Gastrointestinal metastasis in hepatocellular carcinoma: radiological and endoscopic studies of 11 cases

BACKGROUND

From October 1990 to January 1999, 11 of 2237 hepatoma patients at our hospital had gastrointestinal tract metastasis. We describe the radiological and endoscopic features, clinical course and prognoses of those patients.

METHODS

All patients were male. Six patients were hepatitis B carriers, and cirrhosis was noted in eight patients on admission. We reviewed all available radiological, endoscopic and pathological features.

RESULTS

The commonest clinical presentation was frank gastrointestinal bleeding. Histological proof of gastrointestinal involvement was seen in six patients. Endoscopic features included ulcerative tumours mimicking advanced gastric carcinoma (43%) and submucosal tumours (29%). The sites of organ involvement were stomach (five), duodenum (two), colon (three) and duodenum and colon (one). Direct invasion by a contiguous neoplasm was the major route of gastrointestinal tract metastasis. Portal vein thrombosis may be the key point of haematogenous spread to other sites.

CONCLUSIONS

The prognosis in these patients was extremely poor. Almost all patients died within 5 months if no further aggressive management was performed. Surgical intervention may be the optimal choice for palliative treatment of HCC with gastrointestinal tract involvement.

Impact of Helicobacter pylori eradication on the development of MALT, gland atrophy and intestinal metaplasia of the antrum

BACKGROUND

Chronic Helicobacter pylori infection leads to the development of mucosa-associated lymphoid tissue (MALT), gland atrophy, intestinal metaplasia, and in certain individuals, gastric lymphoma and adenocarcinoma. We conducted a prospective study to determine the effect of H pylori eradication on the development of MALT, gland atrophy and intestinal metaplasia.

METHODS

From July 1995 to October 1996, 63 consecutive patients with H pylori-associated peptic ulcer disease were enrolled in a bacterial eradication trial. The grade of MALT and the degree of gastritis of the antrum were assessed using Wotherspoon's scale and the Sydney system before treatment, and at eight weeks and one year after H pylori eradication therapy.

RESULTS

During the study period, 43 patients received complete follow-up. In the patient group with eradication failure (n = 22), MALT score was significantly decreased at the end of the eighth week (p < 0.05) but returned to the initial level by one year of follow-up. There were no changes in the scores for inflammation, neutrophil activity, gland atrophy or intestinal metaplasia at the end of the eighth week and at one year following H pylori eradication therapy. In contrast, there was a marked reduction in the MALT, inflammation, and activity scores at eight weeks (p < 0.01, < 0.05 and < 0.05, respectively) and one year after treatment (p < 0.05, < 0.001 and < 0.001, respectively) in the patient group with successful eradication (n = 21). However, no significant changes in gland atrophy and intestinal metaplasia were observed during the follow-up period.

CONCLUSIONS

Eradication of H pylori leads to regression of MALT in the stomach, but the degrees of gland atrophy and intestinal metaplasia remain unchanged, even after one-year of follow-up.

Impact of bacterial eradication on the cell proliferation and p53 protein accumulation in Helicobacter pylori-associated gastritis

BACKGROUND

This study investigates the cell proliferation and the expression of p53 protein in Helicobacter pylori (H. pylori)-associated gastritis and assesses the effect of bacterial eradication on these epithelial factors.

MATERIAL AND METHODS

Seventy-nine patients with H. pylori-associated gastritis were randomized into the control group (n = 38) and anti-H. pylori group (n = 41). Each patient received endoscopic examinations with gastric biopsy before and 8 weeks after the treatment. The specimens from gastric antrum were immunostained for monoclonal antibodies against the proliferating cell nuclear antigen (PCNA) and p53 protein.

RESULTS

In the control group, the total labeling index (L.I.) of PCNA and the positive index (P.I.) of p53 in the whole foveolar epithelium were unchanged after treatment. In the anti-H. pylori group, 35 of 41 cases (85.3%) achieved eradication of H. pylori. Amongst the H. pylori-eradicated cases, the total L.I. of PCNA in the whole foveolar epithelium did not meaningfully alter after H. pylori elimination (p > 0.05). However, a significant reduction of L.I. was observed in the middle compartments of the gastric pits (before vs. after treatment: 14.0 vs. 7.3, p < 0.05). With regard to the p53 expression, the P.I.s were significantly decreased in the whole foveolar epithelium (before vs. after treatment: 0.57 vs. 0.17, p < 0.05) and in each compartment of the gastric pits (before vs. after treatment: [upper compartment]: 0.34 vs. 0.15, p < 0.05; [middle compartment]: 0.67 vs. 0.23, p < 0.05; [lower compartment]: 0.71 vs. 0.20, p < 0.05) after eradication of H. pylori.

CONCLUSIONS

Bacterial eradication reverses the hyperproliferating status of the foveolar epithelium in patients with H. pylori gastritis and leads to a decrease in p53 accumulation in the epithelial cells.

Vertebral deformity in chinese men: prevalence, risk factors, bone mineral density, and body composition measurements

The prevalence and risk factors for vertebral deformity were studied in 396 community-dwelling Chinese men aged 70-79 years. Anterior to posterior (H(a)/H(p)), middle to posterior (H(m)/H(p)) and posterior to posterior (H(p)/H(p - 1) or H(p)/H(p + 1)) ratios from T5 to L5 were derived from lateral spine X-ray films, using standardized digitization methods. Using values of 3 standard deviations (SD) or more below the mean and 4 SD or more below the mean as the cutoff, 16% and 7% of these men, respectively, were deemed to have one or more deformed vertebra. Heavy cigarette smoking, heavy alcohol consumption, and working as a heavy manual worker were risk factors for vertebral deformity. Men with severe vertebral deformity (VHR < mean - 4 SD below mean) had much lower body weight, fat mass, and bone mineral density (BMD) than controls. The odds ratios for severe vertebral deformity was 9.9 (95% CI 2.1-45.7) in the lowest quartile of femoral neck BMD.

A control study of the cutaneous side effects of chronic lithium therapy

BACKGROUND

To assess the nature and prevalence of skin disorders among psychiatric patients on chronic lithium therapy and to compare them with patients on other psychotropic medications.

METHOD

51 patients on lithium and 57 patients on other psychotropics were recruited. Dermatological assessment included a semi-structured questionnaire and clinical examination of the subjects by two dermatologists who were blind to the psychiatric diagnosis and treatment. Secondary cutaneous reaction was defined as skin eruption that developed or deteriorated after commencement of psychiatric medication.

RESULTS

Lithium treated patients developed significantly more secondary cutaneous reactions than the control group. This applied particularly to acne and psoriasis. Male patients on lithium were more likely to be affected than female patients.

CONCLUSION

Lithium aggravates or triggers cutaneous conditions that are characterized by the pathological findings of neutrophilic infiltration. Since these cutaneous problem can be distressing to patients and may affect medication compliance, there should be heightened attention to skin problems in patients receiving lithium treatment.

Long-term effect of large biliary endoprostheses in high-risk surgical patients with irretrievable common bile duct stones

BACKGROUND

Endoscopic sphincterotomy and basket extraction are currently used to remove bile duct stones, with a duct clearance rate of 85% to 90%. A biliary endoprosthesis (stent) is an alternative method to treat difficult cases, especially high-risk surgical patients. The aim of this study was to investigate the long-term effect of biliary endoprostheses in patients with irretrievable common bile duct stones.

METHODS

From December, 1990, to November, 1998, 546 patients were referred to the Veterans General Hospital-Kaohsiung for endoscopic removal of common bile duct stones. Of them, 12 received long-term biliary endoprosthesis because endoscopic removal or surgery was not suitable. Large-caliber stents (> 10 French) were inserted into 12 patients (5 women and 7 men, mean age, 78.4 years) and they were followed up with regular clinical visits. Quantitative cholescintigraphy was performed in four patients to evaluate biliary emptying after liver function returned to normal.

RESULTS

No early complications from stent insertion occurred and a satisfactory resolution of jaundice, pain and fever were noted in all patients. One patient had repeated cholangitis due to stent occlusion and five died from unrelated causes. The median effective period of stent placement was 11 months (range, 1-38 months). Quantitative cholescintigraphy revealed delayed biliary drainage in four patients despite an absence of symptoms after their liver function returned to normal.

CONCLUSIONS

Large-caliber stents are a safe and effective treatment for long-term palliation in high-risk patients with retained common bile duct stones.

The clinical spectrum of rudimentary meningocele

Rudimentary meningocele is rare, only 50 cases having been reported. Clinically it may simulate dermoid cyst, lipoma, or nevus sebaceous. We present two cases of this uncommon condition, each with its own unique clinical features.

The Soft X-ray Scanning Photoemission Microscopy Project at SRRC

The Synchrotron Radiation Research Center (SRRC) and the Institute of Atomic and Molecular Sciences (IAMS) have initiated a project to construct a scanning photoelectron spectromicroscopy end station at SRRC (SRRC-SPEM). High-brightness soft X-rays will be provided by the U5 undulator beamline. Zone-plate-based soft X-ray optics will be used to focus the beam to form the microprobe. A hemispherical sector analyser with multichannel detection capability will collect the photoelectrons. A total of up to 32 images can be acquired concurrently. The apparatus is also equipped with a sample distribution system for in situ sample preparation and characterization in conjunction with other surface spectroscopic techniques.

The reliability of upper limb anthropometry in older Chinese people

OBJECTIVE

To evaluate the validity of the Durnin-Womersley equations and to derive our local predictive equations for body fat from upper limb skinfold thicknesses in older Chinese people in Hong Kong. To evaluate the validity of mid-arm circumference and corrected arm muscle area in predicting lean tissue mass in the same population.

DESIGN

Comparison of fat percentages predicted by Durnin-Womersley (D-W) equations with those estimated by Dual energy X ray absorptiometry (DXA). Predictive equations derived from regression between upper limb skinfold thicknesses and fat percentages estimated by DXA were similarly evaluated in internal and external validation groups. Mid-arm circumference (MAC) and corrected arm muscle area (CAMA) were correlated with the limb lean tissue mass, body lean tissue mass and fat percentage.

SUBJECTS

354 female and 263 male, apparently well, community dwelling subjects, aged 69-82 y; of which 40 subjects of each sex were randomly selected from the study population for internal validation of the local predictive equations; 60 female and 33 male hospital medical outpatients, aged 61-87 y, were recruited for external validation.

MEASUREMENTS

Triceps and biceps skinfold thicknesses, mid-arm circumference, body mass index, fat percentages, limb and whole body lean tissue masses estimated by Hologic QDR-2000 bone densitometer.

RESULTS

Fat percentages calculated by D-W equations were significantly different from those estimated by DXA (average difference -2.4 (s.d. 4.8)% and +2.1 (5.2)% in females and males respectively). The corresponding differences for our local predictive equations were not significant (-0.9 (4.7)% and -0.5 (5.0)% in females and males respectively). There was a trend of under-estimation of body fat with increasing fatness. In the hospital medical outpatients, there was a significant difference between fat percentages predicted by our equation and those by DXA in female (-2.9(5.3)%), but not in male (+0.3(4.3)%) subjects. In males, MAC correlated with limb and body lean tissue masses as well as with fat percentage (r = 0.60, 0.68, 0.65 respectively). CAMA correlated similarly well with lean tissue masses but was more independent of fat percentage (r = 0.61, 0.65, 0.44 respectively). In females, both MAC and CAMA correlated poorly with limb and body lean tissue masses. Moreover, MAC correlated well with fat percentage (r = 0.80).

CONCLUSION

Upper limb skinfold thicknesses measurement is a valid means of predicting body fat in older Chinese people. Local predictive equations were more reliable that D-W equations. They were, however, subject to errors at the extreme ends of body fatness and in the presence of disease. In older females, MAC and CAMA were not reliable in predicting lean tissue mass, but MAC could be used to predict fat percentages. In older males, CAMA was more reliable than MAC in predicting lean tissue mass.

Body composition and bone mineral density of Chinese women with vertebral fracture

This study was designed to compare the body composition and bone mineral density measurements (BMD) in Chinese women with vertebral fracture and normal controls. A total of 400 community dwelling Chinese women aged 70-79 years old were studied. Vertebral height ratios were calculated from lateral thoracic and lumbar spine X-rays and subjects were classified into definite cases (n = 122), doubtful cases (n = 138) and normal controls (n = 140). Bone mineral density and body composition measurements were made by dual X-ray densitometry. The height, fat mass, lean mass, and BMD at all sites were significantly lower in patients with definite fracture than normal controls. Nevertheless, BMD at the hip was more predictive of vertebral fracture than BMD at the spine, the odds ratio in the lowest quartile of hip BMD being 3.8 (95% C.I. = 1.3 to 10.9). Finally, the extent of spinal deformity was poorly predicted by a combination of the anthropometric and BMD measurements, as only 12% of the total variance in TD1 was accounted for.

Aggressive polyfibromatosis: a 10 year follow-up

Polyfibromatosis syndrome is a condition characterized by the occurrence of several cutaneous fibrotic conditions including Dupuytren's contracture and keloid formation. A 10 year follow-up of a patient with an aggressive type of polyfibromatosis associated with erosive arthropathy is presented. The underlying pathogenesis and management of this uncommon condition is discussed.

Normal ranges for vertebral height ratios and prevalence of vertebral fracture in Hong Kong Chinese: a comparison with American Caucasians

We have established the normal ranges for vertebral height ratios and studied the prevalence of vertebral fracture in 481 Chinese women aged 70-79. Our results were compared with those of an American study with a similar methodology. Lateral spine radiographs centered at T8 and L3 were taken, and the anterior, middle, and posterior vertebral heights of each vertebra from T5 to L4 were measured. The means and standard deviations (SDs) of the anterior to posterior, middle to posterior, and posterior to posterior vertebral height ratios were derived after trimming the extreme values from the distribution. The Chinese had smaller vertebral size than the American Caucasians at all levels. Moreover, the anterior to posterior vertebral height ratios were consistently smaller in the Chinese than in the Americans from T10 onward. The means of other vertebral height ratios in the Chinese were similar to the American Caucasians, but the SDs were greater in the Chinese. The prevalence of vertebral fracture was 29% in the Chinese and 25% in the American Caucasians if a cut-off of 3 SD below the mean for vertebral height ratios was used. We conclude that population-specific means and SD should be used for defining vertebral fracture and that the prevalence of vertebral fracture is similar in Hong Kong Chinese and American Caucasians.

Thyrotoxic periodic paralysis in a Chinese population

We retrospectively evaluated the characteristics of adult patients admitted with thyrotoxic hypokalaemic periodic paralysis in Hong Kong. From 1984 to 1993, 45 Chinese adult patients were admitted with acute limb weakness, plasma potassium < or = 3.5 mmol/l and thyrotoxicosis confirmed by laboratory investigations. All but one were male. Seventy-five percent of attacks occurred between 9pm and 9am. Half of the attacks occurred between July and October (49.1%), most commonly in August (20%). Mean (+/- SEM) plasma potassium on admission was 2.17 +/- 0.08 mmol/l (range 1.1-3.5). In 15 episodes (27.3%), plasma potassium on recovery exceeded 5.0 mmol/l, while in three episodes (5.5%), potassium exceeded 6.0 mmol/l. No patient had a positive family history of thyrotoxic periodic paralysis. Only 28.9% had a known history of thyrotoxicosis before their first presentation with periodic paralysis. Twenty-seven (60%) had clinical evidence of thyrotoxicosis. Although all were biochemically thyrotoxic, 11.4% had only a mild degree of thyrotoxicosis (suppressed thyroid-stimulating hormone, high free thyroxine, but normal free triiodothyronine). One quarter of the patients had a normal erythrocyte zinc concentration, indicating either a short history of thyrotoxicosis or transient thyrotoxicosis. The diagnosis of thyrotoxic hypokalaemic paralysis should always be considered in Chinese patients with acute muscle weakness, especially in young males. Absence of clinical thyrotoxicosis does not exclude the diagnosis. Plasma potassium should be monitored carefully during treatment to prevent rebound hyperkalaemia.

Dietary calcium intake, physical activity and the risk of vertebral fracture in Chinese

To study the relationship between dietary calcium intake, load-bearing activity, reproductive factors, anthropometric factors and vertebral fracture in Chinese, a case-control study was carried out on 481 women (aged 70-79 years) who lived in three housing blocks under the Geriatric Priority Housing Scheme in Shatin, Hong Kong. Lateral spine radiographs were taken from the T4 to L4 level. Definite and doubtful vertebral fractures were diagnosed when any of the three vertebral height (anterior to anterior, middle to posterior and posterior to posterior) ratios was 3 SD and 2-2.99 SD below the mean respectively. Women with one or more definite fractures were classified as definite cases, those with one or more doubtful fractures were classified as doubtful cases, and the rest as controls. The mean dietary calcium intake and load-bearing activities were obtained by interview, using a structured questionnaire. Detailed information on cigarette smoking, alcohol consumption and reproductive factors was also obtained. The grip strength, body weight and height were measured. Doubtful cases were found to differ little from the controls in their lifestyle and anthropometric factors. The odds ratio (OR) for being a definite case was 2.1 (95% CI = 1.1-3.9) when the dietary calcium intake was in the lowest quartile. The OR was 1.8 (95% CI = 0.8-4.4) for subjects who walked or exercised outdoors for less than an hour a day. Giving birth to or breast-feeding three children or more was protective against definite fracture. The definite cases were significantly lighter and shorter than controls; they also had a weaker grip strength. It is concluded that a low dietary calcium intake was significantly associated with an elevated risk of vertebral fracture, while the effect of infrequent load-bearing activity was uncertain. Giving birth to or breast-feeding three or more children was protective against vertebral fracture in our population.

A patient with co-existing bronchial carcinoid tumour and bilateral phaeochromocytoma

We report a 31-year-old Chinese man with bronchial carcinoid tumour and bilateral phaeochromocytoma. His sister also gave a history of bilateral carotid body paraganglioma. This case demonstrates the importance of screening for other endocrine disorders in patients with foregut carcinoid tumours.

Routine gamete intrafallopian transfer (GIFT): a highly successful option for treatment of non-tubal infertility

Gamete intrafallopian transfer (GIFT) is increasingly accepted as a realistic alternative to in vitro fertilization (IVF), or intrauterine insemination (IUI) for treatment of non-tubal infertility. The lack of information on fertilization capacity of the gametes, the greater cost relative to IUI, and the partly unsubstantiated claims of higher success rates, caused us some concern with the readiness with which GIFT had been accepted as a standard infertility treatment. So we undertook a provisional GIFT programme with these considerations in mind, and we report on the first 91 GIFT cycles performed in our clinic. Sixty of the patients (62 cycles) treated suffered from idiopathic infertility, 12 from minimal endometriosis, 9 from male factor infertility, and 8 from ovulatory dysfunction. An initial clinical pregnancy rate of 41% (38/91) was achieved; pregnancy loss was 23% (9/38), giving a continuing pregnancy rate of 32% (29/91). Given this undeniably encouraging result, and the potential for diagnostic IVF, embryo freezing, and ovum donation with surplus oocytes collected from this GIFT programme, we now have adopted GIFT permanently as a treatment to complement our IVF and IUI programmes.

Fallopian replacement of eggs with delayed intrauterine insemination (FREDI): an alternative to gamete intrafallopian transfer (GIFT)

This report contains details of what is the first group of patients with nontubal infertility to undergo fallopian replacement of eggs with delayed intrauterine insemination (FREDI). Twenty-three patients suffering from idiopathic or immune infertility, polycystic ovarian disease (PCOD), or mild endometriosis underwent follicular stimulation with human menopausal gonadotropin and/or pure follicle-stimulating hormone plus human chorionic gonadotropin prior to laparoscopic pickup of eggs of varying maturity. Eggs without spermatozoa were transferred at the time of laparoscopy. Subsequent high intrauterine insemination (IUI) of washed spermatozoa at a time when egg maturation within the tubes was judged to be complete enabled a cohort of fully capacitated spermatozoa to meet fully mature eggs in a totally physiological manner. Eight clinical pregnancies arose from this group, one healthy, male infant has been delivered, and four pregnancies remain ongoing. Although based on a small population of patients, it does seem that in vivo egg maturation following replacement in the fallopian tube is an effective alternative to in vitro maturation and, with the increased control over timing of egg insemination, leads us to propose FREDI as a flexible new therapeutic approach for the treatment of nontubal infertility.

Obesity as a risk factor in drug-induced organ injury. III. Increased liver and kidney injury by furosemide in the obese overfed rat

Effects of the diuretic drug furosemide were examined in obese animals to evaluate the hypothesis that organ damage by reactive drug metabolites may be potentiated by this disease. Obese overfed Sprague-Dawley rats that were treated ip with 450 mg/kg furosemide on the basis of total body mass suffered a 58% mortality rate over 24 h. This contrasted with 0% mortality in animals of normal body mass. On the basis of median histopathology scores, organ necrosis was judged to be greater in the liver (2+) and kidneys (1+) of obese rats than in the liver (1+) and kidneys (less than 1+) of normal controls (p less than 0.05). Obese animals demonstrated a fourfold rise in fat mass over controls. The low solubility of furosemide in lipid makes it probable that aggravated drug toxicity in obese rats dosed to total body mass resulted in part from elevated furosemide concentrations in lean body mass. In a subsequent study designed to minimize this possibility, furosemide was administered on the basis of fat-free body mass to equalize initial drug exposure in obese and control rats. Even with this downward dosage adjustment, obese animals suffered increased hepatic necrosis (median score of 2+ versus 0 in treated controls), greater impairment of renal function (plasma creatinine concentration of 2.41 mg/dl versus 0.96 mg/dl in treated controls), and more extensive enzymuria (enzyme excretion 175-300% more elevated than in treated controls). In conclusion, obese rats appear to be at increased risk of furosemide-induced liver and kidney injury due to at least two factors: (1) increased exposure of target organs in lean body mass to furosemide when the dosing of this poorly lipophilic drug was based on total body mass, and (2) increased susceptibility of target organs in lean body mass to furosemide injury when dosing was adjusted downward to reflect fat-free body mass and to equalize initial drug exposure.

Pregnancies from fallopian replacement of immature eggs with delayed intrauterine insemination

Gamete intrafallopian transfer requires that a woman should not only have patent tubes but should also have had mature eggs collected for replacement. Eggs must be collected as close to ovulation as possible, to give them a good chance of fertilizing upon replacing them directly into the tubes with the spermatozoa. Preliminary results from three patients who received Fallopian replacement of immature eggs followed by delayed intrauterine insemination indicate that maturation of eggs can occur in vivo in the Fallopian tubes. Intrauterine insemination at a later time when the eggs were judged to be mature has given rise to two pregnancies from the three patients with whom this procedure was adopted.

Comparative study of combined GIFT and IVF-ET with GIFT alone

Twenty-eight couples with unexplained infertility, or with suboptimal spermatozoa were divided into two groups. One group underwent gamete intra-Fallopian transfer (GIFT), and the other had combined GIFT and in-vitro fertilization--embryo transfer (IVF-ET) (GET). There was a marked difference in pregnancy rates between the two groups, with the pregnancy rate surprisingly being less in the combined GET group; 10% for GET, as compared with 39% for GIFT alone. The results suggest that GIFT and IVF-ET are incompatible. Differences in the pregnancy rates may be explained by limitations in implantation, whereby the embryo-endometrium interaction that allows for implantation and continued embryonic development has a 'single event capacity', and once this interaction is initiated, the 'implantation window' is closed to other embryos that may arrive later in the uterus.

Comparison of nitrosocarbaryl and carbaryl: in vitro effects on hepatic microsomal aryl hydrocarbon hydroxylase, aminopyrine N-demethylase, epoxide hydrolase and cytosolic glutathione-S-transferase

The Comparative effects of nitrosocarbaryl and carbaryl on rat hepatic microsomal aryl hydrocarbon hydroxylase, aminopyrine-N-demethylase, epoxide hydrolase and cytosolic glutathione-S-transferase in vitro was investigated. The effects of nitrosocarbaryl on these hepatic drug metabolizing enzyme systems differ markedly (P less than 0.05) from carbaryl. Nitrosocarbaryl was more potent and had much higher inhibitory effect than carbaryl on microsomal aryl hydrocarbon hydroxylase, aminopyrine N-demethylase, epoxide hydrolase and cytosolic glutathione-S-transferase. Inhibition of these enzyme systems by nitrosocarbaryl was dose-dependent. In microsomes, nitrosocarbaryl showed a significant (P less than 0.001) inhibition of aryl hydrocarbon hydroxylase and aminopyrine N-demethylase as compared with the control when the concentration of nitrosocarbaryl added was above 1 X 10(-5) M. The I50 values were 1.8 X 10(-5) M and 3.5 X 10(-5) M, respectively. Nitrosocarbaryl inhibited epoxide hydrolase activity gradually up to 18% at the range of concentration studied (1.3 X 10(-3) M - 1.2 X 10(-2) M) and showed a significant (P less than 0.001) inhibition at the concentration of 1.2 X 10(-2) M. Nitrosocarbaryl at concentrations above 1.6 X 10(-4) M showed a significant (P less than 0.001) inhibition of cytosolic glutathione-S-transferase activity with an I50 value of 3.8 X 10(-4) M. By Contrast, carbaryl failed to inhibit aryl hydrocarbon hydroxylase at concentrations below 3 X 10(-4) M. The pesticide inhibited the enzyme activity only by 20% at the maximum concentration studied (6 X 10(-4) M).(ABSTRACT TRUNCATED AT 250 WORDS)

Identification of iodoamino acids in the plasma and bile of brook trout, Salvelinus fontinalis (Mitchill)

Thyroxine was the main labelled iodocompound consistently detected by thin-layer chromatography in plasma and bile of starved TSH (thyroid-stimulating hormone) - treated brook trout previously injected with radioiodide. Failure to detect 3,5,3′-triiodo-L-thyronine and iodotyrosines contrasts with results of the few previous studies on circulating iodocompounds in teleosts.No labelled iodoamino acids were detected in plasma of trout held under a variety of conditions but not treated with TSH.