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1.
Cancer Imaging ; 22(1): 39, 2022 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-35962459

RESUMEN

BACKGROUND: Current radiological assessments of 18fluorodeoxyglucose-positron emission tomography (FDG-PET) imaging data in diffuse large B-cell lymphoma (DLBCL) can be time consuming, do not yield real-time information regarding disease burden and organ involvement, and hinder the use of FDG-PET to potentially limit the reliance on invasive procedures (e.g. bone marrow biopsy) for risk assessment. METHODS: Our aim is to enable real-time assessment of imaging-based risk factors at a large scale and we propose a fully automatic artificial intelligence (AI)-based tool to rapidly extract FDG-PET imaging metrics in DLBCL. On availability of a scan, in combination with clinical data, our approach generates clinically informative risk scores with minimal resource requirements. Overall, 1268 patients with previously untreated DLBCL from the phase III GOYA trial (NCT01287741) were included in the analysis (training: n = 846; hold-out: n = 422). RESULTS: Our AI-based model comprising imaging and clinical variables yielded a tangible prognostic improvement compared to clinical models without imaging metrics. We observed a risk increase for progression-free survival (PFS) with hazard ratios [HR] of 1.87 (95% CI: 1.31-2.67) vs 1.38 (95% CI: 0.98-1.96) (C-index: 0.59 vs 0.55), and a risk increase for overall survival (OS) (HR: 2.16 (95% CI: 1.37-3.40) vs 1.40 (95% CI: 0.90-2.17); C-index: 0.59 vs 0.55). The combined model defined a high-risk population with 35% and 42% increased odds of a 4-year PFS and OS event, respectively, versus the International Prognostic Index components alone. The method also identified a subpopulation with a 2-year Central Nervous System (CNS)-relapse probability of 17.1%. CONCLUSION: Our tool enables an enhanced risk stratification compared with IPI, and the results indicate that imaging can be used to improve the prediction of central nervous system relapse in DLBCL. These findings support integration of clinically informative AI-generated imaging metrics into clinical workflows to improve identification of high-risk DLBCL patients. TRIAL REGISTRATION: Registered clinicaltrials.gov number: NCT01287741.


Asunto(s)
Fluorodesoxiglucosa F18 , Linfoma de Células B Grandes Difuso , Inteligencia Artificial , Automatización , Ensayos Clínicos Fase III como Asunto , Humanos , Linfoma de Células B Grandes Difuso/diagnóstico por imagen , Linfoma de Células B Grandes Difuso/patología , Recurrencia Local de Neoplasia , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Tomografía de Emisión de Positrones/métodos , Pronóstico , Medición de Riesgo , Carga Tumoral
2.
BMC Pediatr ; 21(1): 12, 2021 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-33407279

RESUMEN

BACKGROUND: Globally, 15 million neonates are born prematurely every year, over half in low income countries (LICs). Premature and low birth weight neonates have a higher risk of intraventricular haemorrhage (IVH). There are minimal data regarding IVH in sub-Saharan Africa. This study aimed to examine the incidence, severity and timing of and modifiable risk factors for IVH amongst low-birth-weight neonates in Uganda. METHODS: This is a prospective cohort study of neonates with birthweights of ≤2000 g admitted to a neonatal unit (NU) in a regional referral hospital in eastern Uganda. Maternal data were collected from interviews and medical records. Neonates had cranial ultrasound (cUS) scans on the day of recruitment and days 3, 7 and 28 after birth. Risk factors were tabulated and are presented alongside odds ratios (ORs) and adjusted odds ratios (aORs) for IVH incidence. Outcomes included incidence, timing and severity of IVH and 28-day survival. RESULTS: Overall, 120 neonates were recruited. IVH was reported in 34.2% of neonates; 19.2% had low grade (Papile grades 1-2) and 15% had high grade (Papile grades 3-4). Almost all IVH (90.2%) occurred by day 7, including 88.9% of high grade IVH. Of those with known outcomes, 70.4% (81/115) were alive on day 28 and survival was not associated with IVH. We found that vaginal delivery, gestational age (GA) < 32 weeks and resuscitation in the NU increased the odds of IVH. Of the 6 neonates who received 2 doses of antenatal steroids, none had IVH. CONCLUSION: In this resource limited NU in eastern Uganda, more than a third of neonates born weighing ≤2000 g had an IVH and the majority of these occurred by day 7. We found that vaginal birth, earlier gestation and need for resuscitation after admission to the NU increased the risk of IVH. This study had a high rate of SGA neonates and the risk factors and relationship of these factors with IVH in this setting needs further investigation. The role of antenatal steroids in the prevention of IVH in LICs also needs urgent exploration.


Asunto(s)
Recién Nacido de Bajo Peso , Enfermedades del Prematuro , Peso al Nacer , Hemorragia Cerebral/epidemiología , Hemorragia Cerebral/etiología , Femenino , Edad Gestacional , Humanos , Lactante , Recién Nacido , Enfermedades del Prematuro/epidemiología , Enfermedades del Prematuro/etiología , Embarazo , Estudios Prospectivos , Factores de Riesgo , Uganda/epidemiología
3.
J Hosp Infect ; 102(3): 256-261, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30336168

RESUMEN

BACKGROUND: Skin antisepsis is performed before surgery to minimize the risk of surgical site infections. Chlorhexidine gluconate (CHG) is routinely used in this application, but it may be removed during surgery when prepped areas are exposed to fluid and repeated blotting. AIM: This work evaluated the effect of adding a film-forming acrylate copolymer to a CHG-containing skin preparation on minimizing CHG loss during a simulated surgical irrigation and wiping procedure. The results were compared with those obtained with a commercially available water-soluble CHG preparation. METHODS: Two studies using excised porcine skin and one study on human volunteers were performed. In each study, the CHG preparations were applied and the treated sites were challenged with repetitive saline soaks and gauze dabbing to simulate surgical conditions. Challenged and unchallenged sites were analysed either for CHG content by high-performance liquid chromatography, or for bacterial log recovery after seeding an indicator organism (reflecting remaining CHG activity). FINDINGS: After irrigation and wiping, skin treated with the film-forming CHG preparation had more CHG remaining both on excised pig skin and in the human model. In the pig model, there was a lower recovery of inoculated bacteria with the CHG preparation containing the film-forming copolymer. No skin irritation or adverse events were reported in the human study. CONCLUSIONS: The addition of a film-forming copolymer has the potential to improve the retention of CHG on skin throughout a surgical procedure compared to a water-soluble preparation. This improved retention may lead to better antimicrobial activity.


Asunto(s)
2-Propanol/administración & dosificación , Antiinfecciosos Locales/administración & dosificación , Clorhexidina/análogos & derivados , Cuidados Preoperatorios/métodos , Piel/química , Infección de la Herida Quirúrgica/prevención & control , 2-Propanol/análisis , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Antiinfecciosos Locales/análisis , Clorhexidina/administración & dosificación , Clorhexidina/análisis , Cromatografía Líquida de Alta Presión , Recuento de Colonia Microbiana , Femenino , Voluntarios Sanos , Humanos , Masculino , Viabilidad Microbiana/efectos de los fármacos , Persona de Mediana Edad , Modelos Teóricos , Estudios Prospectivos , Porcinos , Adulto Joven
4.
J Dairy Sci ; 99(12): 9942-9948, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27692720

RESUMEN

The objectives of this study were to evaluate activity, rumination time, and their association with 3 kinds of pasture flies for organic dairy cows (n=57) fed 3 grain supplementation strategies during the grazing season from May to September 2013. Cows were assigned to 1 of 3 replicate supplementation groups: (1) no corn-grain supplementation (100% pasture, PAS, n=19); (2) low corn-grain (2.72kg/cow per day, LG, n=19); and (3) high corn-grain (5.44kg/cow per day, HG, n=19). Cows calved during 2 seasons (fall and spring) at the University of Minnesota West Central Research and Outreach Center, Morris, from October to December 2012 and March to May 2013. Supplement (corn-grain and minerals) was fed in a total mixed ration of corn silage and alfalfa silage, and at least 30% of diet dry matter intake for LG and HG cows consisted of pasture. Activity and rumination time (daily and 2-h blocks of time) were monitored electronically using HR-LD tags (SCR Engineers Ltd., Netanya, Israel) for 125d. Activity (cow body movement and head movement) was reported in activity units from SCR DataFlow II software, and rumination times were reported in minutes per day. PROC HPMIXED in SAS (SAS Institute Inc., Cary, NC) was used for statistical analysis, and independent variables were season of calving (fall or spring), month of grazing (June to September), supplementation group, and interactions of month of grazing and supplementation group. Replicate was a random effect with repeated measures. Daily activity was higher for PAS cows (1,138 activity units) than for HG cows (1,001 activity units), and LG cows (1,019 activity units). Daily activity was highest in July (1,258 activity units) and lowest in September (819 activity units). Rumination was not different for PAS (397min/d), LG (384min/d), or HG (370min/d) cows. Daily rumination was greater in September (402min/d) than in July (361min/d). Daily activity increased rapidly between 0600-0800h and 1600-1800h. From 1800 to 2000h, cows had a rapid decline in activity until 0600h the next day. All supplementation groups had the greatest rumination activity from 0200 to 0400h and the least between 1000 and 1200h. Greater activity of cows on a herd basis was moderately correlated with increased fly populations. Monthly activity patterns of grazing cows were associated with fly populations on cows.


Asunto(s)
Bovinos/fisiología , Digestión , Actividad Motora , Muscidae/fisiología , Ensilaje/análisis , Zea mays/química , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Industria Lechera/métodos , Dieta/veterinaria , Suplementos Dietéticos/análisis , Grano Comestible/química , Femenino , Control de Insectos , Minnesota , Densidad de Población
5.
J Virol ; 89(17): 8783-92, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26063435

RESUMEN

UNLABELLED: Viruses exploit molecules on the target membrane as receptors for attachment and entry into host cells. Thus, receptor expression patterns can define viral tissue tropism and might to some extent predict the susceptibility of a host to a particular virus. Previously, others and we have shown that respiratory pathogens of the genus Gammacoronavirus, including chicken infectious bronchitis virus (IBV), require specific α2,3-linked sialylated glycans for attachment and entry. Here, we studied determinants of binding of enterotropic avian gammacoronaviruses, including turkey coronavirus (TCoV), guineafowl coronavirus (GfCoV), and quail coronavirus (QCoV), which are evolutionarily distant from respiratory avian coronaviruses based on the viral attachment protein spike (S1). We profiled the binding of recombinantly expressed S1 proteins of TCoV, GfCoV, and QCoV to tissues of their respective hosts. Protein histochemistry showed that the tissue binding specificity of S1 proteins of turkey, quail, and guineafowl CoVs was limited to intestinal tissues of each particular host, in accordance with the reported pathogenicity of these viruses in vivo. Glycan array analyses revealed that, in contrast to the S1 protein of IBV, S1 proteins of enteric gammacoronaviruses recognize a unique set of nonsialylated type 2 poly-N-acetyl-lactosamines. Lectin histochemistry as well as tissue binding patterns of TCoV S1 further indicated that these complex N-glycans are prominently expressed on the intestinal tract of various avian species. In conclusion, our data demonstrate not only that enteric gammacoronaviruses recognize a novel glycan receptor but also that enterotropism may be correlated with the high specificity of spike proteins for such glycans expressed in the intestines of the avian host. IMPORTANCE: Avian coronaviruses are economically important viruses for the poultry industry. While infectious bronchitis virus (IBV), a respiratory pathogen of chickens, is rather well known, other viruses of the genus Gammacoronavirus, including those causing enteric disease, are hardly studied. In turkey, guineafowl, and quail, coronaviruses have been reported to be the major causative agent of enteric diseases. Specifically, turkey coronavirus outbreaks have been reported in North America, Europe, and Australia for several decades. Recently, a gammacoronavirus was isolated from guineafowl with fulminating disease. To date, it is not clear why these avian coronaviruses are enteropathogenic, whereas other closely related avian coronaviruses like IBV cause respiratory disease. A comprehensive understanding of the tropism and pathogenicity of these viruses explained by their receptor specificity and receptor expression on tissues was therefore needed. Here, we identify a novel glycan receptor for enteric avian coronaviruses, which will further support the development of vaccines.


Asunto(s)
Infecciones por Coronavirus/veterinaria , Coronavirus del Pavo/metabolismo , Receptores Virales/metabolismo , Tropismo Viral/genética , Animales , Pollos/virología , Infecciones por Coronavirus/virología , Enteritis/virología , Galactanos/metabolismo , Virus de la Bronquitis Infecciosa/metabolismo , Intestinos/virología , Enfermedades de las Aves de Corral/virología , Unión Proteica/genética , Pavos/virología
6.
J Anim Sci ; 91(12): 5813-20, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24146155

RESUMEN

Management strategies for horses with respiratory disease include soaking hay before feeding. Hay steaming is an alternative to this practice; however, little is known about its impact on forage nutritive values or intake. The objective was to determine the effect of steaming on forage nutritive value and intake by horses. Two alfalfa (Medicago sativa L.)-orchardgrass (Dactylis glomerata L.) mixed hays were evaluated: a low moldy (NM) and moderately moldy (MM) hay. Six mature horses were used in a 10 d crossover design. Three horses were assigned to each hay type and treatments were switched on d 6. Each day, one bale of each hay was sampled (pre- and poststeaming) and steamed for 90 min using a commercial hay steamer. Two flakes of steamed or unsteamed NM or MM hay were weighed and offered simultaneously to each horse in individual hay nets. Horses were allowed access to hay for 2 h, orts were collected, and 2 h DMI was calculated. Six additional bales of NM and MM were used to evaluate the effect of steaming on total suspended particulate (TSP). Flakes of unsteamed or steamed hay were agitated in an electric cement mixer, and TSP were recorded every min for 30 min using a tapered element oscillating microbalance sampler. Paired t tests and PROC MIXED of SAS (SAS Inst. Inc., Cary, NC) were used to compare steamed and unsteamed hay nutritive values, mold concentration, TSP, and 2 h DMI. Steaming increased hay moisture and therefore reduced DM to 77 and 81% for NM and MM, respectively (P < 0.001). In NM and MM hay, steaming reduced P content by 16 and 17%, respectively (P ≤ 0.007). Steaming reduced water-soluble carbohydrates (WSC) and ethanol-soluble carbohydrates (ESC) by 13% (P = 0.001) and 27% (P = 0.003), respectively, for MM but had no effect on NM (P > 0.05). Steaming reduced mold concentrations in both hays by ≥ 91% (P < 0.001). Total suspended particulate of MM hay was reduced by 55% (P = 0.043), but TSP in NM hay was not affected by steaming (P = 0.445). Dry matter intake of NM was increased by steaming; horses ingested 0.64 kg of unsteamed and 2.02 kg of steamed hay (P < 0.001). Dry matter intake of MM was not affected by steaming (P > 0.05). For NM hay, steaming decreased P and mold concentrations and increased DMI of the hay but had no effect on TSP. In MM hay, steaming reduced P, WSC, ESC, mold concentrations, and TSP but did not affect DMI. Steaming represents a strategy for reducing TSP and mold concentrations and increasing DMI in some hays but can result in leaching of essential nutrients.


Asunto(s)
Alimentación Animal/análisis , Dactylis/química , Manipulación de Alimentos , Caballos/fisiología , Medicago sativa/química , Vapor , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Ingestión de Alimentos , Hongos , Valor Nutritivo
7.
Scand J Immunol ; 78(6): 538-44, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24111715

RESUMEN

Patients with chronic kidney disease (CKD) display a high prevalence of cardiovascular events and acute infections. Potential effector cells are the CD16(+) monocytes, known to be increased in the peripheral circulation in CKD. The aim of this study was to assess the expression of CD16 and CX3 CR1 on peripheral and in vivo extravasated monocytes in patients with CKD (GFR < 20 ml/min × 1.73 m²) using flow cytometry. In vivo extravasated monocytes were collected from a local inflammatory site, induced by a skin blistering technique. Soluble markers were assessed by Luminex. The number of CD16(+) monocytes was significantly higher in patients with CKD compared with healthy subjects, both in the peripheral circulation (P < 0.05) and at the site of induced inflammation (P < 0.001). Patients with CKD displayed significantly higher concentration of soluble CX3 CL1 both in the peripheral circulation (P < 0.01) and in the interstitial fluid (P < 0.001). In addition, patients with CKD had a significantly higher concentration of TNF-α in the peripheral circulation (P < 0.001). On the contrary, at the inflammatory site, concentrations of both TNF-α and IL-10 were significantly lower in patients with CKD compared with healthy controls (P < 0.05 for both). In conclusion, patients with CKD have an increased percentage of CD16(+) monocytes in both circulation and at the inflammatory site, and this finding is in concurrence with simultaneous changes in CX3 CR1. Together with distorted TNF-α and IL-10 levels, this may have potential impact on the altered inflammatory response in CKD.


Asunto(s)
Monocitos/inmunología , Receptores de Quimiocina/metabolismo , Receptores de IgG/inmunología , Insuficiencia Renal Crónica/inmunología , Receptor 1 de Quimiocinas CX3C , Femenino , Humanos , Inflamación/inmunología , Interleucina-10/sangre , Masculino , Persona de Mediana Edad , Receptores de Quimiocina/sangre , Receptores de IgG/sangre , Factor de Necrosis Tumoral alfa/sangre
8.
Aliment Pharmacol Ther ; 29(9): 985-91, 2009 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-19222415

RESUMEN

BACKGROUND: Levator ani syndrome is characterized by anorectal discomfort/pain, treatment of which is unsatisfactory. We hypothesized that Botulinum toxin relieves spasm and improves symptoms. AIM: To perform a randomized, placebo-controlled, crossover study to examine the efficacy and safety of botulinum toxin in patients with levator ani syndrome. METHODS: Twelve patients with levator ani syndrome (>or=1 year) received anal intra sphincteric injections of 100 units of botulinum toxin A and placebo at 90-day intervals using EMG guidance. Daily frequency, severity, duration and intensity of pain (VAS) were recorded. Anorectal manometry, balloon expulsion and pudendal nerve latency tests were performed to examine the physiological changes and adverse effects. RESULTS: Seven patients (male/female = 4/3) completed the study and three had incomplete data, but all 10 underwent in an ITT analysis; two others dropped out. After administration of botulinum toxin, the mean frequency, intensity and duration of pain were unchanged (P = 0.31) compared with baseline. The 90-day mean VAS pain score was 6.79 +/- 0.27 vs. baseline score of 7.08 +/- 0.29 (P = 0.25). Anal sphincter pressures, rectal sensory thresholds, pudendal nerve latency and balloon expulsion times were unchanged after drug or placebo administration. CONCLUSIONS: Injection of botulinum toxin into anal sphincter is safe, but it does not improve anorectal pain in levator ani syndrome.


Asunto(s)
Canal Anal/efectos de los fármacos , Toxinas Botulínicas Tipo A/administración & dosificación , Músculo Liso/efectos de los fármacos , Fármacos Neuromusculares/uso terapéutico , Espasmo/tratamiento farmacológico , Anciano , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Inyecciones Intramusculares , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Espasmo/prevención & control , Resultado del Tratamiento
9.
Science ; 309(5733): 476-81, 2005 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-16020737

RESUMEN

Neurofibrillary tangles (NFTs) are the most common intraneuronal inclusion in the brains of patients with neurodegenerative diseases and have been implicated in mediating neuronal death and cognitive deficits. Here, we found that mice expressing a repressible human tau variant developed progressive age-related NFTs, neuronal loss, and behavioral impairments. After the suppression of transgenic tau, memory function recovered, and neuron numbers stabilized, but to our surprise, NFTs continued to accumulate. Thus, NFTs are not sufficient to cause cognitive decline or neuronal death in this model of tauopathy.


Asunto(s)
Encéfalo/metabolismo , Memoria , Enfermedades Neurodegenerativas/patología , Enfermedades Neurodegenerativas/fisiopatología , Ovillos Neurofibrilares/patología , Proteínas tau/metabolismo , Envejecimiento , Animales , Atrofia , Encéfalo/patología , Cognición , Progresión de la Enfermedad , Doxiciclina/farmacología , Hipocampo/metabolismo , Hipocampo/patología , Humanos , Aprendizaje por Laberinto , Ratones , Ratones Transgénicos , Enfermedades Neurodegenerativas/metabolismo , Ovillos Neurofibrilares/metabolismo , Plasticidad Neuronal , Neuronas/metabolismo , Neuronas/patología , Tamaño de los Órganos , Fosforilación , ARN Mensajero/genética , ARN Mensajero/metabolismo , Solubilidad , Proteínas tau/química , Proteínas tau/genética
10.
Artículo en Inglés | MEDLINE | ID: mdl-15596394

RESUMEN

SDS-polyacrylamide gel electrophoresis was used to separate the secretory proteins produced by the epithelial and endometrial glands of the uterine tube and uterus in the snapping turtle Chelydra serpentina. The proteins were analyzed throughout the phases of the reproductive cycle from May to August, including preovulatory, ovulatory, postovulatory or luteal, and vitellogenic phases. The pattern of secretory proteins is quite uniform along the length of the uterine tube, and the same is true of the uterus, but the patterns for uterine tube and uterus are clearly different. We identify 13 major proteins in C. serpentina egg albumen. Bands co-migrating with 11 of these are found in the uterine tube, but at most 4 are found in the uterus, suggesting that the majority of the albumen proteins are most likely secreted in the uterine tube, not in the uterus. Although some of the egg albumen proteins are present in the uterine tube only at the time of ovulation, most of the bands corresponding to albumen proteins are present throughout the breeding season even though the snapping turtle is a monoclutch species. These results suggest that the glandular secretory phase in the uterine tube is active and quite homogeneous in function regardless of location or phase of the reproductive cycle.


Asunto(s)
Oviductos/metabolismo , Proteínas de Reptiles/metabolismo , Tortugas/metabolismo , Albúminas/metabolismo , Animales , Femenino , Membrana Mucosa/metabolismo , Útero/metabolismo
11.
Pediatr Clin North Am ; 48(5): 1307-18, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11584815

RESUMEN

Advocacy is part of the job description of a pediatrician. There is a long history of pediatrician involvement in civil society. Like other skills in pediatrics, the skills required for advocacy activities are learnable. Anyone who can learn the Krebs cycle can learn how to be a child advocate. Being a child advocate is not always easy, but it is rewarding. The 1995 Nobel Prize in Chemistry was awarded to Rowland et al for their work in the description of the destruction of stratospheric ozone by chlorofluorocarbons. Having done the groundbreaking research, Rowland and Molina spent much time working to ban chlorofluorocarbons. When asked why they, as bench scientists, ventured out of the laboratory as advocates, Rowland stated, "If not me, who? If not now, when?" (personal communication, December 7, 2000).


Asunto(s)
Defensa del Niño , Pediatría , Rol del Médico , Adulto , Niño , Salud Ambiental , Humanos
12.
J Org Chem ; 66(7): 2442-8, 2001 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-11281786

RESUMEN

The numerous biological roles of LacNAc-based oligosaccharides have led to an increased demand for these structures for biological studies. In this report, an efficient route for the synthesis of beta-galactosides using a bacterial beta-4-galactosyltransferase/-UDP-4'-gal-epimerase fusion protein is described. The lgtB gene from Neisseria meningitidis and the galE gene from Streptococcus thermophilus were fused and cloned into an expression vector pCW. The fusion protein transfers galactose to a variety of different glucose- and glucosamine-containing acceptors, and utilizes either UDP-galactose or UDP-glucose as donor substrates. A crude lysate from Escherichia coli expressing the fusion protein is demonstrated to be sufficient for the efficient preparation of galactosylated oligosaccharides from inexpensive UDP-glucose in a multigram scale. Lysates containing the fusion protein are also found to be useful in the production of more complex oligosaccharides in coupled reaction mixtures, e.g., in the preparation of sialosides from N-acetylglucosamine. Thus, bacterially expressed fusion protein is well suited for the facile and economic preparation of natural oligosaccharides and synthetic derivatives based on the lactosamine core.


Asunto(s)
Galactósidos/biosíntesis , N-Acetil-Lactosamina Sintasa/metabolismo , Proteínas Recombinantes de Fusión/metabolismo , UDPglucosa 4-Epimerasa/metabolismo , Secuencia de Carbohidratos , Escherichia coli/genética , Escherichia coli/metabolismo , Datos de Secuencia Molecular , N-Acetil-Lactosamina Sintasa/biosíntesis , N-Acetil-Lactosamina Sintasa/genética , Neisseria meningitidis/enzimología , Plásmidos/genética , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/genética , Streptococcus/enzimología , UDPglucosa 4-Epimerasa/biosíntesis , UDPglucosa 4-Epimerasa/genética , Uridina Difosfato Glucosa/metabolismo
13.
JSLS ; 5(1): 21-7, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11303991

RESUMEN

BACKGROUND AND OBJECTIVES: The most advantageous treatment for nonextensive endometriosis has long been the subject of debate. In recent years, the ability to detect atypical presentations has allowed the gynecological surgeon to treat this disease more readily. The treatment in the past has only been concerned with the singular treatment being applied at the time, not on the effects that previous treatments have had. The purpose of the current study was to see whether previous unsuccessful treatment modalities affected subsequent laser laparoscopy treatment of endometriosis. METHODS: Patients who were previously treated for their endometriosis (minimal and mild) underwent treatment of their disease by laser laparoscopy and the results were analyzed by chi2 (chi-square) analysis. RESULTS: Those patients previously treated with laser laparoscopy and laparotomy demonstrated poorer results than those previously treated with expectant, medical, or cautery. The sum of the original treatments plus the second treatment of laser laparoscopy was equal in all groups. CONCLUSIONS: If endometriosis is diagnosed at the time of laparoscopy and is easily amenable to treatment, it behooves the physician to treat it at the time of surgery.


Asunto(s)
Endometriosis/cirugía , Infertilidad Femenina/terapia , Laparoscopía/métodos , Terapia por Láser/métodos , Embarazo/estadística & datos numéricos , Adulto , Distribución de Chi-Cuadrado , Endometriosis/complicaciones , Endometriosis/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Infertilidad Femenina/etiología , Laparotomía/métodos , Reoperación , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
14.
J Biol Chem ; 276(18): 15200-7, 2001 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-11278697

RESUMEN

The sialyltransferase gene family is comprised of 16 cloned enzymes. All members contain two conserved protein domains, termed the S- and L-sialylmotifs, that participate in substrate binding. Of only six invariant amino acids, two are cysteines, with one found in each sialylmotif. Although the recombinant soluble form of ST6Gal I has six cysteines, quantitative analysis indicated the presence of only one disulfide linkage, and thiol reducing agents dithiothreitol and beta-mercaptoethanol inactivated the enzyme. Analysis of site-directed mutants showed that alanine or serine mutants of invariant Cys(181) or Cys(332) exhibit no detectable activity, either by direct assay or by staining of the transfected cells with Sambucus nigra agglutinin, which recognizes the product NeuAcalpha2,6Galbeta1,4GlcNAc on glycoproteins. In contrast, alanine mutations of charged residues adjacent to either cysteine showed little or no effect on enzyme activity. Immunofluorescence microscopy showed that although the wild type sialyltransferase is properly localized in the Golgi apparatus, the inactive cysteine mutants are retained in the endoplasmic reticulum. The results suggest that the invariant cysteine residues in the L- and S-sialylmotifs participate in the formation of an intradisulfide linkage that is essential for proper conformation and activity of ST6Gal I.


Asunto(s)
Cisteína/química , Disulfuros/química , Sialiltransferasas/química , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Células CHO , Células COS , Secuencia Conservada , Cricetinae , Cartilla de ADN , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Homología de Secuencia de Aminoácido , Sialiltransferasas/genética , Sialiltransferasas/aislamiento & purificación , Sialiltransferasas/metabolismo , Fracciones Subcelulares/enzimología , Transfección
15.
JSLS ; 4(2): 91-5, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10917113

RESUMEN

In an effort to further decrease patient postoperative scarring and discomfort, a new technique of microlaparoscopic assisted vaginal hysterectomy is employed. Using a 2-mm lateral port, a single infraumbilical port for the power source, and a 3-mm or 5-mm suprapubic port for aid in manipulation, seven consecutive patients underwent hysterectomy without complication and had rapid return to their daily activities.


Asunto(s)
Enfermedades de los Genitales Femeninos/cirugía , Histerectomía Vaginal/métodos , Laparoscopía/métodos , Microcirugia , Adulto , Anciano , Cicatriz/prevención & control , Femenino , Tecnología de Fibra Óptica , Humanos , Persona de Mediana Edad , Cicatrización de Heridas
16.
Physiol Biochem Zool ; 73(3): 290-7, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10893168

RESUMEN

We tested two hypotheses: first, that the inferior anoxia tolerance of the softshell turtle, Apalone spinifera, compared to the western painted turtle, Chrysemys picta bellii, is related to its less mineralized shell, and second, that turtle bone, like its shell, stores lactate during prolonged anoxia. Lactate concentrations of blood, hindlimb bone, and shell were measured on normoxic Apalone and Chrysemys and after anoxic submergence at 10 degrees C for 2 and 9 d, respectively. Blood and shell concentrations of Ca(2+), Mg(2+), Na(+), K(+), and inorganic phosphate (P(i); for shell only) were also measured. Because a preliminary study indicated lactate distribution in Chrysemys throughout its skeleton during anoxia at 20 degrees C, we used hindlimb bones as representative skeletal samples. Apalone shell, though a similar percentage of body mass as Chrysemys shell, had higher water content (76.9% vs. 27.9%) and only 20%-25% as much Ca(2+), Mg(2+), CO(2), and P(i). When incubated at constant pH of 6.0 or 6.5, Apalone shell powder released only 25% as much buffer per gram wet weight as Chrysemys shell. In addition, plasma [Ca(2+)] and [Mg(2+)] increased less in Apalone during anoxia at an equivalent plasma lactate concentration. Lactate concentrations increased in the shell and skeletal bone in both species. Despite less mineralization, Apalone shell took up lactate comparably to Chrysemys. In conclusion, a weaker compensatory response to lactic acidosis in Apalone correlates with lower shell mineralization and buffer release and may partially account for the poorer anoxia tolerance of this species.


Asunto(s)
Hipoxia/veterinaria , Ácido Láctico/metabolismo , Tortugas/fisiología , Acidosis Láctica/fisiopatología , Adaptación Fisiológica , Animales , Huesos/fisiología , Concentración de Iones de Hidrógeno
17.
Gynecol Oncol ; 77(3): 429-32, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10831354

RESUMEN

OBJECTIVE: A phase II study of Mifepristone (RU486) was conducted in patients with ovarian cancer whose tumors were resistant to cisplatin and paclitaxel, alone or in combination. PATIENTS AND METHODS: Forty-four patients were accrued into this study. All had ovarian cancer that had become resistant to cisplatin and paclitaxel. Patients received Mifepristone 200 mg orally on a daily basis. Patients were followed by tumor size or CA-125 levels when there was no measurable disease. A dose reduction of Mifepristone was to occur in the event of grade 3/4 hematologic, GI, or liver toxicity, creatinine >2.5%, and grade 4 peripheral neuropathy. RESULTS: Thirty-four patients were evaluable for response. Nine (26.5%) of these patients had a response to Mifepristone. Three(9%) patients had a complete response, and six (17.5%), a partial response. The response of one patient in each group was measured by CA-125 levels while the remainder had measurable disease. The response lasted 1 to 4 months in all but one patient. One patient continues to respond after more than 3 years. The major toxic effect was a rash and this was the major reason patients were removed from the study. CONCLUSION: Mifepristone has activity against ovarian cancer resistant to cisplatin and paclitaxel. The drug is well tolerated. Further studies need to be performed when this drug becomes more widely available in the United States.


Asunto(s)
Carcinoma/tratamiento farmacológico , Antagonistas de Hormonas/uso terapéutico , Mifepristona/uso terapéutico , Neoplasias Ováricas/tratamiento farmacológico , Adulto , Antineoplásicos Fitogénicos/farmacología , Biomarcadores de Tumor/análisis , Antígeno Ca-125/análisis , Carcinoma/patología , Cisplatino/farmacología , Esquema de Medicación , Resistencia a Antineoplásicos , Femenino , Antagonistas de Hormonas/administración & dosificación , Humanos , Mifepristona/administración & dosificación , Neoplasias Ováricas/patología , Paclitaxel/farmacología , Resultado del Tratamiento
18.
J Control Release ; 67(2-3): 223-32, 2000 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-10825556

RESUMEN

Based on the premise that similar surface properties between the adhesive and the substrate would yield a strong adhesive bond, copolymers of acrylic acid (AA) and 2-ethylhexyl acrylate (EHA), P(AA-co-EHA), were designed and synthesized for buccal mucoadhesion. A series of linear copolymers with varying feed ratios of the two monomers (AA and EHA) were synthesized through free radical copolymerization at 69+/-0.5 degrees C using azobis(isobutyronitrile) (AIBN) as initiator. The reactions were carried out in THF under nitrogen for 24 h. The glass transition temperatures, T(g), of the copolymers were determined using DSC. The adhesion studies were conducted to determine the effects of copolymer composition, contact time between the substrate and the adhesive, and crosshead speed on mucoadhesive performance of the copolymer films using a computer interfaced Instron material testing system. The glass transition temperature of the copolymers decreased with increasing EHA content. Wet glass surface as substrate was shown not to be a good substrate model for adhesion determination studies. The copolymer composed of 46:54 mol.% AA:EHA (an almost 1:1 ratio in the repeat units) yielded the highest mucoadhesive force in contact with porcine buccal mucosa which was significantly greater (P<0.05) than that of poly(acrylic acid) (PAA) (used as positive control). The mucoadhesive force for all copolymers studied was significantly (P<0.05) greater than that of the negative control (backing material without copolymer film) except for the EHA homopolymer. Crosshead speed increased mucoadhesive force linearly and had a more pronounced effect on the mucoadhesive performance than time of contact between the adhesive and the substrate.


Asunto(s)
Acrilatos/química , Resinas Acrílicas/química , Adhesivos/química , Mucosa Bucal , Adhesividad , Algoritmos , Animales , Rastreo Diferencial de Calorimetría , Técnicas In Vitro , Espectroscopía de Resonancia Magnética , Polímeros , Espectroscopía Infrarroja por Transformada de Fourier , Porcinos
19.
J Immunol ; 164(3): 1625-33, 2000 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-10640784

RESUMEN

Linear carbohydrate-peptide constructs based on the 13 amino acid nonnatural pan DR epitope (PADRE) and carbohydrate B cell epitopes are demonstrated to be potent immunogens. These data support our belief that PADRE should be considered as an alternative to more complex carriers for use in prophylaxis and therapeutic vaccines. Two model carbohydrate-PADRE glycoconjugates were used to demonstrate that PADRE could effectively provide T cell help for carbohydrate-specific Ab responses. Conjugates of PADRE covalently linked to the human milk oligosaccharide, lacto-N-fucopentose II or a dodecasaccharide derived from Salmonella typhimurium O-Ag induced high titer IgG Ab responses in mice, which were comparable to glycoconjugates employing human serum albumin (HSA) as the carrier protein. Different adjuvants, in combination with PADRE conjugates, allowed for the modulation of the isotype profile with alum supporting an IgG1 profile; QS-21 an IgG2a, 2b profile, while an alum/QS-21 mixture generated a balanced IgG1/IgG2b isotype profile. As defined by binding to synthetic glycoconjugates, dodecasaccharide-specific Abs exhibited fine specificity similar to protective polyclonal Ab responses previously reported for dodecasaccharide-protein conjugates. The same Abs bound to intact S. typhimurium cells, suggesting that biologically relevant specificities were produced. The affinity of the dodecasaccharide-specific Abs was further shown to be comparable to that of a well-characterized, high affinity monoclonal anti-carbohydrate Ab recognizing the same epitope.


Asunto(s)
Linfocitos B/inmunología , Epítopos de Linfocito B/inmunología , Epítopos de Linfocito T/inmunología , Glicoconjugados/inmunología , Inmunoglobulina G/biosíntesis , Vacunas contra la Malaria/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Animales , Afinidad de Anticuerpos , Especificidad de Anticuerpos , Linfocitos B/metabolismo , Secuencia de Carbohidratos , Proteínas Portadoras/inmunología , Isotipos de Inmunoglobulinas/biosíntesis , Ratones , Ratones Endogámicos C57BL , Datos de Secuencia Molecular , Oligosacáridos/inmunología , Albúmina Sérica/inmunología , Linfocitos T Colaboradores-Inductores/metabolismo
20.
J Am Assoc Gynecol Laparosc ; 6(4): 487-90, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10548710

RESUMEN

STUDY OBJECTIVE: To assess correlation between findings at standard laparoscopy and office flexible culdoscopy. DESIGN: Observational study (Canadian Task Force classification II-1). SETTING: University-affiliated hospital. PATIENTS: Eleven women undergoing diagnostic laparoscopy to evaluate infertility. INTERVENTIONS: Microlaparoscopy and flexible culdoscopy. In the first six cases laparoscopy was performed first followed by culdoscopy; in the last five cases the order was reversed. MEASUREMENTS AND MAIN RESULTS: The number of endometriotic implants or adhesions was counted for both operative techniques. The flexible 2.2-mm culdoscope provided a view of the pelvis similar to the laparoscope. Correlation between the procedures was 100%. The flexible scope achieved better visualization than the standard rigid posterior cul-de-sac culdoscope. CONCLUSION: Flexible culdoscopy is a excellent procedure for diagnostic endoscopy. It correlates well with office laparoscopy, requires less anesthesia, and is better tolerated by patients. Several operative procedures are currently being tested through this mode of access.


Asunto(s)
Culdoscopía , Infertilidad Femenina/diagnóstico , Endometriosis/complicaciones , Endometriosis/diagnóstico , Femenino , Humanos , Infertilidad Femenina/etiología , Laparoscopía , Enfermedades Peritoneales/complicaciones , Enfermedades Peritoneales/diagnóstico , Adherencias Tisulares
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