Expression of CD4 on peripheral blood granulocytes. a novel finding in a case of myelodysplastic syndrome in association with t(5;12)

Myelodysplastic syndromes (MDS) are associated with cell maturation defects that can manifest as abnormal surface antigen expression. We describe a patient with refractory anemia with excess blasts, who presented with infection and extensive dysplastic features in peripheral blood granulocytes. The granulocytes expressed CD11b, CD13, CD15, CD33, and CD43. The granulocytes also expressed CD4 antigen. Cytogenetic analysis showed a clonal t(5;12)(q33;p13). The patient improved on antibiotics with partial improvement in the dysplastic features. However, shortly after, the patient experienced paravertebral extramedullary blast transformation followed by a leukemia phase of acute monoblastic leukemia. The patient died a few days later. This is the first report describing anomalous expression of CD4 on granulocytes in MDS. Since the breakpoint on chromosome 12 is near the CD4 gene, which is mapped to 12p12, we hypothesize that dysregulation of the CD4 gene may have occurred resulting in its persistent expression on mature and maturing granulocytes.     

The genetic toxicology of metal compounds: II. Enhancement of ultraviolet light-induced mutagenesis in Escherichia coli WP2

Salts of metals which are carcinogenic, noncarcinogenic, or of unknown carcinogenicity were assayed for their abilities to modulate ultraviolet (UV)-induced mutagenesis in Escherichia coli WP2. In addition to the previously reported comutagenic effect of arsenite, salts of three other compounds were found to enhance UV mutagenesis. CuCl2, MnCl2 (and a small effect by KMnO4), and NaMoO4 acted as comutagens in E coli WP2, which has wild-type DNA repair capability, but were much less comutagenic in the repair deficient strain WP2s (uvrA). The survival of irradiated or unirradiated cells was not affected by these compounds. No effects on UV mutagenesis were seen for 16 other metal compounds. We suggest that the comutagenic effects might occur either via metal-induced decreases in the fidelity of repair replication or (in the case of CuCl2) via metal-induced depurination.     

Molecular and functional characterization of a mutant allele of the mitogen-activated protein-kinase geneSLT2(MPK1) rescued from yeast autolytic mutants

 We have further characterized the functionality of the Saccharomyces cerevisiae gene SLT2(MPK1), coding for a MAP-kinase homolog essential for cell integrity, which is involved in the Pkc1p signalling pathway. This gene was isolated on the basis of its capacity to complement the thermosensitive-autolytic, osmotic-remediable phenotype of lyt2 mutants. Both slt2Δ and lyt2 mutants displayed a caffeine-sensitive phenotype consisting of cell lysis that was not dependent on temperature. Caffeine concentrations affecting the growth of these mutant strains were dependent on the genetic background, the SSD1 allele being very significant in this regard. The SLT2 allele of several lyt2 strains was both rescued and amplified by PCR. The recovered allele was shown to be non-functional as it could not complement the lytic phenotype of both deletion (slt2Δ) and lyt2 strains. After nucleotide sequencing of the recovered allele, we found that the defect of lyt2 mutants consists in a substitution of an aspartic acid for a glycine at position 35 of the amino-acid sequence of Slt2p. Gly35 is the third glycine of a glycine cluster (Gly-X-Gly-X-X-Gly), a conserved region in protein kinases and other nucleotide-binding proteins. Received: 13 October/27 November 1995     

Induction of ovulation in rabbits by pure urinary Iuteinizing hormone

In 18-week-old nulliparous rabbit dose, ovulation was inducedwith 50 IU of pure urinary luteinizing hormone (LH; LHgroup),or 50 IU of ohuman chorionic gonadotrophin (HCG; HCG group),in order to detemine the effect of these treatments on 17-oestradioland progesterone concentrations, and on oocyte and embryo quality.Luteinizing follicles, recovered oocytes, progesteronoe concentrationand grade 5 embryos were significantly reduced when pure urinaryLH was used. Statistically significant correlations were found:(i) between oestradiol concentration and number of degeneratedoocytes in both groups (positive); (ii) between oestradiol concentrationand grade 1 and 2 embrayos (negative), and grade 5 embryos (positive)in the HCG group; (iii) between progesteronoe concentrationand metaphase II oocytes(negatice), and between progesteroneand grade 5 sembryos (positive), in the HCG group; and (iv)between progesterone and oestradiol concentrations (negative)in the LH group. It seems that the oestrsdiol to progegsteroneratio improves during the early luteal phase when ovulationis induced with LH, and that oestradiol and progesterone concentrationscould play a role in dtermining oocyte and embryo quality     

Thymic masses on MR imaging

MR imaging is an excellent technique for identifying and defining the extent of thymic tumors. T1-weighted spin-echo MR images (e.g., 600/15 [TR/TE]) best demonstrate tumor extent, and T2-weighted images (e.g., 2500/90 [TR/TE]) help differentiate "cystic" from solid thymic masses. Cyst formation and/or hemorrhage appear as areas of high signal intensity (greater than that of fat) on T2-weighted images. Focal areas of low signal intensity (less than that of muscle) correspond pathologically to fibrous capsules and septa, air, or calcification. In this report, the MR appearance of the normal thymus is reviewed briefly, and the gamut of abnormal thymic masses on MR is illustrated.     

24-h pH monitoring is necessary to assess acid reflux suppression in patients with Barrett's oesophagus undergoing treatment with proton pump inhibitors

BACKGROUND: Control of acid reflux is the main objective of treatment for Barrett's oesophagus. However, as these patients have a reduced sensitivity to acid reflux, disappearance of symptoms may not correlate with efficient control of acid reflux. The aim of this study was to determine in a group of patients with Barrett's oesophagus whether treatment with proton pump inhibitors suppressed pathological acid reflux once the symptoms of reflux had been controlled and the associated inflammatory lesions cured. METHODS: Eighteen consecutive patients with Barrett's oesophagus were studied, all of whom presented with heartburn. Twenty-four-hour oesophageal pH monitoring before treatment showed pathological acid reflux in all cases: median percentage of total time with pH less than 4, 22 (range 8-52) per cent. All patients received proton pump inhibitors (dose 20-60 mg/day) until symptoms were controlled. RESULTS: While on therapy, pH was reduced (median percentage of total time with pH less than 4, 3 versus 22 per cent; P < 0.001). However, three patients had persistent pathological rates of acid reflux. CONCLUSION: Disappearance of symptoms is not a good indicator of control of pathological acid reflux in patients with Barrett's oesophagus. Twenty-four-hour pH monitoring should be performed for proper adjustment of the dose of medication.     

A to Z: Vitamin A and zinc,the miracle duo

Dietary micronutrients such as vitamins and trace minerals are known modulators of host immune responses against common pathogens. In this respect, vitamin A and zinc have recently received increased attention. Severalin vivo andin vitro studies suggest that vitamin A may be a critical player in the mucosal immune responses in the respiratory and gastrointestinal tracts, particularly in undernourished children. The effect may be mediated primarily by stabilization of the membrane of mucosal epithelial cells, as well as enhanced leukocyte functions. The beneficial effect of vitamin A therapy in reducing measles-associated morbidity and mortality suggests its crucial role in defenses against viral pathogens. Zinc is also known affect leukocyte functions such as phagocytosis and T-lymphocyte-mediated immune responses. However, unlike vitamin A, zinc has been investigated primarily for its effects on bacterial infections. Dietary supplementation or therapeutic treatment with vitamin A and zinc may be a cheap yet effective means of preventing or treating infections in highly susceptible populations. Additional studies, however, are required to better define the types of pathogens and the specific human populations that may benefit from such therapy.     

Esophagogastrectomy for adenocarcinoma of the cardia. Ten years' experience and current approach.

During a 10-year period, 94 surgical resections for adenocarcinoma of the cardia (75 "curative" and 19 palliative) were performed using three primary approaches: Group I (46 curative, 14 palliative), esophagogastrectomy performed through a left thoracotomy or left thoraco-abdominal incision; Group II (17 curative, 4 palliative), resection done through two separate incisions (abdominal and thoracic) with delayed reconstruction between two and three months later; and Group III (12 curative, 1 palliative), resection, also through abdominal and thoracic incisions, with simultaneous reconstruction. Operative mortality in the 75 procedures done for cure was 19.5%, 18%, and 8.3% in Groups I, II, and III, respectively. Microscopic residual tumor at the line of resection was 56%, 12%, and 8%. Free margins less than 3 cm had the same local recurrence rate (21%, 6%, and 8%) within 18 months as did margins with residual microscopic tumor. The length of time from operation to first regular meal was 12, 110, and 7 days, respectively. Wide resection with subtotal esophagectomy and simultaneous reconstruction is advocated.