Repair of mitral valve and subaortic mycotic aneurysm in a child with endocarditis

Endocarditis requiring surgical intervention in children is uncommon. Individualized operative therapy must be fashioned to the particular pathology of each case. In this case we describe mitral anterior leaflet homograft patch augmentation valvuloplasty, subaortic homograft patch closure of a large mycotic aneurysm, and homograft aortic root replacement in a 3-year-old patient with endocarditis after remote repair of complete atrioventricular canal.     

Diagnostic and prognostic significance of biochemical indicators in colorectal neoplasms

Activities of some enzymes and content of medium-weight molecules in patients with colorectal cancer were studied in order to assess the diagnostic value of these parameters for detection of tumors in the large intestine and development of endogenous intoxication after surgery and for prediction of remote results of treatment. Increased activities of creatine phosphokinase and hexokinase is typical of tumor growth, whereas increased activities of alkaline phosphatase and gamma-glutamyl transpeptidase are observed only in metastases to the liver. The role of medium-weight molecules in the diagnosis of endogenous intoxication during the early postoperative period is shown. The content of these molecules in the sera increases 3 days before clinical manifestation of endotoxicosis, when the traditional parameters are virtually normal.     

A 340 kDa hyaluronic acid secreted by human vascular smooth muscle cells regulates their proliferation and migration

The formation of atherosclerotic lesions is characterized by invasion of vascular smooth muscle cells (VSMC) into the tunica intima of the arterial wall and subsequently by increased proliferation of VSMC, a process apparently restricted to the intimal layer of blood vessels. Both events are preceded by the pathological overexpression of several growth factors, such as platelet-derived growth factor (PDGF) which is a potent mitogen for VSMC and can induce their chemotaxis. PDGF is generally not expressed in the normal artery but it is upregulated in atherosclerotic lesions. We have previously shown that PDGF-BB specifically stimulates proliferating VSMC to secrete a 340 kDa hyaluronic acid (HA-340). Here, we present evidence regarding the biological functions of this glycan. We observed that HA-340 inhibited the PDGF-induced proliferation of human VSMC in a dose-dependent manner and enhanced the PDGF-dependent invasion of VSMC through a basement membrane barrier. These effects were abolished following treatment of HA-340 with hyaluronidase. The effect of HA-340 on the PDGF-dependent invasion of VSMC coincided with increased secretion of the 72-kDa type IV collagenase by VSMC and was completely blocked by GM6001, a hydroxamic acid inhibitor of matrix metalloproteinases. HA-340 did not exert any chemotactic potency, nor did it affect chemotaxis of VSMC along a PDGF gradient. In human atheromatic aortas, we found that HA-340 is expressed with a negative concentration gradient from the tunica media to the tunica intima and the atheromatic plaque. Our findings suggest that HA-340 may be linked to the pathogenesis of atherosclerosis, by modulating VSMC proliferation and invasion.     

Modulation of glomerular hypertension defines susceptibility to progressive glomerular injury

The fawn-hooded rat constitutes a spontaneous model for chronic renal failure with early systemic and glomerular hypertension, proteinuria (UpV) and high susceptibility to development of focal and segmental glomerular sclerosis (FGS). It has been argued that uninephrectomy (UNX) accelerates the development of glomerular injury by aggravation of glomerular hypertension and by an independent effect to promote glomerular enlargement. The present study was performed to further delineate the importance of these parameters for the development of FGS. At the age of eight weeks male rats were UNX and randomly assigned to either control (CON), enalapril (ENA) or Nw-nitro L-arginine methyl ester (NAME) treatment. In all groups glomerular hemodynamic studies were performed four weeks post-UNX. Systemic blood pressure and UpV were monitored for 4 to 12 weeks post-UNX. Kidneys were then prepared for morphologic study. ENA treatment achieved control of both systemic and glomerular hypertension, maintenance of glomerular hyperfiltration and hyperperfusion, increased ultrafiltration coefficient(Kf), and long-term protection against UpV and FGS. NAME rats showed aggravation of both systemic and glomerular hypertension, decreased renal perfusion and filtration with reduced Kf, and high filtration fraction. The incidence of FGS in NAME and CON groups was similar at 8 and 12 weeks post-UNX, respectively. Glomerular enlargement was present in CON and ENA rats, but did not correlate with injury, while glomerular tuft size was lowest in NAME rats, which displayed prominent glomerular injury. Systemic blood pressure correlated strongly with glomerular capillary pressure. We conclude that systemic and glomerular hypertension govern the development of UpV and FGS.(ABSTRACT TRUNCATED AT 250 WORDS)     

An estimate by two methods of thyroid absorbed doses due to BRAVO fallout in several Northern Marshall Islands

Estimates of the thyroid absorbed doses due to fallout originating from the 1 March 1954 BRAVO thermonuclear test on Bikini Atoll have been made for several inhabited locations in the Northern Marshall Islands. Rongelap, Utirik, Rongerik and Ailinginae Atolls were also inhabited on 1 March 1954, where retrospective thyroid absorbed doses have previously been reconstructed. The current estimates are based primarily on external exposure data, which were recorded shortly after each nuclear test in the Castle Series, and secondarily on soil concentrations of 137Cs in samples collected in 1978 and 1988, along with aerial monitoring done in 1978. The external exposures and 137Cs soil concentrations were representative of the atmospheric transport and deposition patterns of the entire Castle Series tests and show that the BRAVO test was the major contributor to fallout exposure during the Castle series and other test series which were carried out in the Marshall Islands. These data have been used as surrogates for fission product radioiodines and telluriums in order to estimate the range of thyroid absorbed doses that may have occurred throughout the Marshall Islands. Dosimetry based on these two sets of estimates agreed within a factor of 4 at the locations where BRAVO was the dominant contributor to the total exposure and deposition. Both methods indicate that thyroid absorbed doses in the range of 1 Gy (100 rad) may have been incurred in some of the northern locations, whereas the doses at southern locations did not significantly exceed levels comparable to those from worldwide fallout. The results of these estimates indicate that a systematic medical survey for thyroid disease should be conducted, and that a more definitive dose reconstruction should be made for all the populated atolls and islands in the Northern Marshall Islands beyond Rongelap, Utirik, Rongerik and Ailinginae, which were significantly contaminated by BRAVO fallout.     

Diagnosis and treatment of pustular disorders in the neonate

The analytical result of a laboratory examination is a scientific fact and has no medical meaning as such. It must be interpreted to become a medical finding. To explain the very complex cognitive procedure of the interpretation a three-level model is used. In an environment of cost containment in health care systems the quality of medical laboratory findings is very important. Analytical results are monitored by quality control procedures. For measuring the performance of medical findings the concept of the 'validity' of a laboratory test is used. Validity means the 'degree of achieving the objective'. Accordingly, a valid laboratory finding is one which correctly answers the question which the physician at the sick-bed directs to the laboratory. Quantitative measures for the validity of interpretation can be developed by an analysis of the underlying classification processes. Characteristic indices describing the validity quantitatively in terms of conditional probabilities can be derived from decision tables. Examples of 'validity indices' are diagnostic (or prognostic) 'sensitivity' and 'specificity'. These indices are powerful tools for developing strategies for the clinical use of laboratory examinations in diagnosis, prognosis and therapy management. Moreover, validity indices are appropriate output quantities for the estimation of effectiveness and efficiency of a diagnostic or prognostic examination.