Theoretical investigation of (−)1-(Benzofuran-2-yl)-2-propylaminopentane [(−)-BPAP] as a hydroxyl radical scavenger

The chemical reactions between (-)-BPAP and .OH were studied using molecular orbital theory, with several simplified models. (-)-BPAP was proved to be a good radical scavenger. It was found that every atom of the benzofuran ring, except carbon 3, was capable of easily trapping the radical, where the most active site was carbon 1 on the furan part. The activation energies for the trappings were ca. 10kcal/mol by the calculations at UHF/6-31G(d)//UHF/3-21G level. Since the single radical trapping products were still radicals, these could trap further radicals by way of cascade without any activation energy. Thus, the double radical trapping products were very stable, of which the lowest energy level was about 80kcal/mol lower than the starting reactants.

Health-related quality of life among dialysis patients in Seattle and Aichi

We used the 36-item Short-Form Health Survey to compare health-related quality of life (HRQOL) between 104 dialysis patients in Seattle, WA, and 2,178 patients in Aichi, JAPAN: Compared with Aichi patients, Seattle patients had lower scores on three scales related to physical HRQOL: Physical Functioning (PF; P = 0.03), Role-Physical (RP; P = 0.004), and Vitality (VT; P < 0.001). However, scores related to mental HRQOL were higher for Seattle patients compared with those of Aichi patients, which included scores for Role-Emotional (RE; P = 0.005) and Mental Health (MH; P < 0.001). Scores for Bodily Pain, General Health Perception, and Social Functioning did not differ significantly between the two groups. These differences persisted even after potential confounding factors were controlled for. However, after taking into account national norm data for the United States and Japan, differences in PF and VT disappeared, whereas differences in RP, RE, and MH persisted. These results suggest that the higher scores for PF and VT in Aichi patients were partly explained by the higher physical HRQOL of the Japanese general population. Although these data may not be representative of the total dialysis populations in the United States and Japan, they suggest potential differences in HRQOL between patients in the two countries. Additional research is needed to confirm these results and understand the factors associated with these differences. The findings suggest the need for further attention to the physical limitations of US dialysis patients and the mental health of Japanese dialysis patients.

Artificial neural network-based predictive model for bacterial growth in a simulated medium of modified-atmosphere-packed cooked meat products

The data of Devilieghere et al. (Int. J. Food Microbiol. 1999, 46, 57--70) on bacterial growth in a simulated medium of modified-atmosphere-packed cooked meat products was processed for estimating maximum specific growth rate mu(max) and lag phase lambda of Lactobacillus sake using artificial neural networks-based model (ANNM) computation. The comparison between ANNM and response surface methodology (RSM) model showed that the accuracy of ANNM prediction was higher than that of RSM. Two-dimensional and three-dimensional plots of the response surfaces revealed that the relationships of water activity a(w), temperature T, and dissolved CO(2) concentration with mu(max) and lambda were complicated, not just linear or second-order relations. Furthermore, it was possible to compute the sensitivity of the model outputs against each input parameter by using ANNM. The results showed that mu(max) was most sensitive to a(w), T, and dissolved CO(2) in this order; whereas lambda was sensitive to T the most, followed by a(w), and dissolved CO(2) concentrations.

Increased heat-escape/cold-seeking behavior following hypertonic saline injection in rats

We examined the effect of hypertonic saline injection on heat-escape/cold-seeking behavior in desalivated rats. Rats were exposed to 40 degrees C heat after normal (154 mM NaCl, control) or hypertonic saline (2,500 mM NaCl) injection (1 ml/100 g body wt). The rats received a 0 degrees C air for 30 s when they entered a specific area in an experimental box. Core temperature (T(c)) surpassed 40 degrees C in both conditions when 0 degrees C air was not available. Hypertonic saline injection produced a lower baseline T(c) than control [36.9 +/- 0.2 and 37.9 +/- 0.2 degrees C (means +/- SE), P < 0.05] and a greater number of 0 degrees C air rewards during the 2-h heat with lower T(c) at the end (48 +/- 1 and 34 +/- 2, 37.6 +/- 0.1, and 37.3 +/- 0.1 degrees C in the control and hypertonic saline injection trial, respectively, P < 0.05, n = 6). However, T(c) was similar (37.7 +/- 0.2 and 37.6 +/- 0.4 degrees C in the control and hypertonic saline injection trial, n = 5) when 0 degrees C air was automatically and intermittently (35 times) given during the heat. Rats augment heat-defense mechanisms in response to osmotic stress by lowering the baseline T(c) and increasing heat-escape/cold-seeking behavior.

Comparison between resonant Lalpha emission spectra and resonant LMM Auger spectra of yttrium compounds

Resonant Lalpha x-ray emission spectra (RXES) and resonant LMM Auger emission spectra (RAES) of Yttrium compounds were measured across YL(III) absorption threshold. When the incident photon energy is bellow the absorption threshold, only Raman scattering component is commonly observed in both spectra. Above the absorption threshold, Raman and normal Lalpha (or normal LMM Auger) emission peaks are observed in insulator samples. These spectral features are almost same in both RXES and RAES processes, except for the relative intensity ratio between these Raman peaks and normal Lalpha (or normal LMM Auger) emission peaks. Comparing these two spectra, useful information about the deexcitation of core hole can be obtained.

Role of autologous blood transfusion in sacral tumor resection: patient selection and recovery after surgery and blood donation

We carried out sacral en-bloc resection in six patients (three with chordoma; one with pheochromocytoma; one with malignant schwannoma; and one with giant cell tumor) using preoperatively collected autologous blood, to avoid homologous blood transfusion. An average of 3200 ml was collected preoperatively, with patients receiving recombinant human erythropoietin (r-HuEPO), at a total dose of 130 000 units on average. In four patients, we were able to accomplish the surgery without homologous blood transfusion. Postoperatively, the hemoglobin level in these four patients recovered to the pre-collective level in 4.5 weeks, on average. These clinical results indicate that en-bloc sacrectomy, which requires a large volume of blood transfusion, can be accomplished with preoperatively collected autologous blood alone.

Neuronal circuitries involved in thermoregulation

The body temperature of homeothermic animals is regulated by systems that utilize multiple behavioral and autonomic effector responses. In the last few years, new approaches have brought us new information and new ideas about neuronal interconnections in the thermoregulatory network. Studies utilizing chemical stimulation of the preoptic area revealed both heat loss and production responses are controlled by warm-sensitive neurons. These neurons send excitatory efferent signals for the heat loss and inhibitory efferent signals for the heat production. The warm-sensitive neurons are separated and work independently to control these two opposing responses. Recent electrophysiological analysis have identified some neurons sending axons directly to the spinal cord for thermoregulatory effector control. Included are midbrain reticulospinal neurons for shivering and premotor neurons in the medulla oblongata for skin vasomotor control. As for the afferent side of the thermoregulatory network, the vagus nerve is recently paid much attention, which would convey signals for peripheral infection to the brain and be responsible for the induction of fever. The vagus nerve may also participate in thermoregulation in afebrile conditions, because some substances such as cholecyctokinin and leptin activate the vagus nerve. Although the functional role for this response is still obscure, the vagus may transfer nutritional and/or metabolic signals to the brain, affecting metabolism and body temperature.

Dose measurement, its distribution and individual external dose assessments of inhabitants in the high background radiation areas in China

As a part of the China-Japan cooperative research on natural radiation epidemiology, we have carried out a dose-assessment study to evaluate the external exposure to natural radiation in the high background radiation areas (HBRA) of Yangjiang in Guangdong province and in the control areas (CA) of Enping prefecture since 1991. Because of the difficulties in measuring the individual doses of all inhabitants directly by personal dosimeters, an indirect method was applied in which the exposed individual doses were estimated from the environmental radiation doses measured by survey meters and the occupancy factors of each hamlet. We analyzed the dose in the hamlets and the variation in the occupancy factors to obtain the parameters of dose estimation on the inhabitants in selected hamlets; Madi and several hamlets of different dose levels in HBRA and Hampizai hamlet in CA. With these parameters, we estimated individual dose rates and compared them with those obtained from direct measurement using dosimeters carried by selected individuals. The results obtained are as follows. 1) The environmental radiation doses are influenced by the natural radioactive nuclide concentrations in building materials, the age of the building and the arrangement of the houses in a hamlet. There existed a fairly large and heterogeneous distribution of indoor and outdoor environmental radiations. The indoor radiation doses were due to exposure from the natural radioactive nuclides in the building materials and were about two times as large as the outdoor radiation doses. The difference between indoor and outdoor doses was not observed in CA. 2) The occupancy factor was influenced by the age of individuals and by the season of the year. The occupancy factor was higher for infants and aged individuals than for other age groups. This lead to higher dose rates of exposure to those age groups. 3) A good correlation was observed between the dose assessed indirectly and that measured directly and the correlation factor was 0.97.

Dose-effect relationship of dicentric and ring chromosomes in lymphocytes of individuals living in the high background radiation areas in China

Chromosomes of 39 healthy family members (3 generations from 13 families) living both in the high-level background radiation areas (HBRA) and the control areas (CA) were studied. Cumulative dose from birth to the time of blood sampling was estimated by calculating measured exposure rate in each individual. The cumulative doses ranged 30.9-358.9 and 6.0-59.2 mGy for HBRA and CA, respectively. Peripheral lymphocyte chromosome preparations were made according to our improved method. Dicentric and ring chromosomes (Dic + Rc) were scored in average 2,527 cells per individual in HBRA and 2,694 cells in CA under a microscope equipped with an automated stage. A positive correlation between Dic + Rc and age was found in HBRA, while no such dose relationship was clear in CA. The frequency of Dic + Rc linearly increases over lifetime due to chronic low dose exposure and it is likely that the activation of repair enzymes is not triggered in the present HBRA. Threshold dose (rate) of the induction of chromosome aberrations, if any, is below the present dose (rate) level.

Anorectal and bladder function after sacrifice of the sacral nerves

STUDY DESIGN

The quantitative changes in anorectal and bladder functions after sacrifice of the sacral nerves were assessed.

OBJECTIVES

To evaluate the bladder and anorectal functions before and after sacral nerve division in patients with sacral bone tumors.

SUMMARY OF BACKGROUND DATA

The quantitative changes in bladder and anorectal functions after sacrifice of the sacral nerves have not been intensively studied. The purpose of this investigation was to measure the bladder and anorectal function before and after sacral nerve division using manometry and cystometry.

METHODS

Surgical resection of a sacral tumor was performed in five patients. The sacral nerves were sacrificed bilaterally in three patients and unilaterally in two patients. Anorectal function was evaluated on the basis of symptoms and physiologic tests. Micturition function was evaluated based on symptoms, and intravesical pressures were measured by cystometry.

RESULTS

The two patients with unilateral sacral nerve loss did not experience subjective problems with defecation or micturition, although the residual volume of urine was increased after surgery. Two of the three patients with bilateral sacral nerve loss had no urge to defecate, were unable to differentiate between feces and flatus, and experienced no urgency. Fecal incontinence was uncommon because of firm feces. It was possible to control defecation using enemas on alternate days. The third patient underwent colostomy because the maximum resting pressure, which is controlled by the hypogastric nerves, was affected before surgery.

CONCLUSION

Unilateral sacrifice of sacral nerves results in little bladder or anorectal dysfunction.

[Value of upper gastrointestinal endoscopic examination of head and neck cancer patients]

Between January 1995 and March 1999, we performed the upper gastrointestinal endoscopic examinations on 287 patients with head and neck cancers and detected 23 cases (8%) of esophageal cancer and 8 cases (2.8%) of gastric cancer, showing how frequently esophageal cancer occurs in head and neck cancer. The esophageal cancer involved the oral cavity in 8 cases (9.5%), the oropharynx in 3 cases (8.6%), the hypopharynx in 10 cases (19.6%), and the larynx in 2 cases (2%). Esophageal cancer occurred most frequently in hypopharyngeal cancer, particularly the pyriform sinus type and the postcricoid type. We conclude that upper gastrointestinal endoscopic examination, including Lugol staining, is necessary in head and neck cancer patients.

Gender difference in the mean age at the induction of hemodialysis in patients with autosomal dominant polycystic kidney disease

Male patients with autosomal dominant polycystic kidney disease (ADPKD) begin hemodialysis earlier than female patients. The rate of progression of many other renal diseases is also faster in men than women. In this study, gender difference in ADPKD was compared with that in other diseases, such as chronic glomerulonephritis, diabetic nephropathy, and nephrosclerosis, using the data obtained from an annual statistical survey of the Japanese Society for Dialysis Therapy. The male-female ratio in ADPKD (n = 8,176) was 1.17:1 and closer to 1.0:1 than the other diseases. Men with ADPKD started hemodialysis therapy 1.3 years earlier than women (male age, 55.9 +/- 12.4 years versus female age, 57.2 +/- 11.5 years), and the age difference was less than that in other diseases. These results suggest that the prognosis in women with ADPKD is relatively worse than that in men with ADPKD or that women are not well protected against the progression of this disease compared with other renal diseases. In conclusion, men with ADPKD are introduced to hemodialysis therapy earlier than women; however, the age difference was small compared with other common renal diseases.

Solid phase microextraction/gas chromatography of Salmonella-infected beef

Eight strains of Salmonellae were incubated in TSB culture medium at 37 degrees C for 24 h. Volatile compounds derived from the bacteria were collected using solid-phase microextraction fibers and then applied to gas chromatography (GC). Similarity analysis of the GC patterns thus obtained could separate these strains on principal component similarity (PCS) scattergrams. Five major food-related pathogenic bacteria and 10 other bacteria (including one Salmonella strain) were also classified by growing in the same medium. It is then proposed to utilize this approach to improve the GC/PCS method of Nakai et al. [Nakai, S.; Wang, Z. H.; Dou, J.; Nakamura, S.; Ogawa, M.; Nakai, E.; Vangerstoep, J. J. Agric. Food Chem. 1999, 47, 576-583] that has been developed for screening safe foods by detecting bacteria contaminated foods. Inoculating food samples pre-enriched through preliminary incubation into a culture medium and then subjecting to the GC/PCS method after secondary incubation enhances the detectability of pathogenic bacteria.

Mmh/Ogg1 gene inactivation results in accumulation of 8-hydroxyguanine in mice

The major mutagenic base lesion in DNA caused by exposure to reactive oxygen species is 8-hydroxyguanine or 7, 8-dihydro-8-oxoguanine (8-OH-G). Products of the human MMH/OGG1 gene are known to catalyze in vitro the reactions repairing this DNA lesion. To analyze the function of Mmh in vivo, we generated a mouse line carrying a mutant Mmh allele by targeted gene disruption. Mmh homozygous mutant mice were found to have a physically normal appearance, but to have lost nicking activity in liver extracts for substrate DNA containing 8-OH-G, exhibiting a 3-fold increased accumulation of this adduct at 9 weeks of age compared with wild-type or heterozygous mice. Further elevation to 7-fold was observed in 14-week-old animals. Substantial increase of spontaneous mutation frequencies was clearly identified in Mmh mutant mice bearing transgenic gpt genes. These results indicate that exposure of DNA to endogenous oxidative species continuously produces the mutagenic adduct 8-OH-G in mice, and Mmh plays an essential role in repair of this DNA damage.

Physicochemical changes and mechanism of heat-induced gelation of arrowtooth flounder myosin

Physicochemical changes of myosin during heating were investigated to elucidate the mechanism of heat-induced gelation of arrowtooth flounder (ATF) myosin at high ionic strength. Changes in dynamic properties indicated ATF myosin formed a gel in three different stages as shown by the first increase in G' (storage modulus) at 28 degrees C, followed by the decrease at 35 degrees C and the second increase at 42 degrees C. DSC thermogram showed the onset of myosin denaturation at 25 degrees C with two maximum transition temperatures at 30 and 36 degrees C. The decrease in alpha-helical content indicated ATF myosin began to unfold at 15 degrees C and the unfolding continued until it reached 65 degrees C. Turbidity measurement showed myosin began to aggregate at 23 degrees C and the aggregation was complete at 40 degrees C. Surface hydrophobicity increased consistently in the temperature range studied, 20-65 degrees C. Sulfhydryl contents decreased significantly at 20-30 degrees C due to the formation of disulfide linkages but remained constant at temperatures >30 degrees C. ATF myosin was shown to be extremely sensitive to heat, resulting in denaturation at lower temperature than other fish myosin. Denaturation was initiated by unfolding of the alpha-helical region in myosin followed by exposure of hydrophobic and sulfhydryl residues, which are subsequently involved in aggregation and gelation processes.

Experimental study on the dynamics of lumbosacral nerve root circulation

STUDY DESIGN

Experimental investigation of the dynamics of nerve root circulation.

OBJECTIVES

To study the dynamics of lumbosacral nerve root circulation by using seriography in dogs.

SUMMARY OF BACKGROUND DATA

The vascular distribution to the nerve root has been discussed mainly from the morphologic aspects, and no adequate elucidation has been presented concerning the kinetics of the blood supply to the nerve root.

METHODS

To investigate the direction of blood flow in the nerve roots, a series of photographs of the cauda equina were taken using a motor-driven camera immediately after 3 mL of india ink was injected through the aortic catheter manually. The changes in the blood flow direction caused by compression of the nerve root also were observed. After the dog was killed, the nerve roots were cleared by the Spalteholz technique to identify the vessels observed during the experiment.

RESULTS

The blood flow in the radicular arteries was descending in the proximal part and ascending in the distal part of the nerve roots. This observation supports the suggestion that there is a so-called watershed of the blood flow in the radicular arteries themselves. However, when the ascending radicular artery of the nerve root was cramped, the radicular blood flow on the proximal side was downward. The microangiograms also showed that there were abundant anastomoses of intrinsic vessels in the nerve roots.

CONCLUSIONS

There is no relatively hypovascular region in the nerve root that is vulnerable in the course of degenerative changes in the lumbosacral spine. Therefore, it is unlikely that the watershed represents a weak point of the blood flow in the nerve root.

Anterior transvertebral herniotomy for cervical disk herniation

This study analyzed the results of anterior transvertebral herniotomy for cervical disk herniation to assess the utility of this procedure. Anterior transvertebral herniotomy was performed in 24 patients who had cervical disk herniation without spinal canal stenosis. In most patients, a good result was obtained, but simultaneous or subsequent anterior intervertebral fusion was necessary in four patients. In one (4%) patient, the two adjacent vertebrae had fused spontaneously. The best indication for this treatment judging from the postoperative results is a large disk hernia associated with either myelopathy or radiculopathy, but without spinal canal stenosis.

Calbindin-D28k and calretinin in the rat posterior pituitary; light and electron microscopic localization and upregulation with dehydration

Ca(2+) binding proteins (CaBPs), calbindin-D(28k) (calbindin) and calretinin, are thought to contribute to the regulation of intracellular Ca(2+) in many neuronal populations and perhaps more importantly, signal functional modulation in neuronal activity. In the present experiments, light microscopic immunohistochemistry revealed that the immunoreactivity of calbindin and calretinin was contained in varicose axons in the posterior pituitary. The dual labeling study with confocal microscopy demonstrated that calbindin immunoreactivity was present in the terminals of both oxytocin (OXT) and arginine-vasopressin (AVP) neurons. However, calretinin immunoreactivity was exclusively seen in the OXT terminals. Moreover, the dual labeling study showed that most calretinin-positive terminals contained calbindin immunoreactivity, demonstrating the colocalization of calbindin and calretinin in the same OXT nerve terminals. By electron microscopy, calbindin and calretinin immunoreactivities were seen in the neurosecretory axons and nerve terminals. These immunoreactive nerve terminals were seen to contain more clear microvesicles than dense-core neurosecretory granules. This immunoelectron microscopic observation suggests that both calbindin and calretinin localize preferentially in the active zone of the nerve terminals, which usually face the perivascular space around fenestrated capillaries. In spite of similar localization of calbindin and calretinin within the posterior pituitary, Western blot analysis showed some differences between the two CaBPs. Calbindin was present mostly in the soluble fraction with little in the insoluble fraction, but a substantial portion of calretinin was present in both the insoluble and soluble fractions. Moreover, dehydration induced by drinking 2% NaCl solution and deprivation of drinking water increased calretinin levels in the posterior pituitary as compared with control, but the calbindin level was not changed. The present findings demonstrate that calbindin and calretinin colocalize in the active zones of OXT nerve terminals, but only calretinin is upregulated with dehydration, suggesting different physiological role of calbindin and calretinin in the nerve terminals.

Deaths from heat-stroke in Japan: 1968-1994

Global warming is increasingly recognized as a threat to the survival of human beings, because it could cause a serious increase in the occurrence of diseases due to environmental heat during intermittent hot weather. To assess the direct impact of extremely hot weather on human health, we investigated heat-related deaths in Japan from 1968 through 1994, analyzing the data to determine the distribution of the deaths by age and their correlation to the incidence of hot days in summer. Vital Statistics of Japan, published by the Ministry of Health and Welfare of Japan, was the source of the heat-related mortality data employed in this study. Meteorological data were obtained from the District Meteorological Observatories in Tokyo and Osaka, the two largest cities in Japan. Heat-related deaths were most prone to occur on days with a peak daily temperature above 38 degrees C, and the incidence of these deaths showed an exponential dependence on the number of hot days. Thus, even a small rise in atmospheric temperature may lead to a considerable increase in heat-related mortality, indicating the importance of combating global warming. Furthermore, half (50.1%) of the above-noted deaths occurred in children (4 years and under) and the elderly (70 years and over) irrespective of gender, indicating the vulnerability of these specific age groups to heat. Since a warmer climate is predicted in the future, the incidence of heat waves will increase, and more comprehensive measures, both medical and social, should be adopted for children of 4 years and younger the elderly to prevent heat-related deaths in these age groups.