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1.
Andrologia ; 51(3): e13202, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30565706

RESUMO

Human papillomavirus (HPV) DNA has been detected in the testis tissue of 6.5% of 185 men with non-obstructive azoospermia (NOA). Others have suggested that seminal HPV originates from contamination from the genital skin and mucosa. One hundred unselected azoospermic men and 43 normal men undergoing vasectomy were recruited. Testicular biopsies for HPV examination were collected from all the men. Additionally, the normal men undergoing vasectomy delivered a semen sample and had a swab for HPV examination taken from the genital skin before vasectomy. A piece of each Vas deferens obtained during the vasectomy was examined for the presence of HPV. Two of the primarily azoospermic men were shown to have cryptozoospermia. It was not possible to detect HPV in the testis tissue of any of the included 98 azoospermic men or the 43 proven fertile men. In the proven fertile men, HPV DNA was detected in the semen of 15 men (35%), on the genital skin of 28 men (65%), and in the Vas deferens in three cases (7%). In 13 (87%) men with HPV-positive semen samples, HPV DNA was also detected in the skin swabs, and in 11 men (73%), identical HPV genotypes were found in the two locations.


Assuntos
Azoospermia/virologia , Papillomaviridae/isolamento & purificação , Pele/virologia , Ducto Deferente/virologia , Adulto , Humanos , Masculino , Espermatogênese , Vasectomia
2.
J Thorac Cardiovasc Surg ; 141(3): 732-7, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20579667

RESUMO

OBJECTIVE: Mitral ring annuloplasty is routinely applied as an adjunct procedure in reconstructive surgery on the mitral valve leaflets or chordae tendineae. It is assumed that mitral ring annuloplasty relieves tensile stress on the repaired valve tissue and thereby improves the durability of the procedure, but the indication is disputable. We sought to study the effect of mitral ring annuloplasty on the tension of the primary and secondary chordae tendineae of the anterior mitral valve leaflet in vivo. METHODS: In 17 adult pigs miniature chordal force transducers were sutured to the 2 major fixing primary chordae and the 2 strut secondary chordae of the anterior leaflet. Baseline measurements were accomplished. After randomization, one group (n = 10) underwent a mitral ring annuloplasty (Carpentier-Edwards Classic, 28 mm; Edwards Lifesciences, Irvine, Calif), and the second group (n = 7) served as controls and underwent a sham operation. Simultaneous recordings of chordae tendineae tension and hemodynamics and echocardiographic assessment of anterior leaflet occlusion area were acquired at baseline and after the mitral ring annuloplasty/sham operation. RESULTS: Mitral ring annuloplasty caused a significant reduction of the anterior leaflet occlusion area (1.85 ± 0.16 vs 4.63 ± 0.37 cm(2)) and the tension of the secondary chordae (0.33 ± 0.06 vs 0.67 ± 0.12 N) but did not affect the tension of the primary chordae (0.24 ± 0.07 vs 0.17 ± 0.06 N). The sham procedure had no effect on these variables. CONCLUSIONS: In normal porcine hearts mitral ring annuloplasty primarily relieves stress on the anterior leaflet belly rather than the leading edge. Mitral ring annuloplasty might therefore protect repairs of the central portion of the anterior leaflet and secondary chordae but not repairs that solely involve the anterior leaflet's leading edge and adjacent chordae.


Assuntos
Cordas Tendinosas/cirurgia , Implante de Prótese de Valva Cardíaca , Anuloplastia da Valva Mitral , Valva Mitral/cirurgia , Animais , Fenômenos Biomecânicos , Cordas Tendinosas/diagnóstico por imagem , Ecocardiografia Doppler em Cores , Desenho de Equipamento , Hemodinâmica , Miniaturização , Valva Mitral/diagnóstico por imagem , Estresse Mecânico , Volume Sistólico , Suínos , Transdutores de Pressão , Função Ventricular Esquerda
3.
J Heart Valve Dis ; 11(5): 736-44, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12358413

RESUMO

BACKGROUND AND AIMS OF THE STUDY: In-vivo evaluation of cavitation is based on the registration of high-frequency pressure fluctuations that represent a mixture of both cavitation and valve closing sounds, and are difficult to separate. In order to extract the cavitation signal, a high-pass filter removing the closing sound is applied. Importantly, the cut-off frequency should be chosen based on the valve's resonance pattern. This could be determined in a cavitation-free, air-operated set-up. As air and water/blood have different physical properties that could influence resonance frequencies, it is necessary to correlate the frequency content of the closing sounds recorded in air to represent expected findings in fluid. The study aim was to characterize the impact of the surrounding media on resonance frequency of a sound source, and to develop a method capable of evaluating the spectral characteristics of mechanical heart valves. METHODS: Five different valves were investigated. An in-vitro set-up was developed where the valves were operated in an airflow-controlled setting without cavitation. The valve closing sounds were recorded and a spectral analysis was performed. The resonance frequency of a simple sound source was also recorded in water and air in order to evaluate the impact of the surrounding media. RESULTS: Resonance frequencies from the sound source measured in air increased 14% compared with corresponding measurements in water. These data were used to correct findings from the five valves that showed different spectral characteristics in air. The frequency at which 97.5% of the signal energy was contained ranged from 40.9 to 65.8 kHz. CONCLUSION: Using an airflow in-vitro model, it was possible to determine the frequency signature of different mechanical heart valves. This might provide the information needed to design the optimal high-pass filter when evaluating cavitation.


Assuntos
Ruídos Cardíacos/fisiologia , Doenças das Valvas Cardíacas/fisiopatologia , Próteses Valvulares Cardíacas , Valvas Cardíacas/fisiopatologia , Espectrografia do Som , Meios de Cultura , Ecocardiografia , Filtração , Doenças das Valvas Cardíacas/diagnóstico por imagem , Doenças das Valvas Cardíacas/cirurgia , Valvas Cardíacas/diagnóstico por imagem , Humanos , Técnicas In Vitro , Modelos Cardiovasculares , Sensibilidade e Especificidade
4.
J Heart Valve Dis ; 11(3): 337-45, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12056724

RESUMO

BACKGROUND AND AIM OF THE STUDY: Chordae tendineae may be instrumental for valvular-ventricular interaction, i.e. the reciprocal exchange of force between the left ventricular myocardium and the mitral apparatus. Chordae tendineae are divided into primary leading edge chordae and secondary belly chordae, and differences in thickness and distribution may reflect different functions of the two types. Primary chordae may be fundamental for leading edge control and for correct leaflet coaptation, while secondary chordae may act as the main mediators of valvular-ventricular interaction. It was postulated that tension in secondary chordae of the anterior leaflet is greater than in the primary chordae. The study aim was to investigate the distribution of chordae tendineae tension in the porcine mitral valve in vivo. METHODS: During extracorporeal bypass, miniature chordal force transducers were implanted on four chordae in 23 Danish Landrace pigs. Chordae tendineae tension was recorded online in the open-chest condition with spontaneous circulation in three different hemodynamic conditions: baseline with no intervention; partial aortic occlusion; and during dobutamine infusion. RESULTS: Systolic tension in secondary chordae under baseline conditions was significantly higher than in primary chordae (0.7 N versus 0.2 N, respectively). No significant impact on this distribution by changing the hemodynamic condition could be identified. CONCLUSION: Chordal tension is distributed towards the secondary chordae, with a tension more than three-fold that in the primary counterpart. The magnitude of chordal tension seems to be determined primarily by ventricular pressure. This finding supports the hypothesis that secondary chordae are more important mediators of the valvular-ventricular interaction than are primary chordae.


Assuntos
Cordas Tendinosas/fisiologia , Valva Mitral/fisiologia , Contração Muscular/fisiologia , Animais , Valva Aórtica/fisiologia , Hemodinâmica/fisiologia , Modelos Animais , Músculos Papilares/fisiologia , Suínos , Função Ventricular Esquerda/fisiologia , Pressão Ventricular/fisiologia
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