Didecanoyl phosphatidylcholine is a superior substrate for assaying mammalian phospholipase D

Phospholipase D (PLD) activity in crude or solubilized membranes from mammalian tissues is difficult to detect with the current assay techniques, unless a high radioactive concentration of substrate and/or long incubation times are employed. Generally, the enzyme has to be extracted and partially purified on one column before easy detection of activity. Furthermore, PLD activity in cultured cells can only be detected by the available assay techniques in the presence of guanosine 5'-[gamma-thio]-triphosphate (GTP[S]) and a cytosolic factor [usually ADP-ribosylation factor (Arf)]. In this paper we report that the use of didecanoyl phosphatidylcholine (C10-PC) in mammalian PLD assays considerably increases the detection limit. C10-PC was compared with the commonly used dipalmitoyl phosphatidylcholine (C16-PC) as a substrate for PLD activity from membranes of human neutrophils, human placenta and pig brain, and from placental cytosol. C10-PC was superior to C16-PC by a factor of 2-28 depending on assay conditions and tissue, and it allowed the detection of GTP[S]-and Arf-stimulated PLD activity without addition of phosphatidylinositol 4,5-bisphosphate.

The effect of sustained release boli with ammoniumiron(III)-hexacyanoferrate(II) on radiocesium accumulation in sheep grazing contaminated pasture

Sustained release boli with the cesium binder ammonium iron(III)-hexacyanoferrate(II) (AFCF) were tested under practical conditions for sheep grazing on pastures contaminated with radiocesium (134Cs+137Cs) from the Chernobyl fallout. Two types of AFCF boli were developed: boli without a protective surface coating intended to last 4-8 wk; and boli coated by a wax-mixture with an extended duration of 10-12 wk. From 1989 to 1993 we measured the effect of wax-coated and uncoated boli administered at various times during the grazing season to a total of 3,248 animals. Reductions in radiocesium levels in meat of sheep were measured by in vivo monitoring. Administration of AFCF boli without a wax-coating reduced the mean radiocesium levels in lambs by 43-75% over a 4-8 wk period, and administration of the wax-coated AFCF boli reduced the mean radiocesium levels by 48-65% over a 9-11 wk period. The coefficients of variation in meat radiocesium levels were similar in treated and control groups at the end of the observation period, showing that the reduction of meat radiocesium values was homogenous throughout the treated groups. The boli giving sustained release of AFCF is a labor-saving and cost effective countermeasure for sheep grazing radiocesium contaminated pastures.

[CT scanning in suspected ileus or pneumoperitoneum]

In this prospective survey of six months duration, 66 consecutive patients referred for plain abdominal views on suspicion of bowel obstruction or pneumoperitoneum had supplementary abdominal CT-scans performed. Thirty-one patients underwent surgery. Seventeen suffered from bowel obstruction, one patient had both bowel obstruction and pneumoperitoneum and three had pneumoperitoneum. CT-scans correctly demonstrated all cases of bowel obstruction or pneumoperitoneum. The plain abdominal views resulted in one false negative diagnosis of bowel obstruction and one false negative diagnosis of pneumoperitoneum. Ten of the operated patients had neither bowel obstruction nor pneumoperitoneum. In nine of these cases this was in accordance with the interpretation of both CT and plain abdominal views. Both modalities resulted in one false positive diagnosis of bowel obstruction. In most cases we find no difference between the two modalities in demonstrating or excluding bowel obstruction or pneumoperitoneum. We therefore conclude that the plain abdominal X-ray should be the primary examination on suspicion of bowel obstruction or pneumoperitoneum. We recommend CT-scanning in cases with clinical suspicion of bowel obstruction or pneumoperitoneum and no obvious pathology on the plain abdominal X-ray.

[The use of coercion at psychiatric departments for adults, Hillerød hospital. A descriptive study of the period 10 January 1991-31 August 1992]

The study describes the type and amount of coercion used during 11 months of 1992. Four hundred and fourty-one cases were included. Young patients i.e. 10 to 29 years old, demented patients and patients suffering from organic psychoses were, overall, more often subjected to coercive measures. When looking at each type of coercion separately, it was found that detainment, compulsive treatment and fixation were especially used on the young and on patients suffering from schizophrenia. However, fixation used as a protective measure was mainly used on the demented and the 60 to 79 year-old patients.

Interrelationships between diagnosed asthma, asthma-like symptoms, and abnormal airway behaviour in adolescence: the Odense Schoolchild Study

BACKGROUND

The diagnosis of asthma is based on several characteristics including symptoms and suitable tests of airway lability. However, it is neither clear to what degree various tests and symptoms identify the same subjects, nor how these characteristics are best combined to diagnose asthma. The interrelationships between physician-diagnosed asthma, asthma-like symptoms, and abnormal airway function, as defined by four commonly used tests, have therefore been assessed.

METHODS

A population based sample of 495 Danish schoolchildren aged 12-15 years, comprising 292 randomly selected subjects and 203 subjects considered at risk of having or developing asthma, was examined. Symptoms and background information were recorded by questionnaire. The test panel consisted of baseline forced expiratory volume in one second (FEV1%), provocation with treadmill exercise (EXE) and with inhaled methacholine (PD15), and monitoring of peak expiratory flow (PEF) twice daily for two weeks.

RESULTS

The sensitivity for diagnosed asthma was highest for PD15 followed by PEF monitoring, whereas specificity for asthma or asthma-like symptoms was marginally higher with the other two tests. Most symptomatic subjects with any positive test were identified by PD15 alone (75%) or in combination with PEF monitoring (89%). PEF variability was more susceptible to treatment with inhaled steroids than the PD15 index. Although inter-test agreement was weak (kappa < 0.40 for all pairs), significant associations were found between PD15 and EXE, PEF and EXE, and FEV1% and PD15.

CONCLUSIONS

The agreement between the four tests was weak. In particular, PEF variability and methacholine responsiveness seem to identify different varieties of airway pathophysiology. The combined use of methacholine provocation testing and PEF monitoring may be helpful as an epidemiological screening tool for asthma.

Immunohistochemical and quantitative changes in salivary EGF, amylase and haptocorrin following radiotherapy for oral cancer

Epidermal growth factor (EGF), amylase and haptocorrin are molecules produced in the salivary glands. The aim of the present study was to determine immunohistochemical and quantitative alterations in EGF as compared with haptocorrin and amylase following radiotherapy for oral cancer. Changes in the salivary secretion of EGF are of interest because of the importance of EGF in mucosal regeneration. Immunohistochemical studies on normal tissue from parotid and submandibular glands have demonstrated EGF in the serous acini with a tendency to single cell expression in the parotid gland. Amylase has been found in the serous acini of both the submandibular and parotid glands. Haptocorrin was localized in the duct system of both glands. In the submandibular glands with radiotherapy induced sialoadenitis only very few acini with weak or no staining for EGF and amylase were demonstrated, while no changes were observed in the staining for haptocorrin. Analysis on stimulated whole saliva samples collected from 20 healthy individuals and from 20 patients prior to, and 1, 2 and 3 weeks following radiotherapy showed significant reduction in salivary contents of EGF and amylase after treatment as expressed per g protein (p < 0.0002). The salivary content of haptocorrin increased significantly after treatment (p < 0.002). These alterations may be explained by the different cellular sites of the molecules studied, the serous acini being more sensitive to ionising radiation than the duct system. The concentration of EGF in saliva before treatment was significantly higher in patients than in the control group (p < 0.02), which may indicate that the tumors induce increased secretion of salivary EGF, or alternatively that the oral tumors contribute with EGF to the saliva. In conclusion we have demonstrated a reduction in the mitogenic peptide EGF both immunohistochemically and quantitatively following irradiation for oral cancer, results which may contribute to the understanding of the clinical signs of mucositis.

Differential phospholipid-labeling suggests two subtypes of phospholipase D in rat Leydig cells

The aim of the present study was to compare the transphosphatidylation activity of phospholipase D (PLD) under different substrate labeling conditions, in order to investigate whether PLD in rat Leydig cells exhibited any substrate preferences for the alkyl- or acyl-form of phosphatidylcholine (PtdCho). The [3H]phosphatidylethanol formation in response to 4 beta-phorbol 12-myristate 13-acetate (PMA), sphingosine, or Ca(++)-ionophore A23187, was lower when Leydig cells were labeled with 1-O-[3H]alkyl lysoPtdCho compared with the responses when [3H]myristic acid was employed. In contrast, the results for the receptor agonists (vasopressin, bradykinin, and lysophosphatidic acid), using the two labels, showed more consistency. Thus, the PLD-activity induced by PMA, sphingosine, or A23187 has a more selective substrate range (i.e. mainly acyl-linked PtdCho) than the PLD-activity stimulated via a receptor. Our data suggests the existence of PLD isozymes that differ with respect to substrate specificity and activation mechanisms.

Glutamate stimulates the formation of N-acylphosphatidylethanolamine and N-acylethanolamine in cortical neurons in culture

The formation of anandamide (N-arachidonoylethanolamine), N-acylethanolamine, and N-acylphosphatidylethanolamine was studied in primary cultures of rat cortical neurons. The cells were incubated for 22 h with [14C]ethanolamine, [U-14C]arachidonic acid, [3H]arachidonic acid, [32P]phosphate, [14C]stearic acid, or [3H]myristic acid. The lipids from the cells and media were separated by thin layer chromatography. [14C]Ethanolamine labelling revealed two compounds (I and II), which on different thin layer chromatography systems migrated as N-acylethanolamine (0.06-0.55% of total radioactivity) and N-acylphosphatidylethanolamine (0.66-6.49% of total radioactivity), respectively. Compound II was also labelled with [32P]phosphate, and radioactive fatty acids. Treatment of compound II with phospholipase D (Streptomyces chromofuscus) resulted in two compounds, one comigrating as phosphatidic acid and the other as N-acylethanolamine. Compound I could be labelled with [14C]stearic acid and [3H]myristic acid, but not with [3H]- or [14C]arachidonic acid. Exogenous [3H]anandamide was metabolised with a t1/2 of 2.6 h. The labelling of the two compounds identified as N-acylethanolamine and N-acylphosphatidylethanolamine were more pronounced the older the culture. The neurotoxic amino acid, glutamate, stimulated within 2 h dose-dependently (ED50 = 40 microM) the formation of both compounds. It is suggested that N-acylethanolamine and N-acylphosphatidylethanolamine are formed in relation to the cytotoxicity induced by glutamate, and that these compounds may be markers of neurotoxicity. We could not detect any formation of anandamide using radioactive arachidonic acid.

Age-related changes in the percentage of oleate in adipose tissue of male and female Fischer rats

Fischer 344 rats showed sex difference in the percentage of oleate in lipids of the omental adipose tissue (Thorling, E.B. and Overvad, K. (1994) Nutr. Res. 14, 569-576). The development of this difference was studied with respect to time in rats maintained on laboratory chow, from the age of 3 weeks to 20 weeks. From the age of 3 weeks to 5 weeks the percentage of oleate increased slightly in both sexes. From the age of 5 weeks to 13 weeks the percentage (mean +/- S.D., n = 5) increased further in the female rats from 24.8 +/- 0.6% to 27.6 +/- 0.6%, whereas in the male rats it dropped from 22.9 +/- 0.4% to 20.2 +/- 0.6% at the same time points, respectively. In adult rats, age 20 weeks, the percentage of oleate was 28.6 +/- 0.3% and 19.6 +/- 0.5% for females and males, respectively. Castrated males partly maintained their juvenile level, being 21.1 +/- 1.1% fourteen weeks after castration at the age of 6 weeks. Oestrogen injections twice a week to the castrated rats increased their oleate percentage within the same period to 23.4 +/- 0.3%, partly reflecting the increase observed in the female rats. Stearic acid showed similar but less pronounced changes. The ratio oleic acid/stearic acid was constantly higher in the female than in the male rats, and this difference increased with age. The results of the present study suggest that these changes in percentage of oleate in adipose tissue lipids may partly have been caused by an effect of sex steroids on the delta-9-desaturase.

Characterization and partial purification of phospholipase D from human placenta

We report the existence in the human placenta of a phosphatidylcholine-hydrolyzing phospholipase D (PLD) activity, which has been characterized and partially purified. Triton X-100 effectively solubilized PLD from the particulate fraction of human placenta in a dose-dependent manner. However, Triton X-100 caused decreasing enzyme activities. Maximum transphosphatidylation was obtained with 2% ethanol. The enzyme was found to have a pH optimum of 7.0-7.5 and an apparent Km of 33 mol% (or 0.8 mM). Ca2+ and Mg2+ was not required for the enzyme activity. Addition of phosphatidyl-4,5-bisphosphate, but not phosphatidylethanolamine, to the substrate mixture gave rise to a pronounced dose-dependent increase in PLD activity (EC50 = 0.3 mol%), suggesting a regulatory role of this phospholipid in PLD action. The enzyme was inhibited by sodium oleate when partly or fully substituting for octylglucoside in the substrate mixture. The PLD activity was enriched 15-fold by solubilization and purification on a DEAE-Sepharose column. N-Ethylmaleimide (10 mM) markedly inhibited the purified enzyme, indicating the presence of free thiol groups on PLD. Sphingosine (20 microM) and (+/-) propranolol (53 microM) had no direct effect on PLD activity. The present results form the basis for further purification of a PLD from human tissue.

Assessment of the influence of thyroglobulin (Tg) autoantibodies and other interfering factors on the use of serum Tg as tumor marker in differentiated thyroid carcinoma

The purpose of the study was to examine the value of a commercial immunoradiometric (IRMA) method for measuring serum thyroglobulin as a tumor marker after treatment for differentiated thyroid carcinoma. A prospective analysis of consecutive serum samples from 53 patients was performed using the IRMA method and a traditional double antibody radioimmunoassay (RIA). The results were compared with those of 100 healthy control subjects and furthermore the method was validated by investigating sera from 24 patients with Hashimoto's thyroiditis positive for thyroglobulin autoantibodies. Finally, in vitro studies of the influence of thyroglobulin autoantibodies on the method were done. The IRMA method had an acceptable analytical precision and was more sensitive than the RIA. It was furthermore less sensitive to the presence of thyroglobulin autoantibodies but it was affected by them, and it showed less unspecific serum effect. Both methods had limitations as tumor marker when the patients had a thyroid remnant, when serum thyrotropin was not suppressed, and in cases of local recurrence. The highest predictive value was found in patients with distant metastases. Thus, in cases of only slightly elevated serum thyroglobulin, the strongest indication for recurrence is still an increasing serum thyroglobulin level within the same patient rather than a single value.

[Bilateral anterior shoulder luxation--an overlooked case]

A case of missed first time bilateral anterior dislocation of the shoulders caused by a grand mal seizure is presented. The lack of asymmetry of the shoulders is stressed as a potential pitfall in the clinical evaluation of patients with this condition.

[Cancer in the middle ear and the auditory canal]

Thirty-seven patients with malignant tumours in the ear treated at Rigshospitalet, Copenhagen in the period 1.6.1983-1.6.1993 were retrospectively reviewed. There were 20 males and 17 females. The average age was 67 years. Twenty-four patients had tumours involving the middle ear and 13 patients had tumours located only in the external auditory canal. Eighty-four percent had squamous cell carcinoma. In 61% of the patients with squamous cell carcinoma, chronic infection of the ear preceded the malignant process. Overall control of disease for the 37 patients was 49%. The total actuarial crude survival was 33%. For the nine patients who had squamous cell carcinoma located only in the external auditory canal, the control of disease was 89%. Twenty-two patients had squamous cell carcinoma involving the middle ear. Most of these patients underwent radical mastoidectomy and step-wise removal of gross tumour followed by radiotherapy. Six had radiotherapy alone. The control of disease in this group was 32%. It is concluded that tumours involving only the external auditory canal have a good prognosis. If the tumour involves the middle ear, the prognosis falls dramatically.

Erythrocyte levels compared with reported dietary intake of marine n-3 fatty acids in pregnant women

It is well established that marine n-3 fatty acids measured in erythrocyte phospholipids of non-pregnant subjects reflect the subjects' intake of these fatty acids. In 135 pregnant women in the 30th week of gestation we compared intake of marine n-3 fatty acids and energy, estimated by a combined dietary self-administered questionnaire and interview, with fatty acids measured in erythrocyte phospholipids. Daily intake (g/d) and nutrient density of marine n-3 fatty acids (mg/MJ) correlated with the n-3 fatty acid: arachidonic acid ratio (FA-ratio) with correlation coefficients of 0.48 and 0.54 respectively. In a linear regression model with three frequency questions about marine sandwiches, marine cooked meals and fish oil as explanatory variables, and the FA-ratio as dependent variable, the multiple correlation coefficient was 0.46. Conclusions from the study were (1) levels of erythrocyte fatty acids in pregnant women may be employed as a qualitative method to rank subjects according to intake of marine n-3 fatty acids; (2) with respect to the power to explain FA-ratio variability, three simple marine food frequency questions were comparable with intake of marine n-3 fatty acids assessed by an elaborate semiquantitative dietary method involving an interview.

Gestation length and birth weight in relation to intake of marine n-3 fatty acids

It has been hypothesized that marine n-3 fatty acids ingested during pregnancy prolong duration of pregnancy and increase fetal growth rate in humans. By a combined self-administered questionnaire and interview applied in the 30th week of gestation we assessed dietary intake of marine n-3 fatty acids and energy in a population-based sample of 965 pregnant Danish women; in a random 14% subsample we also measured marine n-3 fatty acids relative to arachidonic acid (FA-ratio) in erythrocytes. Mean intake of marine n-3 fatty acids was 0.25 (95% range 0-0.75) g/d. We could detect no association between n-3 fatty acid intake and FA-ratio on the one hand, and gestation length, birth weight and birth length on the other. The analyses were adjusted for maternal height, prepregnant weight, parity and smoking. The conclusion from the study was that within the intake range of this population, marine n-3 fatty acids ingested in the weeks prior to the 30th week of pregnancy seem not to be a predictor of gestation length or fetal growth rate.

The impact of lymph node metastases on the results of treatment by primary radiotherapy and secondary surgery in oropharyngeal cancer

The prognostic significance of lymph node metastases was evaluated in an unselected material of 427 oropharyngeal cancer patients treated primarily with radiotherapy. At first referral, palpable lymph node metastases were present in 60% of the patients. After irradiation, 60% of all palpable nodes had disappeared. As many as 50% of the nodes initially palpable in N3 patients vanished after irradiation. Recurrences were significantly increased in patients primarily with lymph node metastases (N1-3) compared with N0 patients; recurrences in the primary tumour site were (56% vs. 43%) in neck lymph nodes (40% vs. 9%) and in distant metastases (14% vs. 5%). Surgery was performed in 98 of 256 patients (38%) with recurrent or metastatic disease. The 5-year disease-free survival rate after radiotherapy for N0 patients was an improvement (44%) on that of N1-3 patients (23%). The N-stage is an important prognostic factor for oropharyngeal cancer patients.

Agents that increase phosphatidic acid inhibit the LH-induced testosterone production

The results of the present study point to phosphatidic acid (PtdOH) as a possible intracellular messenger, which might be involved in local modulation of testicular testosterone production in vivo. Propranolol (27-266 microM) induced an increased level of [3H]PtdOH in isolated rat Leydig cells, prelabeled with [3H]myristate, and at the same time a strong dose-dependent inhibition of the acute testosterone production stimulated by luteinizing hormone (LH). The inhibition was not bypassed by the addition of dibutyryl-cAMP but was overcome, when 22(R)-hydroxycholesterol was added as a direct substrate for cytochrome P-450 side chain cleavage enzyme. Thus, the inhibition appears to be exerted at a point distal to cAMP-generation but before the first enzyme in the testosterone synthetic pathway. Treatment with other agents (4 beta-phorbol 12-myristate 13-acetate (PMA), A23187, and sphingosine) giving rise to increases in the PtdOH-level resulted in the inhibition of the LH-induced testosterone formation as well, thus indicating a connection between the two effects. Furthermore, we were able to demonstrate a highly significant correlation between the PtdOH-increase and the inhibition of the LH-stimulated testosterone production. This may suggest a causal relationship between these two parameters.

[Anesthesiological aspects of laparoscopy in gynecological surgery]

A review of anaesthesia for gynaecologic laparoscopic surgery is given. Special criteria are needed for selection of patients, choice of anaesthesia and intraoperative monitoring. The cardiovascular and respiratory system are affected by tension from the pneumoperitoneum, absorption of CO2 and Trendelenburg position. Gas insufflation can provoke venous gas embolism, pneumothorax, pneumomediastinum, pneumopericardium and subcutaneous emphysema. The introduction of laparoscopic instruments may result in unintentional injuries to intra-abdominal organs. The possibility that the procedure may have to be converted to open laparotomy needs to be considered. Bowel burns may result in perforation, peritonitis and sepsis. Laparoscopy is contraindicated in patients with serious cardiac disease, extensive bowel adhesions or intestinal obstruction. General anaesthesia with muscle paralysis, tracheal intubation and controlled ventilation is the preferred technique in these cases. Short acting anaesthetics are preferred in day case laparoscopy. Central neural blockade or infiltration anaesthesia supplemented with sedation and analgetics can be used for short laparoscopic procedures. The electrocardiogram, noninvasive arterial pressure monitor, airway pressure monitor, intra-abdominal pressure monitor, pulse oximeter and CO2 monitor are used routinely. Antiemetics and analgetics may be needed postoperatively.

[Medullary thyroid cancer--screening]

It is possible to screen for medullary thyroid cancer (MTC) with biochemical tests, imaging and genetic testing in families with multiple endocrine neoplasia type 2. The recommendation is based on a consensus statement made by the Members of the European Community concerted action for MTC. The prognostic characteristics are based on 117 patients with MTC diagnosed in Denmark between 1970-1991. Twenty percent of all MTC patients were members of families with two or more thyroid cancer patients. More than half of all MTC patients had neck lymph node involvement at the time of diagnosis. The frequency of neck lymph node involvement was however only 20% amongst those with familiar MTC.

New biological and clinical roles for the n-6 and n-3 fatty acids

Four new findings of the biochemistry and biology of the essential n-6 and n-3 fatty acids have recently been demonstrated. These findings will augment current knowledge as to the role of the essential fatty acids in human health.

Cytoprotective effect of tocopherols in hepatocytes cultured with polyunsaturated fatty acids

When highly unsaturated fatty acids are added to cell cultures, it can become important to include antioxidants in the culture medium to prevent cytotoxic peroxidation. To find an optimal antioxidant for this purpose, the effect of 50 microM alpha-tocopherol, gamma-tocopherol, alpha-tocopheryl acetate, alpha-tocopheryl acid succinate, or alpha-tocopheryl phosphate, or of 1 microM N,N'-diphenyl-1,4-phenylenediamine, was investigated with respect to the agent's ability to prevent lactate dehydrogenase leakage in long-term rat hepatocyte cultures supplemented with 0.5 mM highly unsaturated fatty acids. Formation of thiobarbituric acid reactive substances in the cultures was also measured. alpha-Tocopheryl acid succinate was found to be the most effective cytoprotective compound, followed by N,N'-diphenyl-1,4-phenylenediamine, alpha-tocopherol, gamma-tocopherol and alpha-tocopheryl acetate, and alpha-tocopheryl phosphate was without effect.

Evaluation of peak expiratory flow variability in an adolescent population sample. The Odense Schoolchild Study

The validity of peak expiratory flow (PEF) recordings and the sensitivity of PEF variability indices in asthma and asthma-like conditions were examined in an adolescent population. Recordings from 245 randomly selected subjects and from an additional 181 subjects reporting or considered at risk for developing asthma were analyzed. Subjects recorded PEF twice daily for 2 wk using Mini-Wright meters, completed a symptoms questionnaire, and were tested for airway responsiveness to methacholine. The first three recording days showed significant accumulation of lowest PEF values recorded (41%) and were excluded from further analysis. Among nine PEF variability indices, the Two-lowest%mean (the mean of the two lowest PEF values as a percentage of the period mean) had the best sensitivity for physician-diagnosed asthma (28%). The sensitivity of the methacholine dose-response slope (DRS) was 69%. Combining these indices, a sensitivity of 77% for diagnosed asthma was obtained. Among subjects with asthma-like symptoms but no diagnosis of asthma, 14% had increased Two-lowest%mean and the DRS was increased in 17%, but only 3% were identified by both tests. In conclusion, inhomogeneity of PEF data could be corrected by disregarding the first three recording days. PEF variability indices identified some diagnosed asthmatics, and particularly some symptomatic "nonasthmatics," not identified by the DRS, suggesting that the combined use of these indices might be helpful.

[Fish oil supplementation and duration of pregnancy. A randomized controlled trial]

It was hypothesised from previous observational studies in the Faroes and Denmark that dietary marine n-3 fatty acids would prolong the duration of pregnancy and thereby increase the birth weight, by influencing the production of prostaglandins involved in the process of parturition. Five hundred and thirty-three healthy Danish women were randomly assigned in the 30th week of pregnancy to fish oil (2.7 g n-3 fatty acids (4 1-g capsules Pikasol oil) per day), olive oil (4 1-g capsules per day) or no oil supplementation. The three groups differed in mean gestational age at birth (ANOVA, p = 0.006), with the fish oil group ranking highest and the olive oil group lowest. Babies born to women allocated fish oil had on average 4.0 (95% confidence interval 1.5;6.4) days higher gestational age and 107 (95% confidence interval 1;214) g higher weight at birth than babies born to women allocated olive oil; the difference in gestational age depended on the level of fish intake at enrollment, with a low fish intake enhancing the difference. Fish oil supplementation in the third trimester seems to prolong gestation while allowing continued growth of the foetus; this effect seems to explain the difference between the Faroes and Denmark in pregnancy duration.

Familial clusters of nasopharyngeal carcinoma and salivary gland carcinomas in Greenland natives

BACKGROUND

Nasopharyngeal carcinoma (NPC) and anaplastic salivary gland carcinoma (SGC), both associated with Epstein-Barr virus (EBV), are common among Inuit from Greenland, Canada, and Alaska. Because immigrant studies have shown that factors acting early in life are important for the development of NPC, the authors interviewed new patients in Greenland with either NPC or SGC about their lifestyles during childhood and additional cases in their families.

METHODS

On admission, new patients from Greenland with either NPC or SGC were interviewed about childhood life-style, family size, and other cases of NPC or SGC within the family. Additional cases were confirmed by review of the medical records concerning these patients.

RESULTS

During the 11 years from 1980 through 1990, 17 of 63 (27%) cases in Greenland were found in familial clusters among first-degree relatives. There were no differences in the life-styles of multiple-case families and single-case families.

CONCLUSIONS

The high rate of familial clusters among natives of Greenland is of interest because EBV is believed to play a role in the origin of these two diseases similar to that of Marek disease in neurolymphomatosis of chickens. Therefore, the familial clustering of NPC and SGC may indicate that an enhanced oncogenic potential of an EBV strain may occur more frequently in Greenland than in other parts of the world.