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Biomedical subjects

J A Silva

Publications and source records attributed to J A Silva.

At least 19 recordsLinked to original sources
PubMed1992

Compensation and stability in nonlinear matrix models.

Stability, bifurcation, and dynamic behavior, investigated here in discrete, nonlinear, age-structured models, can be complex; however, restrictions imposed by compensatory mechanisms can limit the behavioral spectrum of a dynamic system. These limitations in transitional behavior of compensatory models are a focal point of this article. Although there is a tendency for compensatory models to be stable, we demonstrate that stability in compensatory systems does not always occur; for example, equilibria arising through a bifurcation can be initially unstable. Results concerning existence and uniqueness of equilibria, stability of the equilibria, and boundedness of solutions suggest that "compensatory" systems might not be compensatory in the literal sense.

Mathematics↗
PubMed1992

The Capgras syndrome in paranoid schizophrenia.

Capgras syndrome is characterized by a delusion of impostors who are thought to be physically similar but psychologically distinct from the misidentified person. This syndrome is generally thought to be relatively rare. Most of our knowledge about Capgras syndrome derives from single case studies and small series of cases usually from diagnostically heterogeneous groups. In this article, a series of 31 patients suffering from both paranoid schizophrenia and Capgras syndrome is described. Issues pertaining to the phenomenology of Capgras syndrome, the possible relation between Capgras syndrome and other delusional misidentification syndromes, and a neurobiological hypothesis aimed at explaining Capgras syndrome are discussed.

Adult↗
PubMed1992

The psychotherapist as witness for the prosecution: the criminalization of Tarasoff.

The "duty to protect" doctrine heralded by the Tarasoff decision seeks to prevent physical harm to third parties by psychiatric patients. Recent court cases have mandated the testimony of a criminal defendant's psychotherapist both about the Tarasoff warning itself and about confidential treatment information that was associated with the warning. One court further ruled that some clinical sessions were not psychotherapy and therefore were not afforded the protection of psychotherapist-patient privilege. The continuing erosion of confidentiality has resulted in psychiatrists and other mental health professionals becoming prosecution witnesses at the criminal trials of their own patients.

California↗
PubMed1992

Evolving misidentification syndromes and facial recognition deficits.

In this paper, the authors report the case of a 33 year old man with several misidentification delusions involving the self. Evidence suggests that one type of misidentification delusion may evolve into another type. Neuropsychological testing further suggests that misidentification delusions may be associated with subtle abnormalities in facial recognition abilities and with non dominant cerebral compromise.

Adult↗
PubMed1992

Anatomically complete heterograft mitral valve substitute: surgical technique and immediate results.

The use of a totally anatomical mitral valve heterograft as a mitral valve substitute has been proven to be technically feasible. A new stentless mitral porcine heart valve substitute was therefore developed to match the physiology and flow characteristics of the left ventricle and mitral valve complex, and tested in non-survival animal experiments. Having sought the approval of the Hospital Ethics Committee and the consent of each individual patient, this valve was implanted into 18 patients with diseased mitral valves. The duration of the procedure is approximately the same as for standard mitral valve replacement. The sizing of the valve and the anchoring of the sutures to the papillary muscle, although very straightforward, do require adherence to a protocol. The immediate clinical results are encouraging, although the first patient required a reoperation because of a patient/valve mismatch. All patients, including the patient reoperated, are in functional class I after four to 26 weeks of follow up. The patients will be followed by monthly clinical and Doppler echocardiographic examinations, as they have been so far, for the next 12 months, and annually thereafter.

Adolescent↗
PubMed1992

[Combined infarction: angiography and electrocardiographic diagnosis].

Combined infarction can be defined as the presence of ST segment elevation simultaneously in anterior and inferior leads. Their possible anatomical and physiopathological causes are suggested. Four cases of combined infarction, three of them in previously asymptomatic patients are presented, with their electrocardiographic and angiocoronarography patterns. Acute phase and 24 hours ECG ST changes are analysed and the possibility of an indirect approach to the angiographic diagnosis, is discussed.

Adult↗
PubMed1992

[Contribution of the electrocardiogram to the diagnosis of localization and extension of coronary lesions in patients with acute myocardial infarct].

UNLABELLED: With the purpose of evaluating the contribution of the ECG to the localization and extension of coronary artery lesions, 85 patients with the first acute myocardial infarction treated with thrombolysis, 79 males and 6 females (mean age 53.9 years), were studied, and the ECG changes at 3.5 and 24 hours correlated with the coronary angiographic findings before discharge. Patients were divided in two groups--Group A with anterior infarction (48 pts) and Group B with inferior infarction (37 pts). RESULTS: A) Returning of the ST downslope to baseline in inferior and anterior leads, respectively in anterior and inferior infarction at 24 h ECG, excluded associated LAD or RCA/CX lesions with a sensitivity (S) of 93% and 87% and aspecificity (E) of 60% and 58%, with a positive predictive value (PPV) of 62% and 77% and a negative predictive value of 86% and 85% respectively. All patients with anterior infarction had LAD stenosis. B) ST upslope bigger than 5 mm in V2-V3 or its presence in D-I or aVL associated to any precordial leads, diagnosed proximal LAD lesions with S of 82% and 73% and E of 75% and 73% respectively. The left axis deviation was present in 6 of 7 patients and pointed to proximal lesion. C) In Group B patients, RCA lesion was related to ST downslope in D-I, S = 77%, E = 37.5%, PVV = 80% and NPV = 33.5%, and the proximal localization (ratio between ST downslope in V2 and ST upslope in aVF) inferior to 0.5 mm with S and NPV = 80% and E and PPV = 100%. The presence of an isoelectrical ST in D-I in association with ST upslope in V5-V6 is related to CX with S and NPV = 100%, E = 85% and PPV = 25%. In conclusion, these results suggest that a careful analysis of ECG changes in patients with first acute myocardial infarction, can provide important information regarding the infarct related artery, localization of the stenosis and the presence of associated coronary artery disease, with implications in the risk stratification before hospital discharge.

Adult↗
PubMed1992

The dangerousness of persons with misidentification syndromes.

The central feature of misidentification syndromes is the presence of a delusion in which either the identity of the self or other persons is misrecognized. Recent psychiatric case reports have noted the dangerousness posed by persons with misidentification delusions. The authors report on a series of 29 individuals whose delusional misidentification was associated with aggressive behaviors. Important parameters which may assist in defining this sample of dangerous delusional misidentification syndrome persons are discussed.

Adult↗
PubMed1992

Dangerousness of the delusional misidentification of children.

Misidentification syndromes have been studied from a variety of perspectives, including phenomenological, biological, and nosological approaches. More recently, misidentification syndromes have been studied from a psychiatric-legal perspective, especially with regards to the problem of dangerousness. Capgras syndrome and other syndromes of misidentification can lead to hostile mood and subsequent physical violence. Little attention has so far been devoted to children as the objects of the psychotic person's misidentification delusion(s). We provide a review of cases from the anglophonic literature that have children as the misidentified objects, add three new cases, and then discuss the relationship between misidentification and potential harm to these children.

Adult↗
PubMed1992

The death penalty and Bernard Diamond's approach to forensic psychiatry.

Bernard Diamond would testify only for the defense in criminal cases, but only if the whole psychiatric truth would be introduced during a trial and the facts of the case supported the defense position. Otherwise, he would refuse to participate. Although few other forensic psychiatrists have personal or professional ethical concerns regarding ever participating for the prosecution, many more have such problems in capital cases. Bernard Diamond's approach to forensic psychiatry should be considered at least as an option by those opposed to the death penalty. Bias in capital cases is not a persuasive reason to withdraw from involvement if the forensic psychiatrist remains honest.

Capital Punishment↗
PubMed1991

Posttraumatic stress disorder in burn patients.

Posttraumatic stress disorder can occur in burn patients and may delay a patient's recovery. We have described the case of such a patient whose posthospital course was complicated by an untreated, coexisting PTSD.

Accidents, Occupational↗
PubMed1991

The syndrome of intermetamorphosis.

A series of 154 patients suffering from the syndrome of intermetamorphosis or its variants is discussed in terms of this misidentification syndrome's historical, classification, diagnostic, and psychosocial aspects. One case is presented in detail.

Adult↗
PubMed1991

Delusion of fetal duplication in a Capgras patient.

A case of Capgras syndrome in a pregnant patient is described. In addition to perceiving living family members as impostors, she believed that there was a double or twin of her fetus. She conceptualized her "twins" differently than the way she viewed doubles of family members. Her fetus may represent the youngest "person" to have been duplicated. The relationship of Capgras syndrome to misidentification phenomena is discussed.

Adult↗
PubMed1991

Opinions by AAPL forensic psychiatrists on controversial ethical guidelines: a survey.

A survey was conducted of a sample of AAPL members to determine their opinions on the inclusion of controversial ethical guidelines for forensic psychiatry. Members appear to appreciate the need to consider traditional Hippocratic values as at least one consideration in their functioning as forensic psychiatrists. They appear to balance their duties to an evaluee with duties to society and the legal system and to appreciate the responsibilities of multiple agency. Support was shown for interpreting ambiguities in AAPL's current guidelines in the directions indicated by most of this survey's proposed guidelines.

Attitude of Health Personnel↗