Biomedical subjects

J I Muñoz

Publications and source records attributed to J I Muñoz.

12 recordsLinked to original sources

PubMed2006

The pathology of the heart conduction system in congenital heart block.

The incidence of congenital complete heart block is estimated in 1 of 2500-20,000 births. Many cases are isolated (found in an otherwise normal heart) and the pathology of the heart conduction system is variable. We report a 51-year-old man with the diagnosis of complete heart block, with a permanent pacemaker. No family history of rhythm disturbances was available. The patient presented and endocarditis after replacement of the pacemaker battery. The prognosis was poor and the patient died three months later. Autopsy examination showed signs of shock, of septic origin. The heart was hypertrophic (450g) and the left ventricle thickened. Histopathological examination of the heart conduction system showed that the sinus and atrioventricular nodes were normal, but the His bundle was interrupted and replaced by fibrous tissue. No inflammatory signs were present. Loss of conducting fibres and their replacement by fibrous tissue is the most common pathological process in complete heart block. In this case His bundle was mostly affected, different to Lev's disease where the process is more distal (branching atrioventricular bundle) and to Lenegre's disease, which shows a diffuse damage in the conducting system.

Autopsy↗

PubMed2006

A high-performance liquid chromatography method for hypoxanthine determination in vitreous humour: application to estimation of post mortem interval.

We have developed a new technique to determine the concentration of hypoxanthine [Hx] in a reverse phase column using a modified high-performance liquid chromatography (HPLC) method that is faster and more reliable than those previously described. In this paper we present a formula for estimating the post mortem interval (PMI) based on this HPLC method by applying the inverse prediction method. The regression line obtained by changing the variables gives PMI = 0.183 [Hx] + 0.599 (PMI in hours, [Hx] in micromol/L, R2 = 0.531, P < 0.05).

Chromatography, High Pressure Liquid↗

PubMed2002

Immunohistochemical detection of fibronectin and tenascin in incised human skin injuries.

Immunohistochemical detection of molecules involved in inflammatory reaction can be useful for the diagnosis of vitality in skin wounds. We studied the expression of fibronectin (FN) and tenascin (TN) in 58 human skin wounds (48 vital and 10 postmortem). The age of vital injuries ranged from 3 min to 8 h and postmortem specimens were collected after a postinfliction interval of 15-180 min. One hundred thirty-seven formalin-fixed paraffin-embedded sections (mean: 2.3 sections per case) were stained with each of two monoclonal antibodies against FN and TN using the streptABC technique. A reticular staining for FN in wound edge and dermis was observed in 50% of vital specimens versus 0% in postmortem cases. Immunoreactivity was reduced in 10 autolysed cases. FN positivity exclusively at the injury margin was observed in 39.4% of vital wounds and 10% of postmortem cases. TN was negative in all specimens. Vital and postmortem hemorrhage areas showed positivity for FN and TN. Due to its low sensitivity, immunohistochemical analysis of FN is useful for determining vitality only in a minority of cases. Different factors in everyday practice, including autolysis and technical problems often produce false negative reactions with the result that FN cannot be regarded as a reliable parameter of vitality. Positive reactions (network staining) are more valuable than negativity but are not pathognomonic. Both vital and postmortem hemorrhages show an enhanced positivity for FN and TN, thus impeding the diagnosis.

Adult↗

PubMed2002

Demonstration of apoptosis in human skin injuries as an indicator of vital reaction.

Demonstrating the vital character of an injury and estimation of the age are routine tasks in forensic pathology and although many different techniques have been applied to this problem none have been found to be completely satisfactory. Apoptosis, an active genetically controlled process, is the major mechanism by which homeostasis of a number of physiological systems in the body is regulated and changes in the rate following different kinds of stimuli have prompted us to test it as an indicator of vitality. We used an in situ end-labelling technique (Apop-Tag) in 30 human surgical skin injuries with age since injury ranging from 3 min to 8 h and found that apoptotic keratinocytes are found in over 50% of the cases with a post-infliction interval of at least 120 min. Apoptosis was not seen in injuries less than 120 min old or in normal skin, which was used as an external control. These results suggest that apoptosis could be a useful indicator for the intravital occurrence of injuries and could help to estimate the date of the skin injuries in some cases. The importance of strict technical control is stressed and the necessity of a complementary technique to confirm apoptosis is discussed.

Adult↗

PubMed2001

Sudden neonatal death from congenital cystic adenomatoid malformation.

We report a case of congenital cystic adenomatoid malformation (CCAM) of the lungs resulting in sudden death immediately after birth. The case is extremely unusual because of the diffuse bilateral involvement. The extensive involvement of both lungs could explain the abrupt onset of the symptoms and the ineffectiveness of resuscitation attempts. The presence of cartilage as a part of the malformation adds interest to the case, since it is seldom found in this malformation and to the best of our knowledge has been reported only exceptionally in a type II CCAM.

Autopsy↗

PubMed2001

Rupture of liver cell adenoma with fatal massive hemoperitoneum resulting from minor road accident.

Blunt abdominal trauma can cause rapid death resulting from serious injuries of internal organs. The liver is commonly involved and may show tearing, usually in its upper surface, resulting in hemoperitoneum eventually leading to death. Minor trauma implies serious liver damage only when previous pathologic changes causing enlargement of the organ are present. The case of a 25-year-old woman who died as a consequence of a minor road accident is reported. At autopsy, the body showed no external injuries, the only relevant finding being a massive hemoperitoneum from the rupture of an unusually large liver cell adenoma. Liver cell adenomas carry a serious risk of spontaneous rupture, which may result in the death of the patient. The occurrence of the rupture after a minor blunt abdominal trauma is highly unusual.

Accidents, Traffic↗

PubMed2001

Detection of apoptosis in ischemic heart. Usefulness in the diagnosis of early myocardial injury.

Myocardial samples of hearts with histologic findings of acute myocardial infarction (group A), sudden coronary deaths without histologic changes (group B), and chronic ischemic heart disease (group C) were analyzed to investigate the appearance of apoptosis in acute and chronic ischemic cardiac disorders. This analysis involved the morphologic detection of DNA strand breaks in myocyte nuclei by the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay and the biochemical determination of DNA laddering in the myocardium using archival formalin-fixed, paraffin-embedded tissue sections of human myocardium. The authors demonstrated that apoptosis of myocardial cells could occur after ischemic myocardial cell injury. In all documented cases of acute myocardial infarction (group A), the infarcted area included extensive presence of both apoptosis and necrosis. In the tissue bordering on and away from the obviously infarcted areas, positive nuclei were intermingled with nonstained normal myocytes. The number of positive nuclei decreased with the distance from the infarction foci. In group B, myocardial samples showed focal or diffuse nuclear positivity of varying degrees for apoptosis, confirming the presence of myocardial ischemic cell death, whereas the histologic diagnosis remained inconclusive. This finding suggests that apoptosis could be used as a marker for acute ischemic injury. In group C, stained nuclei were dispersed with intermingled normal cardiomyocytes.

Acute Disease↗

PubMed2001

A new perspective in the estimation of postmortem interval (PMI) based on vitreous.

The relation between the potassium concentration in the vitreous humor, [K+], and the postmortem interval has been studied by several authors. Many formulae are available and they are based on a correlation test and linear regression using the PMI as the independent variable and [K+] as the dependent variable. The estimation of the confidence interval is based on this formulation. However, in forensic work, it is necessary to use [K+] as the independent variable to estimate the PMI. Although all authors have obtained the PMI by direct use of these formulae, it is, nevertheless, an inexact approach, which leads to false estimations. What is required is to change the variables, obtaining a new equation in which [K+] is considered as the independent variable and the PMI as the dependent. The regression line obtained from our data is [K+] = 5.35 + 0.22 PMI, by changing the variables we get PMI = 2.58[K+] - 9.30. When only nonhospital deaths are considered, the results are considerably improved. In this case, we get [K+] = 5.60 + 0.17 PMI and, consequently, PMI = 3.92[K+] - 19.04.

Adult↗

PubMed2001

Stature estimation from radiographically determined long bone length in a Spanish population sample.

The estimation of stature from of a variety of bones is an important aspect of forensic work. In order to obtain reliable results, it is important to have comparative data obtained from the same population group as the skeletal remains. However, lack of up to date information on the population groups of Southern Europe makes the estimation of stature from bones in this area subject to possible error. In this study, the stature of 104 healthy adults from Spain was measured, and an anteroposterior teleradiograph of the right lower and the right upper limb of every subject in the study was made in order to measure the lengths of the femur, tibia, fibula, humerus, cubitus and ulna. Pearson's regression formulae were obtained for both limbs. In males, we found the femur to be the most accurate predictor of stature (R = 0.851), whereas in females best results were obtained with the tibia (R = 0.876).

Adult↗

PubMed2000

Unexpected sudden death from coronary sinus thrombosis. An unusual complication of central venous catheterization.

Coronary sinus thrombosis is an unusual but potentially serious complication of the use of central venous devices. We report a fatal case of coronary sinus thrombosis in relation to a malpositioned central venous catheter. The death occurred very soon following the beginning of symptoms and the cause could not be suspected. Direct trauma of the catheter on the coronary sinus endothelium seems the most probable cause of the thrombosis.

Cardiac Tamponade↗

PubMed1999

Concealed homicidal strangulation by burning.

Compression of the neck, either with the hands or by a ligature, is not an uncommon method of homicide. Burning of the body to try to conceal the homicide may complicate the situation by making it difficult to interpret the findings. We hereby report two cases of homicidal ligature strangulation with extensive burning of the bodies. In both cases, external findings included the presence of a soft piece of fabric around the neck that, when removed, disclosed a portion of pale, unburned skin that vividly contrasted with surrounding areas. Osteocartilaginous lesions were present in only one case. Carboxyhemoglobin levels in both cases were very low, and the histopathologic examination of distal airways for soot particles was negative.

Aged↗

PubMedDate not supplied

Two different genetic markers for high and low myopia.

In myopia patients, Rh and acid phosphatase were typed in two groups: group 1 consisted of 214 patients with low myopia (-6 D or less); group 2 of 124 patients with high myopia (more than -6 D). Statistical analysis of the markers showed a good Hardy-Weinberg equilibrium for both groups. In the Rh system there was a significant difference between group 1 and the control population (p < 0.05), but not between group 2 and control (p > 0.1). In the case of ACP there was a significant difference between group 2 and the control population (p < 0.05), but not between group 1 and control (p > 0.25). We conclude that the observed association between myopia and Rh system (chromosome 1) involves low myopia, while the association between myopia and acid phosphatase (chromosome 2) involves high myopia. Further DNA research will lead to more specific results.

Acid Phosphatase↗