Neuralgia braquial amiotrófica bilateral que evoluciona a esclerosis lateral amiotrófica / Bilateral amyotrophic brachial neuralgia that progresses to become amyotrophic lateral sclerosis

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[Hyperhomocysteinemia as a risk factor for central retinal vein thrombosis in a young patient]. / Hiperhomocistinemia como un factor de riesgo para la trombosis de la vena central de la retina en un paciente joven.

INTRODUCTION: Central retinal vein thrombosis (CRVT) is a multifactorial disease and known risk factors include high blood pressure, diabetes mellitus, hypercholesterolemia and primary open-angle glaucoma. Yet in patients below the age of 60, a state of hyperviscosity and hypercoagulability in the absence of other vascular risk factors are important factors, as is hyperhomocysteinemia, an independent risk factor for venous thromboses. Homocysteine is an essential amino acid produced by the transmethylation of methionine. It can be remethylated using enzymes that require folate and cobalamin to re-form methionine or to catabolize for cystathionine beta-synthetase, which is dependent on pyridoxine to form cysteine. Hyperhomocysteinemia can give rise to a dysfunction in the endothelium of the vessel, with a proliferation of vascular smooth muscle and prothrombotic homostatic changes. CASE REPORT: A male, aged 33, with no vascular risk factors except cigarette smoking who presented a sharp drop in visual acuity in the right eye. An ophthalmological examination revealed the presence of CRVT, which was confirmed by fluorescein angiography. The results of all analytical and imaging studies conducted while the patient was in hospital were negative. Later analytical monitoring showed a moderate increase in homocysteine. CONCLUSION: From a survey of the literature we have found an important relation between CRVT and hyperhomocysteinemia, which has been noted as a potential risk factor and which requires therapy.

[Deferred Horner syndrome following thoracoplasty]. / Sindrome de Horner diferido tras toracoplastia.

INTRODUCTION: Horner syndrome (HS) involves an injury affecting the ocular sympathetic nerve, which gives rise to myosis, palpebral ptosis and enophthalmos, and is accompanied by hemifacial anhidrosis in its complete forms. Its extension means that its involvement can occur in different structures and as a result of different medical and surgical processes. CASE REPORT: We describe the case of two patients who developed a subacute form of HS without involvement of the sweating process and which was not accompanied by any other clinical features affecting the orbit, neck, brain, spinal cord or of a radicular nature. Both of them had been submitted to thoracoplasty as therapy for tuberculosis over 30 years earlier. The complementary studies that were conducted did not reveal involvement of the ocular sympathetic nerve anywhere other than in the pleura. CONCLUSIONS: The lesion would have been produced in the endothoracic fascia, where the cervical sympathetic chain is closely related to the apical pleura, and the physiopathological mechanism would be fibrosis of the aforementioned structures. Many reports have been published that describe the onset of HS as an acute complication following thoracic surgery, but its late development is infrequent.

Trisomy rescue by postzygotic unbalanced (X;14) translocation in a girl with dysmorphic features.

In this report we present the clinical features and molecular and cytogenetic findings in a female with partial trisomy 14q. Molecular and cytogenetic studies allowed us to determine that the extra 14q material (of paternal origin) was translocated postzygotically onto the maternal X chromosome. Consequently, only the derivative X chromosome was inactivated, although inactivation apparently did not spread over the entire chromosome 14q. This partial inactivation makes the present case unusual, giving rise to phenotypic features absent in other patients with partial trisomy 14q, typically restricted to the distal part of the chromosome.

A new case of partial trisomy 3(q25----qter) in a newborn.

A description of a female newborn with some physical stigmata presenting a partial trisomy for 3(q25----qter) is given. The additional material is located at the distal end of the short arm of chromosome 15 as the result of a maternal t(3;15) (q25:p13). Some characteristics of the proband were similar to those described for the 3(q21----qter) trisomy.

The use of bromodeoxyuridine labeling in the human lymphocyte HGPRT somatic mutation assay.

The autoradiographic assay developed by Strauss and Albertini (1979) to quantitate human in vivo somatic mutation at the hypoxanthine guanine phosphoribosyl-transferase locus uses tritiated thymidine to identify mutant cells by their ability to pass through 'S' phase in the presence of 6-thioguanine. An alternative method, based on the incorporation of bromodeoxyuridine (BrdUrd) into the DNA of proliferative cells, followed by differential staining with the fluorescence-plus-Giemsa method, was used to identify 3 classes of lymphocyte nuclei: (a) small darkly stained nuclei, (b) large, reddish-colored nuclei with an apparent nucleolus, and (c) large, bluish-colored nuclei. By double labeling with BrdUrd and tritiated thymidine, it was determined that only the nuclei of the third class had incorporated BrdUrd. These results demonstrate that the technique used for sister-chromatid differentiation can be used to detect putative HGPRT mutants and to determine variant frequencies at the HGPRT locus.

Inhibition of protein synthesis in cell cultures by vanadate and in brain homogenates of rats fed vanadate.

Following the observation of polysome disaggregation by vanadate, when Neuro-2a cells were incubated with vanadate, incorporation of 3H-leucine into protein was markedly inhibited. The inhibition of protein synthesis was dependent on vanadate concentration and on time of incubation. Inhibition of cell growth was also observed. Simultaneous measurements on vanadate-treated cells showed decreased Na,K-ATPase activity. Rats given sodium vanadate as their sole drinking fluid also showed an inhibition of brain protein synthesis (18 and 20% after 30 and 60 days, respectively, of treatment). Possible implications of the inhibition of Na,K-ATPase and of protein synthesis by vanadate are discussed.