Scaled physical models can be useful in analyzing stage-specific hemodynamics in the embryonic human heart to address correlations between early physical stressors and myocardial wall responses. We generated models of the cardiac blood space from reconstructions of four digitized human embryo images from Carnegie Collection at the Armed Forces Institute of Pathology. From physical scale models manufactured by stereolithography, compliant sleeves can be created for flow dynamics studies. This novel use of Carnegie collection images and graphical modeling software provides tools for broadening our understanding of normal and aberrant heart formation.

Embryonic and Fetal Development↗

PubMedDate not supplied

[Familial adenomatosis coli--a precancerous condition].

The presented paper includes the medical records of five children with familial adenomatous polyposis coli on the one hand and the detailed description of the pathologic findings of the disease on the other hand. Particular emphasis is given to the morphologic criteria of the disorder predisposing the affected individuals to development of colorectal cancer at unusually early ages. In the current cases there was a so-called classical presentation of diffuse polyposis in the early and late childhood respectively. The diagnosis was established in supposedly unaffected siblings due to colonoscopy and radiologic procedures. Prophylactic total colectomy was performed in all proven cases. The association with extracolonic tumours has proved to be a remarkable feature of the disease. This fact is especially stressed.

Adenoma↗

PubMedDate not supplied

[Pre- and retrorenal neuroblastoma without kidney displacement].

Pre- and retrorenal growing neuroblastomas did not produce any displacement of the kidney or any obstruction in the intravenous pyelogram. The diagnosis was done by ultrasound-scanning as well as biochemically before surgery. The reported cases show that sonography and determination of the catecholamine metabolites are essential in the diagnostic evaluation of abdominal tumors in childhood.

Abdominal Neoplasms↗

PubMedDate not supplied

Artificial abdominal hernia for the treatment of hepatomegaly in a neonate with stage 4S neuroblastoma.

Surgical widening of the abdomen by a silastic pouch has been used very rarely in the management of critically ill infants with hepatomegaly due to neuroblastoma stage 4S. A female newborn baby was referred on the second day of life because of local compressive effects of a massive hepatomegaly, which lead to multiorgan failure. An artificial abdominal hernia was created on the third day of life using a silastic pouch. During the operation oxygenation and ventilation improved and urinary output returned. After chemotherapeutic reduction of hepatic metastases and primary tumor the pouch was successfully removed on day 57 without local complications. The child has survived for more than 1 year and is in complete remission. An artificial abdominal hernia should be considered more often in the critically ill neonate with stage 4S neuroblastoma and massive hepatomegaly.

Decompression↗

PubMedDate not supplied

A physical model describing the mechanism for formation of gas microbubbles in patients with mitral mechanical heart valves.

This study was aimed at developing a physical model, supported by experimental observations, to describe the formation and growth of microbubbles seen in patients with mitral mechanical heart valves (MHV). This phenomenon, often referred to as high intensity transient signals (HITS), appears as bright, intense, high-velocity and persistent echoes detected by Doppler ultrasonography at the instant of closure. The long-term clinical implications of HITS has yet to be determined. However, there are reports of a certain degree of neurological disorder in patients with mitral MHV. The numerical analysis has shown the existence of a twofold process (1) nucleation and (2) microbubble growth as a result of cavitation. While mild growth of nuclei is governed by diffusion, explosive growth of microbubbles is controlled by pressure drop on the atrial side of mitral MHV. It was demonstrated that there exist limits on both microbubble size and regurgitant velocity, above which microbubbles grow explosively, and below which growth is almost nonexistent. Therefore, prevention of excessive pressure drops induced by high closing velocities related to the dynamics of closure of mitral MHV may offer design changes in the future generations of mechanical valves.

Blood Pressure↗