A genetic map of potato (Solanum tuberosum) integrating molecular markers, including transposons, and classical markers

A genetic map of potato (Solanum tuberosum L.) integrating molecular markers with morphological and isozyme markers was constructed using a backcross population of 67 diploid potato plants. A general method for map construction is described that differs from previous methods employed in potato and other outbreeding plants. First, separate maps for the female and male parents were constructed. The female map contained 132 markers, whereas the male map contained 138 markers. Second, on the basis of the markers in common the two integrated parental maps were combined into one with the computer programme JoinMap. This combined map consisted of 175 molecular markers, 10 morphological markers and 8 isozyme markers. Ninety-two of the molecular markers were derived from DNA sequences flanking either T-DNA inserts in potato or reintegrated maize transposable elements originating from these T-DNA constructs. Clusters of distorted segregation were found on chromosomes 1,2,8 and 11 for the male parent and chromosome 5 for both parents. The total length of the combined map is 1120 cM.

pBINPLUS: an improved plant transformation vector based on pBIN19

We describe the construction of a new plant transformation vector, pBINPLUS, based on the popular pBIN19 vector. Improvements over pBIN19 include location of the selectable marker gene at the left T-DNA border, a higher copy number in E. coli, and two rare restriction sites around the multiple cloning site for easier cloning and analysis of T-DNA insertions in plant genomes.

A two-element Enhancer-Inhibitor transposon system in Arabidopsis thaliana

The Enhancer-Inhibitor (En-I), also known as Suppressor-mutator (Spm-dSpm), transposable element system of maize was modified and introduced into Arabidopsis by Agrobacterium tumefaciens transformation. A stable En/Spm transposase source under control of the CaMV 35S promoter mediated frequent transposition of I/dSpm elements. Transposition occurred continuously throughout plant development over at least seven consecutive plant generations after transformation. New insertions were found at both linked and unlinked positions relative to a transposon donor site. The independent transposition frequency was defined as a transposition parameter, which quantified the rate of unique insertion events and ranged from 7.8% to 29.2% in different populations. An increase as well as a decrease in I/dSpm element copy number was seen at the individual plant level, but not at the population level after several plant generations. The continuous, frequent transposition observed for this transposon system makes it an attractive tool for use in gene tagging in Arabidopsis.

Thrombotic thrombocytopenic purpura/hemolytic uremic syndrome: a multivariate analysis of factors predicting the response to plasma exchange

The aim of this study was to investigate pretreatment prognostic factors that could be useful in predicting the response to plasma exchange in thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS). Thirty-two patients with TTP/HUS, treated with plasma exchange at our institution from 1980 to 1994, were studied. The main clinical and laboratory data at the beginning of plasma exchanges were analyzed by the Cox stepwise logistic regression, applied to either treatment failure or death. Seventeen (53%) patients attained a complete remission and 22 (69%) survived (five in advanced renal failure and long-term hemodialysis). Longer delay in initiating plasma exchanges, presence of stupor or coma, and higher creatinine levels at the beginning of plasma exchanges were independent predictors of treatment failure. Stupor or coma at the beginning of plasma exchanges was the only predictor of mortality from unremitted TTP/HUS. Hemoglobin levels, platelet count, and LDH activity, traditionally envisaged as markers of disease activity, neither correlated with previous duration of TTP/HUS nor had any prognostic value. Early diagnosis of TTP/HUS and prompt initiation of intensive plasma exchange emerged from this study as the most effective interventions for improving the prognosis of TTP/HUS patients.

Ectopic ACTH syndrome

Ectopic ACTH syndrome represents a cancer-induced amplification of a property [proopiomelanocortin (POMC) peptides production] normally present in the cells from which the cancer originated but with aberrant posttranslational processing of POMC resulting in a greatly elevated secretion of ACTH precursors. The classic ectopic ACTH-producing tumors described in the 1960s were highly malignant but more recently slowly growing tumors such as carcinoids are reported with increasing frequency. Clinical features of patients with ectopic ACTH were analyzed, including biochemical abnormalities, plasma ACTH, cortisol and urinary steroids. Dynamic tests such as high-dose dexamethasone suppression, metyrapone and ovine-CRH (oCRH) stimulation were explored, as well as inferior petrosal sinus ACTH sampling before and after oCRH. Among the tumor markers examined, elevation of ACTH precursors was uniformly present followed by increased output of calcitonin, gut hormones, oncofetal and placental hormones in decreasing order. Since more than 90% of ectopic ACTH tumors are neuroendocrine in nature exhibiting APUD characteristics, their 2 markers, neuron-specific enolase and chromogranins are very useful. The imaging procedures for localization of the tumor ranged from chest X-rays to computed tomography and magnetic resonance of the chest and abdomen. Abdominal ultrasonography was also useful. Finally somatostatin receptor scintigraphy permitted demonstration of unrecognized tumors and/or metastases, even when the tumors were occult. The ACTH content, immunostaining for APUD markers and altered POMC processing were evaluated in ectopic tumors and/or metastases. Occult ectopic ACTH syndrome of more than 4-6 months of symptoms without the emergence of an obvious source was reviewed. Since the tumors are often clinically and biochemically undistinguishable from pituitary-dependent Cushing's disease, inferior petrosal sinus sampling for ACTH after oCRH stimulation established the diagnosis in over 90% of the cases. 60% of the occult tumors were thoracic carcinoids (3/4 bronchial carcinoids), followed by small cell lung cancer and pancreatic neuroendocrine tumors. In 12% the primary etiology was not detected. The rare syndrome of ectopic CRH syndrome (6 published cases) leading to excessive stimulation of the pituitary which became hyperplastic and secreted excessive amounts of ACTH is discussed. Finally, the 12 published cases and 1 unreported patient with ectopic CRH-ACTH tumors were reviewed, the majority being metastatic small cell lung carcinomas, bronchial and thymic carcinoids.

[Growth and development of children with low birth weight at their first birthday]

The aim of this prospective study was to evaluate the effect of low birthweight on growth and development at one year of age, in a cohort of infants born between March 1992 and March 1993 at Hospital de Famalicão. Information was obtained from 199 children, 89 low birthweight cases and 110 born with a normal (> or = 2500 g) weight. The infant mortality rate (56 vs 9 per 1000), the frequency of growth (32% vs 4%, p = 0.0000003) or developmental delay (30% vs 11%, p = 0.002) were significantly higher in low birthweight babies. However, all cases of developmental delay corresponded to minor impairments. At age one, children born with a normal weight presented mean higher values for weight (10.0 +/- 1.1 kg vs 9.2 +/- 1.2 kg; p = 0.000005), length (74.2 +/- 7.1 cm vs 72.9 +/- 3.1 cm, p = 0.0006) and head circumference (46.4 +/- 1.9 cm vs 45.8 +/- 1.6 cm; p = 0.004). Prenatal characteristics such as the planning of the pregnancy, gestational birth weight, diseases during the pregnancy, gestational age or twining, significantly affected development at one year of age, showing that delays can be prevented before a child is born. In addition, post-natal exposures, such as home conditions, energy and nutrient intake, or coping with vaccination schedules and the occurrence of diseases during the neonatal and post-neonatal periods were significantly associated to developmental delay.(ABSTRACT TRUNCATED AT 250 WORDS)

[Functional ability and quality of life in rheumatoid arthritis: use of the Functional Independence Measure and the Reintegration to Normal Living Index]

Functional disability and quality of life were evaluated using the Functional Independence Measure and the Reintegration to Normal Living Index, respectively, in 57 subjects (15 men and 42 women) with a mean disease duration of 15 years. Scores on both these nonspecific scales correlated with those obtained using instruments specifically designed for rheumatoid arthritis (ARA index, Lee index) and with a number of clinical parameters including patient age, disease duration and number of affected joints. Functional ability was correlated with quality of life in this study and in others performed using other evaluation tools. Nonspecific assessment scales are useful for comparing function and quality of life in various diseases.

Neural cell-adhesion molecule (CD 56)-positive, t(8;21) acute myeloid leukemia (AML, M-2) and granulocytic sarcoma

A 49-year-old man with t(8; 21) acute myeloid leukemia relapsed 8 months after successful induction chemotherapy with a paraspinal granulocytic sarcoma. There was no evidence of leukemia in the bone marrow at relapse. At initial presentation, the blasts co-expressed CD 15, CD 33, CD 34, CD 45, CD 19, and CD 56 (a neural cell-adhesion molecule). Expression of certain cell-adhesion molecules on leukemic blasts may determine a tendency to develop extramedullary relapse. The co-expression of CD 56 may have a role in the predisposition of t(8; 21) AML to develop GS.

Long-term survivors in chronic granulocytic leukaemia: a study by the International CGL Prognosis Study Group. Italian Cooperative CML Study Group

The purpose of the present work were to identify the initial characteristics associated with long-term survival in chronic granulocytic leukaemia (CGL) and to analyse the accuracy of prognostic models in identifying long-term survivors. 813 Philadelphia (Ph) chromosome-positive, nonblastic CGL patients from six American and European institutions, the majority treated conventionally, with a minimum follow-up > 10 years, were studied. Stepwise logistic regression was performed to ascertain the association between the initial clinicohaematological variables and survival > or = 8 years, and a prognostic index was derived. The usefulness of both Sokal's and the new prognostic index to identify long-term survivors was assessed by calculating their positive and negative predictive accuracies, sensitivity and specificity. Median survival of the series was 45 months (range 1-255), with 784 patients (96.4%) having died and 109 (13.4%) surviving 8 years or longer. Younger age, smaller spleen, platelets < or = 600 x 10(9)/l, and lower blood blast percentage were associated with survival > or = 8 years; platelets < or = 600 x 10(9)/l and lower blood blast percentage were the predictive factors in patients 50 years old or younger. Two-thirds of long survivors belonged to Sokal's low-risk group, but the positive predictive accuracy and specificity for prolonged survival of Sokal's index were very low. This was also the case for the new predictive index.(ABSTRACT TRUNCATED AT 250 WORDS)

Characterization of a monoclonal IgMK (IgMGAS) anti-Gd cold agglutinin (CA). Its coexistence with a monoclonal IgG3K (IgGGAS) without CA activity that might be clonally related to IgMGAS

A monoclonal IgMK (IgMGAS) cold agglutinin (CA) of the infrequent anti-Gd specificity, found in a patient with Waldenström macroglobulinemia, has been characterized. IgMGAS uses a VH gene homologous (93.7%) to the reported VH251 germ-line, one of the two functional genes of the VH5 family, with differences in both framework regions and complementary determining regions (CDR). The VL gene is homologous to the reported 15AVK1 germ-line gene, recently described in an anti-i CA, with differences mostly clustered in CDR. In the patient's serum, IgMGAS coexisted with a monoclonal IgG3K (IgGGAS) that lacked CA activity but expressed the private idiotopes found on IgMGAS. Both Ig lacked reactivity with antibodies detecting VH1 or VHIII or VKIII subgroup regions or the VH4-21 gene product that is expressed by anti-I/i CAs. The K chains from both Igs showed the same isoelectrical mobility. Moreover, the k chains from both serum Igs showed the same N-terminal amino acid sequence. This sequence was identical to that predicted by the nucleotide sequence of VK1GAS gene segment, including one discrepancy at position 15 (Ile for Val) with respect to the consensus VK1 subgroup regions. Although these data do not exclude a possible independent clonal origin, they are consistent with the notion that IgGGAS might be clonally related to IgMGAS.

Segregation analysis and RFLP mapping of the R1 and R3 alleles conferring race-specific resistance to Phytophthora infestans in progeny of dihaploid potato parents

Phytophthora infestans (Mont.) de Bary is the most important fungal pathogen of the potato (Solanum tuberosum). The introduction of major genes for resistance from the wild species S. demissum into potato cultivars is the earliest example of breeding for resistance using wild germplasm in this crop. Eleven resistance alleles (R genes) are known, differing in the recognition of corresponding avirulence alleles of the fungus. The number of R loci, their positions on the genetic map and the allelic relationships between different R variants are not known, except that the R1 locus has been mapped to potato chromosome V. The objective of this work was the further genetic analysis of different R alleles in potato. Tetraploid potato cultivars carrying R alleles were reduced to the diploid level by inducing haploid parthenogenetic development of 2n female gametes. Of the 157 isolated primary dihaploids, 7 set seeds and carried the resistance alleles R1, R3 and R10 either individually or in combinations. Independent segregation of the dominant R1 and R3 alleles was demonstrated in two F1 populations of crosses among a dihaploid clone carrying R1 plus R3 and susceptible pollinators. Distorted segregation in favour of susceptibility was found for the R3 allele in 15 of 18 F1 populations analysed, whereas the R1 allele segregated with a 1:1 ratio as expected in five F1 populations. The mode of inheritance of the R10 allele could not be deduced as only very few F1 hybrids bearing R10 were obtained. Linkage analysis in two F1 populations between R1, R3 and RFLP markers of known position on the potato RFLP maps confirmed the position of the R1 locus on chromosome V and localized the second locus, R3, to a distal position on chromosome XI.

[Significance of the persistence of ST segment elevation in anterior infarction]

OBJECTIVE

Persistent ST segmentary elevation in anterior myocardial infarction was classically attributed to ventricular aneurysm. This association is now considered controversial. We studied the association between this electrocardiographic finding and the left ventricular wall motion abnormalities and global function.

DESIGN

Retrospective study.

SETTING

Patients admitted to Hospital de Pulido Valente Coronary Care Unit in Lisbon with anterior myocardial infarction who were submitted to angiographic study.

PATIENTS

94 patients were included in the study.

METHODS

The global ejection fraction, the regional wall motion abnormalities, the coronary artery disease extension, the patency and the proximal involvement of the left anterior descending artery were investigated.

RESULTS

56 of the 94 patients (60%) had persistent ST segment elevation and 38 (40%) had isoelectric ST segment. The ejection fraction was markedly depressed in the group with elevated ST segment (36.2 SD 17.6) in contrast with the group with isoelectric ST segment (49.3 SD 14.8) (p < 0.001). The group with persistent ST segment elevation had more advanced degrees of left ventricular asynergy (42/58-75%) than the group with isoelectric ST segment (12/38-32%) (p = 0.02). The other studied angiographic variables did not differ between the two groups.

CONCLUSIONS

The group with persistent ST segment elevation was associated with advanced degrees of left ventricular asynergy and greater left ventricular function depression. The ventricular aneurysm was exclusive of the first group.

Pleural effusion in multiple myeloma

We report the first case of IgA-kappa multiple myeloma presenting as a myelomatous and eosinophilic pleural effusion with increased adenosine deaminase activity. In a review of the literature, 80 percent of myelomatous pleural effusions are due to IgA multiple myeloma.

[A left intraventricular thrombus in an adolescent. Its relationship to the anticardiolipin antibody syndrome]

The authors are going to present the clinical case of a 14-years-old female patient who has got an anticardiolipin antibodies syndrome, a theme to which they add some ideas concerning physiopathology and diagnosis criteria. They'd like to emphasise the echocardiographic observation, which allowed them to find out and follow the evolution of a left sided intraventricular thrombus, the real cause for the systemic thrombosis.

Salmonella typhi meningitis

Whereas typhoid fever is still an endemic disease in some parts of the world, meningeal involvement in this disease is a rare occurrence. We report a case of Salmonella typhi meningitis in a 70-year-old woman. The patient was treated with ampicillin and the only sequela was right-sided deafness.

[Atrial myxoma. Apropos a clinical case]

The authors report a case of a 61-years-old woman with hypertension and palpitations, who was diagnosed as having a left auricular myxoma. This diagnosis was established by echocardiography and confirmed afterwards by an histological survey. On the basis of this case the authors reviewed the subject and discuss the role of echocardiography in the diagnosis and follow-up of this kind of patients.

The kinesin-like protein KLP61F is essential for mitosis in Drosophila

We report here that disruption of a recently discovered kinesin-like protein in Drosophila melanogaster, KLP61F, results in a mitotic mutation lethal to the organism. We show that in the absence of KLP61F function, spindle poles fail to separate, resulting in the formation of monopolar mitotic spindles. The resulting phenotype of metaphase arrest with polyploid cells is reminiscent of that seen in the fungal bimC and cut7 mutations, where it has also been shown that spindle pole bodies are not segregated. KLP61F is specifically expressed in proliferating tissues during embryonic and larval development, consistent with a primary role in cell division. The structural and functional homology of the KLP61F, bimC, cut7, and Eg5 kinesin-like proteins demonstrates the existence of a conserved family of kinesin-like molecules important for spindle pole separation and mitotic spindle dynamics.

Effect of splenectomy on von Willebrand factor multimeric structure in thrombotic thrombocytopenic purpura refractory to plasma exchange

Treatment-related changes in plasma von Willebrand factor (vWf) multimers were studied in two patients with thrombotic thrombocytopenic purpura (TTP) undergoing splenectomy because of refractoriness to plasma exchange. In both cases, a decrease in the largest normal vWf multimers was found at presentation. In one case, splenectomy resulted in a long-term remission and was followed by a normal multimeric pattern. In the other case, splenectomy failed to produce a remission and was followed by the appearance of ultralarge multimers, which disappeared--resulting in a normal pattern--when a sustained remission was achieved after vincristine infusion and further plasma exchanges. These results suggest that splenectomy per se has no consistent effect on the vWf multimeric structure in TTP patients, and provide further evidence on the good prognostic value of the achievement of a normal multimeric pattern in these patients.

Significant correlation between 14C-5-HT uptake by and 3H-paroxetine binding to platelets from healthy volunteers

The lack of correlation between 5-HT uptake by platelets and the ability of platelet membrane to bind antidepressant drugs, particularly imipramine, has been reported. However, more recently it has been suggested that 3H-paroxetine could be a better drug with which to study the platelet 5-HT uptake mechanism in disease states. We have therefore compared the ability of platelet-rich plasma (PRP) from normal individuals to take up 5-HT with the ability of platelet membranes to bind paroxetine. A significant correlation was apparent between the Vmax of 14C-5-HT uptake by PRP and the Bmax of 3H-paroxetine binding to platelet membrane from 30 individuals (r = 0.6468, p = 0.0001). Furthermore, this correlation was highly significant in the 20 female (r = 0.7768, p = 0.00006) but not in the 10 male volunteers. There was also a significant association between Vmax and Bmax and the month of blood sampling but this did not totally account for the correlation between Vmax and Bmax. The simultaneous measurement of 5-HT uptake by PRP and paroxetine binding to platelet membranes from both depressed patients and matched controls should be carried out to confirm and extend these findings.

[Initial iron deposits in idiopathic myelofibrosis. Analysis of 20 patients]

PURPOSE

To analyse the status of iron deposits at diagnosis in patients with idiopathic myelofibrosis (IM).

PATIENTS AND METHODS

The study included twenty consecutive patients with IM. Haemoglobin, MCV, serum iron and serum ferritin were determined in each case. Perls stain was used to evaluate iron deposits in bone marrow samples attained by aspiration or biopsy. An attempt was made to correlate the semiquantitative estimation of bone marrow iron with the peripheral blood values connected with iron deposits.

RESULTS

Anaemia was present in 15 patients, but in most cases MCV and serum iron were normal. Iron deposits in bone marrow aspirate could be evaluated only in one patient as in the remainders no material was obtained. The semiquantitative estimation of iron in bone marrow biopsy samples showed diminished or absent deposits in 15 cases (75%). In contrast, none of the patients had decreased serum ferritin levels. No correlation was found between bone marrow iron and the peripheral blood values related to iron deposits.

CONCLUSION

Most IM patients have decreased bone marrow iron deposits at diagnosis. However, as in chronic myelogenous leukaemia and in essential thrombocytopenia, such finding does not mean a true iron deficiency status.