Genetical analysis of visual system disorganizer (vid), a new gene involved in normal development of eye and optic lobe of the brain in Drosophila melanogaster

A neuroanatomical screening of a collection of P-element mutagenized flies has been carried out with the aim of finding new mutants affecting the optic lobe of the adult brain in Drosophila melanogaster. We have identified a new gene that is involved in the development of the adult axon array in the optic ganglia and in the ommatidia assembly. We have named this locus visual system disorganizer (vid). Reversional mutagenesis demonstrated that the vid mutant was the result of a P-element insertion in the Drosophila genome and allowed us to generate independent alleles, some of which resulted in semilethality, like the vid original mutant, while the others were completely lethal. A genetic somatic mosaic analysis indicated that the vid gene is required in the eye for its normal development by inductive effects. This analysis also suggests an inductive effect of the vid gene on the distal portion of the optic lobe, particularly the lamina and the first optic chiasma. Moreover, the absence of mutant phenotype in the proximal region of the optic ganglia, including the medulla, the second optic chiasma, and the lobula complex underlying mosaic eyes, is suggestive of an autonomously acting mechanism of the vid gene in the optic lobe. The complete or partial lethality generated by different mutations at the vid locus suggests that this gene's role may not be limited to the visual system, but may also affect a vital function during Drosophila development.

Treatment of onchocerciasis

Onchocerciasis ('river blindness') has for several centuries been the scourge of people living in certain areas of the world where the disease is endemic. The treatment available up to 10 years ago, diethylcarbamazine, had very severe secondary effects. The availability of ivermectin--a well tolerated and highly effective microfilaricidal drug--has completely changed this scenario. Ivermectin is now considered to be the drug of choice for the treatment of onchocerciasis. The prognosis for people with onchocerciasis has changed greatly. It is now possible to avoid the heavy infection loads seen previously, and patients, especially expatriates, may have their symptoms relieved by treatment. Ivermectin, used in mass treatment, may also improve the epidemiological situation, reducing the level of microfilariae in the skin of infected people and thus reducing the source for vector infestation. However, the treatment has to be repeated because the drug has no macrofilaricidal effect. Research today is focused on the finding of a drug able to destroy the adult worms that go on producing microfilariae for the length of their lives.

[Correlation between aortic transvalvular gradient obtained with Doppler ultrasonography and with hemodynamics study. Role of the underlying etiology]

In aortic stenosis, a good correlation was found between the gradients obtained by catheterization and Echo-Doppler. However, the correlation of these two methods in subgroups of patients with different etiologies of aortic stenosis is unknown. The aim of this study was to evaluate, whether the correlation between catheterization and Echo-Doppler was similar in patients with different etiologies of aortic stenosis. Patients with concomitant valvular disease were excluded. Only patients with a clearly defined etiology (based on clinical history, echocardiography, angiography and/or pathology) were included in this study. We evaluated 106 patients with aortic stenosis. Forty-nine patients had degenerative aortic stenosis, 32 bicuspid aortic stenosis and 25 rheumatic aortic stenosis. The percentage of male patients in each group were as follows: 57.1% in the denerative aortic group; 62.5% in the bicuspid aortic stenosis group; and 76% in the rheumatic aortic stenosis group. Mean age (years) was 69 +/- 6.7 in the degenerative aortic stenosis group, 58.1 +/- 7.5 in the bicuspid aortic stenosis group, and 64 +/- 7.1 in the rheumatic aortic stenosis group. In our study we found different correlations between the gradients obtained by the two methods-catheterization and Eco-Doppler-among the patients with different etiologies of aortic stenosis. The correlation coefficient (r2) was 0.54 (p < 0.001) in the rheumatic aortic stenosis group, 0.37 (p < 0.001) in the bicuspid aortic stenosis group and 0.21 (p = 0.001) in the degenerative aortic stenosis group. In conclusion, a good overall correlation was found between the two methods in aortic stenosis, however, this correlation is different in the three etiologies of aortic stenosis. The correlation is better in rheumatic valves, intermediate in bicuspid valves, and worse in degenerative valves. Changes in aortic valve morphology in these subgroups of patients are probably responsible for these different results.

[Familial cancer of the breast]

Genetic, cultural and environmental factors are influences shared in familial breast cancer. The objective of this study was to evaluate the prevalence of familial breast cancer and its association with social and clinical characteristics of women. A hospital-based descriptive study was made, and 300 patients with the diagnosis of breast cancer, made in 1992, were investigated. 17,4% of the women had a history of familial breast cancer. The presence of a positive history for familial breast cancer was associated with high social level for post-menopausal women. Age at diagnosis was older for women whose affected relative was their sister, not their mother. The need for the continuing efforts of epidemiologists, pathologists and geneticists to recognize the explanatory model of the disease is emphasized.

[Nutrition and bone mineral density in premenopausal women]

Environmental factors have an important role in osteoporosis. Diet and, in particular, nutrients like calcium, vitamin D or phosphorus were extensively studied as determinants of bone mineral density, but the results remain conflicting and there is no clear evidence for an independent effect of such factors in the bone density of premenopausal women. We studied 66 healthy premenopausal women (20-40 years-old) aiming to relate bone mineral density, as measured in three different sites (distal forearm, lumbar spine and femoral neck) using single X ray and dual energy X-ray absorptiometry, with nutritional intake as estimated by a semi-quantitative food frequency questionnaire. Demographic, anthropometric and other life style variables were also assessed. There was a significant correlation between distal forearm and femoral neck (r = 0.57) or lumbar spine (r = 0.45) bone mineral density. No significant effect of age was observed for distal forearm bone mineral density in these women. In a stepwise multiple linear regression model, evaluating the contribution of all the variables studied, only body mass index (p=0.038) and vitamin A ingestion (p = 0.020) had an independent contribution for the variation in distal forearm bone mineral density. Mean bone mineral density, assessed in the femoral neck (p = 0.003) or the lumbar spine (p = 0.056) was different across tertiles of alcohol ingestion, being higher in non-drinkers. However, among regular drinkers there was a significant positive correlation between alcohol ingestion and femoral neck bone mineral density (Spearman's r = 0.53, p = 0.015). This study shows that the effect of nutrition seems dependent on the anatomical site assessed and that there is a weak correlation between nutritional intake and the actual bone mineral density.

Down syndrome-critical region contains a gene homologous to Drosophila sim expressed during rat and human central nervous system development

Many features of Down syndrome might result from the overdosage of only a few genes located in a critical region of chromosome 21. To search for these genes, cosmids mapping in this region were isolated and used for trapping exons. One of the trapped exons obtained has a sequence very similar to part of the Drosophila single-minded (sim) gene, a master regulator of the early development of the fly central nervous system midline. Mapping data indicated that this exonic sequence is only present in the Down syndrome-critical region in the human genome. Hybridization of this exonic sequence with human fetal kidney poly(A)+ RNA revealed two transcripts of 6 and 4.3 kb. In situ hybridization of a probe derived from this exon with human and rat fetuses showed that the corresponding gene is expressed during early fetal life in the central nervous system and in other tissues, including the facial, skull, palate, and vertebra primordia. The expression pattern of this gene suggests that it might be involved in the pathogenesis of some of the morphological features and brain anomalies observed in Down syndrome.

p53 protein expression and nuclear DNA content in breast intraductal proliferations

Immunohistochemical analysis of the p53 gene protein and cytometric assessment of nuclear DNA were performed in a series of 51 cases of intraductal breast proliferation. The series included 22 cases of intraductal hyperplasia without atypia, 6 cases of intraductal hyperplasia with atypia, and 23 cases of pure intraductal carcinoma. Expression of p53 protein was detected in one case of intraductal hyperplasia without atypia (4.5 per cent), one case of intraductal hyperplasia with atypia (16.6 per cent) and six cases of intraductal carcinoma (26.0 per cent). No significant correlation was observed between p53 expression and histological subtype of intraductal carcinoma. Aneuploidy was demonstrated in two cases of intraductal hyperplasia with atypia (33.3 per cent) and in 18 cases of intraductal carcinoma (78.2 per cent). All cases of intraductal hyperplasia without atypia were euploid. No significant association was observed between p53 protein expression and ploidy in intraductal hyperplasia. The only case of intraductal hyperplasia without atypia positive for p53 was euploid, whereas the only p53-positive case of intraductal hyperplasia with atypia was aneuploid. Among the intraductal carcinomas, only the aneuploid cases showed positivity for p53, regardless of histological subtype. The results suggest that some of the changes observed in invasive breast carcinoma, such as p53 expression and aneuploidy, are already present in breast intraductal proliferation, especially in areas with atypia and in intraductal carcinoma. The expression of p53 in breast intraductal proliferation may reflect the acquisition of p53 gene mutations in cells unable adequately to repair DNA damage, with genomic instability which would lead to clonal expansion and putative evolution to invasive disease.

Empirical development of brief smoking prevention videotapes which target African-American adolescents

Two studies are described which provide evaluations for two brief videotapes developed as supplemental materials in the prevention of tobacco use among African-American adolescents. One videotape (the "soap opera") provides a more general audience-oriented presentation of prevention material and it was filmed primarily at a shopping mall, whereas the other videotape (the "rap") provides a "hip-hop generation" presentation, and it was filmed primarily at an outdoor hangout. The first study compared the two videotapes against each other. The second study compared the two videotapes combined in the same presentation, controlling for order of presentation, against a discussion group control. The results of the two studies indicated few differences in receptivity to the two videotapes among primarily African-American and Latino young adolescents. The rap videotape was rated as more accurate in its depiction of the African-American lifestyle, although both videotapes were equally liked. When shown together, the videotapes were not found to be superior in decreasing behavioral intention to smoke compared to a discussion group control. No change in trial of smoking was observed within or across conditions measured over a pre-post summer interval. These data suggest that "culturally sensitive" videotapes have no more of a short-term effect on youth than do other types of brief interventions which involve minority implementers.

[The Bland-White-Garland syndrome or an anomalous origin of the left coronary from the pulmonary artery. Apropos a case of a continuous murmur in an adult]

The authors report a case of anomalous origin of the left coronary artery from the trunk of pulmonary artery in an adult without significant symptoms, diagnosed by the presence of a continuous thoracic murmur. Because its low incidence and great mortality in the beginning of life, the appearance in the adult is extremely uncommon, especially without symptoms of cardiac failure, angina pectoris or myocardial infarction. In the present case, the patient was asymptomatic and was submitted to various echocardiograms before the diagnosis was suspected and confirmed with angiography. Surgical treatment was performed successfully with reimplantation of the anomalous vessel in the aorta.

[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)

[Treatment of acute promyelocytic leukemia with trans-retinoic acid. Experience of the Santa Maria Hospital, Medical School of Lisbon]

Acute promyelocytic leukemia (APL) is a rare subtype of acute myelogenous leukemia that is usually associated with a fatal hemorrhagic diathesis. All trans-retinoic acid (ATRA) is an active metabolite of vitamin A that differentiates the malignant cell clone, corrects the coagulopathy, and induces complete remission in the vast majority of patients with APL. Between June 1992 and September 1993, 8 patients with APL (4 previously untreated, 3 in first relapse and 1 in second relapse) received ATRA. Complete remission was achieved in 7 patients; in 5 with ATRA alone and in 2 with ATRA followed by cytotoxic chemotherapy due to the development of asymptomatic hyperleukocytosis. The earliest signs of response were the correction of the coagulopathy and an increase in the white blood cell count. Sequential morphological and immunophenotypical analyses of the bone marrow revealed differentiation of the malignant cell clone, in the absence of bone marrow hypoplasia. 4 of 5 patients treated only with ATRA until complete remission had late leukopenia. The most frequent adverse effects were dryness of skin and mucosae, hypertrigliceridemia and hypercholesterolemia, and a moderate increase in liver transaminases. An increase in the white blood cell count was common, and in two cases exceeded 35.0 x 10(9)/l. One of these patients developed multiple thrombosis of the extremities after cytotoxic chemotherapy. We frequently observed an increase in lactic dehydrogenase levels that was concomitant with the peak in the white blood cell count. The only patient on whom complete remission was not achieved was 60 years old, had chronic obstructive pulmonary disease, and died in the third week of therapy with a pulmonary distress syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)

An integrated YAC-overlap and 'cosmid-pocket' map of the human chromosome 21

We describe here the construction of an ordered clone map of human chromosome 21, based on the identification of ordered sets of YAC clones covering > 90% of the chromosome, and their use to identify groups of cosmid clones (cosmid pockets) localised to subregions defined by the YAC clone map. This is to our knowledge the highest resolution map of one human chromosome to date, localising 530 YAC clones covering both arms of the chromosome, spanning > 36 Mbp, and localising more than 6300 cosmids to 145 intervals on both arms of the chromosome. The YAC contigs have been formed by hybridising a 6.1 equivalents chromosome 21 enriched YAC collection displayed on arrayed nylon membranes to a series of 115 DNA markers and Alu-PCR products from YACs. Forty eight mega-YACs from the previously published CEPH-Genethon map of sequence tagged sites (STS) have also been included in the contig building experiments. A YAC tiling path was then size-measured and confirmed by gel-fingerprinting. A minimal tiling path of 70 YACs were then used as probes against the 7.5 genome equivalents flow sorted chromosome 21 cosmid library in order to identify the lists of cosmids mapping to alternating shared--non-shared intervals between overlapping YACs ('cosmid pockets'). For approximately 1/5 of the minimal tiling path of YACs, locations and non-chimaerism have been confirmed by fluorescence in situ hybridisation (FISH), and approximately 1/5 of all cosmid pocket assignments have independent, confirmatory marker hybridizations in the ICRF cosmid reference library system. We also demonstrate that 'pockets' contain overlapping sets of cosmids (cosmid contigs). In addition to being an important logical intermediate step between the YAC maps published so far and a future map of completely ordered cosmids, this map provides immediately available low-complexity cosmid material for high resolution FISH mapping of chromosomal aberrations on interphase nuclei, and for rapid positional isolation of transcripts in the highly resolved regions of genetic interest.

[Free thrombi in the left atrium. Report of a clinical case]

The authors describe a case of a floating thrombus in the left atrium, detected by a 2D echocardiography in a female patient suffering from dilated cardiomyopathy. At the follow-up, it was found that the mass was no longer detected inside the left atrium. This occurrence was not associated to any major embolic phenomena. A transesophageal echocardiographic study revealed the presence of a thrombus in the left atrial appendage.

[Spinal brucellosis. 4 years of experience]

The Authors retrospectively studied 17 patients who have been admitted to the Infectious Diseases Clinic of Coimbra University Hospital during a four year period and whose final diagnosis was brucellar spondylitis. Clinical, epidemiological, laboratory and imaging features are analyzed, as well as those related to the therapeutic schedules and outcome. Females were more often affected (70.58%) and the mean age was 53.35 +/- 13.82 years. Lumbar spine was most frequently involved and an unusual elevated incidence of paravertebral soft tissue swelling was noticed (23.52%). Two patients were also suffering from neurobrucellosis (11.76%). The preferred therapeutic schedule was rifampin and doxycycline and surgery was performed in one patient. Finally, several comments are made regarding basically the incidence, laboratory and imaging diagnosis, therapeutic aspects and evolution of the disease. The imaging similarities and differences between tuberculous, pyogenic and brucellar spondylitis are briefly approached.

Immunohistochemical analysis of ras oncogene p21 product in human gastric carcinomas and their adjacent mucosas

In an attempt to clarify the relationship between ras oncogene expression and the clinico-pathological features of malignant and pre-malignant lesions of the stomach we undertook the immunohistochemical study of the expression of ras gene p21 product in a series of eighty gastric carcinomas and their respective adjacent mucosas. In two cases the mRNA of Ha-ras was also studied by in situ hybridization. The majority of gastric carcinomas as well as their adjacent non-neoplastic mucosas expressed ras gene product. There was a significant relationship between the expression of ras gene p21 product and the morphologic pattern of the tumours. An enhanced ras expression was found in several conditions regarded as precursor lesions of intestinal and/or diffuse types of gastric carcinoma (dysplasia, foveolar hyperplasia and even the neck zone of normal-appearing gastric glands, namely in the mucosa adjacent to diffuse carcinomas). Ras expression was actually more prominent in most of these conditions than in their respective adjacent carcinomas. No significant relationship was found between ras expression and invasiveness of the wall, nodal metastases and venous invasion.

Amplification and overexpression of the EGF receptor and c-erbB-2 proto-oncogenes in human stomach cancer

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Familial gastric polyposis revisited. Autosomal dominant inheritance confirmed

We update and review a large pedigree originally described by Santos and Magalhães with familial gastric polyposis and a high incidence of gastric cancer. The present observation of male-to-male transmission of the disease clearly demonstrates the autosomal dominant pattern of inheritance. The histologic review of the polyps present in several members of the family allowed the diagnosis of hyperplastic polyposis. Eight members of the family (two with concomitant gastric pathology) have severe cutaneous psoriasis. This finding may represent the existence of two different disorders segregating in the family or, alternatively, pleiotropic manifestations of the same gene.

[Phlebectasis of the external jugular vein]

Phlebactasia of the external jugular vein is a rare nosological entity. Few reports appeared in the world literature. Clinically it presents as a cervical mass enlarging with a Valsalva maneuver. The Authors present one clinical case, emphasizing the possibilities of Computed Tomography (CT) in a precise diagnosis, etiological and topographical, without using other invasive modalities.

Cytology and development of a mycorrhiza-like infection in the gametophyte of Conocephalum conicum (L.) Dum. (Marchantiales, Hepatophyta)

An aseptate fungus associated with the gametophyte of the hepatic Conocephalum conicum (L.) Dum. was studied by light and electron microscopy. The fungus forms a highly branched mycelium external to the plant. Fungal hyphae colonize the smooth-walled rhizoids, through which they pass into the gametophyte parenchyma of the midrib. The fungus in the parenchyma is entirely intracellular. Vesicles are found in rhizoids and a few ventral layers of parenchyma cells. Prominent arbuscules develop in more internal cells from lateral branches of infecting hyphae that spread from cell to cell. Infected host cells show cytoplasmic proliferation, especially of ribosomes, Plastids and mitochondria, The arbuscules eventually degenerate leaving clumps of collapsed hyphae. Reinfection of cells with degenerate arbuscules was not observed. The ultrastructural and developmental characteristics of the fungus and its high cytological compatibility with the host are indicative of a well integrated symbiotic association similar to the vesicular-arbuscular mycorrhizas of higher plants.