Short-term oral toxicity of pentyl ether, 1,4-diethoxybutane, and 1,6-dimethoxyhexane in male rats.

Pentyl ether (PE) and two newly synthesized polyoxy ethers, 1,4-diethoxybutane (DEB) and 1,6-dimethoxyhexane (DMH), have been proposed as candidate diesel fuel additives. To characterize and compare their toxicity and to provide information for risk assessment, a 4-week oral study was conducted on these compounds. Male Sprague-Dawley rats (288 +/- 20 g) were divided into groups of seven animals each, and were administered by gavage low (2 mg/kg body weight), medium (20 mg/kg body weight), or high (200 mg/kg body weight) doses of PE, DEB, or DMH, respectively, 5 days/week for 4 weeks. Animals in the control group received the vehicle (corn oil, 1 ml/100 g body weight) only. At the end of the exposure period, relative testis and thymus weights were reduced by 30 and 46%, respectively, in animals treated with the high dose of DMH. Significant reductions in serum lactate dehydrogenase (LDH), serum uric acid, and blood platelet counts were also observed in the high dose of DMH. Serum corticosterone was significantly depressed in the high doses of PE and DEB and in the low dose of DMH. Serum thiobarbituric acid-reactive substances (TBARS) were decreased (p < 0.05) in all DMH treatment groups and in the medium and high dose PE and DEB groups, while liver TBARS were unaffected by treatment. In the liver, increased glutathione (GSH) level and glutathione-S-transferases activity were detected in the high dose DMH group. Urinary ascorbic acid levels were markedly increased in animals receiving the high doses of PE, DEB, and DMH. Urinary formic acid was increased by 13 times in the high dose PE and DEB groups. Testes of all animals receiving the high dose of DMH showed a moderate to marked degree of degeneration of the seminiferous tubules, including a mild degree of vacuolation. At the same time, the epididymis of these animals had substantially reduced sperm density with prominent presence of spermatid giant cells. Mild histological changes were seen in the liver at all dose levels for all three chemicals. Thyroid effects were also observed in the high dose PE and DEB groups and in the medium and high dose DMH groups. It was concluded that DMH is the most toxic of the three ethers tested, with testicular, epidiymal, and thymic effects being the most prominent at 200 mg/kg. Other significant changes included depressed platelet counts and serum biochemical changes. Increased production of formic acid, an ocular toxin, from PE and DEB treatments may also be of toxicological concern.     

Obscure bleeding in the gastrointestinal tract originating in the small intestine.

In the past 12 years, we operated upon 49 patients with bleeding lesions of the small intestine. After endoscopic examination and barium studies of the upper and lower gastrointestinal tract excluded esophagogastroduodenal and lesions of the colon and rectum, preoperative examinations consisted of technetium-99m pertechnetate scan, technetium-99m labeled erythrocyte scan, barium studies of the small intestine and selective visceral angiogram. In one patient, diagnostic laparotomy had to be done before any procedure because of severe bleeding and angiosarcoma of the ileum. The results of gross examination at operation revealed bleeding lesions in 40 patients. Special intraoperative localization procedures consisting of methylene blue injection through superselectively prepositioned angiographic catheter was done on eight patients, and intraoperative enteroscopy was done on 17 patients. These two procedures were complementary, having their own indications and limitations. Our regimen of preoperative and intraoperative localization procedures was effective in the management of bleeding small intestinal lesions.     

麝香的药理研究 Ⅱ.麝香及其有效成分的抗炎作用

麝香水提物对小鼠巴豆油耳部炎症,大鼠琼脂性关节肿、酵母性关节肿、佐剂型多发性关节炎均具非常显著的抑制作用。对大鼠烫伤性血管渗透性增加、羧甲基纤维素引起的腹腔白细胞游走亦具非常明显的抑制作用。静脉注射麝香1号对巴豆油小鼠耳炎症的50%抑制剂量为0.63 mg/kg,为氢化可的松作用强度的36倍,如以克分子剂量相比,则为氢化可的松的500倍以上。静脉注射麝香水提物对小鼠的LD_(50)及95%可信限为848±104 mg/kg。     

Enteric-coated peppermint-oil capsules in the treatment of irritable bowel syndrome: A prospective, randomized trial

To determine the efficacy and tolerability of an enteric-coated peppermint-oil formulation (Colpermin), we conducted a prospective, randomized, double-blind, placebo-controlled clinical study in 110 outpatients (66 men/44 women; 18–70 years of age) with symptoms of irritable bowel syndrome. Patients took one capsule (Colpermin or placebo) three to four times daily, 15–30 min before meals, for 1 month. Fifty-two patients on Colpermin and 49 on placebo completed the study. Forty-one patients on Colpermin (79%) experienced an alleviation of the severity of abdominal pain (29 were pain-free); 43 (83%) had less abdominal distension, 43 (83%) had reduced stool frequency, 38 (73%) had fewer borborygmi, and 41 (79%) less flatulence. Corresponding figures for the placebo group were: 21 patients (43%) with reduced pain (4 were pain-free) 14 (29%) with reduced distension, 16 (32%) with reduced stool frequency, 15 (31%) with fewer borborygmi, and 11 (22%) with less flatulence. Symptom improvements after Colpermin were significantly better than after placebo (P<0.05; Mann-Whitney U-test). One patient on Colpermin experienced heartburn (because of chewing the capsules) and one developed a mild transient skin rash. There were no significant changes in liver function test results. Thus, in this trial, Colpermin was effective and well tolerated.     

Macular pigment optical density in young Chinese adults

PURPOSE: The purpose of this study was to determine the macular pigment optical density (MPOD) in a group of Chinese subjects using a simple customized light emitting diode-based device. METHODS: Heterochromatic flicker photometry was used in this study. With a 1 degrees diameter circular test stimulus, MPOD was estimated by comparing the relative sensitivities to a blue light, against a green reference, between foveal and parafoveal 4 degrees temporal locations. Fixed alternating frequencies were used. Repeatability was determined on a small group of subjects. A further group of 67 young healthy subjects provided data for MPOD norms. RESULTS: All results were corrected to the common MPOD reference wavelength of 460 nm. The group-averaged MPOD was 0.48 (S.D. 0.23). We found no gender difference in MPOD. The coefficient of variability was 7.2-8.0% and the coefficient of repeatability was 0.12. CONCLUSIONS: The MPOD of Chinese subjects did not differ greatly from the reported MPOD in white subjects.     

Consulting dietitians in nursing homes: time in role functions and perceived problems

A mail survey was conducted to describe Illinois consultant dietitians' perceptions of time adequacy for fulfilling role responsibilities and to identify dietary problems in nursing homes. Approximately three-fourths (74%) of the 43 respondents reported insufficient time at nursing homes, although all met or exceeded state consulting time requirements. Role functions receiving the greatest time investments were in the categories of foodservice management and nutrition care. Resident nutrition care issues were often rated as major problems. Dietitians' perceptions of nutrition care problems and inadequacy of time to perform role functions indicate a need to re-evaluate priorities for role performance and to obtain increased service hours. Methods to increase consulting time should include effective marketing of services and involvement in legislative and regulatory processes.     

Optimization of a Human Papillomavirus-Specific Enzyme-Linked Immunosorbent Assay

A strategy was developed for the control, standardization, and critical evaluation of an enzyme-linked immunosorbent assay (ELISA) for the detection of human papillomavirus-specific immunoglobulin G in human sera. Control human sera, polyclonal animal sera, and monoclonal antibodies were used to establish optimal assay parameters, including antigen coating, serum dilutions, and criteria for daily reproducibility, monitoring, and rejection of assays. Three evaluation techniques were used in parallel to define an optimal cutoff absorbance value that yields greater than 93% sensitivity and 98.5% specificity in the assay's ability to discriminate positive and negative control sera. This strategy provides an optimal method by which to determine cutoff absorbance values for ELISA.