Type of closure prevents microbial contamination of cosmetics during consumer use.

The dispensing closure used for containers plays an important role in protecting cosmetics from in-use microbial contamination. This hypothesis was tested by aseptically packing unpreserved shampoo and skin lotion into containers with three different closure types which provided various degrees of protection against consumer and environmental microbial insults. Shampoo was packed in containers with slit-cap (n = 25), flip-cap (n = 25), or screw-cap (n = 28) closures. Skin lotion was packed in containers with pump-top (n = 21), flip-cap (n = 18), or screw-cap (n = 21) closures. The products were then used by volunteers under actual in-use conditions for 3 (shampoo) or 2 (skin lotion) weeks. After use, the products were evaluated for microbial contamination by using standard methods for enumeration and identification. The standard screw-cap closure provided only minimal protection against microbial contamination of both the shampoo (29% contamination incidence) and the skin lotion (71%). The slit-cap closure on the shampoo container and the flip-cap closure on the skin lotion container provided slightly enhanced degrees of protection (21 and 39% contamination incidence, respectively). The greatest amount of protection (i.e., lowest contamination incidence) was provided by the flip-cap closure for the shampoo container (0%) and the pump-top closure for the skin lotion container (10%). As a result, closure type plays an important role in protecting poorly preserved products from in-use microbial contamination.     

Type of closure prevents microbial contamination of cosmetics during consumer use

The dispensing closure used for containers plays an important role in protecting cosmetics from in-use microbial contamination. This hypothesis was tested by aseptically packing unpreserved shampoo and skin lotion into containers with three different closure types which provided various degrees of protection against consumer and environmental microbial insults. Shampoo was packed in containers with slit-cap (n = 25), flip-cap (n = 25), or screw-cap (n = 28) closures. Skin lotion was packed in containers with pump-top (n = 21), flip-cap (n = 18), or screw-cap (n = 21) closures. The products were then used by volunteers under actual in-use conditions for 3 (shampoo) or 2 (skin lotion) weeks. After use, the products were evaluated for microbial contamination by using standard methods for enumeration and identification. The standard screw-cap closure provided only minimal protection against microbial contamination of both the shampoo (29% contamination incidence) and the skin lotion (71%). The slit-cap closure on the shampoo container and the flip-cap closure on the skin lotion container provided slightly enhanced degrees of protection (21 and 39% contamination incidence, respectively). The greatest amount of protection (i.e., lowest contamination incidence) was provided by the flip-cap closure for the shampoo container (0%) and the pump-top closure for the skin lotion container (10%). As a result, closure type plays an important role in protecting poorly preserved products from in-use microbial contamination.     

Lack of cardiovascular tolerance during intravenous cocaine infusions in human volunteers

Acute tolerance to the cardiovascular effects of cocaine has been hypothesized from experiments in which the plasma concentrations of cocaine were rapidly changing. We studied the cardiovascular responses of 8 male human subjects for 4 hours following intravenous bolus doses of cocaine, and compared these to responses in the same subjects after intravenous bolus doses of cocaine followed by continuous intravenous infusions of cocaine designed to maintain steady state plasma levels of cocaine. We found little evidence of tolerance to the tachycardia and hypertensive effects of cocaine during a four hour exposure. Lack of tolerance to the cardiovascular effects of cocaine may be a factor in some types of cocaine related toxicity among cocaine abusers.     

Cerebrovascular effects of intravenous dopamine infusions in fetal sheep.

Preterm infants are often treated with intravenous dopamine to increase mean arterial blood pressure (MAP). However, there are few data regarding cerebrovascular responses of developing animals to dopamine infusions. We studied eight near-term and eight preterm chronically catheterized unanesthetized fetal sheep. We measured cerebral blood flow and calculated cerebral vascular resistance (CVR) at baseline and during dopamine infusion at 2.5, 7.5, 25, and 75 microg x kg(-1) x min(-1). In preterm fetuses, MAP increased only at 75 microg x kg(-1) x min(-1) (25 +/- 5%), whereas in near-term fetuses MAP increased at 25 microg x kg(-1) x min(-1) (28 +/- 4%) and further at 75 microg x kg(-1) x min(-1) (51 +/- 3%). Dopamine infusion was associated with cerebral vasoconstriction in both groups. At 25 microg x kg(-1) x min(-1), CVR increased 77 +/- 51% in preterm fetuses and 41 +/- 11% in near-term fetuses, and at 75 microg x kg(-1) x min(-1), CVR increased 80 +/- 33% in preterm fetuses and 83 +/- 21% in near-term fetuses. We tested these responses to dopamine in 11 additional near-term fetuses under alpha-adrenergic blockade (phenoxybenzamine, n = 5) and under dopaminergic D(1)-receptor blockade (SCH-23390, n = 6). Phenoxybenzamine completely blocked dopamine's pressor and cerebral vasoconstrictive effects, while D(1)-receptor blockade had no effect. Therefore, in unanesthetized developing fetuses, dopamine infusion is associated with cerebral vasoconstriction, which is likely an autoregulatory, alpha-adrenergic response to an increase in blood pressure.     

Prolonged intravenous infusions of LH-releasing hormone into normal men.

Five normal men received constant intravenous infusions of luteinizing hormone-releasing hormone (LH-RH), 0.2 mug/min, for 14-19 hours. Serum levels ofluteizining hormone (LH) revealed a biphasic pattern of increase, reaching maximal values by 4 hours after the infusions began, then remained near that level until the infusions ceased. Serum follicle stimulating hormone (FSH) levels rose gradually to maximal values by 6-13 hours and maintained this level until the end of the infusions. Testosterone (T) levels revealed gradual increases throughout the infusions. These results confirm an increase in serum T levels with prolonged endogenous gonadotrophin stimulation. This is in contrast to the inability of several previous studies to demonstrate an increase in T levels following the relatively short gonadotrophin elevation produced by single-shot LH-RH administration. The T increases produced, however, were quantitatively much less than those reported during prolonged LH-RH infusions in rams, suggesting that the human testis is less responsive to endogenous gonadotrophin stimulation than is that of the ram. In addition, prolonged LH-RH stimulation did not cause pituitary refractoriness in men as has been described in animals.     

Impact of prescribed cleaning and disinfectant use on microbial contamination in the home

Aims: To identify and quantify the presence of Escherichia coli, Staphylococcus aureus, Salmonella, hepatitis A and norovirus in households and to assess the effect of chlorine and quaternary ammonium–based disinfectants following a prescribed use. Methods and Results: Eleven sites distributed in kitchen, bathroom, pet and children′s areas of two groups of 30 homes each: (i) a nonprescribed disinfectant user group and (ii) a disinfectant protocol user group. During the 6‐week study, samples were collected once a week except for week one when sample collection occurred immediately before and after disinfectant application to evaluate the disinfectant protocol. The concentration and occurrence of bacteria were less in the households with prescribed use of disinfectants. The greatest reductions were for E. coli (99%) and Staph. aureus (99·9999%), respectively. Only two samples were positive for HAV, while norovirus was absent. Disinfection protocols resulted in a significant (P < 0·05) microbial reduction in all areas of the homes tested compared to homes not using a prescribed protocol. Conclusions: The study suggests that disinfectant product application under specific protocol is necessary to achieve greater microbial reductions. Significance and Impact of the Study: Prescribed protocols constitute an important tool to reduce the occurrence of potential disease‐causing micro‐organisms in households.     

The technique of obtaining germinating pollen without microbial contamination

Sterilizují se dospělé pra?níky roztoky Famoseptu nebo Chloraminu B. Po opláchnutí vodou se rychle vysu?í ve vakuu za nízké vlhkosti vzduchu. Z otev?ených pra?ník? se pyl vyklepává v jednoduchém za?ízení (obr. 1).     

The clinical use of desflurane.

Desflurane, a newly introduced potent, inhaled anesthetic, differs from its predecessors in having a lower solubility in blood and tissues. The lower solubility imparts a greater control to the maintenance of anesthesia and a more rapid elimination and recovery from anesthesia. In other respects, the pharmacological properties of desflurane resemble those of its sister anesthetic, isoflurane, currently the most widely-used potent anesthetic in this and other countries. The qualitative exceptions to this resemblence are that desflurane is more pungent and produces a greater increase in heart rate, particularly at deeper levels of anesthesia.     

Wipe-rinse technique for quantitating microbial contamination on large surfaces.

The Orca Basin is a hypersaline depression in the northern Gulf of Mexico with anoxic conditions observed in the lower 200 m of the water column. Measurements of adenosine 5′-triphosphate, heterotrophic potential, and uridine uptake made above and across the interface into the anoxic zone revealed the presence of an active microbial population approximately 100 m above the interface. Biomass and activity decreased at and just below the interface but increased near the bottom, consistent with similar observations made in the Cariaco Trench. The maximum adenosine 5′-triphosphate concentration above the interface of 5.9 ng/liter (2,173 m) is about eight times greater than the value found in oxygenated waters of corresponding depth in the absence of an anoxic zone. The maximum adenosine 5′-triphosphate concentration in the anoxic zone is approximately 15 times greater than that found in oxygenated water of similar depth, suggesting anoxia will support the development of a larger bacterial population. Our findings suggest that autotrophic bacteria may be the dominant physiological group in the region just above the interface.     

The clinical use of antishock trousers.

In 34 (71%) of 48 consecutive patients who were in shock (systolic blood pressure less than 80 mm Hg) the application of antishock trousers by ambulance personnel or emergency room staff produced rapid increases of 20 mm Hg or more in the systolic blood pressure. The trousers were applied to a 49th patient only to stabilize a fractured femur. The most common indication for the device was shock resulting from hemorrhage in the upper gastrointestinal tract. Of 20 such patients, 17 (85%) responded rapidly, as did all 5 patients who were treated for a ruptured abdominal aortic aneurysm. The proper application and management of antishock trousers are simple enough for use in the field, although deflation of the device before adequate replacement of fluids would precipitate a return to a state of shock.     

石油烃污染及修复过程中的微生物分子生态学研究进展

针对环境中广泛存在的石油烃污染问题,从分子生态学的角度总结石油烃降解过程中的微生物生态学研究进展。着重介绍分子生态学的研究方法及与石油烃降解相关的降解基因和基因芯片的最新研究进展,同时对存在的问题和今后的研究方向进行总结。     

Formation of 13,14-dihydro-prostaglandin E1 during intravenous infusions of prostaglandin E1 in patients with peripheral arterial occlusive disease.

Formation of 13,14-dihydro-prostaglandin (PG) E1 during intravenous infusions of PGE1 in patients with peripheral arterial occlusive disease was investigated. Using both high performance liquid chromatography (h.p.l.c.) combined with radioimmunoassay and gas chromatography/triple stage quadrupole mass spectrometry (GC/MS/MS) basal levels of 13,14-dihydro-PGE1 were found to be close to or below the detection limits of the assay methods. Levels of the PGE1 metabolite increased significantly during the infusion periods and decreased after their end. Since 13,14-dihydro-PGE1, in contrast to its precursors 15-keto-PGE1 and 15-keto-13,14-dihydro-PGE1, is biologically active, its formation could contribute to the beneficial effects of PGE1 administered intravenously in patients with peripheral arterial occlusive disease.     

Release of microbial contamination from fractured solids

Estimation of the probability of release of microbial contamination from the interior of solids upon fracture due to impact is essential to the formulation of planetary quarantine and spacecraft sterilization requirements. A model system was designed in which known concentrations of bacterial spores were incorporated in methyl methacrylate plastic. Pieces of plastic were fractured in a uniform manner exposing interior surface areas of consistent and measurable size. Known surface areas were incubated in sets of 20 culture tubes containing liquid growth medium. The subsequent occurrence of visible growth expressed as percent of tubes positive was interpreted as an estimate of the probability of release of at least one viable micro-organism.From these experiments probability of release as a function of microbial concentration in plastic was estimated for exposed interior surface areas of 30.6, 61.2, 91.8 or 122.4 mm². Good agreement of the empirical results with a theoretical mathematical model of the probability of release of contamination from solids was demonstrated. Analysis of the data using the maximum likelihood procedure provided a means of calculating a proportionality constant representing the effective thickness of the exposed area and the characteristics of the recovery procedure.