Eleven novel APC mutations identified in Portuguese FAP families

Germline mutations of the adenomatous polyposis coli (APC) gene are responsible for familial adenomatous polyposis (FAP), an autosomal dominant predisposition to colorectal cancer. In the present study we screened all of the exons of the APC gene in individuals belonging to 85 Portuguese FAP families. We here report eleven novel mutations which are predominantly frameshifts or single base substitutions, resulting in premature stop codons. Hum Mutat 16:178, 2000.

Congenital cystic disease of the liver and kidney in a pygmy goat

A 1-month-old pygmy goat was presented with abdominal distension and hematuria. Anemia, leukocytosis, and increased bilirubin and blood urea nitrogen levels suggested renal and hepatic disease. Radiographs revealed bilateral renomegaly, and ultrasound confirmed bilateral hydronephrosis. Necropsy findings determined that the renomegaly was due in part to edema and marked cystic tubular distension. Similarly, intrahepatic bile ducts were ectatic. The character and distribution of the gross and histologic lesions were consistent with a polycystic disorder, presumably congenital, affecting the liver and the kidney.

Effects of salts on Debaryomyces hansenii and Saccharomyces cerevisiae under stress conditions

The effect of Na+ and K+ on growth and thermal death of Debaryomyces hansenii and Saccharomyces cerevisiae were compared under stress conditions as those commonly found in food environments. At the supraoptimal temperature of 34 degrees C both cations at concentrations of 0.5 M stimulated growth of D. hansenii, while K+ had no effect and Na+ inhibited growth of S. cerevisiae. At 8 degrees C, close to the minimum temperature for growth in both species, both cations inhibited both yeasts, this effect being more pronounced with Na+ in S. cerevisiae. At extreme pH values (7.8 and 3.5) both cations at concentrations of 0.25 M stimulated D. hansenii while Na+ inhibited S. cerevisiae. K+ inhibited this yeast at pH 3.5. Thermal inactivation rates, measured at 38 degrees C in D. hansenii and at 48 degrees C in S. cerevisiae, decreased in the presence of both cations. This protective effect could be observed in a wider range of concentrations in D. hansenii. These results call the attention to the fact that not all yeasts have the same behaviour on what concerns synergy or antagonism of salt together with other stress factors and should be taken into consideration in the establishment of food preservation procedures.

Liver iron excess in patients with hepatocellular carcinoma developed on viral C cirrhosis

BACKGROUND

Liver iron deposits are frequent in viral C cirrhotic patients but their role is not well defined.

AIMS

To investigate the effect of liver iron excess on the prevalence of hepatocellular carcinoma (HCC) in patients with viral C cirrhosis.

METHODS

Hepatic iron was evaluated retrospectively using a semiquantitative method in liver biopsies of 104 viral C cirrhotic patients, 48 with HCC and 56 controls (HCC free). Corrected total iron score (0-60) was defined by the sum of three scores: hepatocytic iron score (0-36), sinusoidal iron score (0-12), and portal iron score (0-12), multiplied by 3/3, 2/3, or 1/3 according to the heterogeneous iron localisation in the nodules.

RESULTS

After adjustment for known risk factors for HCC, regression analysis showed that iron deposits (corrected total iron score >0) were more frequent in HCC patients than in controls (odds ratio 4.94; 95% confidence interval 1.59-15. 32; p=0.0056). The median of corrected total iron score was significantly higher in HCC patients than in controls (odds ratio 1. 092; 95% confidence interval 1.01-1.13; p=0.021). This liver iron overload was sinusoidal (odds ratio 5.2; 95% confidence interval 1. 82-15.11; p=0.0022).

CONCLUSIONS

Liver iron deposition was more frequent and more important in viral C cirrhotic patients with HCC than in HCC free controls. Liver iron overload seems to contribute to the development of HCC in patients with viral C cirrhosis.

Hartshill rectangle: failure of spinal stabilisation in acute spinal cord injury

A high rate of failure of the internal fixation of unstable spinal fractures in complete cord injured patients was noted in patients referred to the Salisbury Spinal Centre who had been stabilised with a Hartshill rectangle. This prompted a review of the operative notes, radiographs and clinical outcomes of all patients referred to the centre with a Hartshill rectangle in situ. All patients identified with a complete spinal cord injury and Hartshill rectangle were identified. Forty-three such patients referred from 13 different centres were found. Pre- and postoperative radiographs were assessed for fracture pattern and for spinal correction. Operative outcome in terms of pain and complications relating to surgery were identified. The most recent radiographs were assessed for signs of loss of reduction or stabilisation. Follow-up averaged 84 months (range 36-132 months). Of the 43 identified patients, 19 were found to have unsatisfactory stabilisation. Persistent pain, broken implants and worsening kyphosis were the main complications. The failure to use bone graft at the time of stabilisation was significantly (P < 0.001) related to risk of failure. The application and use of the Hartshill is not a technically challenging procedure; however, if the system is to be used, it must be used correctly. Failure to correctly apply the rectangle and to use bone graft will lead to an unacceptably high rate of failure.

Degradation of Aux/IAA proteins is essential for normal auxin signalling

The growth substance auxin mediates many cellular processes, including division, elongation and differentiation. PSIAA6 is a member of the Aux/IAA family of short-lived putative transcriptional regulators that share four conserved domains and whose mRNAs are rapidly induced in the presence of auxin. Here PSIAA6 was shown to serve as a dominant transferable degradation signal when present as a translational fusion with firefly luciferase (LUC), with an in vivo half-life of 13.5 min in transgenic Arabidopsis seedlings. In a transient assay system in tobacco protoplasts using steady-state differences as an indirect measure of protein half-life, LUC fusions with full-length PSIAA6 and IAA1, an Aux/IAA protein from Arabidopsis, resulted in protein accumulations that were 3.5 and 1. 0%, respectively, of that with LUC alone. An N-terminal region spanning conserved domain II of PSIAA6 containing amino acids 18-73 was shown to contain the necessary cis-acting element to confer low protein accumulation onto LUC, while a fusion protein with PSIAA6 amino acids 71-179 had only a slight effect. Single amino acid substitutions of PSIAA6 in conserved domain II, equivalent to those found in two alleles of axr3, a gene that encodes Aux/IAA protein IAA17, resulted in a greater than 50-fold increase in protein accumulation. Thus, the same mutations resulting in an altered auxin response phenotype increase Aux/IAA protein accumulation, providing a direct link between these two processes. In support of this model, transgenic plants engineered to over-express IAA17 have an axr3-like phenotype. Together, these data suggest that rapid degradation of Aux/IAA proteins is necessary for a normal auxin response.

Sensitization to individual allergens as risk factors for lower FEV1 in young adults. European Community Respiratory Health Survey

BACKGROUND

Atopy may impair ventilatory function, but results are controversial. We assess the association between individual reactivity to allergens and the level of baseline maximal one-second forced expiratory volume (FEV1), by smoking and respiratory symptoms.

METHODS

The 1472 participants (response 44.5%) of the five Spanish areas of the European Community Respiratory Health Survey (ECRHS) who performed respiratory function tests, skin prick tests and/or specific IgE against common aeroallergens (e.g. mites, pets, mould, pollens) are included. Bronchial hyperreactivity (BHR) was measured with a methacholine challenge.

RESULTS

After adjusting for BHR and smoking, in addition to the other allergens, skin reactivity to Alternaria (-208 ml; 95% CI :-451, 35) and IgE antibodies against cat (-124 ml; 95% CI:-269, 21) and Timothy grass (-115 ml, 95% CI:-190, -40) were associated with a decrease in FEV1 in females. Among males, skin reactivity to olive showed the strongest association (-111 ml; 95% CI: -261, 38). The associations were stronger in females. Smoking modifies the association for Alternaria and cat (P for interaction < 0.05). While cat is associated with a decrease in FEV1 in current smokers (-190 ml), Alternaria (-336 ml) was associated among never smokers. The exclusion of subjects with asthma symptoms, or adjustment for respiratory symptoms, led to similar results.

CONCLUSIONS

We conclude that immunoresponse to individual allergens (particularly outdoor) is associated with the level of FEV1, and this association occurred independently of asthma, and in smokers and non-smokers, which may be of interest in natural history of chronic obstructive pulmonary disease (COPD).

Trk1 and Trk2 define the major K(+) transport system in fission yeast

The trk1(+) gene has been proposed as a component of the K(+) influx system in the fission yeast Schizosaccharomyces pombe. Previous work from our laboratories revealed that trk1 mutants do not show significantly altered content or influx of K(+), although they are more sensitive to Na(+). Genome database searches revealed that S. pombe encodes a putative gene (designated here trk2(+)) that shows significant identity to trk1(+). We have analyzed the characteristics of potassium influx in S. pombe by using trk1 trk2 mutants. Unlike budding yeast, fission yeast displays a biphasic transport kinetics. trk2 mutants do not show altered K(+) transport and exhibit only a slightly reduced Na(+) tolerance. However, trk1 trk2 double mutants fail to grow at low K(+) concentrations and show a dramatic decrease in Rb(+) influx, as a result of loss of the high-affinity transport component. Furthermore, trk1 trk2 cells are very sensitive to Na(+), as would be expected for a strain showing defective potassium transport. When trk1 trk2 cells are maintained in K(+)-free medium, the potassium content remains higher than that of the wild type or trk single mutants. In addition, the trk1 trk2 strain displays increased sensitivity to hygromycin B. These results are consistent with a hyperpolarized state of the plasma membrane. An additional phenotype of cells lacking both Trk components is a failure to grow at acidic pH. In conclusion, the Trk1 and Trk2 proteins define the major K(+) transport system in fission yeast, and in contrast to what is known for budding yeast, the presence of any of these two proteins is sufficient to allow growth at normal potassium levels.

[Validation of the Spanish version of PRIME-MD: a procedure for diagnosing mental disorders in primary care]

INTRODUCTION

Psychiatric disorders occurs in at least 20% of patients attending Primary Care settings, however, only 50% of them are detected by primary care physicians. Therefore a tool is required which can help primary care physicians to detect and diagnose psychiatric disorders. PRIME-MD (Primary Care Evaluation of Mental Disorders) is a questionnaire designed with this aim. In this article the results of the validation study of the Spanish version of this questionnaire are presented.

MATERIALS AND METHODS

312 patients were interviewed by primary care physicians using PRIME-MD and by psychiatrists using SCAN (Schedules for Clinical Assessment in Neuropsychiatry).

RESULTS

The time most frequently spent in questionnaire application by the physician was 10 minutes. PRIME-MD detected the presence of at least one psychiatric disorder in 44.3% of patients. PRIME-MD diagnoses agree well with SCAN diagnoses for mood disorders (coefficient of agreement: 0.50) and for anxiety disorders (coefficient of agreement: 0.35), but not for somatoform disorders or alcohol-related disorders.

CONCLUSIONS

The Spanish version of PRIME-MD questionnaire in a useful tool to identify and diagnose mood and anxiety disorders in Primary Care settings.

Biochemical and genetic analyses of the role of yeast casein kinase 2 in salt tolerance

Saccharomyces cerevisiae cells lacking the regulatory subunit of casein kinase 2 (CK-2), encoded by the gene CKB1, display a phenotype of hypersensitivity to Na(+) and Li(+) cations. The sensitivity of a strain lacking ckb1 is higher than that of a calcineurin mutant and similar to that of a strain lacking HAL3, the regulatory subunit of the Ppz1 protein phosphatase. Genetic analysis indicated that Ckb1 participates in regulatory pathways different from that of Ppz1 or calcineurin. Deletion of CKB1 increased the salt sensitivity of a strain lacking Ena1 ATPase, the major determinant for sodium efflux, suggesting that the function of the kinase is not mediated by Ena1. Consistently, ckb1 mutants did not show an altered cation efflux. The function of Ckb1 was independent of the TRK system, which is responsible for discrimination of potassium and sodium entry, and in the absence of the kinase regulatory subunit, the influx of sodium was essentially normal. Therefore, the salt sensitivity of a ckb1 mutant cannot be attributed to defects in the fluxes of sodium. In fact, in these cells, both the intracellular content and the cytoplasm/vacuole ratio for sodium were similar to those features of wild-type cells. The possible causes for the salt sensitivity phenotype of casein kinase mutants are discussed in the light of these findings.

Pulp and paper from blue agave waste from tequila production

Pulping of blue agave waste, from the production of tequila, was evaluated by both chemical and biomechanical pulping processes. Two conventional and two organosolv systems were used to pulp the agave waste under a standard set of conditions. The soda-ethanol process was superior in terms of delignification and pulp properties in comparison to the soda and ethanol organosolv processes for pulping of agave waste; however, the kraft process gave the best strength properties. In general, the strength of the agave waste pulps was rather poor in comparison to wood and other agro-based pulps; however, the tear strength was relatively high. This result is typical of poorly bonded sheets and may be due to the coarseness of the agave fibers and/or loss of hemicelluloses in the steaming process for the tequila production. Fungal treatment of the agave waste with Ceriporiopsis subvermispora reduced the energy consumption for mechanical refining but gave biomechanical pulps with inferior strength properties. The blue agave chemical pulps should be suitable for blending with softwood kraft pulps for publication grade paper.

[Non-invasive mechanical ventilation in patients with severe stable COPD]

BACKGROUND

The benefits of non-invasive mechanical ventilation (NIMV) in hypercapnic patients with severe stable COPD remain controversial mainly due to their unknown mechanisms.

AIM

To assess the clinical and physiological benefits of a 3 weeks period of intermittent NIMV and their underlying mechanisms in COPD patients.

PATIENTS AND METHODS

Twelve patients (10 male) prospectively recruited (age 65 +/- 3 years, FEV1 27 +/- 2% predicted, PaO2 46 +/- 2 mmHg, PaCO2 55 +/- 2 mmHg) were submitted to NIMV using a commercially available system (BiPAP) 3 h a day, 5 days a week for 3 weeks. Arterial blood gases, 6 min walking distance, dyspnea (Mahler's scale), breathing pattern, PIMax, ventilatory drive (P0.1) and the impedance of the respiratory system (P0.1/V1/T1) were measured before and after NIMV.

RESULTS

A significant improvement in PaO2, PaCO2, PIMax, dyspnea and exercise capacity was observed in addition to a trend for VT to increase and for respiratory rate (RR) to decrease. The impedance of the respiratory system showed a significant reduction. Ventilatory drive, normalized for PaCO2 levels, did not change. Improvement in PaCO2 was related to an increase in Vp whereas a significant association between the reduction in RR and the fall in respiratory system impedance was also found.

CONCLUSIONS

Our study supports previous data demonstrating that NIMV improves clinical and physiologic parameters in advanced stable COPD and suggest that the underlying mechanism is a reduction in the inspiratory load. A randomized clinical trial is needed to confirm that this mechanism is operative.

[European Asthma Study. Identifying and treating young adults with epidemiological criteria for asthma in five areas of Spain. Spanish Group of the European Asthma Study]

BACKGROUND AND OBJECTIVES

Asthma's great impact on public health stems from its chronicity and to high prevalence among all age groups and both sexes. To estimate the appropriateness of treatment and management of asthma in Spain during the period of 1991 and 1992, we analyzed data from the European Community Respiratory Health Survey (ECRHS).

METHOD

The ECRHS was undertaken with a random sample of 20-to-44-year-olds in Albacete, Barcelona, Galdakao, Huelva and Oviedo. In total, 181 individuals with asthma were identified. Current asthma was defined as the presence of respiratory symptoms associated with asthma within the past 12 months and a positive methacholine challenge test.

RESULTS

Subjects who were unaware of having asthma made up 57.5% (CI: 49.9-64.8%), and 35.9% (CI: 27.9-42.3%) were not following any specific treatment. Among asthmatics who reported having continuous or frequent respiratory symptoms, 25.9% (CI: 15.3-39.0%) were not following any treatment.

CONCLUSION

Over half the individuals with asthma in 1991 to 1993 were unaware of having the disease at the time of the study or of ever having had it, and approximately one third were not in treatment. The delivery of appropriate treatment in asthma generally, and in asthma with continuous or frequent respiratory symptoms, was markedly inadequate during the period studied.

High-grade carcinoma component in epithelial-myoepithelial carcinoma of salivary glands clinicopathological, immunohistochemical and flow-cytometric study of three cases

Three cases of epithelial-myoepithelial carcinoma (EMC) with coexisting areas of high grade carcinoma are reported. In two of the cases there was a previous recurrence, and in all three patients there had been a sudden increase in size before final surgery. The typical ductal and myoepithelial components of EMC showed the usual biphasic pattern and the expected immunophenotypes, with expression of wide spectrum cytokeratins, Cam 5.2 and EMA in the ductal part, and muscle-specific actin, smooth muscle actin, S-100 protein, vimentin and cytokeratins in the myoepithelial component. These areas also had a low mitotic count and low proliferation rate as measured by immunohistochemistry and by flow cytometry. Conversely, areas of high-grade tumour had the features of a large cell carcinoma, with focal mucin secretion in two cases. This high-grade component showed an epithelial immunophenotype in two cases, and was negative for all tested markers in the third one. The mitotic counts and the proliferation rates were much higher in these anaplastic areas. One of the patients died 3 months after treatment; another developed lymph node metastases 1 year later and was alive after 6 years of follow-up. The third patient was alive without evidence of disease 7 months after wide surgical resection of the tumour. The possibility of anaplastic transformation in EMC makes thorough sampling mandatory in this type of neoplasm.

Acute hepatitis after riluzole administration

Riluzole is a new drug representing the first active treatment for amyotrophic lateral sclerosis. We report the cases of two patients who developed acute hepatitis after taking riluzole at the recommended dose (100 mg daily) for 7 and 4 weeks, respectively. In both cases, liver histology showed hepatocellular damage with inflammatory infiltration and microvesicular steatosis without fibrosis. Liver enzymes returned to normal 4 and 8 weeks, respectively, after riluzole withdrawal. In one case, the readministration of riluzole was followed by the relapse of hepatitis. These two observations strongly suggest that riluzole can induce acute hepatitis with associated hepatocellular damage and microvesicular steatosis. They also suggest that liver enzymes should be monitored during treatment with riluzole.

The Schizosaccharomyces pombe Pzh1 protein phosphatase regulates Na+ ion influx in a Trk1-independent fashion

We have previously shown that fission yeast encodes a PPZ-like phosphatase, designated Pzhl, which is an important determinant of cation homeostasis. pzh1 delta mutants display increased tolerance to Na+ ions, but they are hypersensitive to KC1 [Balcells, L., Gómez, N., Casamayor, A., Clotet, J. & Ariño, J. (1997) Eur. J. Biochem. 250, 476-483]. We have immunodetected Pzh1 in yeast extracts and found that this phosphatase is largely associated with particulate fractions. Cells defective in Pzh1 do not show altered efflux of Na+ or Li+ ions, but they accumulate these cations more slowly than wild-type cells. K+ ion content of pzh1 delta cells is about twice that of wild-type cells, and this can be explained by decreased efflux of K+. Therefore, Pzh1 may regulate both Na+ influx and K+ efflux in fission yeast. To test the possible relationship between K+ uptake, Na+ tolerance and Pzh1 function, we deleted the trk1+ gene, which encodes a putative high-affinity transporter of K+ ions. trkl delta mutants grew well even at relatively low concentrations of KCl and did not show significantly altered content or influx of K+ ions. However, they showed a Na(+)-sensitive phenotype which was greatly intensified by deletion of the sod2+ gene (which encodes the major determinant for efflux of Na+ ions), and clearly ameliorated by deletion of the pzh1 phosphatase, as well as by moderate concentrations of KCl in the medium. These results suggest that Trk1 does not mediate the effect of Pzh1 on NaCl tolerance and that fission yeast contains efficient systems, other than Trk1, for uptake of K+ ions.

Fps1p controls the accumulation and release of the compatible solute glycerol in yeast osmoregulation

The accumulation of compatible solutes, such as glycerol, in the yeast Saccharomyces cerevisiae, is a ubiquitous mechanism in cellular osmoregulation. Here, we demonstrate that yeast cells control glycerol accumulation in part via a regulated, Fps1p-mediated export of glycerol. Fps1p is a member of the MIP family of channel proteins most closely related to the bacterial glycerol facilitators. The protein is localized in the plasma membrane. The physiological role of Fps1p appears to be glycerol export rather than uptake. Fps1 delta mutants are sensitive to hypo-osmotic shock, demonstrating that osmolyte export is required for recovery from a sudden drop in external osmolarity. In wild-type cells, the glycerol transport rate is decreased by hyperosmotic shock and increased by hypo-osmotic shock on a subminute time scale. This regulation seems to be independent of the known yeast osmosensing HOG and PKC signalling pathways. Mutants lacking the unique hydrophilic N-terminal domain of Fps1p, or certain parts thereof, fail to reduce the glycerol transport rate after a hyperosmotic shock. Yeast cells carrying these constructs constitutively release glycerol and show a dominant hyperosmosensitivity, but compensate for glycerol loss after prolonged incubation by glycerol overproduction. Fps1p may be an example of a more widespread class of regulators of osmoadaptation, which control the cellular content and release of compatible solutes.

Management of intraductal papillary mucinous tumours of the pancreas

OBJECTIVE

To focus attention on the management and outcome of patients with intraductal papillary mucinous tumours of the pancreas.

DESIGN

Retrospective study and analysis of published reports.

SETTING

University hospital, France.

SUBJECTS

111 patients (101 published cases and our own 10 cases) divided in two groups: the first including malignant tumours (n = 46), and the second group benign or in situ tumours (n = 61). In 4 patients the type of tumour was not known.

MAIN OUTCOME MEASURE

Resectability, mortality and recurrence.

RESULTS

More men had benign or in situ tumours [48/61 (79%) compared with 28/46 (61%), p = 0.054]. Pancreatitis was more common among benign than malignant tumours [34/61 (58%) compared with 21/46 (46%), p = 0.33]. In group I, 39 patients had diabetes. A total of 107 patients were operated on: pancreaticoduodenectomy (n = 54, 50%), distal pancreatectomy (n = 25, 23%), total pancreatectomy (n = 4,4%), bypass (n = 2,2%). The type of resection was not mentioned in 22 records (21%). Four patients were not operated on because of their poor general condition. The resectability rate was 98% (105/107). Eleven patients had died at the time of publication. Hospital mortality rate was 3% (n = 3), mainly because 2 of the 4 who had total pancreatectomy died. With a median follow-up of 37 months, recurrence was 5% (n = 5).

CONCLUSION

Intraductal papillary mucinous tumours of the pancreas are well known distinctive pancreatic tumours that are usually intraductal but may develop into invasive carcinoma. They should be resected, and have a good prognosis and low recurrence rate.