Biomedical subjects

M L Kaplan

Publications and source records attributed to M L Kaplan.

At least 19 recordsLinked to original sources

PubMed1997

Violence and homicidal behaviors in psychiatric disorders.

Our review evaluating the relationship between violent/homicidal behaviors and mental illness/psychiatric disorders used many different data including that assessing the prevalence of violent/homicidal behaviors in former psychiatric inpatients (just before hospitalization, during hospitalization, and after discharge) as outpatients and in community samples as well as evaluating the prevalence rate of psychiatric disorders in people who actually engaged in violent/homicidal disorders (jail detainees, prison inmates, and community samples). Irrespective of which line of investigation, there was convincing evidence that violent/ homicidal behavior was associated significantly with mental illness. Although earlier investigations failed to control for important variables, such as age and sociodemographics, most studies reviewed in this article did control for these items, further underlining the association of violence and mental illness. The question of whether specific psychiatric diagnostic categories are associated with violent/homicidal behavior is less definite across the various studies reviewed. The presence of substance abuse and dependence and alcohol abuse and dependence as well as antisocial personality disorder are particularly associated with an increased risk of violent/homicidal behaviors. The risk for these latter behaviors in schizophrenia, mood disorders, and anxiety disorders may appear somewhat greater than that for a general population but are not of the same magnitude of that for substance abuse or antisocial personality disorder. Interestingly, our outpatient study found that homicidal behaviors were not associated with any specific psychiatric diagnosis. Although understanding whether specific psychiatric diagnostic categories are more prone to violent behaviors may be of importance, most studies have been shortsighted regarding this evaluation. All the studies presented in this article except the ECA project, presented diagnostic data where either the presence of one psychiatric disorder did not preclude the diagnosis of another or assigned subjects/patients into the severest disorder of a predetermined hierarchy of diagnoses or only selected their principal/primary diagnosis. Thus, the effect of having a solitary psychiatric disorder (only one disorder present) as well as the effect of comorbidity per se on the relationship of psychiatric disorders and violent/homicidal behaviors were unexplored. Only the ECA study by Swanson and colleagues reported on the effect of comorbidity. As reviewed earlier in the article, Swanson et al found that comorbidity of psychiatric diagnostic categories further increased the risk of violent/ homicidal behaviors. In most cases, it was many more times than simply adding the rates of either diagnosis alone. Because more than 54% of respondents of the National Comorbidity Survey study who had one DSM-III-R diagnosis also had at least a second Axis I diagnosis, the association of violent/homicidal behaviors to mental illness may even be stronger than originally believed. Within the relationship of violent/homicidal behaviors and mental illness, this article suggests a number of particular risk factors. As just reviewed, substance/alcohol abuse and antisocial personality disorder as well as the presence of comorbid psychiatric disorders are significant risk factors. Which particular comorbid illness increases the risk still needs further elaboration. Studies must continue to try to define and understand the relationship of violent/homicidal behaviors in mental illness. Although mental disorders per se are significantly associated with violent/homicidal behaviors, it is reasonable to believe that targeting certain subgroups of patients should be helpful. Probably the presence of psychotic symptoms is a significant risk factor in violent/ homicidal behaviors in the mentally ill. Only one of the studies reviewed in this article evaluated this issue. (ABSTRACT TRUNCATED)

Adult↗

PubMed1997

Soluble amylose cornstarch is more digestible than soluble amylopectin potato starch in rats.

In liquid enteral formulations, high molecular weight soluble starches may be able to replace glucose and low molecular weight glucose polymers that have high glycemic indices. Male rats were fed either commercial cornstarch, dextrose, modified soluble potato (70-75% amylopectin) starch, or modified soluble amylomaize-7 (70% amylose) starch for 4 wk. Body weights did not differ among the groups. Food consumption was significantly higher in the two modified starch-fed groups than in the two control groups. Commercial cornstarch, dextrose, modified potato starch and modified amylomaize-7 starch were 100 +/- 0, 100 +/- 0, 69.0 +/- 1.0 and 91.5 +/- 0.8% digestible, respectively (n = 9, mean +/- SEM). The modified potato starch-fed group deposited the least fat, protein and energy. In both modified starch-fed groups, liver weights were significantly greater than in the two control groups. In food-deprived rats, serum free fatty acid concentrations in the modified potato starch-fed group were significantly higher than in the two control groups, and serum glucose concentrations were significantly higher in the two modified starch-fed groups than in the controls. The insulin to glucagon ratios were significantly lower in the modified potato starch-fed and amylomaize-7 starch-fed groups than in the dextrose-fed control group. Serum protein concentrations, measured after food deprivation, were significantly lower in the modified potato starch-fed group than in the other three groups. Gluconeogenesis from fermentation products might account for the high serum glucose concentrations in the two experimental groups. These data indicate that only the modified amylomaize-7 starch may be useful in the development of food products for liquid nutritional supplements because of the high digestibility and the low resultant insulin levels.

Adipose Tissue↗

PubMed1996

Prevalence and characteristics of physical and sexual abuse among psychiatric outpatients.

Eighty-six female and 34 male psychiatric outpatients completed a self-report questionnaire that retrospectively assessed their history of physical and sexual abuse and assault. Seventy percent reported an abusive experience in childhood or adulthood. Female subjects were more likely than male subjects to report childhood sexual abuse and adult physical and sexual assaults. For all subjects, childhood sexual abuse was associated with adult sexual and physical assault. The charts of several patients who reported abuse histories did not include any record of abuse.

Adolescent↗

PubMed1995

Animal model for evaluating the effect of systemic estrogen deficiency on residual ridge resorption.

The rate of resorption of residual ridges after tooth extraction varies among subjects. Despite many human studies, the etiologic factors of severe forms of resorption of residual ridges are unknown and probably multifactorial. To facilitate investigations of resorption of residual ridges, it is preferable to use an animal model with a dentoalveolar component similar to that of human beings. This study developed a rapid, nonhuman primate model in which one could measure resorption of residual ridges at the most critical period, with the least amount of time, minimal operation, and the least interference with normal nutrition. Three female Macaca fascicularis monkeys, 7 to 9 years old, were selected for simple extraction of four maxillary incisors, four mandibular incisors, and two mandibular canines. Lateral cephalographs were taken at weeks 0, 1, 2 to 3, 5 to 6, 8 to 9, 11 to 12, and 26 to 28 after extraction with a newly constructed cephalostat that allowed easy reproducibility of animal placement in the prone position. Height and area measurements were made of maxillary and mandibular anterior residual ridges in the superimposed cephalographs. Sequential mean bone loss data produced bone loss curves similar to those observed in humans. One animal underwent ovariectomy. The plasma levels of both estrogen and progesterone decreased over 25 days and stayed below the detection limits thereafter. Tooth extraction was done 4 weeks after the ovariectomy and the bone resorption pattern was able to be observed longitudinally with the newly established monkey cephalostat. The results indicated that Macaca fascicularis need not be sacrificed when used in longitudinal studies of resorption of residual ridges in a relatively short period of experimental time. This model can provide an excellent opportunity to investigate a causal relationship between the rate of resorption of residual ridges and predisposing systemic factors such as estrogen deficiency.

Alveolar Bone Loss↗

PubMed1995

Early treatment of obese (ob/ob) mice with triiodothyronine increases oxidative metabolism in muscle but not in brown adipose tissue or liver.

We explored the possibility that early replacement of low triiodothyronine (T3) may improve the low oxidative metabolism in metabolically important tissues of ob/ob mice. Triiodothyronine doses (2.5 to 25.0 micrograms/100 g body wt) were injected intraperitoneally into ob/ob and non-ob/ob mice daily from 3 wk until 6 wk of age. Untreated ob/ob and non-ob/ob mice were injected with saline (pH 9.1). Food intake was equalized across all groups. At 6 wk of age, the O2 consumption of muscle, white and brown adipose tissues, and hepatocytes was measured. The saline-treated ob/ob mice showed lower muscle weights, higher fat pad and liver weights, and larger fat cell sizes than saline-treated non-ob/ob mice. In ob/ob mice, tissue O2 consumption was the same in muscle, lower in brown and white adipose tissues, but higher in liver compared with values in non-ob/ob mice. Triiodothyronine treatment in ob/ob mice resulted in lower values for body weight, liver weight, hepatocyte number, liver protein, epididymal fat pad weight, and white adipocyte number and size than in saline-treated ob/ob mice. Triiodothyronine treatment increased soleus muscle, liver and brown adipose tissue O2 consumption in non-ob/ob mice. In ob/ob mice, triiodothyronine increased only soleus muscle O2 consumption and required higher doses than in non-ob/ob mice to achieve an effect. These data are consistent with the concept of tissue triiodothyronine resistance in ob/ob mice. Low triiodothyronine levels and tissue resistance to triiodothyronine might be important early defects in this obesity syndrome.

Adipose Tissue↗

PubMed1994

Suicide assessment: clinical interview vs. self-report.

This study examined whether patients disclosed the same information about suicidal behaviors on a self-report instrument that they conveyed to a clinician in a face-to-face interview. The results indicated a generally high level of agreement between these two forms of suicide assessment. The one exception was the question that concerns recent suicidal ideation, where patients tended to disclose more on the self-report form.

Adult↗

PubMed1994

Cardiac adaptations to chronic exercise in mice.

Transgenic mice can be created to serve as models of human cardiac disease. Despite the technology available to manipulate the cardiovascular system of the mouse, there is relatively little information available concerning the normal physiology of the mouse heart. Therefore, we have characterized the response of the adult mouse to chronic physical conditioning by swimming. Adult female C57/B16 mice were conditioned by swimming up to 90 min twice daily for 4 wk, resulting in a 10% increase in heart weight and a 16% increase in heart weight-to-body weight ratios compared with sedentary controls. The heart rate response to a submaximal work load decreased > 20% with this conditioning program. Succinate dehydrogenase activity increased markedly in the soleus muscles of the conditioned animals, from 28 +/- 3 to 44 +/- 3 nmol.mg-1.min-1. In contrast to these changes, which also characterize the exercise model in the rat, no increase in cardiac tissue norepinephrine content or in cardiac myosin or myofibrillar adenosinetriphosphatase (ATPase) activities was observed, and no change in the V1 predominant myosin isoform or alpha-myosin heavy chain mRNA profiles was seen in the hearts of the swimmers. This study establishes that mice are able to develop cardiac hypertrophy in response to chronic conditioning which is not associated with changes in the ATPase activities of cardiac muscle. These data should be of use to investigators using murine models to define the molecular basis of adaptive cardiac hypertrophy in vivo.

Adaptation, Physiological↗

PubMed1994

Tetracycline-regulated cardiac gene expression in vivo.

Tight regulation of foreign genes expressed in vivo would facilitate studies of many biologic processes and would be useful for gene transfer-based therapies. To test the ability of a tetracycline-regulated gene expression system to function in vivo, we directly injected chimeric tet repressor-VP16 transactivator expression plasmids and luciferase target genes into the hearts of adult rats. Cardiac luciferase activity increased over two orders of magnitude in response to small changes in input tetracycline-controlled transactivator DNA. Transactivation was repressed to background levels by subtherapeutic concentrations of tetracycline in a dose-dependent manner. Target gene expression could be rapidly and reversibly controlled by manipulating antibiotic administration. This system may be particularly useful for in vivo studies of gene function or gene therapies where the timing or extent of expression are critical variables.

Animals↗

PubMed1994

Homicidal behaviors among psychiatric outpatients.

OBJECTIVE: Most studies of violent behavior among psychiatric patients focus on inpatients or patients recently discharged from psychiatric units. To explore violent behavior among patients living in the community, the authors examined the prevalence of homicidal behaviors in a general psychiatric outpatient population. METHODS: During an intake evaluation, 517 outpatients completed several self-report instruments that included a detailed survey of past and current homicidal behaviors covering homicidal ideation, plans, and attempts. Demographic and clinical characteristics of patients with and without a history of homicidal behaviors were compared. RESULTS: Twenty-two patients (4 percent) reported a past homicide attempt. Patients who reported homicide attempts could be distinguished from patients with no homicidal behaviors by the presence of other aggressive behavior such as suicidal ideation and suicide attempts by themselves and their family members and by elevated current measures of interpersonal sensitivity, hostility, and paranoid ideation. CONCLUSIONS: The rate of homicide attempts in the general outpatient population studied was considerably lower than the reported rates of assault among inpatients. The relationship between past and current episodes of aggressive behavior reinforces the importance of including a careful assessment of past history of violent behaviors as part of the routine psychiatric evaluation.

Adolescent↗

PubMed1994

Early treatment of obese (ob/ob) mice with triiodothyronine increases oxygen consumption and temperature and decreases body fat content.

An early abnormality in the ob/ob mouse is a low circulating level of the thyroid hormone, triiodothyronine (T3). The possibility was explored that early T3 treatment of ob/ob mice will increase oxidative metabolism and lower body fat content. Doses of T3, ranging from 0.0 to 25.0 micrograms/100 g body wt were injected, ip, into ob/ob and non-ob/ob mice daily from 3 weeks until 6 weeks of age. Food intake was equalized across all groups to that consumed by non-ob/ob saline-treated group. At 6 weeks of age, body weight, serum concentrations of thyroxine (T4), T3, insulin and glucose, oxygen consumption, colonic temperature, and body composition were analyzed. T3 treatment decreased body weight, increased body oxygen consumption, increased colonic temperature, and decreased body fat without a significant change in body protein in ob/ob mice. T3 treatment also increased serum T3, and decreased serum T4, insulin, and glucose concentrations in ob/ob mice. Because total body protein did not change as a result of T3 treatment, the increased oxidative metabolism due to T3 treatment was probably via the change of metabolic activity of the total lean body mass or the specific metabolically active tissues in the ob/ob mice, such as brown adipose tissue, liver, or muscle.

Adipose Tissue↗

PubMed1993

Distinct behavior of cardiac myosin heavy chain gene constructs in vivo. Discordance with in vitro results.

Transcriptional thyroid hormone responsiveness of the cardiac alpha-myosin heavy chain (alpha-MHC) gene has been demonstrated in transfections into fetal and neonatal cardiomyocytes and in transgenic mice. However, the correspondence between the regulation of MHC expression in dissociated cells with that in the intact heart is unclear. Given the cost and time involved in generating multiple transgenic lines for the characterization of gene regulatory elements, we used direct cardiac gene transfer to identify elements regulating both basal and thyroid hormone responsive cardiac alpha-MHC gene expression in the adult heart in vivo. Sequences upstream of the rat alpha-MHC gene linked to a luciferase reporter gene were injected into the hearts of adult rats subjected to various thyroid manipulations. The 161-bp sequence upstream of the transcription start site, which contains a TATA box, a CCAATT box, and a thyroid hormone response element, was transcriptionally active but not thyroid hormone responsive. The expression of a construct containing 388 bp of upstream sequence was increased by thyroid hormone administration, a response that required an intact thyroid hormone response element. However, expression of this construct failed to decrease to basal levels in a hypothyroid state. To confer complete (positive and negative) thyroid hormone regulation, 2,936 bp of upstream sequence was sufficient. These results demonstrate that, although necessary, the thyroid hormone response element is not sufficient for complete thyroid hormone regulation of this gene in vivo. In addition, DNA sequences regulating the quantitative expression of cardiac alpha-MHC in the euthyroid state have been demonstrated.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1993

Suicidal behaviors in adult psychiatric outpatients, I: Description and prevalence.

OBJECTIVE: Because the findings of previous studies of suicidal behaviors in psychiatric outpatients may not necessarily generalize to outpatients with a wide spectrum of psychiatric diagnoses, the authors evaluated the prevalence of suicidal behaviors in a large general psychiatric outpatient clinic whose patients represented a full spectrum of psychiatric illness. METHOD: A total of 651 patients participated in the study between 1987 and 1989. These patients had sought treatment at the outpatient psychiatry department of a private nonprofit hospital. Before being interviewed for treatment, all patients were given a comprehensive self-rating survey packet that included the Harkavy Asnis Suicide Survey and the Hopkins Symptom Checklist-90. The Harkavy Asnis Suicide Survey is a self-report questionnaire that assesses demographic variables, current and past history of suicidal behaviors of the patient as well as family members and peers, and a detailed description of each previous attempt. RESULTS: Fifty-five percent of the patients had a history of suicidal ideation, and 25% reported at least one previous suicide attempt. Approximately half of the suicide attempters reported multiple attempts. The predominant methods of attempt were overdose (53%), jumping (17%), and wrist cutting (17%). Suicidal behavior was prevalent in most diagnostic groups. The rates of suicidal ideation among patients with mood disorders (major depression, dysthymia, and bipolar disorder), adjustment disorders, and alcohol/substance abuse were significantly greater than that of the patients with generalized anxiety disorder. CONCLUSIONS: The authors conclude that suicidal behavior is prevalent among patients who seek treatment in a general outpatient department.

Adjustment Disorders↗

PubMed1992

Behavior of genes directly injected into the rat heart in vivo.

Gene transfer can be achieved in the adult rat heart in vivo by direct injection of plasmid DNA. In this report we define the spatial and temporal limits of reporter gene expression after a single intracardiac injection. pRSVCAT (100 micrograms), in which the Rous sarcoma virus long terminal repeat is fused to the chloramphenicol acetyltransferase reporter gene, and p alpha MHCluc (100 micrograms), in which the alpha-cardiac myosin heavy chain promoter is fused to the firefly luciferase gene, were injected into hearts, and reporter gene activities were assayed at various times. Both chloramphenicol acetyltransferase and luciferase were detectable in 100% of the rats from 1 to 7 days, in 60% of the rats from 17 to 23 days, and in 30% of the rats from 38 to 60 days after injection. Reporter gene activity was largely limited to a 1-2-mm region of the ventricle surrounding the injection site. Closed circular DNA was far more effective than linear DNA in transfecting cells in vivo. The relative strengths of three different promoters, Rous sarcoma virus long terminal repeat, alpha-myosin heavy chain, and alpha 1-antitrypsin, all fused to the luciferase reporter gene were determined. The constitutive viral promoter was approximately 20-fold more active than the cardiac-specific cellular promoter, and the liver-specific cellular promoter was not active at all in the cardiac environment. Thus, direct injection of genes into the heart offers a simple and powerful tool with which to assess the behavior of genes in vivo.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1991

Hormonal modulation of a gene injected into rat heart in vivo.

We demonstrate gene transfer into rat heart in vivo by the direct injection of plasmid DNA. Injection of gene constructs driven by retroviral and cellular promoters resulted in detectable levels of reporter gene activities. The cellular promoter and 5' flanking sequence (positions -613 to +32) were derived from the rat alpha-myosin heavy chain gene whose expression in vivo is restricted to cardiac muscle and is positively regulated by thyroid hormone. After DNA injection, activity of the firefly luciferase gene coupled to the myosin heavy chain promoter and regulatory sequence was detected in heart but not in skeletal muscle and was significantly increased in response to thyroid hormone treatment. Consequently, expression of injected genes can be targeted to specific cell types in vivo and can be modulated by the hormonal status of the animal. This approach provides a means of mapping the elements of genes that regulate their responses to complex stimuli that cannot be modeled in vitro.

Animals↗

PubMed1991

The self-organization of human psychological functioning.

This article describes the traditional model of human psychological functioning which dominates current theorizing, contrasts it with the new, emerging perspective of self-organizing processes, and applies this new approach to a theory of human psychological functioning. In the traditional model there is an assumption that processes of functioning are discretely different from physical structure. This assumption is shown to be intrinsic to a linear conceptual framework which implies that (a) stability of functioning derives from physical structure; (b) functioning is determined by the effects of enduring, antecedent components; (c) the environment can selectively influence structure; and (d) observational methods are capable of accessing and revealing processes of functioning. In the contrasting self-organizational perspective, structure and functioning are assumed to be given in one another at the level of organizational process. This formulation implies that as a system functions (a) its orderliness and stability are being determined by the ongoing functioning itself; (b) at the level or organizational functioning there are no antecedent structures separate from consequent activity; (c) systemic functioning exists as a unitary and continuous organizational process; and (d) organizational functioning cannot be instructed by environmental events. The work of Prigogine and of Maturana are examined as a basis for a theory of human psychological functioning as a self-organizing system. The theory that is proposed describes how attentional and experiential functioning evolve as a system of organizational continuity and coherence and how the process by which people recognize and identify their functioning secures this organizational functioning.

Adaptation, Psychological↗

PubMed1991

Inhibition of alveolar bone loss in beagles with the NSAID naproxen.

The non-steroidal anti-inflammatory drug(NSAID) naproxen was studied in 11 beagle dogs over a 13-month period to determine its effect on the progression of periodontitis. Following a 6-month pretreatment period, 5 dogs received naproxen daily at a dosage of 2.0 mg/kg for 1 month, then 0.2 mg/kg for 6 months. Six control dogs received a gelatin capsule daily as placebo. Standardized radiographs were used to measure the rate of bone loss during the pretreatment and treatment periods. In the control dogs, the rate of bone loss was seen to increase during the treatment period although the increase was not statistically significant. In dogs treated daily with naproxen, the rate of bone loss in the treatment period was significantly less at 4 months of treatment; however, at 7 months the difference, though lower than pretreatment rate, was not significant. When the percent change in rate of bone loss during the overall 7-month treatment period was compared with pretreatment rate, the control dogs demonstrated a 38% increase in rate of bone loss during the treatment period contrasting with a 61% decrease in bone loss rate in naproxen-treated dogs. The data indicate that the non-steroidal anti-inflammatory drug naproxen can significantly inhibit alveolar bone loss in beagles. At 4 months of treatment the rate of bone loss in the naproxen-treated dogs was significantly less than pretreatment, but at 7 months of treatment the rate was no longer statistically significantly less than baseline. This probably reflects a dose response to naproxen treatment for, after 30 days of the treatment period, the naproxen dosage was reduced 10-fold due to tolerance by the beagle.

Alveolar Bone Loss↗

PubMed1991

Oxygen consumption of muscles from ob/ob and Ay/a strains of obese mice.

Oxygen consumption was measured in the in vitro preparations of soleus, extensor digitorum longus, gracilis, and diaphragm muscles from young ob/ob obese mice. In young Ay/a obese mice, similar measurements were made with in vitro preparations of soleus, gracilis, and diaphragm muscles. These young obese mice were heavier than their nonobese littermates. Muscle weights were similar in obese and nonobese mice. In the Ay/a obese mice, values of muscle oxygen consumption were similar to those found in the a/a nonobese littermates. This correlates well with other known information about the Ay/a variety of obesity. In the ob/ob obese mice, values of oxygen consumption in the gracilis and diaphragm muscle preparations were lower than those in nonobese littermates. These data indicate that some muscles in the ob/ob obese mice contribute to the depressed whole animal oxygen consumption by virtue of defective oxidative metabolism. The data also indicate that the tissue defects are very different in various types of obese animal models. This probably is also true for different types of human obesity.

Animals↗

PubMed1990

The effect of triiodothyronine on glucose utilization in adipocytes from obese rats.

1. In the presence of insulin, 10(-5) M 3,3',5-triiodothyronine (T3) treatment for 1/2 hr decreased fatty acid synthesis 35% only in adipocytes from lean rats, whereas at 10(-11) M through 10(-7) M T3 the obese adipocytes had nearly a 20% increase in fatty acid synthesis. 2. A 2 hr pretreatment of adipocytes with 10(-9) and 10(-7) M T3 decreased insulin-stimulated fatty acid synthesis by nearly 20% in both lean and obese adipocytes. 3. In the absence of insulin, the 2 hr pretreatment with 10(-9) M T3 resulted in a 45% increase in lean adipocyte fatty acid synthesis, though the obese adipocytes required at least 10(-7) M T3 for 2 hr to increase the non-insulin-stimulated fatty acid synthesis by 50%. 4. At 10(-9) M T3 concentrations non-insulin-stimulated fatty acid synthesis was increased by 200% in lean adipose tissue explants, but obese adipose explants were not significantly affected under these conditions. 5. The addition of 10(-9) M T3 plus insulin to the explant media decreased fatty acid synthesis by 35% in both the lean and obese tissues. 6. The results also imply that the low T3 status of the obese rat may be contributory to the elevated fatty acid synthesis observed in obese adipocytes.

Adipose Tissue↗