922 resultados para Peritoneal Cavity


Relevância:

20.00% 20.00%

Publicador:

Resumo:

In a recent study of the self-adjoint extensions of the Hamiltonian of a particle confined to a finite region of space, in which we generalized the Heisenberg uncertainty relation to a finite volume, we encountered bound states localized at the wall of the cavity. In this paper, we study this situation in detail both for a free particle and for a hydrogen atom centered in a spherical cavity. For appropriate values of the self-adjoint extension parameter, the bound states localized at the wall resonate with the standard hydrogen bound states. We also examine the accidental symmetry generated by the Runge–Lenz vector, which is explicitly broken in a spherical cavity with general Robin boundary conditions. However, for specific radii of the confining sphere, a remnant of the accidental symmetry persists. The same is true for an electron moving on the surface of a finite circular cone, bound to its tip by a 1/r1/r potential.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

One of the most important immunopathological consequence of intraperitoneal alveolar echinococcosis (AE) in the mouse is suppression of T cell-mediated immune responses. We investigated whether and how intraperitoneal macrophages (MØs) are, respectively, implicated as antigen-presenting cells (APCs). In a first step we showed that peritoneal MØs from infected mice (AE-MØs) exhibited a reduced ability to present a conventional antigen (chicken ovalbumin, C-Ova) to specific responder lymph node T cells. In a subsequent step, AE-MØs as well as naïve MØs (positive control) proved their ability to uptake and process C-Ova fluorescein isthiocyanate (FITC). Furthermore, in comparison with naïve MØs, the surface expression of Ia molecules was up-regulated on AE-MØs at the early stage of infection, suggesting that AE-MØs provide the first signal via the antigen-Ia complex. To study the accessory activity of MØs, AE-MØs obtained at the early and late stages of infection were found to decrease Con A-induced proliferation of peritoneal naïve T cells as well as of AE-sensitized peritoneal T cells, in contrast to stimulation with naïve MØs. The status of accessory molecules was assessed by analysing the expression level of costimulatory molecules on AE-MØs, with naïve MØs as controls. It was found that B7-1 (CD80) and B7-2 (CD86) expression remained unchanged, whereas CD40 was down-regulated and CD54 (= ICAM-1) was slightly up-regulated. In a leucocyte reaction of AE-MØs with naïve or AE-T cells, both types of T cells increased their proliferative response when CD28 - the ligand of B7 receptors - was exposed to anti-CD28 in cultures. Conversely to naïve MØs, pulsing of AE-MØs with agonistic anti-CD40 did not even partially restore their costimulatory activity and failed to increase naïve or AE-T cell proliferation. Neutralizing anti-B7-1, in combination with anti-B7-2, reduced naïve and AE-T cell proliferation, whereas anti-CD40 treatment of naïve MØs increased their proliferative response to Con A. These results point at the key role of B7 receptors as accessory molecules and the necessity of the integrity of CD40-expression by naïve MØs to improve their accessory activity. Taken together, the obstructed presenting-activity of AE-MØs appeared to trigger an unresponsiveness of T cells, contributing to the suppression of their clonal expansion during the chronic phase of AE-infection.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

BACKGROUND: Supraomohyoid neck dissection (SOHND) is currently performed in patients with carcinoma of the oral cavity with clinically negative neck. Most investigators consider SOHND as a staging procedure. METHODS: Records of 100 patients with cancer of the oral cavity and clinically negative neck undergoing SOHND were reviewed. The rate and significance of occult metastases are evaluated, the neck recurrences are analyzed and the indication of adjuvant radiation of pN+ necks is discussed. RESULTS: In 34 of 1814 of analyzed lymph nodes, metastatic disease was detected as follows: 30 macrometastases and 4 micrometastases. In 13 of 34 metastases (38%), extracapsular spread was observed. Twenty of 100 patients (20%) had to be upstaged. In 9 of 87 (10%) patients without local recurrence and with a minimal follow-up of 24 months, 5 ipsilateral (4 within the dissection field) and 5 contralateral neck recurrences were observed. Regional recurrence developed in 4% and 35% of patients with pN0 and pN+ necks, respectively. CONCLUSIONS: In 20% of patients with oral cavity tumors and pN0 neck, occult metastases were disclosed. Neck recurrences developed significantly more often in patients with pN+ than in those with pN0 necks. To evaluate the exact indication for an adjuvant treatment of patients with cN0/pN+ necks, prospective studies should be performed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

OBJECTIVE: Insertion of percutaneous endoscopic gastrostomies (PEG) in patients on chronic peritoneal dialysis (PD) has been reported to be contraindicated due to an increased risk of morbidity and mortality. However, no systematic survey on this topic has yet been published. DESIGN: Retrospective multicenter study. SETTING: 23 pediatric dialysis units associated with the working group Arbeitsgemeinschaft für Pädiatrische Nephrologie (APN). DATA SOURCE: A structured questionnaire on clinical details of PD patients who had undergone PEG insertion or open gastrostomy (OG) since 1994 was distributed to all pediatric dialysis units of the APN. RESULTS: 27 PD patients (20 males) from 12 centers in whom PEG insertion was performed after Tenckhoff catheter introduction were evaluated. Age at intervention ranged from 0.25 to 10.9 years (median 1.3 years). Most patients were malnourished, with standard deviation score (SDS) for body weight between -4.2 and -0.6 (median -2.2). Major complications were early peritonitis < 7 days after PEG in 10/27 (37%) patients, episodes of fungal peritonitis in 7/27 (26%) patients, 4 cessations of PD and change to hemodialysis, and 2 associated deaths. However, in 14 patients, no such problems were encountered and, in 4 patients, early peritonitis effectively treated with intraperitoneal antibiotics was the only major complication. Thus, in 18/27 (67%) patients, PD was successfully reinitiated shortly after PEG insertion. Among all participating centers, only two OG procedures were reported during the study period, illustrating a clear preference for the PEG over the OG procedure among members of the APN. CONCLUSION: PEG insertion following PD initiation carries a high risk for fungal peritonitis and potential PD failure; however, complication rates in this largest reported series were lower than previously described. Antibiotic and antifungal prophylaxis, withholding PD for 2 - 3 days, and gastrostomy placement by an experienced endoscopy team are suggested precautions for lowering the risk of associated complications. When gastrostomy placement does not occur prior to or at the time of initiating PD, the risks and benefits of percutaneous versus open placement must be carefully weighed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

OBJECTIVE: The purpose of this study was to evaluate whether pregnancy-associated plasma protein A, glycodelin, osteoprotegerin, and soluble CD163 are possible peritoneal fluid markers for endometriosis and to compare them with the established chemokine markers interleukin-8 and regulated on activation, normal T-cell expressed and secreted. STUDY DESIGN: Determination of the concentrations of interleukin-8, regulated on activation, normal T-cell expressed and secreted, pregnancy-associated plasma protein A, glycodelin, CD163, osteoprotegerin, and progesterone in the peritoneal fluid collected from women undergoing laparoscopy. RESULTS: From a total of 132 women, 77 women were diagnosed with endometriosis, and 55 women were free of the disease and served as control subjects. Pregnancy-associated plasma protein A and osteoprotegerin showed significantly (P < 0.05) elevated peritoneal fluid concentrations as a function of the severity of the disease, together with interleukin-8 and regulated on activation, normal T-cell expressed and secreted (P < .001). Glycodelin and CD163 did not differ between cases and control subjects. Many of these marker concentrations were intercorrelated strongly. CONCLUSION: Pregnancy-associated plasma protein A and osteoprotegerin may play a role in the inflammation process of endometriosis, but interleukin-8 and regulated on activation, normal T-cell expressed and secreted are superior peritoneal fluid markers.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Surgeons will increasingly have to address the development of gastrointestinal disease in transplant patients or deal with extended bowel resection and bowel anastomosis in advanced cancer patients. Immunosuppressants as well as intraoperative hyperthermic peritoneal chemoperfusion (IHPC) may alter intestinal anastomotic healing. We evaluated the effects of the immunosuppressant sirolimus and of IHPC on healing and stability of bowel anastomoses in pigs. Twenty-four pigs were divided into four groups (SIR: sirolimus was administered orally; IHPC: animals received IHPC with mitomycin-C; COMP: combination of sirolimus and IHPC was administered; CON: sham-treated control group). Animals underwent hand-sutured small bowel and left colon anastomoses and were killed on postoperative day 4. Anastomoses were evaluated by morphometric analysis and immunohistochemistry (IHC) and by measuring the bursting pressure (BP). In all experimental groups (SIR, IHPC, COMP), anastomotic BPs remained unaltered and were not statistically different compared with control (CON). In addition, ileum villous height and colonic crypt depth analysis revealed no significant difference in mucosal thickness, and IHC showed no difference among groups in proliferation, as assessed by the number of KI-67- and bromodeoxyuridine-labeled cells. Immunosuppression with sirolimus as well as IHPC with mitomycin-C do not alter healing of intestinal anastomosis in pigs.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

INTRODUCTION: This report of 2 cases describes the diagnostic procedures used to identify 2 Stafne's bone cavities (SBC) found in unusually anterior locations in the mandible, both mimicking periapical lesions of endodontic origin. METHODS: In the first patient, a 47-year-old man, an SBC was diagnosed in the area of teeth #27, 28, and 29. In the second patient, a 62-year-old man, the SBC was a fortuitous finding, because this patient was referred for dental implant therapy. RESULTS: In both cases, the final diagnosis was achieved by using limited cone beam computed tomography (CBCT) and magnetic resonance imaging (MRI). In both patients, the lingual bone cavity was found to be occupied by accessory salivary gland tissue. CONCLUSIONS: The combination of CBCT and MRI as noninvasive diagnostic techniques seems ideal to avoid surgical explorations, incisional biopsies, or enucleations of the lesion for diagnostic purposes.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

AIM: Endometriosis is often associated with lower abdominal pain, dysmenorrhea, dyspareunia, and chronic pelvic pain. There is no correlation between the extent of endometriosis and the intensity of pain. The mechanism of pain in endometriosis is unknown. The aim of our study was to investigate the influence of peritoneal fluid (PF) from endometriosis patients on cultured neural cells that are the morphological basis of nociception, and to determine whether there was a relationship between the rAFS staging and an elevation of TGF-beta1 production by these cells. METHODS: Different human neuroblastoma cell lines were grown to 3/4 confluence and then cultured in presence of PF pooled according to the presence of no, mild, or severe endometriosis. After 6 and 24 h of incubation, the morphological changes were assessed and the metabolic activity was determined. RESULTS: The different cell lines showed strongly varying proliferation and aggregation patterns. The metabolic activity was also varying between cell lines, but no consistently increased cell turnover in the PF when compared with the control medium nor associated to a particular, endometriosis-derived PF pool could be shown. In this experimental setting, we have observed that the cell proliferation in the presence of PF was inhibited, and not enhanced as it might have been expected. Measurement of TGF-beta1 showed higher production rates for this cytokine under exposure to PF than in controls for some but not all tested cell lines, but there was no association with the stage (rAFS) of the disease. CONCLUSION: The neuronal cell culture model may become a useful tool to investigate the endometriosis-derived pain, but different endpoints and cell lines may have to be introduced.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Endometriosis affects 10-20% of women during reproductive age and is a common cause of infertility and pain leading to work absenteeism and reduced quality of life.The objective of this study was to investigate the association between the presence and concentration of interleukin-8 (IL-8), RANTES, osteoprotegerin (OPG), pregnancy-associated plasma protein A (PAPP-A), tumour necrosis factor-alpha (TNF-alpha), midkine and glycodelin in the peritoneal fluid (PF) and the intensity of pain reported by patients undergoing laparoscopy in our clinic. They rated their pain during menstruation, intercourse and lower abdominal using a visual analogue scale. During laparoscopy, PF was aspirated. Pain scores were correlated to the concentration of the above substances in the PF and to the stage of endometriosis. Endometriosis was histologically confirmed in 41 of 68 participating women; 27 without such evidence were considered as controls. TNF-alpha and glycodelin correlated positively with the level of menstrual pain. For IL-8, RANTES, OPG and PAPP-A no correlation between their PF concentration and the menstrual pain scores was observed. Patients with severe dysmenorrhoea had increased PF cytokine and marker levels; the difference was significant for TNF-alpha and glycodelin when compared with the other patients (no or moderate pain). TNF-alpha and glycodelin may thus play a role in endometriosis and the severity of menstrual pain.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

To investigate the presence of epithelial neutrophil-activating peptide 78 (ENA-78) in peritoneal fluid of women with and without endometriosis and to identify the cells that produce this inflammatory protein.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Two calves were presented with a congenital mass in the rostral mandibular gingiva. In both cases the masses relapsed after surgical removal. Histologically, the two masses were composed of irregularly arranged vascular cavities, embedded in loosely arranged stroma and alcian-blue PAS positive ground substance. Radiologically, a destruction of the alveolar cavity was recognized in both cases, which was in case 1 histologically compatible with bone resorption and remodeling associated with the infiltration of abundant granulation tissue. A literature survey revealed that no consistent criteria for a correct classification for vascular tumours exists, resulting in the fact that comparable lesions were named differently in the past. We therefore propose to classify such lesions as congential vascular malformation until distinct morphological, immunohistochemical and molecular genetic analysis criteria will exist.