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1.
Plant Mol Biol ; 113(6): 331-351, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38108950

RESUMEN

The opening of the stomatal pore in Zea mays is accomplished by the lateral displacement of the central canals of the dumbbell-shaped guard cells (GCs) towards their adjacent deflating subsidiary cells that retreat locally. During this process, the central canals swell, and their cell wall thickenings become thinner. The mechanical forces driving the outward displacement of the central canal are applied by the asymmetrically swollen bulbous ends of the GCs via the rigid terminal cell wall thickenings of the central canal and the polar ventral cell wall (VW) ends. During stomatal pore closure, the shrinking bulbous GC ends no longer exert the mechanical forces on the central canals, allowing them to be pushed back inwards, towards their initial position, by the now swelling subsidiary cells. During this process, the cell walls of the central canal thicken. Examination of immunolabeled specimens revealed that important cell wall matrix materials are differentially distributed across the walls of Z. mays stomatal complexes. The cell walls of the bulbous ends and of the central canal of the GCs, as well as the cell walls of the subsidiary cells were shown to be rich in methylesterified homogalacturonans (HGs) and hemicelluloses. Demethylesterified HGs were, in turn, mainly located at the terminal cell wall thickenings of the central canal, at the polar ends of the VW, at the lateral walls of the GCs and at the periclinal cell walls of the central canal. During stomatal function, a spatiotemporal change on the distribution of some of the cell wall matrix materials is observed. The participation of the above cell wall matrix polysaccharides in the well-orchestrated response of the cell wall during the reversible movements of the stomatal complexes is discussed.


Asunto(s)
Estomas de Plantas , Zea mays , Zea mays/fisiología , Estomas de Plantas/fisiología , Anisotropía , Citosol , Pared Celular
2.
Sci Total Environ ; 696: 133906, 2019 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-31442725

RESUMEN

The challenge in today's bioaerosol monitoring is to retrieve real-time information on the qualitative and quantitative composition of the ambient air in bioparticles implicated to human health. A pilot study was conducted during March-May 2018 in Athens, Greece in order to detect bioparticles within the Planetary Boundary Layer (PBL) by implementing the LIF LiDAR (Laser-Induced Fluorescence Light Detection and Ranging) technique at an excitation wavelength of 266 nm in order to determine the major components' contribution on the total fluorescence LiDAR signals aloft (30-100 m above our site). The laboratory characterization of the prevalent pollen grains and fungal spores fluorescence signatures enabled through deconvolution the breaking down of the retrieved LIF LiDAR signals and unravelled each bioparticle's contribution. The bioaerosol occurrence and concentration, as determined by the concurrent sampling with a volumetric particle sampler, verified that the detected fluorescence is related to the fungal and pollen aerosol concentration. The results of this study are very promising for the implementation of remote sensing technology in routine detection and quantification of airborne bioparticles in real-time which is important for allergy sufferers and physicians.


Asunto(s)
Aerosoles/análisis , Microbiología del Aire , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Fluorescencia , Grecia , Esporas Fúngicas
3.
Minerva Ginecol ; 67(3): 231-8, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25668420

RESUMEN

AIM: Our objectives were to evaluate the efficacy of the Perigee™ transoburator (TOT) mesh kit (American Medical Systems [AMS]-Minnetonka, MN, USA) in the treatment of ≥ stage 2 symptomatic AVP following a 2-year follow-up and to discuss the role of the pre-, peri- and postoperative measures taken to prevent complications METHODS: A total of 50 patients were eligible and were subjected to AVP surgical treatment with the use of the Perigee™ system. All patients were followed-up at 4 weeks, 2, 6, 12 and 24 months. Our primary objective was treatment success and efficacy after anatomical examination of the patient at the 24-month follow-up. Efficacy was defined as ≤ stage I AVP. All patients completed the 24-month follow-up. Our secondary objective was to examine the complication rates in relation to the use of preventative measures. RESULTS: The proportion of patients with II to III stage significantly decreased postoperatively (P<0.001). A significantly improvement was found in all POP-Q measures (P<0.05) while mean vaginal length was similar to the preoperative values. At 24-month follow-up, 45 women were defined as ≤ stage I, indicating a 90% objective success rate (95% CI: 81.4-98.6%). Two patients had vaginal mesh extrusion (4.0%) both treated with conservative measures. No erosions occurred at any point postoperatively. De novo dyspareunia was reported in two of the 17 cases (11.8%) who reported being sexually active at follow-up. One of the two had also mesh extrusion and with appliance of the vaginal estrogen and the office excision of the exposed mesh the symptoms were resolved, while the other was treated with vaginal estrogen. Two cases (4.0%) reported de novo incontinence and both were treated with a TOT sling (monarc AMS) procedure three months after the cystocele repair. Three cases (6.0%) reported pain vaginal pain postoperatively and again our treatment of choice was vaginal estrogen cream for 4 weeks with the addition of antinflammatories for 10 days and their symptoms resolved. CONCLUSIONS: The treatment of AVP with the use of Perigee™ TOT system can be both effective and safe. The goal is the improvement of the quality of life of the patients and is important to avoid or to keep as minimum as possible the complications. Main complications that the surgeon should bear in mind are the vaginal erosion, vaginal mesh extrusion, de novo dyspareunia, de novo incontinence and vaginal pain. Proper patient selection, the appliance vaginal estrogen cream pre- and postoperatively and following strict surgical principles are the mainstay of the success of the TOT operation. It is crucial for POP procedures to be performed by high-volume surgeons in this field, with extensive knowledge of the pelvic floor anatomy and the mesh's characteristics. Of course this is a small study and further clinical studies with larger number of patients are needed in order to further scientific evaluate the TOT operation.


Asunto(s)
Complicaciones Posoperatorias/prevención & control , Cabestrillo Suburetral , Mallas Quirúrgicas , Prolapso Uterino/cirugía , Administración Intravaginal , Dispareunia/epidemiología , Dispareunia/etiología , Estrógenos/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Selección de Paciente , Polipropilenos/química , Complicaciones Posoperatorias/epidemiología , Estudios Prospectivos , Calidad de Vida , Factores de Tiempo , Resultado del Tratamiento , Incontinencia Urinaria/epidemiología , Incontinencia Urinaria/etiología
4.
Case Rep Med ; 2013: 841806, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24307907

RESUMEN

Our goal is to describe our experience in the difficulties encountered during radical cystectomy for muscle invasive bladder cancer in patients with contemporary pelvic kidney. Two patients with muscle invasive bladder cancer and contemporary pelvic kidney were subjected to radical cystectomy and extended lymphadenectomy with conversion to an ileal pouch. In both cases, lymphadenectomy was the first step after entering the true pelvis. In order to proceed to the cystoprostatectomy, careful dissection of the ectopic renal vessels and proper mobilization of the kidney were performed. In both cases, an ileal pouch was our choice. The pelvic kidney is the most common sight of renal ectopia. The etiology is the aborted ascent of the fetal kidney from its initial position in the pelvis. This is the first case series describing radical cystectomy for muscle invasive urothelial carcinoma of the bladder in patients with a pelvic kidney.

5.
Plant Biol (Stuttg) ; 15(1): 203-9, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22672188

RESUMEN

Plant cell division requires the dynamic organisation of several microtubule arrays. The mechanisms of regulation of the above arrays are under rigorous research. Among several factors that are involved in plant microtubule dynamics, the Targeting Protein for Xklp2 (TPX2) has been found to play a role in spindle organisation, in combination with Aurora kinases, in dividing cells of angiosperms. Microtubule organisation in dividing cells of ferns exhibits certain peculiarities. Accordingly, the presence and distribution of a TPX2 homologue might be helpful in understanding the patterns and regulatory mechanisms of microtubule arrays in this plant group. In this study, a putative TPX2 homologue was identified using Western blotting in the fern Asplenium nidus. It was found, using immunostaining and CLSM, that it is co-localised with perinuclear preprophase microtubules and the prophase spindle, and follows the microtubule pattern during metaphase/anaphase and telophase. During cytokinesis, while in angiosperms TPX2 is degraded, in A. nidus the TPX2 signal persists, co-localising with the phragmoplast. In early post-cytokinetic cells, a TPX2 signal is present on the nuclear surface facing the daughter cell wall and, thereafter it is co-localised with the fern-specific microtubule aggregation that lines the new wall, which is possibly involved in cortical microtubule assembly.


Asunto(s)
División Celular , Helechos/metabolismo , Microtúbulos/metabolismo , Hojas de la Planta/metabolismo , Pared Celular/metabolismo , Citocinesis , Ácidos Grasos Insaturados/farmacología , Helechos/citología , Helechos/efectos de los fármacos , Hojas de la Planta/citología , Hojas de la Planta/efectos de los fármacos , Proteínas de Plantas/metabolismo , Transducción de Señal , Especificidad de la Especie
6.
Plant Biol (Stuttg) ; 12(1): 114-24, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20653894

RESUMEN

Tungsten (W) is increasingly shown to be toxic to various organisms, including plants. Apart from inactivation of molybdo-enzymes, other potential targets of W toxicity in plants, especially at the cellular level, have not yet been revealed. In the present study, the effect of W on the cortical microtubule array of interphase root tip cells was investigated, in combination with the possible antagonism of W for the pathway of molybdenum (Mo). Pisum sativum seedlings were treated with W, Mo or a combination of the two, and cortical microtubules were examined using tubulin immunofluorescnce and TEM. Treatments with anti-microtubule (oryzalin, colchicine and taxol) or anti-actomyosin (cytochalasin D, BDM or ML-7) drugs and W were also performed. W-affected cortical microtubules were low in number, short, not uniformly arranged and were resistant to anti-microtubule drugs. Cells pre-treated with oryzalin or colchicine and then treated with W displayed W-affected microtubules, while cortical microtubules pre-stabilized with taxol were resistant to W. Treatment with Mo and anti-actomyosin drugs prevented W from affecting cortical microtubules. Cortical microtubule recovery after W treatment was faster in Mo solution than in water. The results indicate that cortical microtubules of plant cells are indirectly affected by W, most probably through a mechanism depending on the in vivo antagonism of W for the Mo-binding site of Cnx1 protein.


Asunto(s)
Microtúbulos/efectos de los fármacos , Pisum sativum/efectos de los fármacos , Raíces de Plantas/efectos de los fármacos , Tungsteno/farmacología , Meristema/efectos de los fármacos , Microscopía Electrónica de Transmisión , Microscopía Fluorescente , Microtúbulos/ultraestructura , Molibdeno/farmacología , Moduladores de Tubulina/farmacología , Compuestos de Tungsteno/farmacología
7.
Transplant Proc ; 38(5): 1375-8, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16797308

RESUMEN

INTRODUCTION: Biopsy-related vascular injuries in renal transplants are rare, but they can lead to dramatic clinical symptoms prompting immediate treatment. Transcatheter embolization is a minimally invasive technique used to treat some forms of arterial bleeding. This study evaluated the efficacy of this technique in iatrogenic biopsy-related vascular lesions in renal allografts. MATERIALS AND METHODS: Over the last eight years, six patients with severe renal hemorrhage were admitted to the angiography department of our hospital for evaluation and possible further treatment. All of them had a history of previous biopsy of a transplanted kidney. They all presented with clinical signs of hemodynamic instability. Angiographic investigation of the kidneys preceded further intervention in all cases. All underwent hyperselective embolization of the specific bleeding vessel with the use of microcoils and/or gelfoam particles. RESULTS: Successful embolization of the feeding artery could be performed in all patients. Superselective segmental renal artery embolization had a successful outcome concerning a steady renal function and a stable clinical course. No complications occurred. CONCLUSION: Transcatheter embolization is a safe and efficient endovascular technique to treat biopsy-related vascular injuries in renal transplants. Immediate clinical success and significant benefit in renal function can be obtained, and the longevity of the allograft after successful embolization mainly depends on the natural outcome.


Asunto(s)
Hemorragia/epidemiología , Trasplante de Riñón/patología , Complicaciones Posoperatorias/terapia , Arteria Renal , Adolescente , Adulto , Oclusión con Balón , Biopsia , Femenino , Hematuria/etiología , Hemorragia/etiología , Humanos , Masculino
8.
Transplant Proc ; 36(5): 1398-401, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15251342

RESUMEN

BACKGROUND: Renal transplantation is an effective treatment for end-stage renal disease. Ureteral stenosis is the most frequent urologic complication. We report our long-term follow-up results concerning endourologic treatment of ureteral obstruction after renal transplantation. METHODS: Between May 1997 and September 2000, 15 patients with renal transplant obstructive uropathy were managed with percutaneous nephrostomy and prolonged ureteral stenting. RESULTS: Percutaneous nephrostomies were performed successfully in all 15 kidneys. In 13 patients, antegrade ureteral stenting was attempted, which was successful in 11 patients (85%). After prolonged ureteral stenting (mean duration 15 months), the stent was removed in all patients, 90% of whom had no recurrence. During follow-up (36 to 71 months; mean 51), urea, creatinine, sodium, and potassium determinations and ultrasound scans were performed. Success was defined as a reduction in hydronephrosis. No major complications were observed. CONCLUSIONS: Modern endourologic procedures have replaced open reconstructive surgery in most patients with ureteral obstruction after renal transplantation, because they may offer a definitive treatment with low morbidity.


Asunto(s)
Trasplante de Riñón/efectos adversos , Stents , Obstrucción Ureteral/cirugía , Cateterismo , Humanos , Complicaciones Posoperatorias/cirugía , Enfermedades Urológicas/epidemiología , Enfermedades Urológicas/etiología
9.
Onkologie ; 26(2): 147-52, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12771523

RESUMEN

BACKGROUND: As angiogenesis represents one of the hallmarks of cancer we investigated whether intravesically administered interferon-a (IFN-a2b) reduces neo-angiogenesis in the 'normal' urothelium adjacent to the tumor in patients with superficial bladder carcinoma after complete transurethral resection (TUR) of the tumor. PATIENTS AND METHODS: In the present study 47 patients after TUR of the tumor were examined. 10 patients (group A) received no further treatment (control group); 37 patients (group B) received intravesical treatment with IFN-a2b. The instillations started within 7 days after TUR, were performed weekly for 2 months, twice a month for the next 4 months, and thereafter monthly for 6 more months. Cold cup biopsies were taken before TUR of the transitional cell carcinoma (TCC): from the tumor (T), near tumor (NT) and from normal epithelium (N). Cold cup biopsies 'near tumor', were also taken during follow-up cystoscopy (C1, C2, and C3) 2, 6, and 12 months after TUR, respectively. Angiogenesis was estimated by counting the microvessels detected with CD31 immunostaining. RESULTS: Significant differences of microvascular density (MVD) between patients of group A and B appear after TUR (p < 0.005, Kruskal-Wallis and Wilcoxon test). The MVD difference was maximal 6 months after TUR (C2(A)-C2(B), second cystoscopy) and measured at 12.17 microvessels/ mm(2) (26.2%). CONCLUSION: Our results show that the intravesical administration of IFN-a2b after TUR significantly decreases the angiogenic potential of the 'healthy' urothelium adjacent to the tumor in patients with TCC. This observation could possibly explain, to a certain extent, the mechanism by which IFN-a2b reduces the recurrence rate of primary TCC.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Antineoplásicos/uso terapéutico , Carcinoma de Células Transicionales/tratamiento farmacológico , Carcinoma de Células Transicionales/cirugía , Interferón-alfa/uso terapéutico , Neovascularización Patológica/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/cirugía , Urotelio/irrigación sanguínea , Administración Intravesical , Anciano , Biopsia , Carcinoma de Células Transicionales/irrigación sanguínea , Carcinoma de Células Transicionales/patología , Quimioterapia Adyuvante , Cistoscopía , Femenino , Humanos , Interferón alfa-2 , Masculino , Microcirculación/efectos de los fármacos , Microcirculación/patología , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/prevención & control , Estadificación de Neoplasias , Neovascularización Patológica/patología , Estudios Prospectivos , Proteínas Recombinantes , Resultado del Tratamiento , Neoplasias de la Vejiga Urinaria/irrigación sanguínea , Neoplasias de la Vejiga Urinaria/patología
11.
J Urol ; 165(1): 97-9, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11125373

RESUMEN

PURPOSE: We studied the pharmacokinetics of orally administered clarithromycin in prostatic tissue to define its role in the treatment of chronic abacterial prostatitis caused by intracellular pathogens. MATERIALS AND METHODS: A total of 45 men receiving 3 oral doses of 750 mg. clarithromycin at 12-hour intervals underwent suprapubic prostatectomy for benign prostate hyperplasia 4, 5, 6 and 7 hours after the last drug dose in 13, 12, 10 and 10 patients, respectively. Concentrations were determined in the prostate tissue and in plasma by an agar diffusion assay. RESULTS: A mean peak level of clarithromycin of 3.22 and 3.08 microg./gm. of tissue was achieved 4 hours after the third drug dose at the center and periphery of the adenoma, respectively. Tissue levels remained statistically superior to plasma levels at all intervals. CONCLUSIONS: The oral administration of clarithromycin achieved a prostate level much higher than the minimal inhibitory concentration of clarithromycin for the intracellular pathogens of chronic prostatitis. Thus, clarithromycin may be considered for treating chronic abacterial prostatitis.


Asunto(s)
Antibacterianos/farmacocinética , Claritromicina/farmacocinética , Prostatitis/tratamiento farmacológico , Administración Oral , Anciano , Antibacterianos/uso terapéutico , Enfermedad Crónica , Claritromicina/uso terapéutico , Humanos , Masculino , Próstata/metabolismo , Prostatectomía , Hiperplasia Prostática/cirugía , Factores de Tiempo , Distribución Tisular
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