Muscular hypertrophy of urinary bladders in dominant tilapia facilitates the control of aggression through urinary signals

The urination pattern of the Mozambique tilapia (Oreochromis mossambicus) depends on social context, and the olfactory potency of urine released depends on social rank (males) and reproductive status (females). This strongly suggests that urine mediates chemical communication in this species. The current study tested, firstly, whether urine production rate depends on sex or social status and, secondly, whether differences in urination pattern and volume of urine stored are associated with variation in the morphology of the urinary bladder. Finally, the effect of urination during aggressive male–male interactions was assessed. Urine production in catheterized fish depended neither on sex nor social status (males). Nevertheless, males had larger kidneys than females. Dominant males had heavier urinary bladders than subordinate males or females, mainly due to enlarged muscle fibres, thicker urothelium and a thicker smooth muscle layer. In male pairs wherein urination was prevented by temporary constriction of the genital papillae, social interaction escalated to aggression (mouth-to-mouth fighting) more rapidly and frequently than control pairs. This was accompanied by elevated plasma testosterone and 11-ketotestosterone levels. In control encounters, the male that initiated the aggressive behaviour was usually the winner of the subsequent fight; this did not happen when the males could not urinate. These results suggest that the larger, more muscular bladder of dominant males is an adaptation, facilitating higher urination frequency, post-renal modulation and storage of larger urine volumes for longer. It is likely that urinary pheromones modulate aggression in male–male encounters by providing information on the social rank and/or motivation of the emitter; males are unlikely to invest in costly highly aggressive fights if they judge their opponent to be more dominant. Thus, a morphological explanation for the differing urination patterns of dominant and subordinant males, and females, has been provided, and a possible function for this behaviour in male–male interactions is suggested.

Chronic medical conditions mediate the association between depression and cardiovascular disease mortality

Purpose

To determine whether chronic medical conditions mediate the association between depression and cardiovascular disease (CVD) mortality.

Methods

Data analyzed were from 6,394 subjects aged 25–74 years who participated in extensive health examinations in the NHEFS conducted between 1971 and 1975 and follow-up studies to 1992. CVD mortality was the endpoint. Depression predictors were clinically significant depressive symptoms at baseline by the GWB-D, and/or at 1982–84 by the CES-D (‘baseline’, ‘new’, or ‘twice’ depression). Chronic conditions were prevalent/incident high blood pressure, diabetes, and nonfatal CVD by examination and/or self-report. Mediation effects were assessed by stepwise adjustments of covariates and additive interactions in competing-risks regression models (accounting for other mortality causes) and logit models.

Results

Baseline, new, and twice depression were significant predictors of CVD mortality in competing-risks models adjusted for demographics (HRs 1.3, 1.4, and 2.0), but effects were progressively weakened and became non-significant after adjustment for lifestyle factors, prevalent and incident medical conditions, respectively. CVD mortality risk was 80% higher for depression plus incident nonfatal CVD than without (HR 4.0 vs. 3.2, additive interaction), and mediation effects of depression via chronic medical conditions (particularly via incident nonfatal CVD) increased the risk by 2 to 11% in logit models, independent of all covariates.

Conclusions

Several levels of evidence suggest that the association between depression and CVD mortality is partially mediated by prevalent/incident chronic medical conditions, as well as unhealthy lifestyle behaviors. Patients presenting with clinically significant depressive symptoms, particularly if persistent, should be assessed for both chronic conditions and lifestyle risk factors.

Sex-specific Long-term Behavioral and Neuroendocrine Consequences Oftransient Peripubertal Metabolic Challenges

Interaction between neuroendocrine stress and metabolic signals has become increasingly linked to the pathogenesis of affective and cognitive disorders. Independent evidence shows that nuclear receptors represent an essential interface of communication between these signals and the central nervous system.

On the premise that lifelong brain functions are subject to programming by stressful and metabolic signals during early life, we induced voluntary hyperphagia in prepubertal male and female rats by providing them with a cafeteria-like choice between normal chow and foods with high motivational value (palatable, high fat/high energy). The cafeteria diet was withdrawn from one subset of animals during early adulthood (postnatal day, PND 80), and several endpoints of interest were monitored until PND 200. While both sexes displayed similar metabolic outcomes during exposure to the cafeteria diet, there were substantial sex differences in the metabolic, behavioral and endocrine consequences of withdrawal of palatable food. Consistently increased food consumption and body mass gain were recorded in males, whereas females that were pre-exposed to the cafeteria diet showed clear signs of adrenocortical hyperactivity. Thus, besides verification of sex-specific mal-programming of appetitive behavior and metabolic set-points by early life events, we also demonstrate evidence for differential translation of metabolic challenges during peripubertal development into aberrations suggestive of altered neuroendocrine responsiveness to stress.

Total oxidant scavenging capacity of Euterpe oleracea Mart. (açaí) seeds and identification of their polyphenolic compounds

The antioxidant capacity of methanol and ethanol seed extracts from Euterpe oleracea Mart. (açaí) against the reactive oxygen species (ROS) peroxyl radicals, peroxynitrite, and hydroxyl radicals was studied with the total oxidant scavenging capacity (TOSC) assay in a modified and automated version. Cold methanol digestion was the most efficient extraction method with respect to the antioxidant capacity. The extracts exhibit good antioxidant capacity against peroxyl radicals, similar to the capacity of the pulp. The antioxidant capacity against peroxynitrite and hydroxyl radicals is even higher. The main antioxidants identified by HPLC-MS and HPLC-CEAD are five different procyanidins (di- through pentamers); furthermore, protocatechuic acid and epicatechin were identified as minor compounds. Determination of TOSC values of HPLC seed extract fractions indicates that the procyanidins contribute substantially to the overall antioxidant capacity. In addition, however, other compounds that have not yet been identified are responsible for a large part of the observed antioxidant capacity.

Brain and ocular metastases from a transmissible venereal tumour in a dog

A five-year-old crossbred dog was referred with rapidly growing masses over its penis and right popliteal lymph node. The dog had severe blepharospasm, congestion of episcleral vessels and rubeosis iridis of the left eye. A presumptive diagnosis of transmissible venereal tumour (TVT) and iridocyclitis was made based on the results of fine needle aspiration. Chemotherapy with vincristine and prednisolone was initiated and after four months the dog made a complete recovery. However, the dog subsequently relapsed, showing miosis, blepharospasm and a well defined mass within the anterior chamber of the left eye. In addition, the dog exhibited generalised 'grand mal' type seizures. Computed tomographic (CT) examination of the brain revealed two distinct masses in the left frontal lobe. Because of the poor prognosis, the owners elected to have the dog euthanased. On histopathology, metastases of TVT in the left eye and left cerebral hemisphere were found, showing no specific staining for CD3, immunoglobulin (Ig) G, IgM and lambda light chains. It was therefore concluded that the tumour growth was progressive, and that there was an absence of local humoral immune response against TVT in this case.

Clear-cell sarcoma of tendons and aponeuroses studied by immunoscintigraphy

Clear-cell sarcoma is a rare tumor that arises in association with tendons and aponeuroses. Although it shares with malignant melanoma several histologic and ultrastructural features, it has a clinical course different from that of conventional melanomas. A case of clear-cell sarcoma studied by immunoscintigraphy with 99mTc-labeled F(ab')2 fragments of the monoclonal antibody 225.28 S is reported.

White matter signal hyperintensities in the brains of patients with late paraphrenia and the normal, community-living elderly

We determined the prevalence and anatomical location of areas of white matter hyperintensity visualized by magnetic resonance imaging in the brains of 38 late paraphrenic patients with an onset of psychotic illness after the age of 60 and 31 healthy aged community volunteers. All degrees of white matter signal hyperintensity were very common in both groups, and there was no excess of such changes in the brain of patients. Periventricular white matter and subcortical grey matter hyperintensities were significantly associated with both measured diastolic and systolic blood pressure in patients and control subjects. Periventricular and deep white matter, together with subcortical grey matter hyperintensities, were significantly associated with increased age. The excess of such presumed brain-imaging abnormalities previously reported in patients with an onset of psychosis late in life may be a consequence of earlier authors' failure to include examination of appropriate community control populations and to carefully exclude patients with evidence of stroke.

Magnetic resonance imaging volumetric measurements of the superior temporal gyrus, hippocampus, parahippocampal gyrus, frontal and temporal lobes in late paraphrenia

Quantified magnetic resonance measurements were made of superior temporal gyrus, parahippocampal gyrus, hippocampal, frontal and temporal lobe volumes and of the planar area of the thalamus and basal ganglia structures in 47 late paraphrenic patients and 33 healthy elderly controls. The late paraphrenics were divided into 31 schizophrenics and 16 patients with delusional disorder according to ICD-10 guidelines. Patients with delusional disorder tended to have smaller left temporal volumes compared with control subjects and patients with schizophrenia, but this difference failed to reach accepted levels of statistical significance after correction for the effects of multiple statistical comparisons, age and total brain size. Physiological right-left asymmetry, reported for temporal and frontal lobe volumes, was present in control, schizophrenic and delusional disorder subjects but delusional disorder patients had a significantly greater degree of temporal lobe asymmetry. The results add to the evidence for heterogeneity among late-onset psychoses and emphasize the subtle nature of any structural brain abnormalities in these patients.

Quantitative magnetic resonance imaging volumetry distinguishes delusional disorder from late-onset schizophrenia

BACKGROUND

Late paraphrenia is recognised as a heterogeneous disorder. This is reflected by the division of such patients into schizophrenia and delusional disorder in ICD-10. Earlier imaging studies have suggested that major structural abnormalities may be associated with the onset of psychosis in later life.

METHOD

Fifty late paraphrenics and 35 age-matched healthy controls underwent structural magnetic resonance imaging of the whole brain in the coronal plane. Measurements were made of intracranial and brain volumes and the volumes of the intracerebral and extracerebral cerebrospinal fluid spaces.

RESULTS

No differences in intracranial, brain or extracerebral cerebrospinal fluid volumes between patients and controls were found. Late paraphrenic patients had greater lateral and third ventricle volumes than controls and the left lateral ventricle was larger than the right. When the patients were divided into appropriate ICD-10 diagnoses: paranoid schizophrenia (n = 31) and delusional disorder (n = 16), lateral ventricle volumes in the delusional disorder patients were much greater than those of the schizophrenics and almost twice those of controls.

CONCLUSIONS

Structural brain differences underly diagnostic heterogeneity within late paraphrenia. The brains of late onset schizophrenics are only subtly different from those of healthy elderly individuals.

Phenomenology, demography and diagnosis in late paraphrenia

One hundred and one patients with late paraphrenia were examined using the Present State Examination. The established high prevalence rates of female gender, the unmarried state and sensory impairment were confirmed. All of the symptoms of schizophrenia, with the exception of formal thought disorder, were found in the subjects with approximately the same prevalence as reported in schizophrenics with a symptom onset in younger life. The presence of visual hallucinosis was significantly associated with visual impairment, but the same association was not found between auditory hallucinations and deafness. Mean age at onset of symptoms was high at 74.1 years. Using ICD-10 diagnostic criteria the patients were categorized as schizophrenia (61.4%), delusional disorder (30.7%) and schizoaffective disorder (7.9%). Patients in these diagnostic categories differed in their pre-morbid IQ estimations, current cognitive state measured by the Mini-Mental State Examination and in the number of scored positive psychotic PSE symptoms and their systematization of and preoccupation with delusions and hallucinations. There were no significant differences between the patients in the ICD-10 schizophrenia and delusional disorder groups in terms of age at symptom onset, sex ratio, response to treatment, being unmarried, the presence of insight or sensory impairment. The high degree of clinical similarity between patients with late paraphrenia combined with the inability of ICD-10 to define diagnostic subgroups that correspond to patient clusters derived from clinical symptoms or which are meaningfully different from each other in terms of demographic and prognostic factors provide a strong argument for the retention of late paraphrenia as the most appropriate diagnosis for such patients.

Schizophrenic symptoms in late paraphrenia

The prevalence of most individual schizophrenic symptoms in late paraphrenia is unknown. Previous attempts to characterize the symptoms of late paraphrenia have been retrospective case-note studies, have not used standardized assessment instruments or have only examined small populations of patients. We examined 83 late paraphrenic patients using the Present State Examination. Persecutory delusions occurred in 86.7% of patients and were the most common symptom elicited. Nonverbal (63.8%) and verbal third person (50.6%) auditory hallucinations were common, as were visual hallucinations (30.1%). Earlier authors have claimed that thought insertion and thought withdrawal do not occur in late paraphrenia; we found them in 15.7 and 6.0%, respectively, of our patients.

The assessment of insight in psychosis

An assessment schedule was used to determine the nature of insight in 91 mixed psychotic patients, and to examine its distribution and associations. While all the components of the schedule intercorrelated significantly, scores for compliance were only weakly related to those for ability to label psychotic phenomena as abnormal. Compliance and illness recognition were related to IQ. Total insight score was inversely correlated, moderately, with a global measure of psychopathology derived from the PSE, and was less in patients involuntarily committed. Age, sex, diagnosis, and the number of previous hospital admissions had little effect. The results support the notion that insight is not a unitary concept.

Relapsing polychondritis and Reiter's syndrome

We describe a case of relapsing polychondritis associated with Reiter's Syndrome in a 46-year-old white man. Relapsing polychondritis is a rare disorder of unknown etiology associated in about 30% of cases with other rheumatic disorders such as connective tissue diseases, vasculitis and exceptionally, seronegative spondyloarthritis. We found this association only once in our review of the literature.

[Paraphrenia in the elderly. Psychopathologic and computer tomography indications of two subtypes]

Psychopathological and cranial computed tomography findings in 48 patients with late paraphrenia were compared with the findings in 40 normal controls. 19 patients with late paraphrenia and first rank symptoms showed significantly less cortical atrophy than 29 patients without first rank symptoms (p less than 0.01). There were no significant differences of ventricular enlargement, cerebellar atrophy, the presence of leukoaraiosis or basal ganglia mineralisation between the late paraphrenic and control groups. In contrast to the controls, cortical atrophy, ventricular enlargement and the presence of leukoaraiosis were not age-related. These results may indicate different origins of late paraphrenia with or without first rank symptoms.

Intermittent fetal bradycardia induced by midpregnancy fetal ultrasonographic study

Fetal bradycardias were observed during fetal ultrasonographic and echocardiographic studies performed in the second trimester of pregnancy. The episodes of bradycardia were brief and recovery was usually rapid. Ultrasound transducer pressure applied to the maternal abdomen during the study provoked the phenomenon. Vagal discharge resulting from an increase in intrauterine pressure appeared to be the causative mechanism.