Giovanni Barsotti

Development of 3D wet-spun polymeric scaffolds loaded with antimicrobial agents for bone engineering

Three-dimensional wet-spun microfibrous meshes of a star poly(∈-caprolactone) were developed as potential scaffolds endowed with antimicrobial activity. The in vitro release kinetics of the meshes, under physiological conditions, was initially fast and then a sustained release for more than one month was observed. Cell cultures of a murine pre-osteoblast cell line showed good cell viability and adhesion on the wet-spun star poly(∈-caprolactone) fiber scaffolds. These promising results indicate a potential application of the developed meshes as engineered bone scaffolds with antimicrobial activity.

Occurrence of fungi from conjunctiva of healthy horses in Tuscany, Italy

The fungal flora of the normal conjunctival fornix has been described for many animal species (Urban et al., 1972; Samuelson et al., 1984; Moore et al., 1988; Davidson et al., 1994; Cooper et al., 2001) and many environmental factors, such as age, geography, habitat and husbandry are reported to influence its composition (Samuelson et al., 1984; Andrew et al., 2003). Equine keratomycosis can be caused by saprophytic fungi following an underlying corneal pathology or improper use of topical antibiotics and/or topical corticosteroids (Andrew et al., 1998; Brooks, 1999). Knowledge of differences in geographic prevalence of fungi and their frequency in the conjunctiva of the horse could allow the identification of risk factors for the development of keratomycosis. The purpose of the present paper was to culture, describe and quantify moulds and yeasts from the conjunctival fornix of healthy horses living in Tuscany (Italy), and to identify the most common fungal species.

Safety and Efficacy of Bilateral Topical Application of Rocuronium Bromide for Mydriasis in European Kestrels (Falco tinnunculus)

Abstract The avian iris is mainly composed of striated muscle fibers, and the topical parasympatholytic drugs used in mammals to induce pupil dilation are ineffective in birds. The achievement of mydriasis in conscious birds is only possible by using neuromuscular blocking agents such as curariform drugs. To determine the efficacy of the neuromuscular blocking agent rocuronium bromide as a mydriatic agent in European kestrels (Falco tinnunculus) and to assess possible adverse effects due to its use, 10 kestrels received a single topical instillation with a pipette of 0.12 mg of rocuronium in each eye (total dose, 0.24 mg/bird). Pupil diameter was measured with a pupillary gauge, and pupillary light reflex was assessed by using a standard light source from time zero (Tbase) to 250 minutes after application (T250). Baseline pupil size (Tbase) was 3.30 (0.71) mm in both eyes. Maximal mydriasis was achieved at T90 minutes with a mean (SD) pupillary diameter of 6.30 (0.42) mm and 6.35 (0.41) mm in the right eye and left eye, respectively. At the dose used, rocuronium bromide induced a consistent bilateral simultaneous mydriasis without noticeable adverse effects, and it can be considered a reliable and safe topical mydriatic agent in kestrels.

Mydriatic effect of topically applied rocuronium bromide in tawny owls (Strix aluco): comparison between two protocols

OBJECTIVE To evaluate the mydriatic efficacy of a neuromuscular blocking agent (rocuronium bromide) applied topically to only one eye of nocturnal birds of prey and to assess for any general and/or local adverse effects due to its use. Animal studied  Twelve healthy adult tawny owls (Strix aluco) were randomly divided in two groups. PROCEDURES Six birds (Group 1) received a single dose of 0.35 mg of rocuronium bromide. The second group of subjects (Group 2) received two doses of 0.35 mg of rocuronium bromide (total 0.70 mg/eye). In both groups, the curariform agent was instilled topically. Pupil diameter was measured with a pupillary gauge in 10 min intervals for a total of 100 min and then every 20 min for a total of 240 min. The assessment of the pupillary light reflex was performed using a standard light source during pupillary size recording. RESULTS Maximal pupillary diameter was 11.5 ± 0.3 mm for Group 1 and 11.0 ± 0.6 mm for Group 2 and no statistically significant differences were detected among the two groups. The maximal pupillary diameter was achieved at T80 for Group 1, and at T60 for Group 2. A complete fundus examination was possible on all treated eyes of subjects of both groups. The drug did not cause any noticeable adverse effects in any of the examined birds. CONCLUSION Results of the present study suggest that a single topical administration of 0.35 mg of rocuronium bromide to the eyes of healthy tawny owls results in sufficient mydriasis to allow for a complete examination of the fundus.

Evaluation of the endotracheal tube cuff pressure resulting from four different methods of inflation in dogs

OBJECTIVE To evaluate the endotracheal tube cuff pressure achieved by four different inflation methods. STUDY DESIGN Prospective clinical study. ANIMALS Eighty client owned dogs. METHODS After anaesthesia induction, endotracheal intubation was performed using plastic or silicone tubes. A clinician unaware of tube type inflated the cuff by simple digital palpation (method A), thereafter the cuff was deflated and inflated again by a second clinician who tried to reproduce a previously learned cuff pressure of between 19 and 24 mmHg (method B). During method C the cuff was inflated to the minimum occlusive volume at an airway pressure of 20 cm H(2) O, and in method D the cuff was incrementally deflated until an audible air leak could be heard from the oral cavity at an airway pressure of 25 cm H(2) O. For all the methods, an operator recorded the actual cuff pressure obtained using a manometer. Heart rate, respiratory rate and mean arterial pressure were monitored throughout the procedure. RESULTS The mean inflation pressure for plastic tubes was 56 ± 28 mmHg for method A, 20 ± 9 mmHg for method B, 35 ± 32 mmHg for method C and 46 ± 39 mmHg for method D. Pressures using silicone tubes were significantly higher than for plastic tubes, the mean registered pressures being 79 ± 39, 33 ± 16, 77 ± 50 and 92 ± 56 mmHg for methods A, B, C and D. CONCLUSIONS AND CLINICAL RELEVANCE None of the methods evaluated in this study can be considered effective for inflating the endotracheal tube cuff to within the optimal range when using silicone tubes. Direct measurement of the cuff pressure with a manometer is therefore recommended.

Bilateral mydriasis in common buzzards (Buteo buteo) and little owls (Athene noctua) induced by concurrent topical administration of rocuronium bromide

OBJECTIVE To evaluate the achievement of a bilateral mydriasis in raptors induced by a concurrent topical application of rocuronium bromide and to assess any side effects that might result from its use. Animals studied  Ten healthy adult common buzzards (Buteo buteo) and 10 healthy adult little owls (Athene noctua). PROCEDURES Common buzzards (Group 1) received a single dose of 0.40 mg of rocuronium bromide in each eye (total dose 0.80 mg/bird), whereas the little owls (Group 2) received a single dose of 0.20 mg in each eye (total dose 0.40 mg/bird). The drug was topically instilled in all the birds of both groups. The pupil diameter was measured with a pupillary gauge and the assessment of the pupillary light reflexes was performed using a standard light source. RESULTS Maximal pupillary diameter was 8.10 ± 0.56 mm in the right eye and 8.05 ± 0.59 mm in the left eye for Group 1 and 10.0 ± 0.75 mm in both eyes for Group 2. No statistical differences were evidenced between the achieved pupillary diameters of both eyes in each group. The maximal pupillary diameter was achieved at T110 min and T40 min for Groups 1 and 2, respectively. The drug did not cause noticeable adverse effects in the examined birds. CONCLUSIONS A single concurrent topical administration of rocuronium bromide to the eyes of the examined birds induced a complete bilateral mydriasis in both eyes without causing any adverse effect.

Tailored star poly (ε-caprolactone) wet-spun scaffolds for in vivo regeneration of long bone critical size defects:

One of the most challenging requirements of a successful bone tissue engineering approach is the development of scaffolds specifically tailored to individual tissue defects. Besides materials chemistry, well-defined scaffold’s structural features at the micro- and macro-levels are needed for optimal bone in-growth. In this study, polymeric fibrous scaffolds with a controlled internal network of pores and modelled on the anatomical shape and dimensions of a critical size bone defect in a rabbit’s radius model were developed by employing a computer-aided wet-spinning technique. The tailored scaffolds made of star poly(ε-caprolactone) or star poly(ε-caprolactone)–hydroxyapatite composite material were implanted into 20-mm segmental defects created in radial diaphysis of New Zealand white rabbits. Bone regeneration and tissue response were assessed by X-rays and histological analysis at 4, 8 and 12 weeks after surgery. No signs of macroscopic and microscopic inflammatory reactions were detected, and the developed scaffolds showed a good ability to support and promote the bone regeneration process. However, no significant differences in osteoconductivity were observed between star poly(ε-caprolactone) and star poly(ε-caprolactone)–hydroxyapatite scaffolds. Long-term study on implanted star poly(ε-caprolactone) scaffolds confirmed the presence of signs of bone regeneration and remodelling, particularly evident at 24 weeks.

Ocular abnormalities in healthy Standardbred foals

OBJECTIVE To determine the prevalence and describe ocular abnormalities in healthy Standardbred foals within 48 h of birth. ANIMALS One hundred and two neonatal foals. PROCEDURES All foals had an unassisted delivery. On the basis of physical examination and the results of hematological and biochemical parameters, all foals were unaffected by systemic diseases. A complete ophthalmic examination was performed within 48 h of birth. Foals with ocular hemorrhages were re-examined weekly until the abnormalities were resolved. RESULTS 65/102 (63.7%) foals did not show ocular abnormalities, while in 37/102 (36.3%) cases, ocular abnormalities were present. Retinal and subconjunctival hemorrhages were recorded in 19/102 (18.6%), and in 13/102 (12.7%), respectively. In 4/102 (3.9%) animals, an entropion of the lower eyelid was present. Only one foal (1%) showed a congenital nuclear unilateral cataract. No other ocular abnormalities were detected. However, all foals showed various degrees of remnants of hyaloid system. One week after the first ocular examination, retinal hemorrhages had resolved in 100% of the eyes, whereas subconjunctival hemorrhages had disappeared in all eyes by the second week following the first examination. CONCLUSIONS The acquired ocular lesions observed with relatively high frequency in the examined healthy Standardbred foals were ocular hemorrhages, which always showed a good outcome. Although these abnormalities were present at birth, they were not considered strictly congenital but likely acquired during parturition. Instead, congenital ocular abnormalities were rarely diagnosed, and the entropion of the lower eyelid was the most common disease in the breed.

Seasonal prevalence of fungi in the conjunctival fornix of healthy cows during a 2-year study

OBJECTIVE The aims of the present paper were to: (i) identify and quantify conjunctival fungi isolated from healthy cows; (ii) verify the influence of different methods of farm management on the prevalence (percentage of positive cultures for each fungal species per farm) of conjunctival fungi. MATERIAL AND METHODS Forty Friesian and twenty Limousin female cows aged 1-10 years stabled in three farms with different managements (farm 1: cows housed strictly indoors; farm 2: cows housed outside during the day and inside the stall during the night; farm 3: cows housed strictly outdoors) were investigated for conjunctival fungal flora. Air and food were also tested. Specimens were collected every season during a 2-year study. Identification of colonies of filamentous fungi was achieved to the genus level on the basis of macro- and microscopic features. RESULTS The total number of eyes positive for fungi ranged from 85 to 100% at farm 1, from 65 to 95% at farm 2, and from 55 to 95% at farm 3. Fungi most frequently isolated from conjunctival fornix were Cladosporium spp. and Penicillium spp. Statistical analysis did not show any differences in fungal prevalences among the three farms during the same season. Some fungal species were consistently isolated while others were intermittently isolated. CONCLUSIONS Fungi found in the conjunctival fornix of cows might represent transient seeding from the environment, as suspected in other species. The prevalence of conjunctival fungal organisms is not different in cattle housed indoors vs. outdoors.

Conjunctival bacterial and fungal flora in clinically normal sheep.

Objectives The aim was to identify conjunctival bacterial and fungal flora in clinically normal sheep. Design Prospective study. Setting Tuscany. Participants 100 eyes from 50 adult Massese female sheep were examined. The sheep included in the study were considered free of anterior ophthalmic abnormalities. Primary and secondary outcome measures Bacteria were identified by morphological assessment, Gram staining, biochemical tests. Identification of filamentous fungi was achieved at the genus level, and Aspergillus species were identified based on keys provided by other authors. Yeast colonies were highlighted, but not identified. Results Positive cultures were obtained from 100/100 eyes for bacteria, and from 86/100 eyes for fungi. A total of 14 types of bacteria and 5 types of fungi were isolated. Yeasts were isolated from 13/100 eyes. The most frequent fungal isolates were saprophytic fungi. Conclusions Conjunctival bacterial and fungal flora of clinically normal eyes were reported in sheep. The positivity obtained for conjunctival bacteria was higher compared to findings in the literature by other authors in the same species (100 per cent v 40 per cent), while our results were in line with a recent work performed on mouflons (Ovis Musimon) with a 100 per cent positivity for bacterial conjunctival fornix. In our survey, Gram-positive species were prevalent, as reported by other authors in different species. Few data are available in the literature regarding conjunctival fungal flora in healthy small ruminants. The prevalence of conjunctival fungal flora in this study was higher than findings reported in mouflons (86 per cent v 45 per cent). Differences in fungal prevalence may be due to different methods of managing herds, though further studies are required to verify this hypothesis. The similarities in bacterial and fungal isolates between sheep and mouflons suggest a genera pattern of conjunctival colonisation by bacteria and fungi.