In vitro and in vivo killing of ocular Demodex by tea tree oil

AIMS

To compare the in vitro killing effect of different agents on Demodex and to report the in vivo killing effect of tea tree oil (TTO) on ocular Demodex.

METHODS

Survival time of Demodex was measured under the microscope. Sampling and counting of Demodex was performed by a modified method.

RESULTS

Demodex folliculorum survived for more than 150 minutes in 10% povidone-iodine, 75% alcohol, 50% baby shampoo, and 4% pilocarpine. However, the survival time was significantly shortened to within 15 minutes in 100% alcohol, 100% TTO, 100% caraway oil, or 100% dill weed oil. TTO's in vitro killing effect was dose dependent. Lid scrub with 50% TTO, but not with 50% baby shampoo, can further stimulate Demodex to move out to the skin. The Demodex count did not reach zero in any of the seven patients receiving daily lid scrub with baby shampoo for 40-350 days. In contrast, the Demodex count dropped to zero in seven of nine patients receiving TTO scrub in 4 weeks without recurrence.

CONCLUSIONS

Demodex is resistant to a wide range of antiseptic solutions. Weekly lid scrub with 50% TTO and daily lid scrub with tea tree shampoo is effective in eradicating ocular Demodex.

Contribution of dietary and newly formed arachidonic acid to human milk lipids in women eating a low-fat diet

BACKGROUND

Polyunsaturated fatty acids in milk are derived from direct intestinal absorption, endogenous synthesis, or maternal body stores. Arachidonic acid (AA) intake is frequently low in undernourished women, but milk secretion of this fatty acid is similar to that in well-nourished women.

OBJECTIVE

The objective was to evaluate the contribution of dietary and endogenously synthesized AA to its total secretion in the milk of women eating a low-fat diet.

DESIGN

Ten lactating women who habitually ate a low-fat diet (17% of energy) received 2.5 mg [(13)C]linoleic acid (LA)/kg body wt orally 5 mo postpartum. LA and AA concentrations and (13)C enrichment were measured in milk samples collected before and after the tracer application. Total lipid, LA, and AA contents were determined in diet composites. Fatty acids were assessed by gas chromatography and (13)C enrichment by isotope ratio mass spectrometry.

RESULTS

The cumulative 72-h recovery of [(13)C]LA in milk was 16.3 +/- 6.4% of the dose; only 0.01% of the label was found as [(13)C]AA. The calculated transfer of dietary LA and AA into milk was 32.8 +/- 18.0% and 11.8 +/- 6.6%, respectively. AA originating from conversion of dietary LA contributed only 1.1% to the total milk AA secreted.

CONCLUSIONS

Little milk AA originates from conversion of LA; 70% of LA and 90% of AA secreted in milk were not derived from direct intestinal absorption. Our results suggest that maternal body stores are the major source of milk LA and AA in these women.

[Evolution of the prevalence of bedsores in the Hospital of Navarra]

INTRODUCTION

The rates of incidence and prevalence of patients with sores in hospital are indicators of nursing care quality. The aim of this study is to evaluate such prevalence in the last two years (1997-1998), comparing the patients with sores, the evaluation of the risk of developing sores, and the factors associated with their development.

MATERIAL AND METHODS

A transversal study was made, in which the subjects under study were all of the patients hospitalised in the Hospital of Navarra on the day set for the study. The study gathers the variables of sex, age, unit of hospitalisation, date of admission and date of the study, presence and number of sores, their development in or outside the hospital, evaluation of risk on admission and evaluation of risk on the day of the study (according to the modified Braden scale).

RESULTS

The prevalence of patients with sores was 8.9 per 100 patients hospitalised in 1997 and 5.1 in 1998. The difference is statistically significant with a value of p=0.025. Age, the classification of patients within those of risk, and the time of hospital stay are factors related to the development of sores.

CONCLUSIONS

The factors associated with the development of sores detected in the study lead us to be more attentive in our vigilance of the patients that show them. The follow up of the prevalence and incidence of bedsores in hospitals is an instrument that makes it possible to continue improving understanding, prevention and treatment of such lesions in patients.

An outbreak of enterotoxaemia caused by Clostridium perfringens type D in goats in Patagonia

Forty-four of a flock of 117 angora goats in the Rio Negro province of Argentina died within four days. Most of the animals died shortly after the onset of clinical signs, but in a few the clinical course lasted for several days. Post mortem the small and large intestines were filled with watery contents, blood and fibrin clots, and there were numerous ulcers on the mucosa. Small areas of malacia were observed histologically in the brain. Clostridium perfringens type D in pure culture was isolated from the kidneys and gut contents of the affected animals. Epsilon toxin was identified by the mouse seroneutralisation test in the supernatant solution from cultures of these isolates and in the intestinal contents of the affected animals. Heavy infestations with coccidia, nutritional and environmental stress, and an anthelmintic overdose were possible predisposing factors for the outbreak.