Spectroscopic properties of lead fluoroborate glasses doped with ytterbium

A new lead fluoroborate glass (PbO-PbF2-B2O3) doped with ytterbium (Yb:PbFB) is presented. Samples with different concentrations of Yb3+ were produced and had their emission cross-sections, fluorescence lifetimes and minimum pump intensities determined. They have high refractive index of 2.2 and a density of 4.4 g/cm3. For a doping level of 1.153x1020 ions/cm3, the fluorescence lifetime, after excitation at 968 nm, is 0.81 ms, which is comparable to Yb:tellurite laser glass. Also, an emission band at 1022 nm is measured with emission cross-section of approximately 1.07x10-20 cm2 and fluorescence effective linewidth of 60 nm, which is comparable to Yb:phosphate laser glass.

Outbreak of poliomyelitis in Angola

Between January and June 1999, 1,100 suspected cases of poliomyelitis were reported in Angola. Poliovirus types 3 and 1 were isolated. Patients' ages ranged from 2 months to 14 years. Of the 588 patients whose vaccine status was known, 58 (9.9%) received >4 doses, 216 (36.7%) received 3 or 4 doses, 178 (30.3%) received 1 or 2 doses, and 136 (23.1%) had no history of vaccination. Civil conflict, economic decline, and crowded areas with scarce sanitation and poor water supply are the most important factors implicated in declining rates of routine vaccination, low population immunity, and intense wild poliovirus transmission. The socioeconomic situation and poor roads have created major difficulties for vaccination and surveillance. The Angolan outbreak has serious implications for the global eradication of poliomyelitis. Surveillance of acute flaccid paralysis remains essential in the assessment of strategies for eradication and interventions to interrupt wild poliovirus transmission.

Central nervous system (CNS) tuberculosis following allogeneic stem cell transplantation

Tuberculosis is an uncommon infectious complication after stem cell transplantation. We report a patient who presented with a brain mass, 3 months after pulmonary tuberculosis had been diagnosed and while he was receiving triple antituberculous therapy. He had extensive chronic GVHD. The diagnosis was made after biopsy of the lesion. The cerebral mass was excised, antituberculous treatment was maintained and the patient made a complete neurologic recovery. Six months later, he died of gram-negative septic shock. Mycobacterial infections should be considered in allograft recipients with chronic GVHD and solid lesions in the brain. Bone Marrow Transplantation (2000) 25, 567-569.

Supporting children with cystic fibrosis in school

Children with cystic fibrosis need support to benefit from a normal education. Liaison between the specialist nurse and school staff--teachers and nurses--can enable the school to provide this support.

Changing patterns in pediatric mortality, Maputo Central Hospital, Mozambique, 1980-1990

OBJECTIVES

To present an analysis of the Department of Paediatrics' statistics on hospital mortality, covering the period through 1980-1990.

METHODS

Basic information was recollected from logbooks of the Department's wards. Descriptive statistics are estimated on death and its main causes. The proportion of deaths in relation to total admissions and in relation to global in-hospital mortality are computed and their changes over time documented.

RESULTS

The data show an important decrease of in-hospital global mortality in spite of the increase of the number of admissions over time. The pattern of the main causes of death changed, and the authors postulate that the change is attributed to a dramatic change in the epidemiological pattern of childhood morbidity in Maputo City, especially due to measles vaccination. In parallel, the study suggests an increase in the prevalence of severe malnutrition.

CONCLUSIONS

Hospital statistics, while dependent on socio-economic conditions, can be significantly changed by Public Health interventions. Monitoring and analysing hospital statistics is important for documenting epidemiological changes, and also to suggest community interventions. From that point of view, epidemiological surveillance and hospital statistics are complementary.

Stachybotrys toxins. 1

Cultures of several isolates of Stachybotrys chartarum have produced a series of cytotoxic macrocyclic trichothecenes including two newly characterized congeners: isosatratoxin G and S-isosatratoxin H. Nine immunosuppressant phenylspirodrimanes (1-9) were isolated and characterized, the majority of which are newly reported compounds.

Acinar structure and function in canine pancreatic autografts with duct drainage into the urinary bladder

Autotransplants of pancreas in 8 dogs, with exocrine drainage into the urinary bladder, were stimulated in vivo with cholecystokinin-pancreozymin (CCK-PZ). Transplant biopsies, when compared with 6 normal pancreases, showed normal acinar structure by light and electron microscopy 13-18 months after initial surgery; 2 transplants with sutures unintentionally transecting ducts were fibrosed and had duct obstruction. After in vivo stimulation, the normal-appearing transplants produced a 7-fold increase in urinary amylase, and quantitative electron microscopy showed a 50% reduction in mature zymogen granules; there were no intracellular organelle abnormalities prior or subsequent to stimulation. Fibrosed transplants produced lesser urinary amylase both prior to and after stimulation. In vitro stimulation of grafts with normal structure increased amylase secretion from 1.5-2.1-fold. In vitro dose-response showed a maximum at 10(-9)M cholecystokinin-octopeptide (CCK-OP) in transplant and control. The in vivo stimulation is more responsive and may be useful for clinical monitoring of graft survival. In vivo stimulation occurred after induced urinary tract infection; because no pancreatitis ensued, a regimen of trophic stimulation by CCK-PZ was not contraindicated. The bladder tolerated exocrine drainage with no significant change, and bladder infection did not adversely affect the transplant. The islets appeared normal in the transplants by light and qualitative electron microscopic observation; fasting blood glucose and insulin values were normal during the 12-18-month follow-up. Bladder drainage of segmental grafts of pancreas provides a preparation with intact acinar-islet relationships; the present observations suggest that this may permit longer islet survival in the absence of acinar destruction and subsequent fibrosis.