions and less hysteresis than surfactant, into 15 full-term and 14 preterm lambs. FC-100 and Tween 20 were as efficient as natural surfactant in improving gas exchange and compliance in preterm lambs with respiratory failure. Dynamic compliance correlated with the equilibrium surface tension of the alveolar wash in both full-term (P less than 0.02) and preterm (P less than 0.008) lambs. Functional residual capacity in full-term and preterm lambs was lower after treatment with the two test agents than with surfactant, findings consistent with qualitative histology. Oxygenation in full-term lambs correlated with mean lung volumes (P less than 0.003), suggesting that the hysteresis and/or low minimum surface tension of surfactant may improve mean lung volume, and hence oxygenation, by maintaining functional residual capacity. The effects of the test agents suggest that agents with biophysical properties different from surfactant may still aid lung expansion.


Asunto(s)
Pulmón/efectos de los fármacos , Surfactantes Pulmonares/farmacología , Animales , Animales Recién Nacidos , Dióxido de Carbono/sangre , Femenino , Fluorocarburos/farmacología , Humanos , Recién Nacido , Pulmón/patología , Pulmón/fisiología , Pulmón/fisiopatología , Oxígeno/sangre , Polisorbatos/farmacología , Embarazo , Surfactantes Pulmonares/deficiencia , Síndrome de Dificultad Respiratoria del Recién Nacido/sangre , Síndrome de Dificultad Respiratoria del Recién Nacido/tratamiento farmacológico , Síndrome de Dificultad Respiratoria del Recién Nacido/fisiopatología , Ovinos
17.
J Pharm Sci ; 83(5): 632-5, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8071810

RESUMEN

Sustained release of ferrous sulfate (FeSO4) from gum arabica pellets has been achieved for 7 h. Release is further sustained for 12 to 600 h by coating the pellets with polyvinyl acetate and ethylene vinyl acetate, respectively. An increase in the amount of gum arabica in the pellets decreases the rate of release due to the gelling property of gum arabica. The gel layer acts as a barrier and retards the rate of diffusion of FeSO4 through the pellet. In coated pellets, an increase in thickness of membrane helps to sustain the release of FeSO4 for a longer duration. Thus, the release of FeSO4 can be sustained for the required duration by adjusting the amount of gum arabica in the pellet and the composition and thickness of polymeric coat. The mechanism of release accordingly varies from Fickian to zero-order and super case II transport.


Asunto(s)
Compuestos Ferrosos/administración & dosificación , Goma Arábiga/química , Polivinilos/química , Fenómenos Químicos , Química Farmacéutica , Química Física , Preparaciones de Acción Retardada , Difusión , Compuestos Ferrosos/química , Compuestos Ferrosos/farmacocinética , Membranas Artificiales
18.
J Pharm Sci ; 83(6): 845-51, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9120819

RESUMEN

In order to study the tissue distribution of biodegradable nanoparticles after oral administration in animals, end-chain-radiolabeled poly(D,L-lactides) were prepared. Two groups of polymers (Mn = 7500, I = 2.4 and Mn = 28000, I = 1.4 as determined by organic size-exclusion chromatography) were chemically modified by reaction of [14C]acetic anhydride with hydroxyl end-chain groups. The activities of both resulting radioactive poly(D,L-lactides) varied from 57 to 1140 microCi/g. Poly(D,L-lactide) or poly(D,L-lactide-co-glycolide) nanoparticles containing various amounts of radioactive polymer were prepared according to the solvent evaporation process with acetone as cosolvent with methylene chloride in the organic phase. Their mean diameter was 133 +/- 25 nm, measured by photon correlation spectroscopy. The radiolabeled-end-group stability of these particles in buffer solutions was found to be greater when the matrix was made from the radiolabeled poly(D,L-lactide) having the highest molecular weight and the lowest polydispersity index. The polymer-chain stability was totally retained for at least 1 week in a phosphate buffer, pH 7.4, i.e. for the selected experiment time.


Asunto(s)
Poliésteres/química , Radioisótopos de Carbono , Portadores de Fármacos , Estabilidad de Medicamentos , Peso Molecular
19.
Contraception ; 20(5): 467-73, 1979 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-43211

RESUMEN

A new contraceptive technique has been proposed and tested. The method uses a novel polymer which when injected into the vas deferens, lowers the pH sufficiently kill the spermatozoa passing through. The polymer itself does not degrade in the process but can be flushed out to regain fertility. Experiments carried out on rats demonstrate the efficacy of the technique so as to have non-surgical, non-occlusive and reversible male contraception.


PIP: A radically new technique of male injectable nonocclusive chemical contraception is presented which is claimed to be reversible, not conducive to immunological reactions, nonsurgical, and nonocclusive. The method basically involves infusion of a chemical agent into the vas deferens, but its basic principle of operation differs significantly from standard chemical techniques. A novel polymer was fabricated which when injected into the vas deferens does not affect the lumen and lowers pH sufficiently to kill any spermatozoa passing through the vas. In addition, the polymer does not degrade in the process but can be removed by flushing to reverse the spermicidal effects of its insertion. In vitro studies showed the pH to be as low as 3.5. In addition, in vitro spermicidal action of the polymer was tested, and each time the polymerized sperm were unable to uptake dye, confirming their death. Fertility trials, utilizing albino rats, proved the efficacy of this polymer in vivo: rats were treated with either normal saline solvent only (dimethyl sulfoxide), or dissolved polymer for 180 days, and at the conclusion of the trial, the fertility of saline-treated rats had 0% fertility. This technique has the potential for easy reversibility while not affecting the patency of vas deferens.


Asunto(s)
Anticonceptivos Masculinos/administración & dosificación , Animales , Femenino , Humanos , Concentración de Iones de Hidrógeno , Inyecciones , Masculino , Anhídridos Maleicos/administración & dosificación , Polímeros/administración & dosificación , Ratas , Estirenos/administración & dosificación , Conducto Deferente
20.
Indian J Exp Biol ; 40(9): 1038-42, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12587734

RESUMEN

Carbon, hydrogen and nitrogen analyses of banana leaf and pseudostem biomass revealed their potentiality as substrates for microorganisms. Infra-red (IR) spectra of both biomass show presence of cellulose, xylan and lignin. IR spectra of leaf and pseudostem biomass degraded in solid state fermentation (SSF) by two Pleurotus species (P. sajor-caju and P. ostreatus) for 40 days showed the utilization of cellulose, xylan and lignin by these microbes. Dynamics of various lignocellulolytic enzymes of Pleurotus species and analyses of carbon, hydrogen and nitrogen contents of degraded biomass supported the same. Both the Pleurotus species exhibited lignin consumption ability on both the substrates.


Asunto(s)
Carbono/análisis , Hidrógeno/análisis , Musa/metabolismo , Nitrógeno/análisis , Estructuras de las Plantas/metabolismo , Pleurotus/metabolismo , Basidiomycota/metabolismo , Biodegradación Ambiental , Biomasa , Celulosa/metabolismo , Fermentación , Lignina/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier
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