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1.
Hypertens Pregnancy ; 42(1): 2232029, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37417251

RESUMO

OBJECTIVE: To assess changes in expression of renal epithelial sodium channel (ENaC) and NEDD4L, a ubiquitin ligase, in urinary extracellular vesicles (UEV) of pre-eclamptic women compared to normal pregnant controls. METHODS: Urine was collected from pre-eclamptic women (PE, n = 20) or during normal pregnancy (NP, n = 20). UEV were separated by differential ultracentrifugation. NEDD4L, α-ENaC and γ-ENaC were identified by immunoblotting. RESULTS: There was no difference in the expression of NEDD4L (p = 0.17) and α-ENaC (p = 0.10). PE subjects showed increased expression of γ-ENaC by 6.9-fold compared to NP (p < 0.0001). CONCLUSION: ENaC expression is upregulated in UEV of pre-eclamptic subjects but was not associated with changes in NEDD4L.


Assuntos
Vesículas Extracelulares , Ubiquitina-Proteína Ligases Nedd4 , Pré-Eclâmpsia , Feminino , Humanos , Gravidez , Canais Epiteliais de Sódio/metabolismo , Vesículas Extracelulares/metabolismo , Rim , Pré-Eclâmpsia/metabolismo , Ubiquitina-Proteína Ligases Nedd4/genética
2.
J Appl Crystallogr ; 54(Pt 1): 80-86, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33833642

RESUMO

This article reports on energy-dispersive micro Laue (µLaue) diffraction of an individual gold nanowire that was mechanically deformed in three-point bending geometry using an atomic force microscope. The nanowire deformation was investigated by scanning the focused polychromatic X-ray beam along the nanowire and recording µLaue diffraction patterns using an energy-sensitive pnCCD detector that permits measurement of the angular positions of the Laue spots and the energies of the diffracted X-rays simultaneously. The plastic deformation of the nanowire was shown by a bending of up to 3.0 ± 0.1°, a torsion of up to 0.3 ± 0.1° and a maximum deformation depth of 80 ± 5 nm close to the position where the mechanical load was applied. In addition, extended Laue spots in the vicinity of one of the clamping points indicated the storage of geometrically necessary dislocations with a density of 7.5 × 1013 m-2. While µLaue diffraction with a non-energy-sensitive detector only gives access to the deviatoric strain, the energy sensitivity of the employed pnCCD offers absolute strain measurements with a resolution of 1%. Here, the residual strain after complete unloading of the nanowire amounted to maximum tensile and compressive strains of the order of +1.2 and -3%, which is comparable to the actual resolution limit. The combination of white-beam µLaue diffraction using an energy-sensitive pixel detector with nano-mechanical testing opens up new possibilities for the study of mechanical behavior at the nanoscale.

3.
J Appl Crystallogr ; 50(Pt 3): 901-908, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28656042

RESUMO

The full strain and stress tensor determination in a triaxially stressed single crystal using X-ray diffraction requires a series of lattice spacing measurements at different crystal orientations. This can be achieved using a tunable X-ray source. This article reports on a novel experimental procedure for single-shot full strain tensor determination using polychromatic synchrotron radiation with an energy range from 5 to 23 keV. Microbeam X-ray Laue diffraction patterns were collected from a copper micro-bending beam along the central axis (centroid of the cross section). Taking advantage of a two-dimensional energy-dispersive X-ray detector (pnCCD), the position and energy of the collected Laue spots were measured for multiple positions on the sample, allowing the measurement of variations in the local microstructure. At the same time, both the deviatoric and hydrostatic components of the elastic strain and stress tensors were calculated.

4.
Rev Sci Instrum ; 85(11): 113901, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25430118

RESUMO

µLaue diffraction with a polychromatic X-ray beam can be used to measure strain fields and crystal orientations of micro crystals. The hydrostatic strain tensor can be obtained once the energy profile of the reflections is measured. However, this remains a challenge both on the time scale and reproducibility of the beam position on the sample. In this review, we present a new approach to obtain the spatial and energy profiles of Laue spots by using a pn-junction charge-coupled device, an energy-dispersive area detector providing 3D resolution of incident X-rays. The morphology and energetic structure of various Bragg peaks from a single crystalline Cu micro-cantilever used as a test system were simultaneously acquired. The method facilitates the determination of the Laue spots' energy spectra without filtering the white X-ray beam. The synchrotron experiment was performed at the BM32 beamline of ESRF using polychromatic X-rays in the energy range between 5 and 25 keV and a beam size of 0.5 µm × 0.5 µm. The feasibility test on the well known system demonstrates the capabilities of the approach and introduces the "3D detector method" as a promising tool for material investigations to separate bending and strain for technical materials.

5.
J Med Liban ; 47(6): 360-3, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10758711

RESUMO

Mirizzi syndrome is a rare pathology of the extrahepatic biliary system caused by a large gallbladder calculous either compressing or eroding into the collecting biliary tree. This paper describes a case of Mirizzi syndrome with atypical presentation. A review of the literature including diagnostic and therapeutic modalities are reported.


Assuntos
Fístula Biliar/diagnóstico , Colecistite/diagnóstico , Colestase Extra-Hepática/diagnóstico , Cálculos Biliares/diagnóstico , Idoso , Fístula Biliar/patologia , Fístula Biliar/cirurgia , Colecistite/patologia , Colecistite/cirurgia , Colestase Extra-Hepática/patologia , Colestase Extra-Hepática/cirurgia , Doença Crônica , Vesícula Biliar/patologia , Cálculos Biliares/patologia , Cálculos Biliares/cirurgia , Humanos , Masculino , Síndrome
6.
Artigo em Francês | MEDLINE | ID: mdl-7569195

RESUMO

PURPOSE OF THE STUDY: This survey of 48 cases of trochanteric non-union in THR showed that this complication had not only functional consequences (one patient out of three complains of some instability and mild pain) but may also lead to stem loosening (3/48) through an original mechanism. The movements of the trochanter produce wear debris, mainly from the broken metal wires fixing the trochanter (and from rubbing of the cement on the femoral side of the osteotomy). These debris create an osteolytic granuloma between the proximal lateral endocortex and the cement, which extends progressively to the distal tip of the stem. MATERIAL AND METHODS: A continuous series of 446 cemented Charnley type prostheses by the trans trochanteric approach showed 48 trochanteric non unions (11 per cent) which were examined at an average follow up of 6.5 years. Six patients were reoperated for important hip instability. Ten who suffered only from moderate instability were not reoperated on. 32 were asymptomatic and therefore where not reoperated, but 3 of them suffered from severe femoral loosening after 6 years and required revision. RESULTS: These cases of loosening due to trochanteric non union were characterized by: clinical patterns: they occurred only after 6 years, in active patients under 50; radiological aspects: osteolysis was initially limited to the lateral cortex (without any calcar resorption or radio lucency around the cup) analysis by electronic microscopy of the granuloma (harvested at revision) showed metallic debris (under 1 mu) inside macrophages, with some cement particles (secondary to the loosening). DISCUSSION: Mechanism of loosening These cases of loosening differ from those due to granuloma caused by wear debris of PE and from granulomas resulting from deterioration of the cement around the femoral stem, which both occur only much later with the Charnley prostheses. In our consecutive series of 32 cases of Charnley THR in young active patients with an average follow up of 9.5 years, the only cases of femoral loosening observed were related to trochanteric non unions. Hyposolicitation by trochanteric non union does not lead either to bone resorption or to stem loosening, as we could notice in a series of moderately active patients over 60 with loose non unions. Loosening due to trochanteric non unions was only observed in active patients with tight non unions, as the patient's activity and contact of the surfaces increase rubbing and wear of metal wires. Prevention of trochanteric non union. Despite attentive care to fixation of trochanter there is an unavoidable percentage of non union even in simple cases (3 to 4 per cent according to Charnley). Therefore we advocate this technique only when a large exposition is necessary (revisions, THR for dislocation etc..) CONCLUSIONS: Trochanteric non union may lead to stem loosening after 6 years in active patients under 50. Therefore we recommend: to restrict the use of the trochanteric approach to some difficult THR: revisions, prostheses for dislocation, etc... to reoperate patients under 50 with a trochanteric non union: if it is clinically symptomatic if a progressive granuloma of the lateral cortex, even though asymptomatic, appears.


Assuntos
Fêmur/cirurgia , Fraturas do Quadril/cirurgia , Prótese de Quadril/efeitos adversos , Osteotomia/métodos , Falha de Prótese , Pseudoartrose/etiologia , Adulto , Feminino , Fêmur/diagnóstico por imagem , Seguimentos , Fraturas do Quadril/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Osteotomia/efeitos adversos , Pseudoartrose/diagnóstico por imagem , Radiografia , Reoperação
7.
Zentralbl Pathol ; 137(2): 157-63, 1991.
Artigo em Alemão | MEDLINE | ID: mdl-1911731

RESUMO

Reported in this paper is the case of a boy aged 15 years with sellar germinoma which led to one singular pulmonary metastasis, three years after subtotal surgical removal and subsequent successful irradiation of the tumor rest. The primary tumor together with the lung metastasis were characterised as germinoma with trophoblastic giant cells as additional elements. Interpretation of the pulmonary tumour was somewhat difficult, since diagnosis of the primary tumor had encouraged assumption of a chromophobic hypophyseal adenoma with polymorphic manifestation, with no relationship between the intracranial and pulmonary tumors being presumed by the surgeon. The true nature of the metastasis and, consequently, the histogenetic identity of both tumors was cleared up by immunohistochemical detection of beta-HCG in almost all syncytiotrophoblasts. Comprehensive analysis of the literature on metastasising intracranial germinomas may be helpful in disclosing possible relationships between the histological type of a primary tumor or neurosurgical action and the metastatic potential of tumors.


Assuntos
Neoplasias Encefálicas/patologia , Disgerminoma/patologia , Neoplasias Pulmonares/secundário , Adolescente , Disgerminoma/secundário , Humanos , Neoplasias Pulmonares/patologia , Masculino , Sela Túrcica
8.
Zentralbl Allg Pathol ; 135(8): 751-6, 1989.
Artigo em Alemão | MEDLINE | ID: mdl-2618194

RESUMO

Reported in this paper is a predominantly mucous differentiated acinic cell adenocarcinoma of seromucous tracheal glands in a male patient aged 64 years. Local surgical treatment was performed several times within one year and was always followed by recurrence. The naked eye inspection showed a partial polypous appearance of the tumor. Histologically the carcinoma is composed of lobular arranged solid and cribrous cell formations only separated by a sparse fibrous stroma. The tumor is not capsulated, and invasive growth is evident. Large cells with abundant bright cytoplasm and a strongly positive reaction to PAS form the main constituent of the tumor. Signet cell formation sometimes occurs. Electron microscopic examination reveals abundant secretory granules. These cells are in full accordance with mucous cellular elements of adjacent seromucous tracheal glands from which this rare tumor has obviously originated.


Assuntos
Carcinoma/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias da Traqueia/patologia , Carcinoma/ultraestrutura , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/ultraestrutura , Neoplasias da Traqueia/ultraestrutura
9.
Ann Med Interne (Paris) ; 139(1): 12-4, 1988.
Artigo em Francês | MEDLINE | ID: mdl-2834987

RESUMO

The authors report 5 new cases (3 women, 2 men) of granular cell tumours of the oesophagus. Two patients were treated by endoscopic resection with a diathermy loop, two patients underwent surgical ablation and the other tumour was discovered at autopsy. There were no complications related to treatment and there have been no recurrences to date. Endoscopic resection of these tumours would seem to be the treatment of choice when their size is less than 30 mm.


Assuntos
Neoplasias Esofágicas/diagnóstico , Neoplasias de Tecido Muscular/diagnóstico , Adulto , Esofagoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Am J Physiol ; 253(1 Pt 2): H1-7, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3605354

RESUMO

We measured the effect of vasopressin (8 mU X kg-1 X min-1) on reflex inhibition of renal sympathetic nerve activity induced by volume expansion in 13 sinoaortic-denervated anesthetized rabbits. Volume expansion increased left ventricular end-diastolic pressure (LVEDP) from 5.1 +/- 0.7 to 14.1 +/- 1.4 mmHg and decreased renal nerve activity (RNA) from 57.4 +/- 6.9 to 30.2 +/- 5.6 impulses/s. Infusion of vasopressin elevated LVEDP from 6.0 +/- 1.0 to 7.3 +/- 1.1 mmHg and decreased RNA from 61.8 +/- 7.2 to 47.1 +/- 6.3 impulses/s. Heart rate fell from 243 +/- 7 to 231 +/- 9 beats/min; no other significant hemodynamic changes were seen. During the infusion of vasopressin, volume expansion increased LVEDP to 13.7 +/- 1.2 mmHg and decreased RNA to 17.0 +/- 4.2 impulses/s. The slopes relating the percent decrease in RNA to the rise in LVEDP were calculated from values of RNA recorded at several levels of LVEDP. The slope averaged -6.2 +/- 1.1%/mmHg before vasopressin and nearly doubled (-11.9 +/- 1.8%/mmHg) during vasopressin. Infusion of placebo (saline) instead of vasopressin did not alter the reflex inhibition of nerve activity. Bilateral vagotomy abolished the decrease in resting nerve activity that occurred during infusion of vasopressin as well as the reflex inhibition of RNA. These data demonstrate that vasopressin facilitates the reflex inhibition of renal sympathetic nerve activity associated with increases in LVEDP and mediated through vagal afferents.


Assuntos
Rim/inervação , Inibição Neural , Neurônios Aferentes/fisiologia , Nervo Vago/fisiologia , Vasopressinas/fisiologia , Animais , Feminino , Masculino , Veículos Farmacêuticos/farmacologia , Substitutos do Plasma/farmacologia , Coelhos , Descanso , Sistema Nervoso Simpático/fisiologia , Vagotomia , Vasopressinas/farmacologia
11.
Surgery ; 95(5): 562-6, 1984 May.
Artigo em Inglês | MEDLINE | ID: mdl-6710353

RESUMO

Forty women were investigated 6 to 24 months after radical mastectomy for the presence of functioning lymphovenous communications in the arm; 20 cases were edematous and the rest were not. Ten normal volunteer women were also investigated and served as controls. Iodinated (I125) human serum albumin was injected intralymphatically in the arm, and samples of blood were taken from both basilic veins simultaneously at 5, 10, 15, 30, 45, and 60 minutes. The radioactivity of each sample was determined with a scintillation counter. Lymphangiography was performed in all cases 1 month after the isotopic studies and lymphangiograms were evaluated for the presence of lymphovenous shunts. In the volunteers and the edematous postmastectomy group, there was negligible lymphovenous shunting of labeled albumin. In the nonedematous postmastectomy group, there was an increased quantity of local lymphovenous transfer of iodinated albumin. Lymphovenous shunts were detected radiologically in two patients who did not have edema. On the basis of our observations, the incidence of postmastectomy lymphedema is predetermined and is a consequence of the lack of existence of lymphovenous communications that can allow adequate lymph flow drainage from the arm after radical dissection of axillary lymph nodes.


Assuntos
Linfedema/etiologia , Mastectomia/efeitos adversos , Braço/irrigação sanguínea , Feminino , Humanos , Sistema Linfático/anatomia & histologia , Linfografia , Soroalbumina Radioiodada
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