Papillary cystadenocarcinoma of the submaxillary gland. A rare diagnosis

The authors describe a case of a "separate" type of salivary adenocarcinoma-like tumor. The growth is described as a papillary cystadenocarcinoma of the submaxillary gland, which should be distinguished from degenerate adenolymphoma. This malignant tumor, which remains "enclosed" until late, grows slowly and should be checked regularly over a protracted period of time following surgical excision performed in accordance with cancer therapy specifications.     

An unusual case of benign hibernoma in the paediatric age group

An unusual case of congenital benign hibernoma, in the submandibular region, in a 2.5 years old girl, is reported, who presented with a progressively increasing neck swelling. A CAT scan of neck revealed a superficial and deep low density mass. Surgical excision revealed a benign hibernoma. A 3-year follow-up shows no recurrence.     

Morphometric analysis of the roots and neural foramina of the lumbar vertebrae

BACKGROUND: There have been few anatomic studies on the foramina and roots of the lumbar region, and those available in human specimens are usually based on computed tomography and magnetic resonance imaging methods. METHODS: Using the recent breakthroughs in microscopic anatomic dissections, the roots and vertebral foramina of the lumbar region were examined in 15 cadavers. Morphometric analysis of the roots and vertebral foramina of 80 lumbar vertebral objects was conducted. RESULTS: The transverse and sagittal diameters of the lumbar intervertebral foramina were measured at each vertebral level. The median diameter of the lumbar neural foramina was 8.8 +/- 1.7 mm for the transverse and 19.4 +/- 2.7 mm for the sagittal planes. The widest median diameter of roots was 3.9 mm in the L4 root, and the narrowest was 3.3 mm in the L1 root. CONCLUSION: Quantitative measurements of the diameters of the neural foramina and roots of the lumbar region in anatomic dissection models may provide a deeper understanding about the pathologies of this region and influence the success of surgical interventions.     

Acute toxicity of cadmium,zinc, and cadmium-zinc mixtures toDaphnia magna

Experiments were performed in flow-through apparatus to determine the acute toxicity of zinc, cadmium, and their mixtures toDaphnia magna in order to compare sensitivity ofDaphnia relative to that of other organisms and to determine if the metal mixture behaves differently than expected on the basis of single metal experiments. Dosage-mortality curves are derived forDaphnia populations exposed to zinc and cadmium for 36, 48, 60, 72, and 96 hr periods. Similar curves are derived forDaphnia exposed to equally potent mixtures of zinc and cadmium as calculated from initial experiments and forDaphnia exposed to equal concentration mixtures of the metals. Cadmium is more toxic than zinc, but zinc-cadmium mixtures are less toxic than expected.Daphnia magna is considerably more sensitive to these metals than are other invertebrates and vertebrates previously studied. This study demonstrates errors which can arise in attempts to set water quality criteria based upon short term studies of organisms with long life spans.This work was supported by a Quebec Minister of Education grant to P. D. Anderson, by a Quebec scholarship to E. N. Attar, and by a National Science and Engineering Council grant to E. J. Maly. We thank G. Leduc and P. D. Anderson for helpful criticism and discussion     

Palliation of esophageal carcinoma with intraluminal tubes: experience with 30 patients.

Between 1968 and 1978, 26 patients with carcinomas of the thoracic esophagus and 4 with adenocarcinomas involving the esophagogastric junction were treated by the insertion of indwelling intraluminal (endoesophageal) tubes. Four different types of tube were inserted by the pull-through technique. Thirteen of the 30 patients died in the hospital within 30 days. However, among the 20 patients who did not have neoplasms of the upper third of the thoracic esophagus or who had not had a prior resection, only 5 died. The principal cause of death was aspiration pneumonia. Survival averaged 2.5 months. Four patients survived 5 to 7 months. Deglutition was adequate in most patients but was not as satisfactory as after esophagogastrectomy. Our best results were obtained in patients with carcinoma of the middle or lower third of the esophagus, with or without an esophagorespiratory fistula, who had not had a previous resection.     

Malignant histiocytic lymphoma (reticulum cell sarcoma) in pregnancy.

Malignant histiocytic lymphoma has been rarely found during pregnancy. The present case appears to be the eleventh reported in the world literature. Its management represented a diagnostic challenge because of the unusual symptoms. Surgery, external irradiation, and chemotherapy produced excellent and lasting results with complete recovery of the mother and an unaffected offspring.     

Silencing p21(Waf1/Cip1/Sdi1) expression increases gene transduction efficiency in primitive human hematopoietic cells

Adult hematopoietic and other tissue stem cells have highly constrained cell cycling that limits their susceptibility to standard gene therapy vectors, which depend upon chromosomal integration. Using cytokine cocktails to increase transduction efficiency often compromises subsequent stem cell function in vivo. We previously showed that p21(Waf1/Cip1/Sdi1) (p21) mediates stem cell quiescence in vivo and decreasing its expression ex vivo leads to an expansion of stem cell pool in vivo. Here, we report that application of p21 specific siRNA increased the gene transduction efficiency in hematopoietic stem cells while preserving cell multipotentiality. Both types of siRNA, synthesized siRNA and transcribed shRNA, reduced p21 expression in target cells by 85-98%. The effect of RNAi in these cells was transient and the level of p21 mRNA returned to base line 14-28 days after siRNA treatment. This brief interval of reduction, however, was sufficient to increase transduction efficiency to two- to four-fold in cell cultures, and followed by a seven- to eight-fold increase in mice. The RNAi treated, lentivector-transduced CD34+ cells retained multipotentiality as assessed in vitro by colony formation assay and in vivo by NOD/SCID mouse transplantation assay. Reduction of p21 resulted in an increased chromosomal integration of lentivector into target cellular DNA. Taken together, both synthesized and transcribed siRNA knocked down p21 expression in human CD34+ hematopoietic stem/progenitor cells. Silencing p21 expression increased gene transduction efficiency and vector integration while retaining stem cell multipotentiality. Thus, RNAi targeting of p21 is a useful strategy to increase stem cell gene transfer efficiency. Decreasing p21 expression transiently while increasing gene-transfer vector integration may ultimately facilitate clinical applications of gene therapy.