Biomedical subjects
Publications and source records attributed to A Muñoz.
Hormone binding and localization of the c-erb-A protein suggest that it is a receptor for thyroid hormone, a nuclear protein that binds to DNA and activates transcription. In contrast, the product of the viral oncogene v-erb-A is defective in binding the hormone but is still located in the nucleus.
A field study was carried out to evaluate the effect of vaccination against swine enzootic pneumonia in different production systems (closed or one-site, and open, two- or three-site, systems). The percentage of mortality showed statistically significant differences (p < 0.001) in favour of vaccination in all the production systems examined. Zootechnical and economic parameters also reflected the benefits of vaccination, although only the feed conversion ratio showed statistically significant differences (p < 0.030). A macroscopic study of lungs at slaughter pointed to statistically significant differences (p < 0.001) in favour of vaccination in the one- and two-site production systems. The histopathological and immunocytochemical study showed complete concordance with the macroscopic diagnosis (p < 0.001). Such relationship confirms the suitability of macroscopic diagnosis in field conditions.
This paper deals with digitization, using a commercial scanner, of medical documents as still images for introduction into a computer-based Information System. Document management involves storing, editing and transmission. This task has usually been approached from the perspective of the difficulties posed by radiologic images because of their indisputable qualitative and quantitative significance. However, healthcare activities require the management of many other types of documents and involve the requirements of numerous users. One key to document management will be the availability of a digitizer to deal with the greatest possible number of different types of documents. This paper describes the relevant aspects of documents and the technical specifications that digitizers must fulfill. The concept of document type is introduced as the ideal set of digitizing parameters for a given document. The use of document type parameters can drastically reduce the time the user spends in scanning sessions. Presentation is made of an application based on Unix, X-Windows and OSF/Motif, with a GPIB interface, implemented around the document type concept. Finally, the results of the evaluation of the application are presented, focusing on the user interface, as well as on the viewing of color images in an X-Windows environment and the use of lossy algorithms in the compression of medical images.
PURPOSE: The purpose of this work was to assess the advantages and disadvantages of MRI versus CT in the initial evaluation of acute infections involving the neck. METHOD: We prospectively evaluated 47 patients with neck infections. All patients underwent CT and MRI with contrast of the area of interest using similar slice thickness. Final diagnosis was achieved by percutaneous aspiration, surgical exploration and drainage, or follow-up after successful antibiotic therapy in all patients. Two radiologists reviewed all imaging studies with special attention to lesion conspicuity, location, extension, bone involvement, source of infection (odontogenic versus nonodontogenic), and presence of gas and/or calcium in the lesions. A 3 point scale was used to grade these parameters, and statistical comparison was done using paired t test. RESULTS: As used in our population, MRI was superior to CT in regard to lesion conspicuity, number of anatomic spaces involved, extension, and source. Additionally, although not statistically significantly, MRI detected a greater number of abscess collections. CT was superior to MRI in the detection of intralesional gas and calcium and showed fewer motion artifacts. These advantages of CT were, however, not significantly better than those of MRI. CONCLUSION: As used in our study, MRI was considered superior to CT in the initial evaluation of neck infections. Our findings suggest that MRI may be used as the first and perhaps the only modality to initially evaluate patients with neck infections when clinically feasible.
The morphology, infraciliature, and life cycle of Endosphaera terebrans, a suctorian endocommensal of peritrichs, have been studied with the aid of silver impregnation. The life cycle of Endosphaera terebrans begins with infection of the host cell by a small larva. The swarmer has a pointed needle-like cellular projection and two rings of cilia. The swarmer penetrates the the peritrich, loses the cilia, and then matures into an adult. The infraciliature of the adult form has four rows of barren kinetosomes that lack kinetodesmal fibers. By endogenous budding, a migratory larva is produced that leaves the host cell through the peristomial disc and that can infect other peritrichs.
UNLABELLED: Coronary angiography is the "gold standard" for the diagnosis of coronary artery disease (CAD). The aim of this work was to compare 201Thallium SPECT with different coronary angiographic cutoff values. METHODS: Data pertaining to 145 patients were tabulated. All patients underwent stress ECG, 201Thallium SPECT and coronary angiography. To assess the cutoff impact, two criteria for coronary angiography diagnosis were used: a) > or = 50% and b) > or = 75% stenosis, and applied to data from patients and vessels. RESULTS: On a patient basis, 201Thallium SPECT sensitivity, specificity and accuracy were 87%, 57% and 81% with > or = 50% cutoff and 93%, 51% and 79% with > or = 75% cutoff, respectively (NS). When performing individual vessel analysis, sensitivity, specificity and accuracy were 59%, 78% and 68% for > or = 50% cutoff and 70%, 75% and 74% for > or = 75% cutoff, respectively (p < 0.029 for sensitivity). As expected, the severer the stenosis the higher the detection rate. There were 19 patients who had stenosis between 50% and 74%. Of these, 21% had abnormal stress ECG and 58% abnormal Thallium-201 SPECT. CONCLUSION: 201Thallium SPECT results support the use of > or = 50% stenosis cutoff criteria for CAD diagnosis and evaluation. Combined with coronary angiography, myocardial SPECT offers an excellent management strategy to patients.
Thyroid hormones (TH) are essential for somatic and neural development. Epidemiological studies have pointed to TH-dependent craniofacial features occurring during development. In an attempt to elucidate the precise role of TH in the developing eyes and adnexa (orbit, lids, nasolacrimal structures), we analysed the craniofacial and eyeball developmental characteristics in a rat model of congenital-neonatal hypothyroidism (HG), induced by combined chemical-surgical thyroidectomy. The heads and eyeballs from control and HG animals were obtained at key developmental stages and processed for scanning electron, light and transmission electron microscopy. On embryological day 13 (E13), significantly reduced values for head parameters (25% less), optic primordia area (0.053 +/- 0.0085 vs. 0.111 +/- 0.012 microm(2); p < 0.05) and volume (3.96 +/- 0.141 vs. 8.09 +/- 0.123 microm(3); p < 0.05) were found in the HG with respect to the controls. In addition, a delayed prenatal eye closure and postnatal eye opening took place in the treated rats. The photoreceptor and ganglion cell layer thickness displayed significantly lower values (p < 0.001) in HG, at each developmental time point. Postnatally, a delay in photoreceptor outer segment morphogenesis (in relation to retarded disc formation) and significantly lower values for ganglion cell nuclear volumes (p < 0.001) and nuclear pore density (p < 0.01) were observed in the TH-deficient animals. All data suggest that TH play a pivotal role in the development of the face and eye. Therefore, a series of defects due to a loss of TH actions involved in anterior-posterior development of the head and face and the loss of TH-dependent signals crucial for cell differentiation, migration, proliferation and establishment of definitive cell phenotypes in the eyes may appear. Gestational and neonatal screenings for thyroid functioning are suggested to paediatricians and ophthalmologists in order to prevent craniofacial malformations and visual abnormalities.
AIMS AND BACKGROUND: Neoadjuvant chemotherapy for head and neck carcinoma is still an important treatment modality. The prognostic value of patient and tumor parameters has been extensively evaluated in several trials, yielding mixed results. We report the prognostic factors emerging from a group of patients undergoing neoadjuvant chemotherapy. PATIENTS AND METHODS: From April 1986 to June 1992, 149 consecutive patients received cisplatin-5-fluorouracil-based neoadjuvant chemotherapy. After four courses of chemotherapy, patients underwent local-regional treatment with surgery, radiation or both. A variety of patient and tumor characteristics were evaluated as predictors for response to chemotherapy and survival. RESULTS: The complete response, partial response and no response rates to NAC were 52%, 33% and 15%, respectively. No parameters predicted response to chemotherapy. At a maximum follow-up of 87 months, overall survival was 39% and disease-free survival was 49%. Variables shown to be predictors of survival in univariate analyses were age, performance status, histology, site, T, N, stage, and response to chemotherapy. Using the Cox regression analysis, only complete response to induction chemotherapy (P = 0.0006), performance status (P = 0.03), stage (P = 0.01), age (P = 0.03) and primary tumor site (P = 0.04) emerged as independent prognostic factors for survival. CONCLUSIONS: Complete response to chemotherapy was confirmed as the strongest prognostic factor influencing survival. However, conventional clinicopathologic factors did not predict response, hence, potential prognostic biologic and molecular factors for response must be sought. At present, much effort must be made for the improvement of the complete response rate, which seems to be a requisite to prolong survival.
Results of a HIV prevalence study conducted in hemophiliacs from Belo Horizonte, Brazil are presented. History of exposure to acellular blood components was determined for the five year period prior to entry in the study, which occurred during 1986 and 1987. Patients with coagulations disorders (hemophilia A = 132, hemophilia B = 16 and coagulation disorders other than hemophilia = 16) were transfused with liquid cryoprecipitate, locally produced, lyophilized cryoprecipitate, imported from São Paulo (Brazil) and factor VIII and IX, imported from Rio de Janeiro (Brazil), Europe, and United States. Thirty six (22%) tested HIV seropositive. The univariate and multivariate analysis (logistic model) demonstrated that the risk of HIV infection during the study period was associated with the total units of acellular blood components transfused. In addition, the proportional contribution of the individual components to the total acellular units transfused, namely a increase in factor VIII/IX and lyophilized cryoprecipitate proportions, were found to be associated with HIV seropositivity. This analysis suggest that not only the total amount of units was an important determinant of HIV infection, but that the risk was also associated with the specific component of blood transfused.
Explore the source record for details and available documents.
OBJECTIVE: Standard survival analysis methods are useful for data involving censored cases when cures do not generally occur. If the object is to study, for instance, the development of a complication in the progress of an infectious disease, some people may be cured before complications develop. In this article, we provide methods for the analysis of data when cures do occur. An example is a study of prognostic factors for pancreatic abscess in patients with pancreatitis, some of whom leave the risk set because the pancreatitis clears. DESIGN: We present methods for estimating the survival curves and comparing hazard function for two objectives: (1) the occurrence of an abscess, irrespective of whether the patients are cured or not, and (2) the occurrence of an abscess for patients who, at that stage, have not been cured. PATIENTS: We illustrate the applications of the methods using a sample of 50 patients with severe pancreatitis. RESULTS: To study the occurrence of an abscess, regardless of whether the patients are cured or not, we show that the appropriate strategy is to assign to the cured patients an infinite time to the appearance of an abscess. If the cured were considered censored at the moment the pancreatitis cleared, this would result in an overestimation of the hazard of presenting an abscess. On the other hand, if the objective is to compare the occurrence of abscess according to an exposure for patients who have not been cured, one needs to censor the cured patients at the time they are cured. CONCLUSIONS: For the analysis of survival data in the context of infectious diseases when cure is possible, it is important to use a censoring strategy that is pertinent to the specific aims of the study. Considering cures as censored at the time of cure is not always appropriate.
OBJECTIVE: To present the experience of vascular malformations (VM) of the central nervous system (CNS) in children obtained in our centre. Since these lesions do not often present clinically in childhood, there are few series described in the literature. PATIENTS AND METHODS: We made a retrospective review of the clinical histories of patients with VM of the CNS shown on MR, angiography and/or morbid anatomy, who were aged 15 years or under. Patients with Sturge-Weber or Von Hippel-Lindau syndromes were excluded. RESULTS: We describe 32 patients with VM of the CNS. Twenty four had arteriovenous malformations (AVM), 5 had cavernous malformations (CM), 2 had malformations of Galeno's vein (MGV) and one patient had a congenital fusiform arterial aneurysm. Twenty two children (68%) presented clinically with hemorrhages. This was the form of presentation in 20 patients with AVM. In 4 of the 5 patients with CM the first sign was epileptic crisis. The two patients with MGV presented with macrocephaly, in one neonate it was associated with heart failure and in on older baby with hydrocephaly. The patient with a congenital arterial aneurysm presented with paroxystic episodes of facial pain. CONCLUSIONS: The AVM are the VM which most frequently cause symptoms in childhood.
In attempt to identify the possible role of mayor genes, multifactorial inheritance, and cohort effects in the susceptibility to idiopathic epilepsy with generalized tonic clonic seizures of the awakening type (GTCS), complex segregation analysis was performed in 196 nuclear families ascertained through affected with probands with idiopathic epilepsy with GTCS belonging to the Paisa community of Antioquia (Colombia). Models postulating no transmission, single mayor locus (dominant and recessive) only, and multifactorial component only, were rejected. The models postulating no polygenic component to transmission, and no transmission of the major effect were also rejected. Thus far, complex segregation analysis suggested that a major autosomal codominant allele together with a multifactorial component (mixed model) best explains clustering of idiopathic epilepsy with GTCS in families of the Paisa community. The deficit of transmission of heterozygotes (0.17) is compatible with the existence of epistasis acting on a major gene whose frequency was estimated to be 0.0211. Its transmission variance accounts for 81% of the susceptibility to idiopathic epilepsy with GTCS. The complementary variance (19%) is due to polygenic component.
INTRODUCTION: Arterial dissection is the cause of 20% of the stroke occurring in adults under the age of 45. The existence of recurrence has been discussed in recent studies, and the overall frequency estimated as 4% to 8%, with a risk of 1% per year. The course of the condition is usually oligosymptomatic, so that a high index of suspicion is necessary for diagnosis to be made. We consider that different connective tissue disorders and anomalies of the vascular wall predispose to dissection. It would seen reasonable to think that these same anomalies may lead to recurrence. However, this cannot always be demonstrated. A family history of dissection is also an important factor in recurrence. CLINICAL CASES: We present two cases of recurrent spontaneous dissection of the carotid artery from a series of 22 patients with dissection, during the period 1990-1997. In the first case, the second dissection occurred 15 days after the first and in the second case, seven months later. In both cases the recurrence was in the contra-lateral carotid artery. In the second case the vascular tree was noted to have been formed of ecstatic, tortuous vessels. CONCLUSIONS: Our series shows results similar to others published. In one of these, an underlying arteriopathy which predisposed to the condition was shown. Both followed satisfactory courses. In case 2 a high index of clinical suspicion was necessary, since the recurrence presented as headache alone.
Spontaneous retropharyngeal hematoma is an uncommon entity that is difficult to diagnose and may progress rapidly to airway obstruction. We report a case of a 53-year-old man with acute onset of retropharyngeal pain, dysphonia, and dysphagia after vomiting. On CT, a nonspecific retropharyngeal collection was seen. MR imaging demonstrated blood products, suggesting a diagnosis of retropharyngeal hematoma, and the patient was managed conservatively. MR imaging allowed specific diagnosis of a rare condition that is otherwise difficult to diagnose without surgical intervention.
GOAL: During 1999, as in previous years, the NADYA-SENPE Group has maintained an annual register of patients with Artificial Nutrition at Home in order to keep up to date our available knowledge of this therapy. The present paper analyzes the results of the sixth National Register of patients under treatment with Enteral Nutrition at Home corresponding to 1999, produced with the co-operation of twenty-three centres in the Spanish national health network. MATERIAL AND METHODS: The data were collected through a closed questionnaire included on our web site (www.nadya-senpe.com). Apart from epidemiological information, the form includes the indication that led to the prescription of nutrition, nutritional treatment, access path, complications and admissions to hospital, follow-up of the treatment, patients' quality of life and progress. All of the data are processed by the co-ordinating team. The Nutrition Unit at La Paz Teaching Hospital in Madrid has acted as the group co-ordinator. RESULTS: During 1999, a total of 2,262 patients at the twenty-three collaborating centres followed treatment with Home Enteral Nutrition (NED in its Spanish acronym). The mean age was 63.6 (19.67 years (males: 57.6%; females: 42.3%). The mean time with nutritional treatment is 5.89 (4.25 months. The neurological alterations (37.5%) and neoplasias (36.8%) were the most frequent indications for NED. Most patients used oral administration (50.7%), the use of artificial routes is less frequent, with 5NG being used on 27.9% and PEG on 12.7%. The polymeric formulas are the ones most commonly used (87.7%). The number of complications recorded amounted to 1,403 episodes, representing 0.62 complications per patient per year, of which 40.8% were gastro-intestinal (0.26 complications per patient per year) and 18.7% were mechanical complications, with only 9 recorded cases of bronchoaspiration. It was necessary to admit patients to hospital on 836 occasions (0.38 admissions per patient), albeit generally for causes not associated with nutrition (86.1%). At year-end, 51.4% of patients continued to receive nutritional support. CONCLUSIONS: Enteral nutrition at home is a safe technique whose use is growing in Spain. It requires the existence of appropriately equipped nutrition teams as well as the collaboration of the Primary Health Care services and the suitable training of patients and relatives. It is essential to progress more deeply into the development and application of clinical routes that provide a clear and concise methodology covering all nutrition-related aspects. In itself, nutrition is a therapeutic alternative regardless of whether access is obtained through a natural or an artificial route. It is necessary for the persons responsible for health-care administration to realize that the appropriate nutrition of patients leads to an improvement in their general health, a shorter course for their illness and, therefore, a reduction in costs.
INTRODUCTION: Temporal lobe epilepsy is associated to many disorders localized to the neocortex, the hippocampal formation or both (dual pathology). The most common pathologies are mesial sclerosis, tumours, malformations and scars. However, these alterations are not intrinsically epileptogenic, as they are also seen in patients who do not develop epilepsy. Thus, the cortical tissue in the damaged brain undergoes changes that may become a primary epileptogenic region. This region, in turn, may induce the formation of secondary epileptogenic regions situated at some distance from the primary focus. DEVELOPMENT: In this paper we consider the possibility that in both the primary and secondary epileptogenic regions there are similar changes in the neuronal circuits which induce epileptic activity. In the case of the primary epileptogenic regions, these changes occur non specifically following an initial lesion or precipitating factor (e.g. a tumour) which induces gliosis and neuronal loss around the lesion. These changes give rise to a perilesional synaptic reorganization (elimination of connections with or without the formation of new synapses) which causes the onset and continuation of epileptic activity. However, the changes in the circuits in the secondary epileptogenic regions are the result of epileptic activity originated in the primary epileptogenic region which is propagated by specific anatomical connections. This anomalous activity causes changes in the target region (gliosis and neuronal loss) which leads to epileptogenic synaptic reorganization similar to that occurring in the primary perilesional areas.
Three brothers 9, 12, and 14 years of age were studied. The three of them fulfilled the diagnostic criteria of Marfan Syndrome that was made based on physical and ophthalmologic examination, these criteria included musculoskeletal abnormalities, subluxation of lens, myopia and aortic aneurysm. The three siblings died due to complications of the aortic aneurysm, which had an early onset as well as the other clinical manifestations of the disease. They were 2 brothers and one sister. There was neither mental or psychomotor retardation, nor metabolic disease in any of the patients. Family history did not show any clinical manifestation of the disease in parents or grandparents. We propose that the hereditary pattern is recessive autosomic instead of dominant autosomic given the features of these cases and their history.