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1.
Int J Cancer ; 153(7): 1406-1412, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37265033

RESUMEN

Identifying risk factors for fracture occurrence in breast cancer (BC) skeletal metastases (SM) may guide the management of such bone deposits. There is sparse evidence regarding receptor status in SM and their relationship to fracture occurrence. Our study aimed to determine the relationship between estrogen (ER), progesterone (PR) and HER2 receptor status and Ki-67 index and fracture occurrence in SM of BC. Exactly 152 samples of SM of BC obtained from individual patients were evaluated. The status of the aforementioned receptors and Ki67 index were determined in SMs samples. Their expression was compared between SM that did and did not develop a fracture. Ninety-one cases sustained a pathological fracture at the SM site, and 61 did not. Patients who sustained a pathological fracture had a higher rate of PR positivity at their SMs as compared to those with no fracture. There was no significant difference between the two groups concerning ER, HER2+ or Ki67 status. SMs secondary to BC with a fracture are more likely to be PR positive than those with no fracture. Determining the receptor status in SMs may identify high-risk groups for fracture occurrence, and determining the PR status may also guide surgical and hormonal therapy.


Asunto(s)
Neoplasias de la Mama , Fracturas Óseas , Fracturas Espontáneas , Humanos , Femenino , Neoplasias de la Mama/patología , Receptores de Progesterona/metabolismo , Receptor ErbB-2/metabolismo , Antígeno Ki-67/metabolismo , Receptores de Estrógenos/metabolismo , Estrógenos , Progesterona , Biomarcadores de Tumor/metabolismo
2.
J Strength Cond Res ; 36(6): 1532-1539, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35622104

RESUMEN

ABSTRACT: Toskic, LD, Dopsaj, MJ, Markovic, MR, Toskic, DR, Ignjatovic, AM. Mechanical and contractile properties of knee joint muscles measured by the method of tensiomyography in differently trained men and women. J Strength Cond Res 36(6): 1532-1539, 2022-The aim of this study was to investigate the differences in mechanical and contractile properties of knee joint flexor and extensor muscles between differently trained men and women, using tensiomyography (TMG). The sample consisted of 159 subjects (84 men and 75 women), who were assigned to one of 5 groups according to the following levels and types of their physical activity: physically inactive, physically active nonathletes, strength and power athletes, endurance athletes, and team sports athletes. Measurements were performed on the following knee flexor and extensor muscles of the dominant leg: rectus femoris, vastus medialis, vastus lateralis, biceps femoris, and semitendinosus. The results showed significant differences in contraction time-Tc (F = 1.911, p = 0.010) and delay time-Td (F = 1.989, p = 0.007) parameters between differently trained men and women, whereas in other TMG parameters, there were no differences between groups. It is indicated that physical activities characteristic of strength and power sports (combat sports and sprint disciplines) could lead to an increased speed of twitch force generation and fast twitch muscle fibers, and that almost any regular, systematic, and planned physical activity leads to increased muscle responsiveness. Obtained results also indicated that TMG parameters do not have enough specific discriminatory power for detecting differences between differently trained young adults.


Asunto(s)
Articulación de la Rodilla , Contracción Muscular , Electromiografía/métodos , Femenino , Humanos , Articulación de la Rodilla/fisiología , Masculino , Contracción Muscular/fisiología , Músculo Esquelético/fisiología , Músculo Cuádriceps/fisiología , Adulto Joven
3.
Gut ; 63(4): 588-97, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23604131

RESUMEN

OBJECTIVE: The incidence of inflammatory bowel disease (IBD) is increasing in Eastern Europe. The reasons for these changes remain unknown. The aim of this study was to investigate whether an East-West gradient in the incidence of IBD in Europe exists. DESIGN: A prospective, uniformly diagnosed, population based inception cohort of IBD patients in 31 centres from 14 Western and eight Eastern European countries covering a total background population of approximately 10.1 million people was created. One-third of the centres had previous experience with inception cohorts. Patients were entered into a low cost, web based epidemiological database, making participation possible regardless of socioeconomic status and prior experience. RESULTS: 1515 patients aged 15 years or older were included, of whom 535 (35%) were diagnosed with Crohn's disease (CD), 813 (54%) with ulcerative colitis (UC) and 167 (11%) with IBD unclassified (IBDU). The overall incidence rate ratios in all Western European centres were 1.9 (95% CI 1.5 to 2.4) for CD and 2.1 (95% CI 1.8 to 2.6) for UC compared with Eastern European centres. The median crude annual incidence rates per 100,000 in 2010 for CD were 6.5 (range 0-10.7) in Western European centres and 3.1 (range 0.4-11.5) in Eastern European centres, for UC 10.8 (range 2.9-31.5) and 4.1 (range 2.4-10.3), respectively, and for IBDU 1.9 (range 0-39.4) and 0 (range 0-1.2), respectively. In Western Europe, 92% of CD, 78% of UC and 74% of IBDU patients had a colonoscopy performed as the diagnostic procedure compared with 90%, 100% and 96%, respectively, in Eastern Europe. 8% of CD and 1% of UC patients in both regions underwent surgery within the first 3 months of the onset of disease. 7% of CD patients and 3% of UC patients from Western Europe received biological treatment as rescue therapy. Of all European CD patients, 20% received only 5-aminosalicylates as induction therapy. CONCLUSIONS: An East-West gradient in IBD incidence exists in Europe. Among this inception cohort--including indolent and aggressive cases--international guidelines for diagnosis and initial treatment are not being followed uniformly by physicians.


Asunto(s)
Enfermedades Inflamatorias del Intestino/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Colitis Ulcerosa/diagnóstico , Colitis Ulcerosa/epidemiología , Colitis Ulcerosa/terapia , Colonoscopía , Enfermedad de Crohn/diagnóstico , Enfermedad de Crohn/epidemiología , Enfermedad de Crohn/terapia , Europa (Continente)/epidemiología , Europa Oriental/epidemiología , Femenino , Humanos , Incidencia , Enfermedades Inflamatorias del Intestino/diagnóstico , Enfermedades Inflamatorias del Intestino/terapia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
4.
Ultrasound Obstet Gynecol ; 43(6): 662-9, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24127326

RESUMEN

OBJECTIVE: To determine associations between fetal lung and liver herniation volumes measured by magnetic resonance imaging (MRI) and mortality/need for extracorporeal membrane oxygenation (ECMO) in cases of isolated congenital diaphragmatic hernia (CDH). A secondary objective was to compare prenatal MRI parameters with two-dimensional ultrasound lung measurements. METHODS: A retrospective review of medical records of all fetuses with isolated CDH evaluated between January 2004 and July 2012 was performed. The following MRI parameters were measured at 20-32 weeks: observed/expected total fetal lung volume (o/e-TLV), predicted pulmonary volume (PPV), percentage of liver herniated into the fetal thorax (%LH) and the liver/thoracic volume ratio (LiTR). These were compared with the ultrasound-determined lung-to-head ratio (LHR) and the observed/expected LHR (o/e-LHR) in the same cohort. The predictive value of MRI and ultrasound parameters for mortality and the need for ECMO was evaluated by univariate, multivariate and factor analysis and by receiver-operating characteristics curves. RESULTS: Eighty fetuses with isolated CDH were evaluated. Overall mortality was 18/80 (22.5%). Two newborns died a few hours after birth. ECMO was performed in 29/78 (37.2%) newborns, with a survival rate of 48.3% (14/29). The side of the diaphragmatic defect was not associated with mortality (P = 0.99) or the need for ECMO (P = 0.48). Good correlation was observed among o/e-TLV, PPV, LHR and o/e-LHR as well as between %LH and LiTR (r = 0.89; P < 0.01); however, fetal lung measurements and measures of liver herniation were not correlated (all P > 0.05). All parameters were statistically associated with mortality or the need for ECMO. The best combination of measurements to predict mortality was o/e-TLV and %LH, with 83% accuracy. CONCLUSION: Mortality and the need for ECMO in neonates with isolated CDH can be best predicted using a combination of MRI o/e-TLV and %LH.


Asunto(s)
Enfermedades Fetales/patología , Hernias Diafragmáticas Congénitas/patología , Hepatopatías/patología , Pulmón/embriología , Adulto , Oxigenación por Membrana Extracorpórea , Femenino , Cabeza/embriología , Humanos , Hepatopatías/embriología , Mediciones del Volumen Pulmonar/métodos , Imagen por Resonancia Magnética , Embarazo , Curva ROC , Reproducibilidad de los Resultados , Estudios Retrospectivos , Ultrasonografía Prenatal
5.
Int J Pharm ; 662: 124479, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39019298

RESUMEN

BACKGROUND: Animal models for food allergies serve as crucial tools in understanding allergy mechanisms and assessing the efficacy of potential desensitization methods. The effectiveness of inducing allergies in mice through intragastric lavage sensitization varies. The intraperitoneal method can trigger systemic anaphylaxis, however it lacks anatomical relevance. Hence, a uniform and reliable allergy induction method in mice is required. Tape -stripping can mimic atopic dermatitis (AD), a precursor to lifelong peanut allergies in humans. Furthermore, skin damage triggers the upregulation of skin alarmins and the expansion of small-intestinal mast cells, both implicated in allergy development. METHODS: We standardized a skin-based sensitization method in a mouse model of peanut allergy using skin tape-stripping followed by allergen application. We compared this method with intragastric sensitization. RESULTS: Skin-based sensitization led to increased mast cells, goblet cells, and eosinophils in the small intestine, elevated systemic IgE levels, murine mast cell protease-1 (mMCP-1), histamine, and eosinophilic activity in peripheral blood. Moreover, it resulted in a significant hypothermic response, with nearly 30% mortality following an oral challenge one-month post-sensitization. CONCLUSION: Our research offers a standardized and readily reproducible method for inducing peanut allergy in mice, which could also be adapted for other food allergens.


Asunto(s)
Alérgenos , Quimasas , Modelos Animales de Enfermedad , Inmunoglobulina E , Mastocitos , Hipersensibilidad al Cacahuete , Piel , Animales , Hipersensibilidad al Cacahuete/inmunología , Ratones , Piel/inmunología , Piel/metabolismo , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Mastocitos/inmunología , Alérgenos/inmunología , Alérgenos/administración & dosificación , Femenino , Ratones Endogámicos BALB C , Dermatitis Atópica/inmunología , Intestino Delgado/inmunología , Intestino Delgado/metabolismo , Eosinófilos/inmunología , Histamina
6.
Front Allergy ; 5: 1278801, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38410815

RESUMEN

Introduction: The prevalence of peanut allergies is increasing, emphasizing the need for an animal model to enhance our understanding of peanut allergy pathogenesis and to advance diagnostic tools and therapeutic interventions. While mice are frequently used as model organisms, their allergic responses do not fully mirror those observed in humans, warranting the exploration of a higher animal model. The porcine gastrointestinal system closely resembles that of humans, and exhibits allergy symptoms akin to human responses, making pigs a promising model for peanut allergy research. Methods: In this study we compared two allergen sensitization protocols involving either topical allergen application after repeated tape stripping (TS) or intraperitoneal (IP) injections to induce peanut-specific allergy and anaphylaxis reactions in mini pigs. Mini pigs sensitized with a combination of peanut protein extract (PE) and cholera toxin (CT) through either the IP or the TS route. Results: Sensitized pigs via both methods developed systemic PE-specific IgG and IgE responses. Following peanut challenge via the IP route, both TS- and IP-sensitized pigs displayed allergy symptoms, including lethargy, skin rashes, vomiting, and a drop in body temperature. However, respiratory distress was observed exclusively in pigs sensitized through the TS route and not in those sensitized through the IP route. However, it is noteworthy that both groups of sensitized pigs maintained peanut hypersensitivity for up to two months post-sensitization, albeit with a reduction in the severity of allergy symptoms. Importantly, both groups exhibited sustained levels of PE-specific IgG, IgE, and elevated concentrations of mast cell protease in their blood following the IP challenges. Discussion: Overall, this study reports TS and IP as two different modes of sensitization leading to onset of peanut specific allergic reactions in mini pigs, but only the TS-sensitization led to systemic anaphylaxis (simultaneous presence of symptoms: breathing difficulty, intense skin rash, and impaired mobility). A distinctive feature of these sensitization protocols is the 100% success rate (N = 4 pigs per group) in sensitizing the subjects.

7.
Biomater Sci ; 11(17): 5859-5871, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37455612

RESUMEN

As a prospective influenza vaccination platform, a microneedle patch offers advantages such as self-administration and reduction of needle-phobia-associated vaccination avoidance. In an effort to design a broadly protective influenza vaccine we have previously developed a vaccine formulation containing the highly conserved ectodomain sequence of the M2 influenza protein (M2e) attached to the surface of gold nanoparticles (AuNPs) with CpG as a soluble adjuvant (AuNP-M2e + sCpG). Our previous studies have used the intranasal route for vaccination and demonstrated broad protection from this vaccine. Here we asked the question whether the same formulation can be effective when administered to mice using microneedles. We demonstrate that the microneedles can be coated with AuNP-M2e + sCpG formulation, and the AuNPs from the coating can be readily resuspended without aggregation. The AuNPs were delivered with high efficiency into murine skin, and the AuNPs cleared the skin within 12 h of microneedle treatment. After vaccination, strong M2e-specific humoral and cellular responses were stimulated, and the vaccinated mice were 100% protected following a lethal challenge with influenza A/PR/8/34 (H1N1).


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Vacunas contra la Influenza , Gripe Humana , Nanopartículas del Metal , Infecciones por Orthomyxoviridae , Animales , Ratones , Humanos , Gripe Humana/prevención & control , Oro , Estudios Prospectivos , Infecciones por Orthomyxoviridae/prevención & control , Ratones Endogámicos BALB C
8.
Adv Drug Deliv Rev ; 190: 114458, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35850371

RESUMEN

Subcutaneous allergen immunotherapy has been practiced clinically for decades to treat airborne allergies. Recently, the cutaneous route, which exploits the immunocompetence of the skin has received attention, which is evident from attempts to use it to treat peanut allergy. Delivery of allergens into the skin is inherently impeded by the barrier imposed by stratum corneum, the top layer of the skin. While the stratum corneum barrier must be overcome for efficient allergen delivery, excessive disruption of this layer can predispose to development of allergic inflammation. Thus, the most desirable allergen delivery approach must provide a balance between the level of skin disruption and the amount of allergen delivered. Such an approach should aim to achieve high allergen delivery efficiency across various skin types independent of age and ethnicity, and optimize variables such as safety profile, allergen dosage, treatment frequency, application time and patient compliance. The ability to precisely quantify the amount of allergen being delivered into the skin is crucial since it can allow for allergen dose optimization and can promote consistency and reproducibility in treatment response. In this work we review prominent cutaneous delivery approaches, and offer a perspective on further improvisation in cutaneous allergen-specific immunotherapy.


Asunto(s)
Desensibilización Inmunológica , Hipersensibilidad al Cacahuete , Administración Cutánea , Alérgenos , Humanos , Hipersensibilidad al Cacahuete/terapia , Reproducibilidad de los Resultados
9.
Cardiol Res Pract ; 2022: 7869356, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36471803

RESUMEN

Background/Aim: Despite technological advances in diagnosis and treatment, in-hospital mortality with acute aortic dissection type B is still about 11%. The purpose of this study was to assess the risk factors for early and long-term adverse outcomes in patients with acute aortic dissection type B treated medically or with conventional open surgery. Methods: The present study included 104 consecutive patients with acute aortic dissection type B treated in our Center from January 1st, 1998 to January 1st, 2007. Patient demographic and clinical characteristics as well as in-hospital complications were reviewed. Univariate and multivariate testing was performed to identify the predictors of in-hospital (30-day) and late (within 9 years) mortality. Results: 92 (88.5%) patients were treated medically, while 12 (11.5%) patients with complicated acute aortic dissection type B were treated by open surgical repair. In-hospital complications occurred in 35.7% patients, the most often being acute renal failure (28%), hypotension/shock (24%), mesenteric ischemia (12%), and limb ischemia (8%). The in-hospital mortality rate was 15.7% and the 9-year mortality rate was 51.9%. Independent predictors of early mortality in patients with acute aortic dissection type B were uncontrolled hypertension (HR-20.69) and a dissecting aorta diameter >4.75 cm (HR-6.30). Independent predictors of late mortality were relapsing pain (HR-7.93), uncontrolled hypertension (HR-7.25), and a pathologic difference in arterial blood pressure (>20 mmHg) (HR-5.33). Conclusion: Knowledge of key risk factors may help with a better choice of treatment and mortality reduction in acute aortic dissection type B patients.

10.
J Crohns Colitis ; 9(9): 747-53, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26055976

RESUMEN

BACKGROUND AND AIMS: The ECCO-EpiCom study investigates the differences in the incidence and therapeutic management of inflammatory bowel diseases [IBD] between Eastern and Western Europe. The aim of this study was to analyse the differences in the disease phenotype, medical therapy, surgery, and hospitalization rates in the ECCO-EpiCom 2011 inception cohort during the first year after diagnosis. METHODS: Nine Western, five Eastern European centres and one Australian centre with 258 Crohn's disease [CD], 380 ulcerative colitis [UC] and 71 IBD unclassified [IBDU] patients [female/male: 326/383; mean age at diagnosis: 40.9 years, SD: 17.3 years] participated. Patients' data were registered and entered in the web-based ECCO-EpiCom database [www.epicom-ecco.eu]. RESULTS: In CD, 36 [19%] Western Europe/Australian and 6 [9%] Eastern European patients received biological therapy [p = 0.04], but the immunosuppressive [IS] use was equal and high in these regions [Eastern Europe vs Western Europe/Australia: 53% vs 45%; p = 0.27]. Surgery was performed in 17 [24%] CD patients in Eastern Europe and 13 [7%] in Western Europe/Australia [p < 0.001, pLogRank = 0.001]. Of CD patients from Eastern Europe, 24 [34%] were hospitalized, and 39 [21%] from Western Europe/Australia, [p = 0.02, pLogRank = 0.01]. In UC, exposure to biologicals and colectomy rates were low and hospitalization rates did not differ between these regions during the 1-year follow-up period [16% vs 16%; p = 0.93]. CONCLUSIONS: During the first year after diagnosis, surgery and hospitalization rates were significantly higher in CD patients in Eastern Europe compared with Western Europe/Australia, whereas significantly more CD patients were treated with biologicals in the Western Europe/Australian centres.


Asunto(s)
Colectomía/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Inmunosupresores/uso terapéutico , Enfermedades Inflamatorias del Intestino/terapia , Pautas de la Práctica en Medicina/estadística & datos numéricos , Adulto , Anciano , Australia/epidemiología , Terapia Combinada , Bases de Datos Factuales , Europa (Continente)/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Enfermedades Inflamatorias del Intestino/diagnóstico , Enfermedades Inflamatorias del Intestino/epidemiología , Masculino , Persona de Mediana Edad , Fenotipo , Estudios Prospectivos , Adulto Joven
11.
Hypertension ; 18(6): 748-57, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1743756

RESUMEN

Membrane microviscosity, phospholipid composition, and turnover were measured in cultured vascular smooth muscle cells isolated from mesenteric arteries of stroke-prone spontaneously hypertensive and age-matched, normotensive Wistar-Kyoto rats. Membrane microviscosity, measured with fluorescence polarization, revealed greater microviscosity (lower fluidity) of the membranes isolated from smooth muscle cells from hypertensive as compared with those isolated from normotensive rats (p less than 0.01). Preincubation of membranes from hypertensive rats with 5 mM calcium reduced membrane microviscosity in "core" and in "surface" regions of the bilayer toward values observed in Wistar-Kyoto rats. Phospholipid composition did not differ between intact aortas and cultured mesenteric cells or between those tissues obtained from normotensive and from hypertensive rats. The total lipid-associated radioactivity was significantly lower in cells from stroke-prone spontaneously hypertensive rats than in those from Wistar-Kyoto controls (p less than 0.01). Phosphatidylcholine incorporated 70% and phosphatidylinositol 16% of total lipid-associated radioactivity, with no difference between cells from hypertensive and normotensive animals. Turnover of phosphatidylethanolamine was greater in cells from Wistar-Kyoto rats (p = 0.02), whereas turnover of phosphatidylserine was greater in cells from stroke-prone spontaneously hypertensive rats (p = 0.04). The greater microviscosity of the lipid bilayer in hypertension is a generalized defect of the matrix in which the transport proteins function. We hypothesize that this defect is responsible for the multiple abnormalities of membrane transport systems that have been described in genetic hypertension.


Asunto(s)
Membrana Celular/química , Hipertensión/genética , Lípidos de la Membrana/análisis , Animales , Aorta , Plaquetas/química , Calcio/farmacología , Membrana Celular/ultraestructura , Células Cultivadas , Hipertensión/patología , Lípidos de la Membrana/metabolismo , Arterias Mesentéricas , Músculo Liso Vascular/metabolismo , Ácidos Fosfatidicos/análisis , Fosfatidilcolinas/análisis , Fosfatidiletanolaminas/análisis , Fosfatidilinositoles/análisis , Fosfatidilserinas/análisis , Polarografía , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Esfingomielinas/análisis , Viscosidad/efectos de los fármacos
12.
Photosynth Res ; 68(3): 247-57, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-16228347

RESUMEN

Several methods for determination of the antenna heterogeneity of Photosystem II from fluorescence rise curves measured with DCMU have been developed so far. Using these methods, two, three or four types of Photosystem II with respect to the antenna heterogeneity were determined. However, the accuracy of some of these methods is under debate. Here, we present a new method for the determination of the antenna heterogeneity of Photosystem II. The method is based on direct simultaneous fitting of several fluorescence rise curves measured with DCMU at different intensities of light excitation. As several curves measured under different light conditions are fitted simultaneously by the same model, reliability and accuracy in determination of model parameters increase. Our method was applied to two plant materials with different structure of the thylakoid membrane: wheat leaves and cells of green alga Chlamydomonas reinhardtii.

13.
Photosynth Res ; 65(1): 29-40, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-16228468

RESUMEN

An effect of desiccation (a decrease of relative water content from 97% to 10% within 35 h) on Photosystem II was studied in barley leaf segments (Hordeum vulgare L. cv. Akcent) using chlorophyll a fluorescence and thermoluminescence (TL). The O-J-I-P fluorescence induction curve revealed a decrease of F(P) and a slight shift of the J step to a shorter time with no change in its height. The analysis of the fluorescence decline after a saturating light flash revealed an increased portion of slow exponential components with increasing desiccation. The TL bands obtained after excitation by continuous light were situated at about -27 degrees C (Z(v) band - recombination of P680(+)Q(A) (-)), -14 degrees C (A band - S(3)Q(A) (-)), +12 degrees C (B band - S(2/3)Q(B) (-)) and +45 degrees C (C band - TyrD(+)Q(A) (-)). The bands related to the S-states of oxygen evolving complex (A and B) were reduced by desiccation and shifted to higher and lower temperatures, respectively. In accordance with this, the band observed at about +27 degrees C (S(2)Q(B) (-)) after excitation by 1 flash fired at -10 degrees C and band at about +20 degrees C (S(2/3)Q(B) (-)) after 2 flashes decreased with increasing water deficit and shifted to lower temperatures. A new band around 5 degrees C appeared in both regimes of TL excitation for a relative water content of under 42% and was attributed to the Q band (S(2)Q(A) (-)). It is suggested that under desiccation, an inhibition of the formation of S(2)- and S(3)-states in OEC occurred simultaneously with a lowering of electron transport on the acceptor side of PS II. The temperature down-shift of the TL bands obtained after the flash excitation was induced at the initial phases of water stress, indicating a decrease of the activation energy for the S(2/3)Q(B) (-)recombination.

14.
Theor Appl Genet ; 104(6-7): 1078-1085, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12582615

RESUMEN

Eighty two new loci, mapped with 51 DNA clones, were added to the earlier deletion maps of the homoeologous group-6 short arms of hexaploid wheat ( Triticum aestivum L. em Thell., 2n = 6 x = 42, AABBDD). There are now 41, 56 and 52 loci mapped on deletion maps of 6AS, 6BS and 6DS, respectively. The linear order of orthologous loci in all three arms appears to be identical. The majority of the loci are located in the distal one-half of the three arms. There seems to be an increased marker/gene density from the centromeric to the telomeric regions in each arm, and the marker density in comparable physical regions is similar on all three maps. Recombination is not uniformly distributed along the chromosome arms; 60% of recombination occurs in the distal one-third of each arm. Recombination increases from the proximal region to the distal end in a nonlinear pattern. The distribution of loci and recombination along each of the three chromosome arms is highly correlated. Comparison of the 6BS deletion map from this study and a 6HS physical map of barley ( Hordeum vulgare L., 2n = 2 x = 14, HH) reveals a remarkably similar distribution of recombinogenic and gene-rich regions between the two chromosome arms, suggesting that the distribution patterns of genes may be conserved in the homoeologous group-6 chromosome short arms of wheat and barley. A consensus map of wheat group-6 short arms containing 46 orthologous loci was constructed. Comparison of the consensus map with published linkage maps of Triticeae group-6 chromosome short arms indicates that the linear order of the loci on the maps has been largely conserved. Evidence from this study does not support the existence of a 2BS-6BS reciprocal terminal translocation.

15.
Brain Res ; 907(1-2): 109-16, 2001 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-11430891

RESUMEN

The heptadecapeptide, orphanin FQ/nociceptin (OFQ/N), binds with high affinity to the ORL-1/KOR-3 opioid receptor clone, yet binds poorly with traditional opioid receptors. OFQ/N has a complex functional profile with relation to nociceptive processing, displaying pro-nociceptive properties in some studies, acting as an inhibitor of stress-induced analgesia in others, yet producing both spinal and supraspinal antinociceptive actions in other studies. Among the intracerebral sites at which OFQ/N might produce one or more of these actions is the amygdala which has been intimately implicated in both antinociceptive and stress-related responses. Therefore, the present study assessed whether microinjections into the amygdala of equimolar doses of OFQ/N(1-17) or its shorter-chained active fragments, OFQ/N(1-11) or OFQ/N(1-7), would produce analgesia as measured by either reactivity to high-intensity radiant heat or reactivity to electric shock, and produce hyperalgesia as measured by reactivity to lower-intensity radiant heat. OFQ/N(1-17) in the amygdala produced a dose-dependent and time-dependent increase in high-intensity tail-flick latencies with maximal effects observed at a dose range of 0.75-3 nmol, and lesser effects at lower (0.015-0.15 nmol) and higher (5.5-30 nmol) doses. Both OFQ/N(1-11) and OFQ/N(1-7) in the amygdala displayed lower magnitudes of analgesia than OFQ/N(1-17) on this measure, with OFQ/N(1-11) displaying maximal effects at higher (15-30 nmol) doses and OFQ/N(1-7) displaying maximal effects at lower (0.15-1.5 nmol) doses. In contrast to traditional mu and kappa opioids and beta-endorphin, none of the OFQ/N fragments in the amygdala exhibited any analgesic responses on the jump test. Finally, using a low-intensity radiant heat assay capable of detecting hyperalgesic responses, each of the OFQ/N fragments in the amygdala increased tail-flick latencies on this measure. Therefore, OFQ/N fragments appear to exert only analgesic responses in the amygdala with quantitative and qualitative differences relative to traditional opioid agonists.


Asunto(s)
Amígdala del Cerebelo/efectos de los fármacos , Analgésicos no Narcóticos/farmacología , Péptidos Opioides/farmacología , Fragmentos de Péptidos/farmacología , Amígdala del Cerebelo/fisiología , Animales , Electrochoque , Calor , Masculino , Péptidos Opioides/química , Dimensión del Dolor , Umbral del Dolor/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Tiempo de Reacción/efectos de los fármacos , Nociceptina
16.
J Theor Biol ; 191(1): 79-86, 1998 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-9593658

RESUMEN

A mathematical model of the action of a photosystem II herbicide 3-(3',4'-dichlorophenyl)-1, 1-dimenthylurea, DCMU, in plant leaves upon an external application is presented. The diffusion of DCMU in a plant tissue is described with the help of Fick's laws and the following reaction of the herbicide with the QB-binding site of photosystem II by the mass action theory. The model is used for a description of the effect of the herbicide on chlorophyll fluorescence induction (the O-J-I-P curve) measured with spring barley primary leaves submerged in the herbicide solution. The increase of the J step during the herbicide action is ascribed to an increase of the number of photosystem II centres with bound herbicide molecules and malfunctioning in the electron transport to the plastoquinone pool. The experimental data were fitted with the help of the mathematical model. Values of the diffusion coefficient and the second order rate constant of the reaction of the herbicide with photosystem II, obtained by the fitting procedure, are discussed.Copyright 1998 Academic Press Limited

17.
Naunyn Schmiedebergs Arch Pharmacol ; 352(2): 206-12, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7477445

RESUMEN

Previous reports on a series of benzoylthiophenes, including PD 81,723 [2-amino-4,5-dimethyl-3-(3-trifluoromethyl-benzoyl) thiophene], have shown specific enhancement of agonist binding at the adenosine A1 receptor. We have studied the effects of two substituted benzoylthiophenes, PD 78,416 (thieno[2,3-c]pyridine-6(5H)-carboxylic acid, 2-amino-3-benzoyl-4,7-dihydro-ethyl ester) and RS-74513-000 [2-amino-4-ethyl-5-methyl-3-(3-trifluoro-methyl-benzoyl) thiophene] on response elicited by adenosine A1 receptors in isolated guinea pig left atrium and ileum. In the electrically paced left atrium, PD 78,416 antagonized negative inotropic effect elicited by the agonist CPA [N6-cyclopentyladenosine] with a pKB value of 6.2 +/- 0.2 (n = 4). At a low concentration which had no antagonistic effect (0.1 microM), PD 78,416 enhanced the effect of CPA. The concentration-response curve to CPA was shifted leftward by 5.1 fold (95% confidence limits 2.4-11.2). In field stimulated isolated ileum, PD 78,416 (0.1, 0.3, 1 microM) did not enhance or antagonize effects of CPA. At concentrations above 1 microM, PD 78,416 decreased electrically induced contraction. This effect was not sensitive to adenosine deaminase and was not antagonized by the A1 antagonist CPX [8-cyclopentyl-1,3-dipropyl-xanthine] (1 microM). Unlike PD 78,416, RS-74513-000 (0.01, 0.1, 1, 3, 10 microM) did not antagonize or enhance effects of CPA in the left atrium. However, effects of CPA in ileum were enhanced by RS-74513-000 (1 and 3 microM).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Receptores Purinérgicos P1/efectos de los fármacos , Adenosina/análogos & derivados , Adenosina/farmacología , Inhibidores de la Adenosina Desaminasa , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacología , Animales , Estimulación Eléctrica , Cobayas , Atrios Cardíacos/efectos de los fármacos , Íleon/efectos de los fármacos , Técnicas In Vitro , Péptidos y Proteínas de Señalización Intercelular , Masculino , Contracción Muscular/efectos de los fármacos , Contracción Miocárdica/efectos de los fármacos , Péptidos , Agonistas del Receptor Purinérgico P1 , Antagonistas de Receptores Purinérgicos P1 , Piridinas/farmacología , Ribonucleósidos/farmacología , Tienopiridinas , Tiofenos/farmacología , Venenos de Avispas/farmacología
18.
Neurosurgery ; 45(3): 593-600, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10493378

RESUMEN

OBJECTIVE: After axonal injury, macrophages rapidly infiltrate and become activated in the mammalian peripheral nervous system (PNS) but not the central nervous system (CNS). We used the dorsal root pathway to study factors that modulate the response of macrophages to degenerating axons in both the PNS and the CNS. METHODS: Lewis rats underwent transection of dorsal roots (Group 1), stab within the spinal cord (Group II), crush at the dorsal root entry zone (Group III), transection of dorsal roots combined with a CNS lesion (Group IV), or systemic administration of a known activator of macrophages, lipopolysaccharide, alone (Group V) or combined with transection of dorsal roots (Group VI). ED-1 antibody stained for macrophages and activated microglia at 7, 14, and 42 days postinjury. RESULTS: At early time points, Group I demonstrated ED-1 cells in the PNS but not the CNS portion of the degenerating dorsal roots. Group II revealed ED-1 cells near the stab lesion. Group III demonstrated ED-1 cells adjacent to the dorsal root entry zone crush site. Group IV revealed ED-1 cells along both the PNS and the CNS portions of the degenerating dorsal roots when the CNS lesion was placed near the transected roots. Group V demonstrated few ED-1 cells in the PNS and the CNS, whereas Group VI revealed a marked ED-1 cellular response along both the PNS and the CNS portions of the transected dorsal roots. CONCLUSION: Local CNS trauma and systemic administration of lipopolysaccharide can "prime" macrophages/microglia, resulting in an enhanced response to degenerating axons in the CNS. Such priming might prove useful in promoting axonal regeneration.


Asunto(s)
Axones/fisiología , Macrófagos/fisiología , Microglía/fisiología , Traumatismos de la Médula Espinal/fisiopatología , Raíces Nerviosas Espinales/lesiones , Raíces Nerviosas Espinales/fisiopatología , Animales , Lateralidad Funcional , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Masculino , Microglía/efectos de los fármacos , Compresión Nerviosa , Degeneración Nerviosa , Ratas , Ratas Endogámicas Lew , Médula Espinal/anatomía & histología , Médula Espinal/fisiopatología , Heridas Punzantes/fisiopatología
19.
Neurosurgery ; 48(5): 1136-40; discussion 1140-1, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11334281

RESUMEN

OBJECTIVE: Axonal injury in the peripheral nervous system is common, and often it is associated with severe long-term personal and societal costs. The objective of this study is to use an animal model to demonstrate that transcutaneous ultrasound can accelerate recovery from an axonotmetic injury. METHODS: The sciatic nerve of adult male Lewis rats was crushed in the right midthigh to cause complete distal degeneration of axons yet maintain continuity of the nerve. Beginning 3 days after surgery, various transcutaneous ultrasound treatments or sham treatments were applied 3 days per week for 30 days to the crush site of rats that were randomly assigned to two groups. In the preliminary experiments, there were three animals in each ultrasound group and two control animals. In the final experiment, there were 22 animals in the ultrasound group and 20 animals in the control group. Recovery was assessed by use of a toe spread assay to quantify a return to normal foot function in the injured leg. Equipment included a hand-held transducer that emitted continuous-wave ultrasound. The most successful ultrasound protocol had a spatial peak, time-averaged intensity of 0.25 W/cm2 operated at 2.25 MHz for 1 minute per application. RESULTS: Rats subjected to the most successful ultrasound protocol showed a statistically significant acceleration of foot function recovery starting 14 days after injury versus 18 days for the control group. Full recovery by the ultrasound group occurred before full recovery by the control group. CONCLUSION: Transcutaneous ultrasound applied to an animal model of axonotmetic injury accelerated recovery. Future studies should focus on identification of the mechanism(s) by which ultrasound creates this effect, as a prelude to optimization of the protocol, demonstration of its safety, and its eventual application to humans.


Asunto(s)
Nervio Ciático/lesiones , Cicatrización de Heridas , Heridas no Penetrantes/fisiopatología , Heridas no Penetrantes/terapia , Animales , Masculino , Compresión Nerviosa , Ratas , Ratas Endogámicas Lew , Recuperación de la Función , Factores de Tiempo , Ultrasonografía Intervencional/instrumentación
20.
Neurosurg Clin N Am ; 12(2): 353-7, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11525213

RESUMEN

Taken together, these studies show the promise of various therapeutic modalities for the noninvasive treatment of peripheral nerve injury. Further progress on these promising methods requires determining the biologic mechanisms responsible for the ability of these modalities to enhance peripheral nerve recovery. Necessary investigations include validation or refutation of the hypothesis that these therapies act on various aspects of the natural healing process. Examples include cellular and molecular processes involved in promoting Wallerian degeneration and the rate and specificity of axonal regeneration and remyelination and muscle reinnervation, processes that are distributed between the regenerating nerve itself, the pathway of the regenerating axon, and the target of the regenerating nerve. An increased understanding of the biologic mechanisms underlying the enhancement of peripheral nerve recovery after injury would lend greater insight into the cellular and molecular mechanisms involved in successful nerve regeneration and muscle reinnervation. This increased understanding may also result in clinically beneficial treatments for peripheral nerve disorders.


Asunto(s)
Regeneración Nerviosa/fisiología , Traumatismos de los Nervios Periféricos , Terapia por Ultrasonido , Animales , Campos Electromagnéticos , Humanos , Terapia por Láser , Nervios Periféricos/patología , Nervios Periféricos/fisiopatología , Resultado del Tratamiento
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