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1.
J Contemp Dent Pract ; 25(1): 72-78, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38514435

RESUMEN

AIM: In comparing the effectiveness and efficiency of different types of post removal systems in removing different types of fiber posts (FPs), this study aims to shed light on the success of removal by currently available drill systems. MATERIALS AND METHODS: A total of 200 maxillary first molars, were root canal treated and prepared to receive posts. The molars were divided into four groups corresponding to four different FPs: Group RX, Radix FP; Group RF, Reforpost Glass Fiber; Group HI; Hi-Rem Endodontic Post; and Group DT, D.T. Light-Post Illusion X-RO. Fiber posts were done with luting by Gradia Core (GC America, Inc.). Groups were again divided into five subgroups corresponding to the technique by which the FP was removed into as follows: Subgroup P, PD-25-1.1 Drill; subgroup G, GC FP Drill; subgroup E, EasyPost Precision Drill; subgroup R, Reaccess Carbide Double Taper Kit; and subgroup H; H-Endodontic Drill. After posts were removed, effectiveness and efficiency were documented. Data were tabulated and statistically analyzed. RESULTS: Strong significant differences regarding efficiency among groups (FP type) and subgroups (drills used) (p = 0.00) were shown by the one-way analysis of variance (ANOVA) test. Subgroup DT-G scored the longest mean removal time (20.9 minutes) while Subgroup RX-R scored the shortest mean removal time (1.4 minutes) Regarding effectiveness, strong significant differences among groups (p = 0.00) and subgroups (p = 0.00) were shown by one-way ANOVA. Subgroup RF-G scored the highest scale (5.2) whereas subgroup HI-R scored the lowest mean scale (1.2). CONCLUSION: The difference was strongly significant between tested post-removal kits and between tested FPs. Re-access Carbide Double Taper Kit performed superiorly in both effectiveness and efficiency, followed by PD-25-1.1 Drill. Hi-Rem post showed the best retrieving results among other FPs. CLINICAL SIGNIFICANCE: Knowing the best technique and tools for post removal could spare the practitioner any unwanted complications during post removal. How to cite this article: Sayed M, Alahmad AM, Alhajji KS, et al. Removal Efficiency and Effectiveness of Four Different Fiber Posts Using Five Different Drill Systems in Multirooted Teeth. J Contemp Dent Pract 2024;25(1):72-78.


Asunto(s)
Técnica de Perno Muñón , Diente no Vital , Humanos , Tratamiento del Conducto Radicular , Diente no Vital/terapia , Vidrio , Ensayo de Materiales , Cementos de Resina , Análisis del Estrés Dental
2.
Br J Dermatol ; 184(2): 226-236, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32956489

RESUMEN

Chronic urticaria (CU) affects about 1% of the world population of all ages, mostly young and middle-aged women. It usually lasts for several years (> 1 year in 25-75% of patients) and often takes > 1 year before effective management is implemented. It presents as chronic spontaneous urticaria (CSU), chronic inducible urticaria (CIndU) or both in the same person. More than 25% of cases are resistant to H1 -antihistamines, even at higher doses, and third- and fourth-line therapies (omalizumab and ciclosporin) control the disease only in two-thirds of H1 -antihistamine-resistant patients. Here we review the impact of CU on different aspects of patients' quality of life and the burden of this chronic disease for the patient and society. CU may have a strong impact on health-related quality of life (HRQoL), particularly when CSU is associated with angio-oedema and/or CIndU (Dermatology Life Quality Index > 10 in 30% of patients). Comorbidities, such as anxiety and depression, which are present in more than 30% of patients with CSU, compound HRQoL impairment. Severe pruritus and the unpredictable occurrence of weals and angio-oedema are responsible for sleep disorders; sexual dysfunction; limitations on daily life, work and sports activities; interfering with life within the family and in society; and patients' performance at school and work (6% absenteeism and 25% presenteeism). Apart from treatment costs, with annual values between 900 and 2400 purchasing power parity dollars (PPP$) in Europe and the USA, CU is associated with a high consumption of medical resources and other indirect costs, which may reach a total annual cost of PPP$ 15 550.


Asunto(s)
Urticaria Crónica , Urticaria , Enfermedad Crónica , Europa (Continente) , Femenino , Humanos , Persona de Mediana Edad , Omalizumab/uso terapéutico , Calidad de Vida , Urticaria/tratamiento farmacológico , Urticaria/epidemiología
3.
Eur Ann Allergy Clin Immunol ; 53(5): 228-233, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32551465

RESUMEN

Summary: Background. Sensitization to Salsola kali (Sk) weed pollen allergen is the most common cause of seasonal allergic rhinitis (SAR) in Middle East countries. Aim. To identify Salsola kali skin prick test (SkSPT) wheal size cut-off, able to determine true allergy among adult patients with moderate to severe SAR, who are in need of Salsola kali allergen specific immunotherapy (SkAIT). Methods. In 151 adults with moderate to severe SAR, mean age 32.79 ± 10.79 years, of both gender (females: 43.05%), with a positive SkSPT, (i.e., cut off wheal longest diameter of 3 mm) and one or more other local weed pollens, Salsola kali nasal provocation test (SkNPT) was carried out. Response was assessed both subjectively, with scores, and objectively, by measuring peak nasal inspiratory flow (PNIF). Safety profile of SkNPT was assessed using peak expiratory flow rate (PEF) measurements. Results. SkNPT positive response was found in 125 patients (82.78%). Mean skin prick test (SPT) wheal size to Sk was bigger in the nasal provocatin test (NPT) positive group (9 mm) compared to the NPT negative patients (5 mm), p less than 0.0001. ROC analysis showed that a SPT wheal size to Sk at the threshold of > 7.5 mm enabled identification of SkNPT positivity with a sensitivity of 73.6% and specificity of 100.0% (area under the curve 0.9498, standard error 0.01808; 95% confidence interval (CI): 0.9144 to 0.9853; p less than 0.0001). Conclusions. SPT wheal size of 3 mm might overestimate the presence of real allergy to Sk in a desert environment. A SPT wheal size > 7.5 mm for Sk appears to distinguish individuals who develop disease from those who does not. Physicians should select the proper SPT wheal size value as an appropriate criterion according to the allergen than using a uniform cut off value in patients eligible for SkAIT.


Asunto(s)
Hipersensibilidad , Salsola , Adulto , Alérgenos , Femenino , Humanos , Hipersensibilidad/diagnóstico , Inmunoglobulina E , Pruebas de Provocación Nasal , Pruebas Cutáneas/métodos , Adulto Joven
4.
Artículo en Inglés | MEDLINE | ID: mdl-28960180

RESUMEN

BACKGROUND: There are no studies on cross-reactivity between Salsola kali and Salsola imbricata pollens. The main goals of the present study were to compare the degree of the cross-reactivity between S kali and S imbricata and to compare the various allergenic components shared by S kali and S imbricata. METHODS: erum samples were obtained from rhinitis patients with or without asthma living in Kuwait and presenting with a positive skin test result to S kali. SDS-PAGE/IgE Western blot and ELISA inhibition assay were performed. RESULTS: The study population comprised 37 patients. The most frequent IgE proteins against S imbricata weighed around 12, 15, 18, 37, and 50+55 kDa. 2D electrophoresis revealed a correlation between S kali and S imbricata at 40, 60, and 75 kDa, with similar isoelectric points. ELISA inhibition revealed an Ag50 value of 1.7 µg/mL for S kali and 500.5 µg/mL for S imbricata when the solid phase was S kali and an Ag50 value of 1.4 µg/mL for S kali and 3.0 µg/mL for S imbricata when the solid phase was S imbricata. CONCLUSIONS: ELISA inhibition revealed strong cross-reactivity between S kali and S imbricata. This finding might be clinically relevant for the efficacy of allergen-specific immunotherapy. We report, for the first time, the allergenic profile of S imbricata and potentially allergenic proteins for S kali and S imbricata.


Asunto(s)
Reacciones Cruzadas/inmunología , Salsola/inmunología , Adolescente , Adulto , Alérgenos/inmunología , Antígenos de Plantas/inmunología , Desensibilización Inmunológica/métodos , Femenino , Humanos , Inmunoglobulina E/inmunología , Masculino , Persona de Mediana Edad , Proteínas de Plantas/inmunología , Polen/inmunología , Rinitis Alérgica Estacional/inmunología , Pruebas Cutáneas/métodos , Adulto Joven
5.
Eur Ann Allergy Clin Immunol ; 50(3): 125-131, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29479937

RESUMEN

Summary: Introduction. Sensitization to cat allergens is common worldwide. Currently, there is a trend towards costly and often unavailable diagnostic analysis. Objectives. The aim is to assess the reliability of skin prick test (SPT) and serum specific IgE (ssIgE) to cat sensitization, by performing nasal challenge test (NCT) in a community with low cat ownership but common presence of stray cats. Patients and methods. Forty-one pa-tients with perennial allergic rhinitis (AR) who were mono or polysensitized (including cat) were included. We had 31 cat non-owners and 10 present cat owners. SPT (> 5 mm / diameter), ssIgE (≥ 0.70 IU/ml), nasal smear for eosinophil (Eo) and NCT were compared between groups. Outcomes included nasal challenge score, nasal Eo positivity, peak inspiratory and expiratory flow (PIF and PEF) 2 and 8 hours after the NCT, and were compared to baseline. Results. Baseline SPT wheal size and ssIgE level were similar in both groups. NCT positivity was more frequent in cat owners. The strongest nasal reaction was on the top concentration in both groups. Nasal Eo positivity in cat owners was higher before and 2 hours after NCT, but similar to non-owners at last measurement. NCT positive cat non-owners had bigger SPT wheal size than NCT negative non-owners, but smaller than NCT positive cat owners. In contrast to PEF, a significant fall in PIF was noticed in both groups. Mono and polysensitised patients showed similar NCT positivity. Conclusion. Stray cats may pose a relevant risk of developing perennial AR. Regardless of cat ownership status, SPT and ssIgE should be the first diagnostic tool. Nasal Eo and NCT seem to be good diagnostic tools in cat non-owners if diagnosis is elusive.


Asunto(s)
Eosinofilia/sangre , Inmunoglobulina E/sangre , Pruebas de Provocación Nasal/métodos , Rinitis Alérgica Perenne/diagnóstico , Pruebas Cutáneas/métodos , Adolescente , Adulto , Alérgenos/inmunología , Pelaje de Animal/inmunología , Animales , Gatos , Eosinófilos/citología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rinitis Alérgica Perenne/sangre , Adulto Joven
6.
Eur Ann Allergy Clin Immunol ; 49(6): 276-280, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29249136

RESUMEN

SUMMARY: Introduction. There is no information regarding the pattern of inpatient referrals to drug allergy units in Kuwait. Objectives. The main goal of this study is to clarify the pattern of inpatient referrals to a drug allergy unit in terms of incidence, drugs implicated and allergy evaluation outcomes in comparison with studies in other countries. Patients and Methods. A retrospective chart review of inpatient drug allergy consultations at Al-Rashed Allergy Center over a 3-year period was performed. Results. A total of 51 patients were referred for drug allergy consultations, with an estimated incidence of reported drug allergy among inpatients of 0.008%. There is an increasing trend of referrals from public health centres located in proximity to Al-Rashed Allergy Center. Beta-lactams, contrast media, and general anaesthetics were the most common drugs leading to referrals. In total, 30% of patients were diagnosed with an allergy to the offending drug after a full allergy evaluation. Conclusion. Inpatient drug allergy referrals are highly underreported in Kuwait.


Asunto(s)
Hipersensibilidad a las Drogas/diagnóstico , Unidades Hospitalarias/tendencias , Pruebas Inmunológicas/tendencias , Pacientes Internos , Pautas de la Práctica en Medicina/tendencias , Derivación y Consulta/tendencias , Adulto , Anciano , Niño , Hipersensibilidad a las Drogas/epidemiología , Hipersensibilidad a las Drogas/inmunología , Hipersensibilidad a las Drogas/terapia , Femenino , Humanos , Incidencia , Kuwait/epidemiología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Adulto Joven
7.
J Econ Entomol ; 108(2): 425-32, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26470153

RESUMEN

This work is the first study to investigate the efficacy of the commercial formulation of Beauveria bassiana (Broadband) to control adults of red palm weevil (Rhynchophorus ferrugineus (Olivier)). This fungus could be applied as one of the biological tactics in controlling red palm weevil. Bioassay experiments for medium lethal concentrate and medium time to cause death of 50% of red palm weevil adults were carried out. The result showed that the LC50 of B. bassiana (Broadband) was 2.19×10(7) and 2.76×10(6) spores/ml at 9 and 23 d of treatment, respectively. The LT50 was 13.95 and 4.15 d for concentration of 1×10(7) and 1×10(8) spores/ml, respectively, whereas 1×10(9) spores/ml caused 100% mortality after 24 h. Additionally, a red palm weevil pheromone trap was designed to attract the adults to be contaminated with spores of Broadband, which was applied to the sackcloth fabric that coated the internal surfaces of the bucket trap. The mating behavior was studied to determine direct and indirect infection of the spores from male to female and vice versa. The results showed a high efficacy of Broadband suspension at 1×10(9) spores/ml; 40 ml of suspension at this concentration treated to cloth in a trap caused death of contaminated adults with B. bassiana spores directly and indirectly. The 100% mortality was obtained even after 13 d of traps treatment with 40 ml of the suspension at 1×10(9) spores/ml.


Asunto(s)
Beauveria , Control de Insectos/métodos , Control Biológico de Vectores , Gorgojos/microbiología , Animales , Femenino , Dosificación Letal Mediana , Masculino , Feromonas
8.
Allergy ; 65(2): 245-55, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19796210

RESUMEN

BACKGROUND: Mould-attributed symptoms have included features which overlap with unexplained syndromes such as sick building syndrome. OBJECTIVES: We describe questionnaire and chart review findings in patients following exposure to moulds which include Stachybotrys and compare responses with two control groups. METHODS: Thirty-two patients presented with symptoms attributed to mould exposures. Exposure identification for 25 patients had reported S tachybotrys chartarum as well as other mould (Aspergillus, Penicillium), 88% at work. The remaining seven had professionally visualized or self-reported/photographic exposure evidence only. A chart review was performed and a follow-up with a questionnaire, including questions on current health status, and nonspecific symptoms. RESULTS: Cough, shortness of breath and chest tightness (at presentation) were reported in 79%, 70% and 64%, respectively, and persisted >6 weeks in 91%. Skin test(s) were positive to fungal extract(s) in 30%. Seventeen returned questionnaires were obtained 3.1 (SD 0.5) years after the initial clinic assessment. Among this subgroup, persisting asthma-like symptoms and symptoms suggestive of sick building syndrome were frequent, and similar to a group previously assessed for darkroom disease among medical radiation technologists. The mould-exposed group more commonly reported they were bothered when walking in a room with carpets, complained of a chemical or metallic taste in their mouth, and had problems in concentration when compared with a control physiotherapist group (P < 0.005). CONCLUSIONS: Although only a minority with health concerns from indoor mould exposure had demonstrable mould-allergy, a significant proportion had asthma-like symptoms. Other symptoms were also common and persistent after the initial implicated exposure.


Asunto(s)
Hongos/inmunología , Hipersensibilidad/inmunología , Síndrome del Edificio Enfermo/inmunología , Contaminación del Aire Interior/efectos adversos , Femenino , Humanos , Hipersensibilidad/fisiopatología , Masculino , Persona de Mediana Edad , Pruebas de Función Respiratoria , Síndrome del Edificio Enfermo/fisiopatología , Pruebas Cutáneas , Encuestas y Cuestionarios
9.
J Investig Allergol Clin Immunol ; 20(3): 259-62, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20635793

RESUMEN

Idiopathic thrombocytopenic purpura (ITP) is a common autoimmune disease in patients with common variable immunodeficiency (CVID). We describe a 36-year-old woman with CVID. The clinical course of her disease was complicated by bronchiectasis, antiphospholipid antibody syndrome, and portal vein thrombosis. She developed recurrent attacks of ITP refractory to high doses of corticosteroid, intravenous immunoglobulin (IVIG), and splenectomy. She received a total of 5 doses of rituximab (375 mg/m2) and achieved an immediate and persistent response. Therapy was well tolerated. Her platelet count remained above 370,000/microL for 8 months of follow-up, despite repeated infections. During this period the patient remained off corticosteroids and on continuous IVIG replacement therapy.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Inmunodeficiencia Variable Común/complicaciones , Factores Inmunológicos/uso terapéutico , Púrpura Trombocitopénica Idiopática/complicaciones , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Adulto , Anticuerpos Monoclonales de Origen Murino , Inmunodeficiencia Variable Común/inmunología , Femenino , Humanos , Recuento de Plaquetas , Púrpura Trombocitopénica Idiopática/inmunología , Rituximab
10.
Nanotechnology ; 20(37): 375203, 2009 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-19706943

RESUMEN

This paper shows that we can print on paper simple high-frequency electronic devices such as resistances, capacitances or inductances, with values that can be changed in a controllable manner by an applied dc voltage. This tunability is achieved with the help of an ink containing functionalized carbon nanotubes and water. After the water is evaporated from the paper, the nanotubes remain steadily imprinted on paper, showing a semiconducting behavior and tunable electrical properties.


Asunto(s)
Electroquímica/métodos , Nanotecnología/métodos , Nanotubos de Carbono/química , Papel , Microscopía Electrónica de Rastreo , Modelos Teóricos
11.
Theriogenology ; 69(4): 473-80, 2008 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-18082249

RESUMEN

The aim of this study was to determine the infectious status of semen and genital tract tissues from male goat naturally infected with the caprine lentivirus. Firstly, polymerase chain reaction (PCR) was used to detect the presence of CAEV proviral-DNA in the circulating mononuclear cells, semen (spermatozoa and non-spermatic cells), and genital tract tissues (testis, epididymis, vas deferens, and vesicular gland) of nine bucks. RT-PCR was used to detect the presence of CAEV viral RNA in seminal plasma. Secondly, in situ hybridization was performed on PCR-positive samples from the head, body, and tail of the epididymis. CAEV proviral-DNA was identified by PCR in the blood cells of 7/9 bucks and in non-spermatic cells of the seminal plasma of 3/9 bucks. No CAEV proviral-DNA was identified in the spermatozoa fraction. The presence of CAEV proviral-DNA in non-spermatic cells and the presence of CAEV in the seminal plasma was significantly higher (p<0.01) in bucks with PCR-positive blood. Two of the three bucks with positive seminal plasma cells presented with at least one PCR-positive genital tract tissue. Proviral-DNA was found in the head (3/9), body (3/9), and tail (2/9) of the epididymis. In situ hybridization confirmed the presence of viral mRNA in at least one of each of these tissues, in the periphery of the epididymal epithelium. This study clearly demonstrates the presence of viral mRNA and proviral-DNA in naturally infected male goat semen and in various tissues of the male genital tract.


Asunto(s)
Virus de la Artritis-Encefalitis Caprina/genética , ADN Viral/análisis , Genitales Masculinos/virología , Cabras/virología , Semen/virología , Animales , Virus de la Artritis-Encefalitis Caprina/aislamiento & purificación , Hibridación in Situ , Masculino , Reacción en Cadena de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
12.
Theriogenology ; 69(4): 408-15, 2008 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-18036653

RESUMEN

The aim of this study was to demonstrate that embryo transfer can be used to produce CAEV-free kids from CAEV-infected biological mothers when appropriate procedure is implemented. Twenty-eight goats that had tested positive for CAEV using PCR on vaginal secretions were used as embryo donors. Embryos with intact-ZP were selected and washed 10 times; they were then frozen and used for transfer into CAEV-free recipient goats. Nineteen of the 49 recipient goats gave birth, producing a total of 23 kids. Three blood samples were taken from each recipient goat, 10 days before, during, and 10 days after parturition; these were tested for CAEV antibodies using ELISA and for CAEV proviral DNA using PCR. The mothers were then euthanized. Tissue samples were taken from the lungs, udder, and retromammary and prescapular lymph nodes. The kids were separated from their mothers at birth. Seven of them died. At 4 months of age, 16 kids were subjected to drug-induced immunosuppression. Blood samples were taken every month from birth to 4 months of age; samples were then taken on days 15, 21, and 28 after the start of the immunosuppressive treatment. The kids were then euthanized and tissue samples taken from the carpal synovial membrane, lung tissue, prescapular lymph nodes, inguinal and retromammary lymph nodes, and uterus. All samples from the 19 recipient goats and 23 kids were found to be negative for CAEV antibodies and/or CAEV proviral DNA. Under acute conditions for infection this study clearly demonstrates that embryo transfer can be safely used to produce CAEV-free neonates from infected CAEV donors.


Asunto(s)
Virus de la Artritis-Encefalitis Caprina , Transferencia de Embrión/veterinaria , Enfermedades de las Cabras/transmisión , Enfermedades de las Cabras/virología , Infecciones por Lentivirus/veterinaria , Animales , Virus de la Artritis-Encefalitis Caprina/genética , Criopreservación , ADN Viral/análisis , Femenino , Enfermedades de las Cabras/prevención & control , Cabras , Infecciones por Lentivirus/prevención & control , Infecciones por Lentivirus/transmisión , Reacción en Cadena de la Polimerasa , Embarazo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Riesgo , Recolección de Tejidos y Órganos/veterinaria
13.
Reprod Domest Anim ; 43(4): 429-36, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18179634

RESUMEN

To improve the results obtained with a reference cryopreservation extender (control extender: Triladyl + 20% (v/v) egg yolk + 6.4% (v/v) glycerol) for freezing caprine semen, glutamine was added to 18 split ejaculates at concentrations of 0, 20, 40, 80 and 120 mM (experiment 1). In experiment 2, glutamine was added to 18 split ejaculates at concentrations of 20, 25, 30, 35 and 40 mM. In the third experiment, the egg yolk was replaced with the low-density lipoprotein (LDL) fraction of egg yolk. The quality of frozen then thawed spermatozoa in each extender was compared using computer-assisted semen analysis. In experiment 1, glutamine at concentrations of 20 mm and 40 mm significantly improved sperm motility compared with the control extender. However, at 120 mM, a significant decrease in motility and velocity was observed. In experiment 2, motility, curvilinear velocity and amplitude of lateral head displacement (ALH) were improved in glutamine at 25 mM compared with the control. In experiment 3, 8% LDL and 25 mM glutamine significantly improved sperm motility, straight line velocity and ALH. In the fourth experiment, the quality of the previously defined freezing extender (Triladyl + 8% (v/v) LDL + 25 mM glutamine + 6.4% (v/v) glycerol) was tested by comparing acrosome, tail membrane, plasma membrane and DNA integrity in 18 split ejaculates of frozen then thawed spermatozoa with spermatozoa that had been frozen then thawed in the control extender, and with spermatozoa from fresh, unfrozen sperm. The percentage of spermatozoa with intact acrosomes and tail membranes was significantly higher with the newly defined extender than that observed with the control extender. There was no significant difference in the percentage of spermatozoa with intact DNA between the frozen and fresh semen.


Asunto(s)
Criopreservación/veterinaria , Glutamina/farmacología , Cabras , Lipoproteínas LDL/farmacología , Preservación de Semen/veterinaria , Semen , Acrosoma/efectos de los fármacos , Acrosoma/fisiología , Reacción Acrosómica/efectos de los fármacos , Reacción Acrosómica/fisiología , Animales , Criopreservación/métodos , Crioprotectores/farmacología , Relación Dosis-Respuesta a Droga , Yema de Huevo/química , Cabras/fisiología , Masculino , Semen/citología , Semen/efectos de los fármacos , Semen/fisiología , Preservación de Semen/métodos , Motilidad Espermática/efectos de los fármacos , Motilidad Espermática/fisiología , Espermatozoides/efectos de los fármacos , Espermatozoides/fisiología
14.
J Biomed Mater Res A ; 82(4): 777-87, 2007 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-17326141

RESUMEN

In vitro studies about the growth behavior of osteoblasts onto biomaterials is a basic knowledge and a screening method for the development and application of scaffolds in vivo. In this in vitro study human osteoblast-like (HOB) cells were cultured on seven different biomaterials used in dental and craniomaxillofacial surgery, respectively. The tested biomaterials were synthetic biodegradable (MacroPore, Ethisorb, PDS, Beriplast P) and nonbiodegradable polymers (Palacos) as well as calcium phosphate cement (BoneSource) and titanium. The cell proliferation and cell colonization were analyzed by scanning electron microscopy and EZ4U-test. Statistical analysis were performed. HOB-like cells cultivated on Ethisorb showed the highest proliferation rate. The proliferation rate was statistically significant compared with Palacos, MacroPore, and BoneSource. Whereas, Beriplast, PDS, and titanium yielded lower proliferation rates. However, there was no statistically significant difference compared with Palacos, MacroPore, and BoneSource. SEM analysis showed no significant difference in individual cell features and cell colonization. But an infiltration and a growth of HOB-like cells throughout the porous structure of Ethisorb, which is formed by crossing fibers, is a striking different feature (macrotopography). This feature can explain the highest proliferation rate of Ethisorb. The results showed that HOB-like cells appear to be sensitive to substrate composition and topography. Moreover, the basis for further studies with such biomaterial/osteoblast constructs in vivo are provided. Further focusing points are developing techniques to fabricate three-dimensional porous biomaterial/cell constructs, studying the tissue reaction and the bone regeneration of such constructs compared with the use of autologous bone.


Asunto(s)
Materiales Biocompatibles , Osteoblastos/citología , Fosfatasa Alcalina/metabolismo , Sustitutos de Huesos , Proliferación Celular , Colágeno Tipo I/metabolismo , Materiales Dentales , Adhesivo de Tejido de Fibrina , Humanos , Hidroxiapatitas , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Osteoblastos/metabolismo , Osteocalcina/metabolismo , Polidioxanona , Polimetil Metacrilato , Ingeniería de Tejidos , Titanio
15.
J Biomed Mater Res A ; 83(4): 1154-1164, 2007 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-17595023

RESUMEN

Reconstruction of bone defects in the field of craniomaxillofacial surgery is a relevant problem. In regenerative medicine, autologous bone is not available sufficiently. The full replacement of autologous bone grafts is required. A promising research field is the bone engineering. Especially the application of rapid prototyping (RP) enables new perspectives concerning the scaffold design. The aim of the study was to compare scaffolds produced by RP-technology (native and plasma-coated PLGA-scaffolds) with conventionally produced scaffolds (agar plates with hydroxyapatite and hyaluronic acid coated agar plates with hydroxyapatite) relating to proliferation, adhesion, and morphology of osteoblasts to get knowledge about the application potential of such 3D-manufactured matrices for bone engineering. TissueFoil E served as reference. To compare the scaffolds, 12 ovine and 12 human osteoblast-like cell cultures of the skull were used. Results were obtained by EZ4U, scanning electron microscopy, and light microscopy. The highest cell proliferation rate of human osteoblast-like cells was measured on TissueFoil E followed by plasma-coated PLGA-scaffolds and uncoated PLGA-scaffolds, whereas of ovine osteoblast-like cells on plasma-coated PLGA-scaffolds followed by TissueFoil E and uncoated PLGA-scaffolds. Human and ovine osteoblast-like cells on coated and uncoated agar plates had significant lower proliferation rates compared with TissueFoil E and PLGA-scaffolds. These results showed the potential of RP in the field of bone engineering. Mechanical properties of such scaffolds and in vivo studies should be investigated to examine if the scaffolds hold up the pressure it will undergo long enough to allow regrowth of bone and to examine the revascularization.


Asunto(s)
Huesos , Proliferación Celular , Osteoblastos/citología , Fosfatasa Alcalina/metabolismo , Animales , Colágeno Tipo I/metabolismo , Humanos , Microscopía Electrónica de Rastreo , Osteoblastos/enzimología , Osteoblastos/metabolismo , Ovinos , Ingeniería de Tejidos
16.
Tissue Cell ; 38(5): 337-44, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17010402

RESUMEN

Distinguishing features of biological constructions are high stability and adaptation to their environment. Beside biocompatibility, nontoxicity and degradability these characteristics are demanded for new biomaterials in the field of tissue engineering. This study investigated the chemical composition, the organization and the in vitro osteoconductive potential of the terrestrial gastropod shell (Helix pomatia) on CAL72 and human osteoblast-like cells. Chemical composition of the biomaterial was examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM) was performed to analyze the architecture of the snail shell and the morphology of the seeded cells. A double staining procedure (FDA/PI) and a proliferation test (EZ4U) assessed the viability of the cells. Microscopical images showed the multilayered architecture of the aragonite shell with hexagonal crystals on the inner side. The cells spread well on the biomaterial and the highest proliferation rate could be measured with CAL72 cells on the inner shell surface. The osteoconductive effects of this natural biomaterial could encourage further experiments in the field of tissue engineering.


Asunto(s)
Materiales Biocompatibles/química , Sustitutos de Huesos/química , Caracoles Helix/química , Caracoles Helix/ultraestructura , Ingeniería de Tejidos/métodos , Animales , Matriz Ósea/fisiología , Matriz Ósea/ultraestructura , Carbonato de Calcio/química , Carbonato de Calcio/uso terapéutico , Fosfatos de Calcio/química , Fosfatos de Calcio/uso terapéutico , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular/fisiología , Humanos , Microscopía Electrónica de Rastreo , Osteoblastos/fisiología , Osteoblastos/ultraestructura , Osteogénesis/fisiología , Ingeniería de Tejidos/tendencias , Diente/química , Diente/ultraestructura , Diente Artificial/tendencias , Difracción de Rayos X
17.
J Biomed Mater Res B Appl Biomater ; 74(1): 627-35, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15889436

RESUMEN

In this in vivo and in vitro study on resorbable (Monocryl and nonresorbable (Deknalon) monofilament sutures used in intraoral dentoalveolar surgery the bacterial colonization was compared. For the in vivo study the sutures were applied in 11 patients during dental surgery. Eight days postoperative the sutures were removed and the adhered bacteria were isolated and identified by biochemistry, morphology, antibiotic susceptibility, and gas chromatography. The colonization was studied by scanning electron microscopy. Aerobic and anaerobic bacteria were isolated in nearly equal colony-forming units (cfu) on each suture. In comparison with Monocryl about 15% more aerobic and anaerobic strains were isolated on Deknalon. Regarding the pathogens only, about three times more anaerobic strains were isolated on both sutures in total. Additionally, more pathogens were found on Deknalon than on Monocryl (aerobic >40%, anaerobic >25%). The variety of bacteria correspond with purulent infections, not with normal oral flora. Intraindividual comparisons of cfu showed differences in dependence of the patient as described for subgingivale plaques. For the in vitro study the sutures were incubated with Streptococcus intermedius and Prevotella intermedia for 0.5 h. Scanning electron microscopy was performed to examine qualitatively the level of bacterial adherence. After 0.5 h the bacteria adhered very well. The colonization rate of Streptococcus intermedius on both sutures was similar. Coccoid bacteria within biofilms were seen. The growth of Prevotella intermedia was much better on Deknalon than on Monocryl. The risk of bacteremia at the time of suture removal is discussed.


Asunto(s)
Materiales Biocompatibles/química , Implantes Dentales/microbiología , Dehiscencia de la Herida Operatoria , Infección de la Herida Quirúrgica , Bacterias/ultraestructura , Adhesión Bacteriana , Biopelículas , Cromatografía de Gases , Dioxanos/química , Humanos , Microscopía Electrónica de Rastreo , Nylons , Poliésteres/química , Complicaciones Posoperatorias , Prevotella intermedia/metabolismo , Riesgo , Células Madre , Streptococcus intermedius/metabolismo , Técnicas de Sutura , Suturas , Factores de Tiempo
18.
Theriogenology ; 64(7): 1656-66, 2005 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-15885763

RESUMEN

The aim of this study was to determine whether oocytes taken from ovarian follicles in 123 naturally infected goats were carrying the proviral CAEV genome. Examination of DNA isolated from 190 batches of oocytes with intact cumulus cells and 190 batches of oocytes whose cumulus cells had been removed, taken from follicles of the same ovaries, demonstrated that 42/190 batches of oocytes with intact cumulus cells had the proviral CAEV genome, whereas none of the 190 batches of oocytes without cumulus cells were positive for the provirus. To confirm that the proviral genome was present in the cumulus cells and not in the oocyte cells, 586 oocytes from 56 different ovaries, were separated from their cumulus cells. The DNA was then extracted from each fraction and examined. The purity of the oocyte fraction was verified by searching for granulosa cell-specific mRNA, using RT-PCR; this was negative in all the batches of oocytes in which the cumulus cells had been removed. PCR analysis demonstrated that none of the oocytes without cumulus cells were positive, whereas 22/56 of the batches with cumulus cells were found to be positive. This study clearly demonstrates that despite being surrounded by infected cumulus cells, the oocytes are not infected, and that the enzymatic and mechanical technique for removing the cells surrounding the oocyte, as used in this study, is effective, thus enabling CAEV-free oocytes to be obtained from infected goats.


Asunto(s)
Virus de la Artritis-Encefalitis Caprina/genética , ADN Viral/análisis , Enfermedades de las Cabras/virología , Infecciones por Lentivirus/veterinaria , Oocitos/virología , Folículo Ovárico/virología , Animales , Femenino , Cabras , Infecciones por Lentivirus/transmisión , Infecciones por Lentivirus/virología , Reacción en Cadena de la Polimerasa , Provirus/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
19.
Biomaterials ; 22(20): 2799-809, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11545315

RESUMEN

The adhesion, orientation and proliferation of human gingival epithelial cells and human maxillar osteoblast-like cells in primary and secondary culture were studied on glossy polished, sandblasted and plasma-sprayed titanium surfaces by scanning electron microscopy and in thin sections. The primary cultured explants of human gingival epithelial cells attached, spread and proliferated on all titanium surfaces with the greatest extension on the polished and the smallest extension on plasma-sprayed surfaces. In secondary suspension cultures of gingival keratinocytes, attachment spreading and growth was only observed on polished and plasma-sprayed surfaces, but not on sandblasted surfaces. Moreover, the attachment of these cells depended on the seeding concentration as well as on the coating with fetal calf serum. Cells on polished surfaces developed an extremely flat cell shape, but on sandblasted and plasma-sprayed surfaces a more cuboidal shape. In contrast human maxillar osteoblasts seeded as secondary suspension cultures attached very well to all three differently textured titanium surfaces and showed identical growth patterns independent of the titanium surface structure. These findings suggest that cell morphology, orientation, proliferation and adhesion of human gingival epithelial cells in primary or secondary culture are dependent on the texture of the titanium surface whereas no such differences were observed for maxillar osteoblast-like cells. In conclusion, the soft tissue integration and response is more influenced by the surface texture than the process of osseointegration.


Asunto(s)
Adhesión Celular , División Celular , Encía/citología , Queratinocitos/citología , Maxilar/citología , Osteoblastos/citología , Titanio , Fosfatasa Alcalina/metabolismo , Células Cultivadas , Colágeno/metabolismo , Medios de Cultivo , Implantes Dentales , Ensayo de Inmunoadsorción Enzimática , Encía/metabolismo , Encía/ultraestructura , Humanos , Inmunohistoquímica , Técnicas In Vitro , Queratinocitos/metabolismo , Queratinocitos/ultraestructura , Microscopía Electrónica de Rastreo , Osteoblastos/enzimología , Osteoblastos/metabolismo , Osteoblastos/ultraestructura , Propiedades de Superficie
20.
Biomaterials ; 23(16): 3319-28, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12099274

RESUMEN

The optimization of seeding and culturing of human osteoblast-like cells on three collagen-based biomaterials (bovine, equine and calf collagen membrane) was studied by cell proliferation and cell colonization (scanning electron microscopy) analysis. Osteoblasts of five patients were seeded onto the three biomaterials and two different parameters were varied: the time intervals between initial seeding and adding culture medium (2 h 6 h. 12 h, 24 h) and the seeding concentration (1 x 10(5), 1 x 10(6), 2 x 10(6)cells/ml) of cells onto biomaterials. The results of the study demonstrated that the time interval between seeding osteoblasts and adding culture medium as well as the seeding concentration effects the cell proliferation and the cell colonization. The best proliferation rate was achieved by adding the culture medium 2 h after initial seeding and with a seeding density of 1 x 10(5) cells/ml. Moreover, all three biomaterials resulted in different proliferation rates. The best proliferation rate resulted with the bovine collagen membrane. In conclusion, the examined parameters are very important for the development of the tissue engineering techniques and in a larger perspective also for reconstructive surgery.


Asunto(s)
Materiales Biocompatibles/farmacología , Técnicas de Cultivo de Célula/métodos , División Celular/efectos de los fármacos , Osteoblastos/citología , Fosfatasa Alcalina/metabolismo , Animales , Bovinos , Colágeno/farmacología , Colágeno/ultraestructura , Caballos , Humanos , Microscopía Electrónica de Rastreo , Osteoblastos/efectos de los fármacos
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