Nano-engineering of ketorolac tromethamine platforms for ocular treatment of inflammatory disorders

Aim: The development and optimization of Ketorolac tromethamine-loaded polylactic-co-glycolic acid nanoparticles (KT-NPs) for the treatment of inflammatory processes of the eye. Materials & methods: KT-NPs were developed by factorial design and characterized by assessing their physicochemical properties. Biopharmaceutical behavior studies, ocular tolerance, anti-inflammatory efficacy and bioavailability tests were performed on pigs. Results: Optimized KT-NPs of 112 nm, narrow distribution with encapsulation efficiency near 100% were obtained. KT release followed the Weibull model and there was significantly greater retention in the cornea and sclera than in the commercial reference. KT-NPs showed no signs of ocular irritancy and similar anti-inflammatory efficacy to the commercial reference. Conclusion: KT-NPs were a suitable alternative for the treatment of inflammatory disorders of the anterior and posterior segments of the eye as an alternative to conventional topical formulations.

Endogenous Antioxidant Cocktail Loaded Hydrogel for Topical Wound Healing of Burns

The main goal of this work is the study of the skin wound healing efficacy of an antioxidant cocktail consisting of vitamins A, D, E and the endogenous pineal hormone melatonin (MLT), with all of these loaded into a thermosensitive hydrogel delivery system. The resulting formulation was characterized by scanning electron microscopy. The antioxidant efficacy and microbiological activity against Gram positive and Gram negative strains were also assayed. The skin healing efficacy was tested using an in vivo model which included histological evaluation. Furthermore, atomic force microscopy was employed to evaluate the wound healing efficacy of rat skin burns through the determination of its elasticity at the nanoscale using force spectroscopy analysis. The resulting hydrogel exhibited sol state at low temperature and turned into a gel at 30 ± 0.2 °C. The hydrogel containing the antioxidant cocktail showed higher scavenging activity than the hydrogel containing vitamins or MLT, separately. The formulation showed optimal antimicrobial activity. It was comparable to a commercial reference. It was also evidenced that the hydrogel containing the antioxidant cocktail exhibited the strongest healing process in the skin burns of rats, similar to the assayed commercial reference containing silver sulfadiazine. Histological studies confirmed the observed results. Finally, atomic force microscopy demonstrated a similar distribution of Young's modulus values between burned skin treated with the commercial reference and burned skin treated with hydrogel containing the antioxidant cocktail, and all these with healthy skin. The use of an antioxidant cocktail of vitamins and MLT might be a promising treatment for skin wounds for future clinical studies.

Melatonin nanogel promotes skin healing response in burn wounds of rats

Aim: Development of a melatonin nanogel intended for wound healing (WH) application. Materials & methods: The main components of the nanogel were poloxamer 407, chitosan and hyaluronic acid. The nanogel was characterized by the assessment of physical interactions, swelling, wettability, rheological properties and internal structure. The drug release, antimicrobial efficacy against different strains and biocompatibility with human keratinocytes were also tested. Finally, the WH efficacy was evaluated in rats. Results: The nanogel showed optimal physicochemical properties and an internal network of interconnected channels from which melatonin was released following first order kinetics. Antimicrobial activity was similar to commercial reference material and it promoted epidermis growth with evident wound contraction. Conclusion: Melatonin nanogel can be proposed as a promising system for WH.

New Nanotechnologies for the Treatment and Repair of Skin Burns Infections

Burn wounds are highly debilitating injuries, with significant morbidity and mortality rates worldwide. In association with the damage of the skin integrity, the risk of infection is increased, posing an obstacle to healing and potentially leading to sepsis. Another limitation against healing is associated with antibiotic resistance mainly due to the use of systemic antibiotics for the treatment of localized infections. Nanotechnology has been successful in finding strategies to incorporate antibiotics in nanoparticles for the treatment of local wounds, thereby avoiding the systemic exposure to the drug. This review focuses on the most recent advances on the use of nanoparticles in wound dressing formulations and in tissue engineering for the treatment of burn wound infections.

Single shot spinal anesthesia with very low hyperbaric bupivacaine dose (3.75 mg) for hip fracture repair surgery in the elderly. A randomized, double blinded study

PURPOSE

Single shot spinal anesthesia is used worldwide for hip fracture repair surgery in the elderly. Arterial hypotension is a frequent adverse effect. We hypothesized that lowering local anesthetics dose could decrease the incidence of arterial hypotension, while maintaining quality of surgical anesthesia.

METHODS

In a randomized double blinded study, 66 patients over the age of 65 years, with hip fracture needing surgical repair, were assigned to B0.5 group 7.5mg hyperbaric bupivacaine 5mg/ml (control group), and B0.25 group 3.75mg hyperbaric bupivacaine 2.5mg/ml (study group). Sensory and motor block level, and hemodynamic parameters including blood presure, heart rate and vasopressor dose administration were registered, along with rescue anesthesia needs, the feasibility of surgery, its duration, and regression time of sensory anesthesia to T12.

RESULTS

After exclusions, 61 patients were included in the final analysis. Arterial hypotension incidence was lower in the B0.25 group (at the 5, 10, and 15min determinations), and a lower amount of vasopressor drugs was needed (mean accumulated ephedrine dose 1.6mg vs. 8.7mg in the B0.5 group, p<0.002). Sensory block regression time to T12 was shorter in the B0.25 group, mean 78.6±23.6 (95% CI 51.7-110.2)min vs. 125.5±37.9 (95% CI 101.7-169.4)min in the B0.5 group, p=0.033. All but one patient in the B0.25 group were operated on under the anesthetic procedure first intended. No rescue anesthesia was needed.

CONCLUSION

Lowering bupivacaine dose for single shot spinal anesthesia for hip fracture repair surgery in elderly patients was effective in decreasing the occurrence of arterial hypotension and vasopressor use, while intraoperative quality remained.

[Open surgery and endovascular treatment on the descending thoracic aorta: 15 years' experience]

OBJECTIVE

Outcomes of surgical treatment of the descending thoracic aorta have improved markedly, although high associated morbidity and mortality continue to be a concern. Endovascular treatments are therefore attractive alternatives to open surgery. We compared outcomes of endovascular treatment to outcomes of open surgery on both aortic segments.

MATERIAL AND METHODS

Retrospective study of patients treated for descending thoracic and thoracoabdominal aorta disease by means of open surgery or endovascular treatment in our hospital between 1995 and 2009. We analyzed preoperative characteristics, intraoperative variables, and postoperative results in both groups.

RESULTS

We retrieved the cases of 22 patients, 10 who underwent open surgery and 12 who received endovascular treatment. Surgery was indicated to treat aneurysm (40%), aortic dissection (30%), or both (30%) in the open surgery group. In the endovascular treatment group, 66.7% had aneurysm, 33.3% dissection, and 0% both. Trauma was involved in 20% of the open surgeries and 16.7% of the endovascular procedures. Forty percent of the open surgery cases and 16.2% of the endovascular interventions were emergencies. Patient age was the only statistically significant between-group difference in preoperative characteristics. Postoperative complication rates were similar. Significant differences were observed in duration of surgery, lengths of critical care unit and total hospital stays, and intubation time (P < .05).

CONCLUSIONS

The incidence of postoperative complications in the group of patients undergoing open surgery on the descending thoracic aorta was similar to incidences reported by other hospitals with moderate caseloads. A trend toward reduced morbidity and mortality in the endovascular treatment group was observed, and this group had significantly shorter times of intubation and lengths of critical care unit and hospital stays.

Awareness with recall during general anaesthesia: a prospective observational evaluation of 4001 patients

BACKGROUND

We have prospectively evaluated the incidence and characteristics of awareness with recall (AWR) during general anaesthesia in a tertiary care hospital.

METHODS

This study involves a prospective observational investigation of AWR in patients undergoing general anaesthesia. Blinded structured interviews were conducted in the postanaesthesia care unit, on postoperative day 7 and day 30. Definition of AWR was 'when the patient stated or remembered that he or she had been awake at a time when consciousness was not intended'. Patient characteristics, perioperative, and drug-related factors were investigated. Patients were classified as not awake during surgery, AWR, AWR-possible, AWR-not evaluable. The perceived quality of the awareness episode, intraoperative dreaming, and sequelae were investigated. The anaesthetic records were reviewed to search for data that might explain the awareness episode.

RESULTS

The study included 4001 patients. Incidence of AWR was 1.0% (39/3921 patients). If high risk for AWR patients were excluded, the incidence was 0.8%. After the interview on the seventh day, six patients denied having been conscious during anaesthesia; hence, the incidence of AWR in elective surgery was 0.6%. Factors associated with AWR were: anaesthetic technique incidence of 1.1% TIVA-propofol vs 0.59% balanced anaesthesia vs 5.0% O2/N2O-based anaesthesia vs 0.9% other anaesthetic techniques (mainly propofol boluses for short procedures), P=0.008; age (AWR 42.3 yr old vs 50.6 yr old, P=0.041), absence of i.v. benzodiazepine premedication (P=0.001), Caesarean section (C-section) (P=0.019), and surgery performed at night (P=0.013). More than 50% of patients reported intraoperative dreaming in the early interview, mainly pleasant. Avoidable human factors were detected from the anaesthetic records of most patients. Subjective auditory perceptions prevailed, together with trying to move or communicate, and touch or pain perception.

CONCLUSIONS

A relatively high incidence of AWR and dreams during general anaesthesia was found. Techniques without halogenated drugs showed more patients. The use of benzodiazepine premedication was associated with a lower incidence of AWR. Age, C-section with general anaesthesia, and surgery performed at night are risk factors.

[Anesthesia for carotid paraganglioma exeresis. Report of 3 cases]

This report of carotid paraganglioma excision in three patients discusses differential diagnosis, preoperative assessment, preoperative embolization of the tumor, monitoring of anesthesia including cerebral oximetry, and postoperative complications. We consider cerebral protection to be essential during carotid paraganglioma surgery. Such protection may be provided by drugs such as sodium thiopental and by temporarily shunting the internal carotid artery. Preoperative angiography is also important for evaluating retrograde circulation through Willis's polygon and to examine the arteries irrigating the tumor. Information thus obtained helps establish the need for presurgical embolization of the tumor, thereby possibly reducing the risks, such as obstructive hematoma that are inherent to the procedure. Finally, in our opinion, full monitoring should include cerebral oximetry so that possible complications can be detected and resolved.

Patch sampling behaviour and future foraging expectations in Argentine ants, Linepithema humile

Nests of Argentine ants, L. humile, were exposed to pairs of foraging patches of varying quality. These patches varied from never having food to having food for 4 h every day. After 15 days, colonies were allowed an added access to a new patch. The new patch, however, never contained food. The sampling behaviour of nests towards the initial patches and the new patch suggested that the nests were using a sampling rule based on maximizing net benefits of finding food minus the cost of sampling. The behaviour of the nests towards the new patch was also significantly affected by what the foraging workers had previouisly encountered in the foraging patches. The behaviour of the L. humile colonies is similar in pattern to what would result by Bayesian updating of expectations for success in novel foraging opportunities. These data are the first suggestions of such an ability in an insect. Copyright 1998 The Association for the Study of Animal Behaviour Copyright 1998 The Association for the Study of Animal Behaviour.

Trichotillomania and self-esteem: a survey of 62 female hair pullers

BACKGROUND

The psychological features of trichotillomania have received little empirical attention, despite the fact that sufferers commonly report negative self-image to be one of the most disturbing aspects of the disorder. We conducted the current study to identify specific factors that predict self-esteem problems in hair pullers.

METHOD

Sixty-two women with trichotillomania or repetitive hair pulling completed self-report forms assessing factors possibly related to self-esteem in hair pullers. The survey included questions related to demographics, hair-pulling symptoms, mood and anxiety symptoms, and body image concerns.

RESULTS

Self-esteem did not appear to be directly related to age at onset of hair pulling or severity of hair loss. However, self-esteem was related to level of depression, frequency of hair pulling, level of anxiety, and body dissatisfaction unrelated to hair pulling.

CONCLUSION

Several factors, including the frequency of hair pulling, are associated with low self- esteem in patients with trichotillomania. Specific efforts should be made to address these issues in treatment.