Suicidal ideation among single, pregnant adolescents: The role of sexual and religious knowledge, attitudes and practices.

Pregnant adolescents are a high-risk population for suicide. However, a knowledge gap still exists on how sexual and religious knowledge, attitudes and practices (KAP) influence suicidal ideation (SI) in teenage pregnancy. We aim to explore the interplay between psychiatric diagnoses, sociodemographic factors and KAP of sexual and religious issues as risk factors of SI among 114 pregnant Malaysian adolescents from 6 rehabilitation centers and a tertiary hospital. Single sexual partner was an independent predictor of SI, suggesting the role of less sexual experience as a risk factor for SI after controlling for major depression. Participants who were unsure versus those who agreed with the statement that most religions' viewed sex outside marriage as wrong had a lower risk of SI after controlling for major depression. Pregnant adolescents with a single sexual partner were significantly associated with current SI. Ambivalence towards religious prohibitions on premarital sex may protect against suicidal ideation.

Intracellular and extracellular spaces of normal adult rat brain determined from the proton nuclear magnetic resonance relaxation times.

The nuclear magnetic resonance method was used to investigate the state of water molecules in normal rat brain tissue in vitro. The transverse magnetization decay curve (TMDC) of the fresh brain tissue of adult rats (8- or 10-weeks-old) was biexponential, which could be interpreted in terms of two distinct transverse relaxation times (T2). Several factors that may affect the TMDC are discussed. It was concluded that the fast and slow components of T2 correspond to those of the water molecules of the intracellular and the extracellular spaces of normal rat brain tissue, respectively.

Sequential changes in MR water proton relaxation time detect the process of rat brain myelination during maturation.

For better understanding of the behavior of water molecules in the animal brain, changes in magnetic resonance water proton relaxation processes were studied in the rat during maturation. Midbrains of male Wistar rats were removed at various time points ranging from 2 to 70 days after birth. Changes in relaxation time (water proton longitudinal relaxation time by the inversion recovery, and water proton transverse relaxation time by the spin echo and the Carr-Purcell-Meiboom-Gill pulse sequence (CPMG)) and water content were then determined for various stages of brain development. During maturation both water proton longitudinal relaxation time and water proton transverse relaxation time values decreased and this finding paralleled the decline in water content. Using the CPMG pulse sequence, the transverse relaxation time values were observed to separate into two components after 21 days. Morphologically, the most prominent change at the matured stage of midbrain development in the rat is myelination. Water proton relaxation time, which can be estimated using the CPMG pulse sequence, showed a close correlation with myelination in the central nervous system.

Three-dimensional redox image of the normal gerbil brain.

Regional differences in the redox ratio were studied in the gerbil brain. Brains were frozen using an in situ funnel-freezing method, and sliced coronally for scanning of mitochondrial redox imaging. The relative local redox ratio of nicotinamide-adenosine dinucleotide to its reduced form was calculated from fluorescence signals of intrinsic fluorochromes, i.e. reduced nicotinamide-adenosine dinucleotide and flavoproteins, using a high resolution fluorometer developed in our laboratory. Twelve consecutive coronal images were obtained from each of 10 gerbils. The mean value of the regional redox ratio in both the cerebral and cerebellar gray matter were found to be significantly lower than that in the cerebral and cerebellar white matter (P < 0.01, Mann-Whitney test). Local differences in the redox ratio were also found among subregions of gray matter. The redox ratio in the globus pallidus was significantly higher than values in other subregions of gray matter (P < 0.01, Mann-Whitney test) We postulate that a high concentration of the reduced form of pyridine nucleotide is maintained to provide redox energy for rapid turnover of ATP in the areas of high energy consumption.

Early damage to lung tissue after irradiation detected by the magnetic resonance T2 relaxation time.

We sought to determine whether nuclear magnetic resonance relaxation times of water in tissue would be useful to detect molecular damage in lung tissue within 2 weeks after irradiation. Tissue samples were obtained from the lungs of rats at various times between 1 and 14 days after exposure of a hemithorax to 20 Gy 60Co gamma irradiation. The spin-lattice relaxation time, T1, was measured by the inversion recovery method, and the spin-spin relaxation time, T2, was measured by both the Hahn spin-echo (Hahn T2) and the Carr-Purcell-Meiboom-Gill (CPMG T2) methods. The T2 of lung tissue could be divided into two components, T2 fast (T2f) and T2 slow (T2s), which reflected changes in the intracellular and extracellular water, respectively. The CPMG T2f increased significantly 3 days after irradiation (66.3 +/- 2.3 ms compared to 60.8 +/- 2.6 ms), and the CPMG T2s increased significantly 1 day after irradiation (155 +/- 11 ms compared to 138 +/- 7 ms), prior to the observation of abnormalities upon examination of the lung by light microscopy. The CPMG T2 values increased further up to 14 days after irradiation when significant increases were observed in values for T1, Hahn T2 and water content. Our results indicate that the molecular derangement in irradiated lung tissue was detected by the CPMG T2 measurement in the very early stage, and that MRI may be superior to conventional radiographs for detecting the early damage to lung tissue after irradiation.

Magnetic resonance imaging and 11C-N-methylspiperone/positron emission tomography studies in a patient with the interval form of carbon monoxide poisoning.

Magnetic resonance (MR) and (11)C-N-methylspiperone ((11)C-NMSP)/positron emission tomography (PET) imagings were repeatedly performed in a 50-year-old man with the interval form of carbon monoxide (CO) poisoning. In MR images obtained when delayed neuropsychiatric symptoms developed (two months after poisoning), the inner segments of the bilateral globus pallidus appeared as high signal intensities in the T1-weighted and low signal intensities in the T2-weighted images, suggesting prior focal hemorrhage in these areas. A PET study with (11)C-NMSP performed at that time showed an increase in dopamine D2 receptor binding in the caudate and putamen. Treatment with bromocriptine was very effective and five months after the poisoning, MR and (11)C-NMSP/PET images showed improvement, concomitantly with the disappearance of the neuropsychiatric symptoms.

Effects of age on muscle energy metabolism and oxygenation in the forearm muscles.

PURPOSE: The effects of aging on muscle metabolism and oxygenation have not yet been elucidated. We evaluated the effects of aging on energy metabolism and oxygenation in sedentary healthy subjects by simultaneously measuring 31P-magnetic resonance spectroscopy (MRS) and near-infrared spectroscopy (NIRS). METHODS: Nine young (28.1 +/- 5.0 yr) and nine older (61.4 +/- 4.6 yr) healthy subjects were studied. The 31P-MR spectrum was obtained every 15 s during and after hand gripping exercise. Intracellular pH (pHi) and PCr/(PCr+Pi) [PCr: phosphocreatine, Pi: inorganic phosphate] were calculated as an index of energy metabolism. The time constant of the PCr/(PCr+Pi) recovery (tau PCr) was calculated. With NIRS, we evaluated the recovery rates of oxygenated (RHbO2) and deoxygenated hemoglobin (RHb) during the initial 10 s of recovery. RESULTS: The PCr/(PCr+Pi) and pHi at rest and at completion of the exercise and tau PCr did not differ between young and older subjects. However, RHbO2 and RHb were significantly slower in older subjects than in young subjects. CONCLUSIONS: The results suggest that muscle energy metabolism in the forearm muscle was not affected by aging. The slower RHbO2 and RHb in older subjects suggested impaired O2 supply, which was probably due to impaired peripheral circulation caused by the process of aging.

Tissue characterization of pneumonia and irradiated rat lungs with magnetic resonance relaxation times.

To interpret the MRI signal intensities, the T1 and T2 values were determined in vitro for rat lungs with radiation pneumonitis, fibrosis or pneumonia, and also for muscle and fat tissues. The transverse magnetization decays mentioned above exhibited two components, a T2 fast (T2f) and a T2 slow (T2s) component. Lungs from rats with pneumonia had significantly longer T2f and T2s values than lungs from rats with radiation pneumonitis and fibrosis. The T2f and T2s values for a "pneumonia lung" were not significantly different from those of muscle. The measured values of T2f and T2s suggested that radiation pneumonitis and fibrosis likely exhibit lower signal intensities than do muscle and that a "pneumonia lung" likely exhibits a similar signal intensity to that of muscle on T2-weighted MR images.

Implication of ESR signals from ceruloplasmin (Cu(2+)) and transferrin (Fe(3+)) in pleural effusion of lung diseases.

Pleural effusions of seven lung cancer patients (mean age; 58) and seven non-cancer patients (mean age; 49) were examined and Cu(2+) was measured in ceruloplasmin and Fe(3+) in transferrin signals by electron spin resonance (ESR) method. The variations of total Fe and Cu ions, ceruloplasmin and transferrin, proteins, neutrophil cell counts, LDH and nitrite/nitrate were also examined. The Cu(2+) peak was decreased and the Fe(3+) peak was increased in the cancer group. The interrelationship among Cu(2+), total Cu and ceruloplasmin, and among Fe(3+), total Fe and transferrin clarified that Cu(2+) and Fe(3+) are not a representative of ceruloplasmin and transferrin, respectively. The ratio of Cu(2+)/Fe(3+) in pleural effusion distinguished lung cancer from benign inflammation as a cause. The ratio of total Cu/total Fe measured by the chemical analysis method also distinguished these, but the ratio of ceruloplasmin/transferrin was unable to distinguish the cancer. In conclusion, the simple and rapid measurement of Cu(2+)/Fe(3+) by ESR effectively abstracts the variation of total ion concentrations caused by malignant disease.

A method to estimate the ratio of absorption coefficients of two wavelengths using phase modulated near infrared light spectroscopy.

Near infrared spectroscopy provides a very useful tool to monitor the oxygen saturation of the living tissue non-invasively. We can calculate the hemoglobin oxygen saturation within the tissue, using the ratio of the absorption coefficient (mu a) at two different wave lengths of light. Biological tissue has a very high effective scattering factor (mu s), which elongates an optical path length and makes it difficult to compute the mu a by the conventional method using continuous light. Phase Modulated Spectroscopy (PMS) measures the path length which is a complex function of the mu a and mu s. To get the ratio of the mu a, we have to eliminate the effects of the mu s from the obtained value by the PMS method. In this report, we present a theory and an experimental result which show that the inverse of the squared ratio of two phase angle differences at two different separations obtained by two different light wavelengths provides a good estimate of the ratio at these wavelength.

Optical imaging of human breast cancer.

Since an increasing number of breast cancers have been reported in recent years, there is a need for improving techniques for early detection of the breast cancer. Here we tested a time gated optical imaging technique as a tool for imaging human breast. Pulsed laser light at wavelengths of 780 and 830 nm are transmitted through human breast tissues and time spectra of the diffused light through the tissue are recorded over nanoseconds. Data from different locations are acquired and used to reconstruct a two dimensional image as a set of spectra in pixel form. The imaging consists of absorption and scattering coefficients, and the absorption coefficients at the two wavelengths are related to oxygen concentration and blood volume. The analysis of these coefficients is based upon the early arrival photons, therefore allowing construction of a better image than those from the current diaphanography. We demonstrate images of breast cancer, cysts created after lumpectomy, and consequences of radiation therapy. Results show that time gated optical imaging can image oxygen concentration in the cancerous and fibrotic breasts. Resolution of the imaging for smaller tumor size needs to be improved.

Energy metabolism and cerebral blood flow during cytotoxic brain edema induced by 6-aminonicotinamide.

We investigated the progression of cytotoxic brain edema induced by 6-aminonicotinamide (6-ANA), a potent antimetabolite of nicotinamide, by measuring the time courses of changes in brain tissue water state (with MRI), histology (with H&E staining), energy metabolism (with 31P-NMR), brain hemoglobin concentration (with near-infrared spectroscopy; NIRS), cerebral blood flow and volume (CBF. CBV), mean arterial blood pressure (MABP), and brain activity (with EEG) up to 10 hours (h). Change in cerebrovascular autoregulation was also investigated. 6-ANA (120 mg/kg) was administered intraperitoneally to 30 male Wistar rats (250-350 g). After 10 h, the T2-weighted signal intensity was increased (p < 0.05), and H&E staining showed severe vacuolation of glial cells. ATP production/consumption and intracellular pH were well maintained up to 10 h, while the intensity of the phosphomonoesters (PME) signal was significantly increased (p < 0.05). Oxygen consumption gradually decreased from 4 to 10 h. CBF and MABP were all significantly increased (by 2.5-fold for CBF) (p < 0.05). Theta and delta wave amplitudes were reduced at 10 h. In summary, 6-ANA (120 mg/kg) induced cytotoxic brain edema from 4 to 10 h. Energy balance and brain activity were well maintained up to 10 h, though cerebrovascular autoregulation was impaired.

Distribution of brain oedema in the contralateral hemisphere after cerebral infarction: repeated MRI measurement in the rat.

The appearance of local cerebral dysfunction at remote regions from the focus in the acute stage of stroke (diaschisis) is well known, but its mechanism has not been established. We have analysed serial MR images of the infarcted brain of rats to evaluate the distribution of oedema. Forty-seven Sprague-Dawley rats were anaesthetized with halothane, and the right middle cerebral artery (MCA) was permanently occluded via the intraluminal approach using a nylon 2-0 suture. At 3, 6, 9 and 24 hours after the occlusion, coronal T(2)-weighted MR images were taken and the signal intensity (SI) was computed at each region of the brain. After occlusion of the right MCA, SI increased diachronically up to 24 hours on the occluded side of the cortex (52.9+/-3.2 to 104.8+/-22.4) and striatum, which are within the perfusion territory of the MCA. SI increment was also observed at the hippocampus, alveus hippocampi and pyriform lobe, which are not within the territory of the MCA, and at some regions of the contralateral side (52.5+/-4.8 to 69.4+/-14.8 at the cortex). These changes were prominent in ischaemia-vulnerable portions, mild in the cortex, and minimal in the striatum. This contralateral side SI increment indicates remote oedema, which corresponds to diaschisis. We suggest that the mechanism of this remote contralateral oedema is the movement of extravasated protein from the lesion.

[Long-term gadolinium-enhancement of cauda equina on MRI in a case of spinal cord infarction after epidural anesthesia].

A 49-year-old woman developed paraplegia 26 hours after appendectomy under epidural and general anesthesia. Systolic blood pressure fell to 85 mmHg for 25 minutes after epidural anesthesia, which was performed at the level of the L1/2 intravertebral space. Neurological examination revealed paraplegia and superficial sensory impairment below the level of the L 1 spinal cord. The bladder was atonic by cystometry. MRI showed gadolinium enhancement of the cauda equina extending over a long period (3 months) and spinal cord infarction. The infarction was at the level of 10th thoracic spinal vertebra to conus and was limited to the gray matter of the spinal cord. We consider that the reason for spinal cord infarction was prolonged hypotension of the patient, who was diabetic, hypertensive and hypercoagulopathic. The blood supply to the gray matter is mainly from the central artery which is derived from the anterior spinal artery, and the gray matter is particularly vulnerable to hypotension. Our hypotheses concerning gadolinium enhancement of the cauda equina are the following: 1) enhancement of the cauda equina was seen due to collateral formation after spinal cord infarction, and 2) long-term enhancement of the cauda equina was observed due to an ischemic lesion involving a large area.

Analysis of factors causing signal loss in the measurement of lung tissue water by nuclear magnetic resonance.

The water content of lung, brain, and muscle tissue was measured by nuclear magnetic resonance (NMR) and compared with gravimetric determinations. The NMR signal intensity of water was measured by a single 90 degree pulse and by a spin-echo sequence. The absolute water content was determined by the difference in the sample's weight before and after desiccation. The NMR detectable water in each tissue was expressed as a percentage of the signal intensity for an equal weight of distilled water. Using the single pulse measurement, 67% of the gravimetrically-measured water was detected in collapsed lung samples (consisting of about 47% retained air), in contrast to 96% for brain and 98% for muscle. For degassed lung samples, the NMR detectability of water increased to 87% with the single pulse measurement and to 90% with the spin-echo measurement, but the values remained significantly less than those of brain or muscle. Factors that caused the NMR signal loss of 33% in collapsed lung samples were: air-tissue interfaces (20%), microscopic field inhomogeneity (3%), and a water component with an extremely short magnetization decay time constant (10%).

Quantification of water content in biological tissues by proton nuclear magnetic resonance.

We have made quantitative measurements of water content in biological tissue using proton nuclear magnetic resonance (NMR). We evaluated the factors which affect the NMR signal intensity measurements in order to quantify the absolute water content of the tissue. It can be said that there is an optimum sample length to achieve the absolute value of water content using NMR. The integrated NMR water signal intensity was determined in the frequency domain. The absolute water content was measured gravimetrically. The NMR detectable water in brain and lung tissue was determined using the signal intensity of the analyzed tissue compared with the signal intensity for the same weight of distilled water. The NMR detectable water was 99% by weight for brain and 60% by weight for peripheral lung tissue. The NMR detectability of water in biological tissues varied for different tissues.

Interpretation of pathophysiology by laboratory data (3). A consultation program based on clinical laboratory data.

Based on previous studies, a consultation program using clinical laboratory data has been constructed. After converting all data into the standard deviation index (SDI), the score for preregistered diseases was calculated by integrating products of SDI and the weighting factors (WF) pre-determined empirically by medical experts for each item. Ten diseases in order of their maximum scores, the most predictable ones, and additional comments were printed out. The principle of our consultation program is based on the modified Bayesian theory which employs, instead of probability a posteriori, weighting factors (WF) corresponding to the grade of membership in the "fuzzy set" concept. Evaluations based on this interpretation performed 2-3 times during the clinical course in nine patients were found to agree qualitatively with each clinical course and diagnosis. This report also contains 1) an outline of the progress of this consultation program in Japan and abroad, 2) the actual level of acceptance of this system by physicians, 3) and the characteristics and problems of our program. We are now planning to report a quantitative evaluation of this program using many cases in some specified field, instead of one case of each disease.

Dependence of transverse relaxation time T2 of biologic tissues on the interpulse delay time in Carr-Purcell-Meiboom-Gill (CPMG) measurements.

To determine the transverse relaxation time (T2) of biological tissues in nuclear magnetic resonance measurements, the Carr-Purcell-Meiboom-Gill (CPMG) method has been recommended to avoid the effect of external magnetic field inhomogeneity on T2 values. However, a dependence of T2 on the interpulse delay time (IPDT) in the CPMG measurements has been shown for biological tissues. The present study examined the dependence of the T2 on IPDT for muscle, lung (passively collapsed or degassed), and brain tissues. It was found that the CPMG T2 of the lung was strongly dependent upon the IPDT, in contrast to muscle and brain tissues. The IPDT dependence of the CPMG T2 for lung tissue, which was lessened by degassing, was affected by the magnetic field inhomogeneity due to air-tissue interfaces, but not by the spin-locking effect, since the T2 measured by the Carr-Purcell-Freeman-Hill (CPFH) method did not show this dependence. These results should aid in the evaluation of T2 values for biological tissues measured under various conditions and by different techniques.

Differentiation of lung cancer and radiation fibrosis using magnetic resonance images: a case study.

We used magnetic resonance imaging to differentiate residual and recurrent lung cancer from the surrounding radiation pulmonary fibrosis in a 62-year-old patient. The cancer's signal intensity was greater than the fibrotic lung tissue's intensity in an ECG-gated image with relatively short repetition and echo times and, also, in images with long repetition and echo times.

[Clinical effect of alprazolam and trazodone on bronchial asthmatics with anxiety disorder].

Onset as well as many symptoms of asthma are said to be related to autonomic dysfunction which often appear as a result of actual daily stress of the patients. Minor tranquilizers and anti-depressants are often successful in treating such symptoms, though precise effect of these drugs on asthma is not yet available, while many still hesitate to use these drug for fear of the anticholinergic effect which may hinder the efficient expectoration of sputum which could be critical during severe asthma attacks. In this study, these drugs were evaluated by the asthma score, peak flow, acetylcholine provocation test and the suppressive effect on lymphocytes. They could be beneficial in increasing the quality of asthma therapy if employed with necessary care.