Biology of Hyalomma impeltatum (Acari: Ixodidae) under laboratory conditions

Completion of the life cycle of Hyalomma impeltatum Schulze & Schlottke required an average of 108 d at 26 +/- 1 degree C, 92-96% RH, and 12:12 (L:D) photoperiod. Weights of unfed larvae, nymphs, and females were 0.02, 0.16, and 15.4 mg, respectively, and increased 23-, 164-, and 55-fold, respectively, as a result of feeding on guinea pigs. Larvae and adults exhibited host-seeking behavior less than 1 d after hatching and molt, respectively; nymphs exhibited host-seeking behavior 2.9 d after molt. The mean (+/- SE) feeding period as larvae was 5.9 (+/- 2.23) d, nymphs 6.7 (+/- 1.10) d, and females 8.0 (+/- 0.19) d. Larvae molted 12.4 (+/- 0.26) d and nymphs molted 28.9 (+/- 0.22) d after engorgement. A sex ratio of 1.26:1 female/male was determined from emerged adults. Females began oviposition 8.9 (+/- 0.22) d after engorgement and produced 10,680 (+/- 300) eggs per female. Egg hatch was 84% (+/- 2.68) after an incubation period of 32.8 (+/- 0.19) d. Females converted 55% of engorged weight into eggs and produced 12,475 (+/- 188) eggs/g of engorged body weight. A freshly laid egg on the first day of oviposition weighted 47.7 (+/- 0.65) micrograms. An inverse relationship between egg weight and rate of egg production was observed.     

Iron metabolism and cell membranes. III. Iron-induced alterations in HeLa cells.

The morphologic characteristics of acute iron loading were studied in HeLa cells incubated in an iron-enriched Eagle's medium containing 500 mug/ml of iron. Chemical studies showed that ferritin synthesis was rapidly induced and the concentration of intracellular ferritin increased up to 72 hours. Closely coupled with an increase in HeLa cell ferritin was a marked decrease in the rate of cell multiplication. The significant ultrastructural findings of iron-induced HeLa cell injury are characterized by the appearance of both autophagic multivesicular and residual bodies over the first 72 hours of iron incubation. The prominence of multivesicular bodies was noted after only 4 hours' incubation, with iron and myelin figures first appearing after 6 hours. Thus, the partial arrest of cell multiplication was associated with an increase in cytoplasmic residual bodies containing iron and other debris. The distribution of intracellular ferritin within HeLa cells differs significantly from the distribution described previously in hepatic parenchymal cells. In HeLa cells, ferritin particles were confined to lysosomal vesicles and were not identified in cell sap, endoplasmic reticulum, or Golgi apparatus.     

Iron deficiency in children undergoing adenoid-tonsillectomy.

Following a preliminary study of peripheral blood values in 30 children undergoing tonsillectomy and adenoidectomy, a biochemical survey of the iron status of another 108 children also undergoing this operation was made utilizing an automated micro-method. It was shown that 8.4% of these children were frankly iron-deficient but there was no statistical relationship between the levels of serum iron and iron-binding capacity, the incidence of throat infections and the levels of the plasma immunoglobulins. Assessment of all children undergoing this operation for the presence of iron deficiency is advocated as a possible routine screening procedure.     

Synchronous radiation and cytotoxic chemotherapy for locally advanced or recurrent squamous cancer of the vulva.

Between July 1987 and September 1991 a program of external beam radiation and synchronous, radiopotentiating chemotherapy was employed to treat 25 women with locoregionally advanced or locoregionally recurrent squamous cancer of the vulva. Of 18 previously untreated patients, 1 was Stage II, 10 were Stage III, 6 were Stage IVA, and 1 was Stage IVB. Reasons for patient referral for nonsurgical management included the presence of initially unresectable disease (5 patients), disease extent which would have necessitated partial or total exenteration if treated surgically (9 patients), disease extent predictive of inadequate surgical margins (less than 1 cm gross margin) if treated by less than exenterative surgery (8 patients), and severe comorbid illness precluding surgical management (3 patients). Complete clinical response was obtained in 16 of 18 previously untreated patients (89%) and in 4 of 7 patients with recurrent disease following vulvar surgery (57%). Of 20 patients achieving a complete clinical response, 3 patients have relapsed within the irradiated volume at 11, 38, and 48 months following completion of treatment. Fourteen patients remain alive and continuously cancer free from 2-52 months after completion of treatment (median follow-up 24 months). This experience suggests that initial management with radiation and chemotherapy may offer some patients with locally advanced squamous cancer of the vulva an alternative to exenterative surgery and may hold curative potential for some patients with surgically unresectable or medically inoperable disease.     

Diagnostic performance of the hearing handicap inventory for the elderly (screening version) against differing definitions of hearing loss

The diagnostic performance of the Hearing Handicap Inventory for the Elderly--Screening Version (HHIE-S) was evaluated against five definitions of hearing loss in 178 elderly subjects screened in primary care. Hearing loss was assessed by pure-tone audiometry. Using a score of greater than 8 as a cut point, the HHIE-S had sensitivities ranging from 53 to 72% and specificities ranging from 70 to 84% with the different definitions. The HHIE-S receiver-operating characteristics and likelihood ratios were similar regardless of hearing loss definition used. The HHIE-S is a valid, robust test for identifying hearing-impaired elderly, irrespective of the audiometric definition used to finally diagnose hearing difficulties.