730-nm optical parametric conversion from near- to short-wave infrared band.

A record 730 nm parametric conversion in silica fiber from the near-infrared to the short-wave infrared band is reported and analyzed. A parametric gain in excess of 30 dB was measured for a signal at 1300 nm (with corresponding idler at 2030 nm). This conversion was performed in a travelling single-pass one-pump parametric architecture and high efficiency is achieved by a combination of high peak power and a nonlinear fiber with a reduced fourth-order dispersion coefficient.

Prepubertal periodontitis affecting the deciduous and permanent dentition in a patient with cyclic neutropenia. A case report and discussion.

Neutropenia is a transient or chronic blood disorder characterized by a decrease in the number of circulating polymorphonuclear leukocytes (PMNs). Neutrophils are a major cellular defense against infection, and depletion of these cells is potentially fatal. Stomatitis and gingivitis frequently are seen in patients with neutropenia. Therefore, the diagnosis of severe oral pathoses of obscure origin must include a differential white blood cell count. The importance of the dentist's role is dramatically illustrated in the rare case reported here, since the oral condition was the reason for this patient's definitive blood work-up. The report illustrates the importance of the laboratory assessment in dental patients with unusual periodontal destruction or other inexplicable oral changes.

Neonatal leukemoid reaction. An isolated manifestation of mosaic trisomy 21.

A phenotypically normal neonate with an unexplained leukemoid reaction had a 46,XX/47,XX, +21 karyotype limited to the hemopoietic system. Although a self-limited myeloproliferative syndrome occurs in Down's syndrome, this case confirms that an identical disorder may develop in patients with mosaic trisomy 21 and no phenotypic stigmas of Down's syndrome. Chromosome analysis is a necessary adjunct to the examination of any neonate with an unexplained leukemoid reaction. The presence of trisomy 21 should lead to conservative management, unless there is life-threatening progression of the disease.

A new syndrome of refractory sideroblastic anemia with vacuolization of marrow precursors and exocrine pancreatic dysfunction.

In the past decade, we have studied four unrelated children with what we believe is a previously unreported disorder affecting the bone marrow and exocrine pancreas. During infancy these patients had the onset of severe, transfusion-dependent, macrocytic anemia plus a variable degree of neutropenia and thrombocytopenia. Their bone marrows had normal cellularity but were characterized by remarkable vacuolization of erythroid and myeloid precursors, hemosiderosis, and ringed sideroblasts. The vacuoles probably represented manifestations of cellular degeneration and death. In two patients, in vitro bone marrow cultures showed abnormal erythroid and myeloid progenitor cell growth and, in one child, abnormal vacuolated erythroid colonies. Family histories were unrevealing, parents were hematologically normal, and both sexes were involved. There was no evidence of specific nutritional deficiencies or exposure to agents associated with marrow vacuolization. A number of therapeutic interventions produced no effect. One child had clinical malabsorption. This child and one other had extensive pancreatic fibrosis at autopsy. The other two patients had findings indicating exocrine pancreatic dysfunction. Two children had splenic atrophy. This new syndrome, with associated bone marrow and exocrine pancreatic dysfunctions, differs in several respects from the syndrome of pancreatic liposis and neutropenia described by Shwachman et all and Bodian et al, and from other conditions with vacuolization of the marrow or sideroblastosis.