Biomedical subjects

L Marino

Publications and source records attributed to L Marino.

At least 19 recordsLinked to original sources

PubMed2005

Risk factors for type 2 diabetes in women attending menopause clinics in Italy: a cross-sectional study.

OBJECTIVE: To analyze risk factors for type 2 diabetes among women attending menopause clinics in Italy for counselling about the menopause. SUBJECTS: Women attending a network of first-level outpatient menopause clinics in Italy for general counselling about menopause or treatment of menopausal symptoms. METHODS: Cross-sectional study with no exclusion criteria. Type 2 diabetes was defined according to National Diabetes Data Groups Indications and the fasting blood glucose at an oral glucose tolerance test within the previous year. RESULTS: Out of the 44 694 considered in this analysis, 808 had a diagnosis of diabetes type 2 (1.8%). In comparison with women aged < 50 years, the multivariate odds ratios (OR) of type 2 diabetes were 1.31 (95% confidence interval (CI), 0.99-1.74) for women aged 50-52 years, 1.66 (95% CI, 1.27-2.17) at 53-56 years and 2.84 (95% CI, 2.20-3.67) in women aged > or = 57 years. Type 2 diabetes was less frequently reported in more educated women (OR high school/university vs. primary school = 0.44 (95% CI, 0.36-0.55)). Being overweight was associated with an increased risk of type 2 diabetes. In comparison with women reporting a low level of physical activity, the multivariate OR of type 2 diabetes was 0.67 (95% CI, 0.54-0.84) for women reporting regular physical activity. In comparison with premenopausal women, the multivariate OR of type 2 diabetes was 1.38 (95% CI, 1.03-1.84) in women with natural menopause. This finding was present also after allowing for the potential confounding effect of age. The multivariate OR of diabetes for users of hormonal replacement therapy was 0.58 (95% CI, 0.46-0.73). CONCLUSIONS: This large cross-sectional study suggests that postmenopausal women are at higher risk of type 2 diabetes after allowance for the effect of age. Other main determinants of risk of type 2 diabetes in women around menopause were low socioeconomic status and being overweight. Diabetes was found less frequently in those taking hormone replacement therapy.

Age Distribution↗

PubMed2003

Magnetic resonance images of the brain of a dwarf sperm whale (Kogia simus).

Cetacean (dolphin, whale and porpoise) brains are among the least studied mammalian brains because of the difficulty of collecting and histologically preparing such relatively rare and large specimens. Among cetaceans, there exist relatively few studies of the brain of the dwarf sperm whale (Kogia simus). Magnetic resonance imaging (MRI) offers a means of observing the internal structure of the brain when traditional histological procedures are not practical. Therefore, MRI has become a critical tool in the study of the brain of cetaceans and other large species. This paper represents the first MRI-based anatomically labelled three-dimensional description of the dwarf sperm whale brain. Coronal plane sections of the brain of a sub-adult dwarf sperm whale were originally acquired and used to produce virtual digital scans in the other two orthogonal spatial planes. A sequential set of images in all three planes has been anatomically labelled and displays the proportions and positions of major neuroanatomical features.

Animals↗

PubMed2002

Description of a poorly differentiated carcinoma within the brainstem of a white whale (Delphinapterus leucas) from magnetic resonance images and histological analysis.

In this study we used magnetic resonance imaging (MRI) to investigate neuroanatomical structure in the brain of a white whale (Delphinapterus leucas) that died from a large tumor within the brainstem. This specimen was also compared with a normal white whale brain using MRI. MRI scans of the white whale specimen show how the tumor deformed surrounding brain structure. Histopathological analysis indicated a poorly differentiated carcinoma of uncertain origin. These analyses demonstrate the usefulness of supplementing histological analyses of pathology with studies of gross morphology facilitated by MRI.

Animals↗

PubMed2001

Anatomy and three-dimensional reconstructions of the brain of a bottlenose dolphin (Tursiops truncatus) from magnetic resonance images.

Cetacean (dolphin, whale, and porpoise) brains are among the least studied mammalian brains because of the formidable challenge of collecting and histologically preparing such relatively rare and large specimens. Magnetic resonance imaging offers a means of observing the internal structure of the brain when traditional histological procedures are not practical. Furthermore, internal structures can be analyzed in their precise anatomic positions, which is difficult to accomplish after the spatial distortions often accompanying histological processing. In this study, images of the brain of an adult bottlenose dolphin, Tursiops truncatus, were scanned in the coronal plane at 148 antero-posterior levels. From these scans a computer-generated three-dimensional model was constructed using the programs VoxelView and VoxelMath (Vital Images, Inc.). This model, wherein details of internal and external morphology are represented in three-dimensional space, was then resectioned in orthogonal planes to produce corresponding series of virtual sections in the horizontal and sagittal planes. Sections in all three planes display the sizes and positions of major neuroanatomical features such as the arrangement of cortical lobes and subcortical structures such as the inferior and superior colliculi, and demonstrate the utility of MRI for neuroanatomical investigations of dolphin brains.

Anatomy, Cross-Sectional↗

PubMed2001

Mirror self-recognition in the bottlenose dolphin: a case of cognitive convergence.

The ability to recognize oneself in a mirror is an exceedingly rare capacity in the animal kingdom. To date, only humans and great apes have shown convincing evidence of mirror self-recognition. Two dolphins were exposed to reflective surfaces, and both demonstrated responses consistent with the use of the mirror to investigate marked parts of the body. This ability to use a mirror to inspect parts of the body is a striking example of evolutionary convergence with great apes and humans.

Animals↗

PubMed2001

Anatomy and three-dimensional reconstructions of the brain of the white whale (Delphinapterus leucas) from magnetic resonance images.

Magnetic resonance imaging offers a means of observing the internal structure of the brain where traditional procedures of embedding, sectioning, staining, mounting, and microscopic examination of thousands of sections are not practical. Furthermore, internal structures can be analyzed in their precise quantitative spatial interrelationships, which is difficult to accomplish after the spatial distortions often accompanying histological processing. For these reasons, magnetic resonance imaging makes specimens that were traditionally difficult to analyze, more accessible. In the present study, images of the brain of a white whale (Beluga) Delphinapterus leucas were scanned in the coronal plane at 119 antero-posterior levels. From these scans, a computer-generated three-dimensional model was constructed using the programs VoxelView and VoxelMath (Vital Images, Inc.). This model, wherein details of internal and external morphology are represented in three-dimensional space, was then resectioned in orthogonal planes to produce corresponding series of "virtual" sections in the horizontal and sagittal planes. Sections in all three planes display the sizes and positions of such structures as the corpus callosum, internal capsule, cerebral peduncles, cerebral ventricles, certain thalamic nuclear groups, caudate nucleus, ventral striatum, pontine nuclei, cerebellar cortex and white matter, and all cerebral cortical sulci and gyri.

Animals↗

PubMed2001

Erectile and endothelial dysfunction in Type II diabetes: a possible link.

AIMS/HYPOTHESIS: The aim of this study was to evaluate the relation between erectile dysfunction and endothelial functions, coagulation activation, peripheral and autonomic neuropathy in men with Type II (non-insulin-dependent) diabetes mellitus. METHODS: We studied 30 Type II diabetic patients with symptomatic erectile dysfunction and 30 potent diabetic patients matched for age and disease. Endothelial functions were assessed with the L-arginine test, plasma thrombomodulin and cell adhesion molecules circulating concentrations. Haemostasis was evaluated with markers of thrombin activation and fibrinolysis. Quantitative sensory testing (vibratory, warming, and heat-pain thresholds), cardiovascular reflex tests and 24-h blood pressure monitoring were used to assess peripheral or autonomic neuropathy. RESULTS: Mean erectile score and HbA1c were 10.5+/-5.8 and 8.3+/-1.6% in patients with erectile dysfunction, and 24.0+/-0.7 and 6.8+/-1.4% in those without erectile dysfunction, respectively (p < 0.001); there was a significant relation between HbA1c and erectile function score in patients with erectile dysfunction (r = -0.45, p = 0.02). The decrease in blood pressure and platelet aggregation in response to L-arginine was lower (p < 0.05-0.02) in patients with erectile dysfunction, whereas soluble thrombomodulin, P-selectin and intercellular cell ahhesion molecule-1 concentrations were higher (p < 0.05-0.02). Indices of coagulation activation (F1 + 2 and D-dimers) and reduced fibrinolysis (PAI-1) were also found to be higher in erectile dysfunction patients. Heat-pain and warm perception thresholds. as well as cardiovascular reflex tests, were most commonly abnormal in patients with erectile dysfunction (p < 0.05). In multivariate analysis, HbA1c, MBP response to L-arginine, P-selectin, indices of coagulation, and quantitative sensory testing were independent predictors of erectile function score. CONCLUSION/INTERPRETATION: Erectile dysfunction in diabetic men correlates with endothelial dysfunction. A reduced nitric oxide activity might provide a unifying explanation.

Arginine↗

PubMed2001

Magnetic resonance imaging and three-dimensional reconstructions of the brain of a fetal common dolphin, Delphinus delphis.

To demonstrate the kinds of data that can be obtained non-destructively and non-invasively from preserved museum specimens using modern imaging technology the head region of a whole body fetal specimen of the common dolphin, Delphinus delphis, aged 8-9 months post-conception, was scanned using Magnetic Resonance Imaging (MRI). Series of scans were obtained in coronal, sagittal and horizontal planes. A digital three-dimensional reconstruction of the whole brain was prepared from the coronal series of scans. Sectional areas and three-dimensional volumes were obtained of the cerebral hemispheres and of the brainstem-plus-cerebellum. Neuroanatomical features identified in the scans include the major sulci of the cerebral hemispheres, well-differentiated regions of gray and white matter, the mesencephalic, pontine, and cervical flexures, the "foreshortened" appearance of the forebrain, and the large auditory inferior colliculi. These findings show that numerous features of the fetal common dolphin brain can be visualized and analyzed from MRI scans.

Animals↗

PubMed2000

Asymmetries in cerebral width in nonhuman primate brains as revealed by magnetic resonance imaging (MRI).

A comparative study of asymmetries in cerebral width was conducted in a sample of great apes, Old World and New World monkeys. The brains of all subjects were scanned using magnetic resonance imaging (MRI) and the first axial slice above the third ventricle was identified. Measures of cerebral width were taken at distances of 10% and 30% of the length from the occipital and frontal poles. Cerebral widths were measured from the midline to the lateral surface of the brain for each area. The great apes exhibited a right-frontal and left-occipital directional asymmetry in cerebral width. In contrast, no significant mean directional asymmetries were found in either the Old or New World monkeys. The results in the great apes are consistent with previous reports of petalia asymmetries and suggest that the use of MRI is a valid approach to the assessment of neuroanatomical asymmetries in primates.

Animals↗

PubMed2000

Bubble ring play of bottlenose dolphins (Tursiops truncatus): implications for cognition.

Research on the cognitive capacities of dolphins and other cetaceans (whales and porpoises) has importance for the study of comparative cognition, particularly with other large-brained social mammals, such as primates. One of the areas in which cetaceans can be compared with primates is that of object manipulation and physical causality, for which there is an abundant body of literature in primates. The authors supplemented qualitative observations with statistical methods to examine playful bouts of underwater bubble ring production and manipulation in 4 juvenile male captive bottlenose dolphins (Tursiops truncatus). The results are consistent with the hypothesis that dolphins monitor the quality of their bubble rings and anticipate their actions during bubble ring play.

Animals↗

PubMed2000

Relative volume of the cerebellum in dolphins and comparison with anthropoid primates.

According to the 'developmental constraint hypothesis' of comparative mammalian neuroanatomy, brain growth follows predictable allometric trends. Therefore, brain structures should scale to the entire brain in the same way across mammals. Evidence for a departure from this pattern for cerebellum volume has recently been reported among the anthropoid primates. One of the mammalian groups that has been neglected in tests of the 'developmental constraint hypothesis' is the cetaceans (dolphins, whales, and porpoises). Because many cetaceans possess relative brain sizes in the range of primates comparative tests of the 'developmental constraint hypothesis' across these two groups could help to delineate the parameters of this hypothesis. In this paper, we compare relative cerebellum volumes in two cetacean species, the bottlenose dolphin (Tursiops truncatus) and the common dolphin (Delphinus delphis), with published data from anthropoid primates. We found that relative cerebellum size is significantly greater in the two dolphin species than in any of the primates, including humans. These results suggest that there is possibly expansion of brain structures independent of strictly allometric processes.

Animals↗

PubMed1999

Essentialism revisited: evolutionary theory and the concept of mental disorder.

J. C. Wakefield's (1999) elaboration of his harmful dysfunction analysis (HDA) of mental disorder does little to address previous criticisms (S. O. Lilienfeld & L. Marino, 1995) and instead reveals further conceptual weaknesses in his position. The authors demonstrate that (a) a Roschian analysis can account for the results of all of Wakefield's conceptual experiments and predicts a number of judgments of disorder not predicted by the HDA, (b) the HDA is incapable in many cases of providing a scientifically nonarbitrary distinction between disorder and nondisorder, and (c) the HDA cannot account for failures of cultural ex adaptations, mismatches between evolutionary design and novel environments, or defenses against threat. The authors argue that the HDA has been convincingly falsified and discuss the failure of essentialistic concepts to resolve controversies in other domains of biological science.

Biological Evolution↗

PubMed1999

A preliminary investigation of the construct of psychopathic personality (psychopathy) in chimpanzees (Pan troglodytes).

Although the construct of psychopathy has received considerable attention in humans, its relevance to other animals is largely unknown. We developed a measure of psychopathy for use in chimpanzees (Pan troglodytes), the Chimpanzee Psychopathy Measure (CPM), and asked 6 raters to complete this index on 34 chimpanzees. The CPM (a) demonstrated satisfactory interrater reliability and internal consistency; (b) exhibited marginally significant sex differences (males > females); (c) correlated positively with measures of extraversion, agreeableness, and observational ratings of agonism, sexual activity, daring behaviors, teasing, silent bluff displays, and temper tantrums, and negatively with observational ratings of generosity; and (d) demonstrated incremental validity above and beyond a measure of dominance. Although further validation of the CPM is needed, these findings suggest that the psychopathy construct may be relevant to chimpanzees.

Age Factors↗

PubMed1999

Identification and characterization of IS2404 and IS2606: two distinct repeated sequences for detection of Mycobacterium ulcerans by PCR.

Molecular analysis of Mycobacterium ulcerans has revealed two new insertion sequences (ISs), IS2404 and IS2606. IS2404 was identified by complete sequencing of a previously described repetitive DNA segment from M. ulcerans. This element is 1,274 bp long, contains 12-bp inverted repeats and a single open reading frame (ORF) potentially encoding a protein of 327 amino acids (aa), and apparently generates 7-bp direct repeats upon transposition. Amino acid similarity was found between the putative transposase and those encoded by ISs in other bacterial sequences from Aeromonas salmonicida (AsIs1), Escherichia coli (H repeat element), Vibrio cholerae (VcIS1), and Porphyromonas gingivalis (PGIS2). The second IS, IS2606, was discovered by sequence analysis of a HaeIII fragment of M. ulcerans genomic DNA containing a repetitive sequence. This element is 1,404 bp long, with 12-bp inverted repeats and a single ORF potentially encoding a protein of 445 aa. Database searches revealed a high degree of amino acid identity (70%) with the putative transposase of IS1554 from M. tuberculosis. Significant amino acid identity (40%) was also observed with transposases from several other microorganisms, including Rhizobium meliloti (ISRm3), Burkholderia cepacia (IS1356), Corynebacterium diphtheriae, and Yersinia pestis. PCR screening of DNA from 45 other species of mycobacteria with primers for IS2404 confirm that this element is found only in M. ulcerans. However, by PCR, IS2606 was also found in Mycobacterium lentiflavum, another slow-growing member of the genus Mycobacterium that is apparently genetically distinct from M. ulcerans. Testing the sensitivity of PCR based on IS2404 and IS2606 primers demonstrated the ability to detect 0.1 and 1 M. ulcerans genome equivalents, respectively. The ability to detect small numbers of cells by using two gene targets will be particularly useful for analyzing environmental samples, where there may be low concentrations of M. ulcerans among large numbers of other environmental mycobacteria.

Base Sequence↗

PubMed1999

Seroprevalence of hepatitis C in a sample of middle class substance abusers.

Hepatitis C (HCV) is an indolent and often fatal disease affecting four million Americans commonly associated with low socioeconomic status. We assessed its prevalence in a sample of 334 consecutively admitted middle class substance abusers in a private urban hospital, and ascertained risk factors for its transmission. We found that the point prevalence rate for HCV was 27.7% among all substance abusers, and 76.7% among intravenous drug users. Using logistic regression, we found risk factors associated with HCV were intravenous drug use, needle sharing, prior liver disease, opioid dependence, HIV infection, and benzodiazepine dependence. Not found to increase infective risk were lower social class, male gender, African-American race, male homosexuality, unemployment, and the absence of private health insurance. Multiple viral genotype types were identified in this sample, suggesting diverse sources of transmission in the sample. This study documents an epidemic of HCV in an American middle class sample.

Adult↗

PubMed1998

Planum temporale asymmetries in great apes as revealed by magnetic resonance imaging (MRI).

The planum temporale (PT), a portion of Wernicke's area, is important for linguistic functions in humans and is larger in the left compared to the right hemisphere. In this study, we assessed the presence and size of the PT in a sample of non-human primates including 21 great apes, four lesser apes, 11 Old World monkeys and eight New World monkeys using magnetic resonance imaging. The PT was measured in both the sagittal and coronal planes by use of multiplanar reformatting software. The PT could only be identified in the sample of great apes and not in the remaining non-human primate species. Within the great ape sample, the PT was larger in the left hemisphere than in the right in a statistical majority of the subjects. These results are consistent with the notion that the PT evolved as a definable structure about 15 million years ago and may have arisen as a result for selection for greater cortical folding which in turn led to greater gyrification in larger brains.

Animals↗

PubMed1998

Altered surface myoelectric signals in peripheral vascular disease: correlations with muscle fiber composition.

Conduction velocity (CV) and median frequency (MDF) during tetanic electrical stimulation of the tibialis anterior muscle were evaluated in patients with uncomplicated peripheral arterial occlusive disease. Results were analyzed with respect to biopsy determination of diameter and proportion of types 1 and 2 muscles fibers. Initial MDF and CV correlated positively with type 2, but not type 1 fiber diameter. Initial MDF was reduced bilaterally in patients with unilateral peripheral arterial occlusive disease as compared to normal subjects, indicating that chronic ischemia alone cannot explain the altered myoelectric signal. Physical training increased pain-free walking distance and raised initial MDF, though CV remained unchanged. Fatigue indices were highly interrelated, but showed no correlation with any of the other evaluation variables. Thus, initial MDF, a correlate of type 2 muscle fiber distribution in chronically ischemic tibialis anterior muscles, is altered in peripheral vascular disease. However, muscle ischemia alone cannot explain all aspects of this abnormality.

Aged↗

PubMed1998

A comparison of encephalization between odontocete cetaceans and anthropoid primates.

There have been very few studies of brain size and encephalization in cetaceans and essentially none that have made direct quantitative comparisons of cetaceans and another mammalian group using large normative samples. In the present study two different measures of encephalization were calculated and used to rank and compare 21 odontocete species and 60 anthropoid primate species. Comparisons were made both within and between the two groups. Results show that the encephalization level of Homo sapiens is still extraordinary relative to that of nonhuman species. Nevertheless, a subset of delphinid odontocetes are significantly more highly encephalized than the most highly encephalized anthropoid primates and narrow the gap in encephalization between humans and nonhumans substantially. These findings may have implications for comparative models of the relative importance of brain size versus brain organization for the evolution of intelligence.

Animals↗