The simple and effective choice for treatment of chronic calcaneal osteomyelitis: neurocutaneous flaps

The authors describe their experience with the use of distally based saphenous and sural neurofasciocutaneous flaps for the treatment of calcaneal osteomyelitis in nine cases. Aggressive débridement of all nonviable and poorly vascularized tissue and coverage with a distally based neurofasciocutaneous flap were coupled with a thorough antibiotic course in all cases. The deepithelized peripheral parts of all flaps were buried in the bone cavities after bone débridement. Follow-up periods ranged from 15 to 27 months. All flaps survived completely. All of the wounds except one healed completely. These flaps have adequate blood flow for the management of chronic bone infections. They also have many advantages, such as easy quick elevation, short operative time, and acceptable donor-site morbidity. Moreover, patients treated with neurocutaneous flaps do not require debulking procedures or special shoes. Reconstruction with neurocutaneous flaps after radical débridement is a versatile alternative to the use of local or distant muscle flaps and calcanectomy procedures for patients with osteomyelitis of the os calcis.     

Habropetaline A,an antimalarial naphthylisoquinoline alkaloid from Triphyophyllum peltatum

The isolation, structural elucidation, and antiprotozoal activities of habropetaline A, a novel naphthylisoquinoline alkaloid from Triphyophyllum peltatum, are described. This alkaloid had previously only been identified on line, by the LC-MS/MS-NMR-CD triad, in the crude extract of the rare and difficult-to-provide related plant species Habropetalum dawei, whose small quantities available had not permitted to isolate the compound. As predicted by quantitative structure-activity relationship (QSAR) investigations, habropetaline A exhibits strong antimalarial activity against Plasmodium falciparum, while it is inactive against other protozoal pathogens (Trypanosoma brucei rhodesience, T. cruzi, and Leishmania donovani).     

Effects of inflammation and antiinflammatory treatment on serum trace elements concentrations

We investigated the serum concentrations of zinc and copper during the inflammatory process together with the effect of treatment with a nonsteroid anti-inflammatory agent on these trace elements concentrations. In the present study, we used 92 guinea pigs, 12 of which constituted the control group; the remaining 80 were the experimental group. To start with, proquazone (as anti-inflammatory agent) was administered orally to 40 guinea pigs of the experimental group at 20-mg/kg doses 2 h before the surgery. Throughout the experimental period, the above dose was administered to the animals twice a day. We produced inflammation in all animals of the experimental group by using carrageenan (inflammatory agent) dropped into mandibular surgical defects. Serum concentrations of zinc and copper were determined by atomic absorption spectrophotometry in both groups at the 6th, 48th, 120th, 168th, and 240th h. The serum zinc concentrations of the carrageenan-administered group decreased significantly (p<0.01). When comparing the serum zinc concentrations of the carrageenan plus proquazone-administered group with those of control group, the decrease (p<0.05) at the 6th, 48th, and 120th h were statistically significant. When the copper serum concentrations of the carrageenan-administered group were compared with those of the control group, at the 48th, 120th, and 168th h, a statistically significant increase (p<0.01) was observed. However, there was no significant change in the carrageenan plus proquazone-administered group at the 168th and 240th h. As a result during the acute phase of inflammation, serum zinc concentrations decreased, whereas serum copper concentrations increased. The alterations in zinc concentrations were more rapid than those in copper concentrations, but the administration of proquazone slowed the rate of decrease in serum zinc concentrations. This work was presented at the Fourth International Congress of Pathophysiology, June 29–July 5, 2002, Budapest, Hungary.     

Sexual behavior and pregnancy rate of Bos indicus bulls

To study sexual behavior and pregnancy rate of Zebu bulls, 9 Brahman and 6 Nelore bulls were first examined for libido and serving capacity, semen characteristics and scrotal circumference, a week before being placed, individually, into a group of 16 estrus-syncronized heifers to observe mating activity. Scores for libido (0 to 10) and for serving capacity (based on the number of services per period) were assigned for each bull over a 15-min period. Estrus was synchronized with Norgestomet (3 mg, s.c. implant and 3 mg, i.m.) and estradiol valerate (5 mg, i.m.). The implants remained in place for 10 d, then 40 h after their removal a bull was placed with the heifers. Four Brahman and 6 Nelore bulls were monitored for 2 h while the remaining 5 Brahman bulls were observed for 30 h. Number of services and mounts per bull, the hour at which each event took place, and the identification of the heifers serviced were recorded. Pregnancy was diagnosed by transrectal palpation 50 to 60 d after mating. Mean libido score (+/- SEM) of the 15 bulls was 6.4 +/- 0.5, and mean serving capacity was 0.53 +/- 0.19; both of these measures were correlated with age (r = 0.78, P < 0.01, and r = 0.56, P < 0.05, respectively). In the 2-h trials, the number of mounts was correlated with the libido score (r = 0.73, P < 0.05), and the number of services was correlated with age (r = 0.76, P < 0.05) and with libido and serving capacity score (r = 0.91 and 0.92, P < 0.01). In the 30-h trials, the mean (+/- SEM) number of mounts and of services per bull was 74.4 +/- 21.1 and 14.6 +/- 0.5, respectively. The mount-to-service ratio and percentage of serving efficiency were 5.1 +/- 1.4, and 19.8 +/- 4%, respectively. Libido score was correlated with the mount-to-service ratio (r = -0.86, P < 0.10) and with serving efficiency (r = 0.84, P < 0.10). The percentage of heifers serviced, of those serviced 2 or more times and of those pregnant was 55 +/- 5.3; 47.1 +/- 6.4, and 59.2 +/- 5.8, respectively. Pregnancy rate was not correlated with any trait (P > 0.10). It was concluded that libido and the serving capacity test seem to indicate the mating potential of Zebu bulls over a relatively short period of time (e.g. 30 hours), in which resultant pregnancy rates are comparable to those of European bulls.     

Does the platelet-activating factor affect the antioxidant defense system?

The platelet-activating factor (PAF) is an inflammatory mediator and it may exert some of its effects by reactive oxygen species (ROS). We investigated the effects of PAF and hyperbaric oxygenation (HBO) on copper (Cu) and zinc (Zn) levels in plasma and the intracellular antioxidant enzyme activities of rats. PAF administration caused a decrease in erythrocyte catalase (CAT) and glutathione peroxidase (GPx) activities and in the plasma zinc level. Following PAF administration, exposure to HBO also caused a decrease in erythrocyte GPx activity. These results support the hypothesis that PAF may produce free oxygen radicals and HBO enhances this effect. The enzyme activities of the antioxidant defense system were found to be affected by these oxidative processes. This is likely to be the result of excessive production of ROS or overutilization and/or inhibition of the antioxidant enzymes.     

Kinetic models for the dynamical behavior of polyacrylamide (PAAm)–κ-carrageenan (κC) composite gels

A fluorescence method was employed for studying the drying and swelling of PAAm–κC composite gels, which were formed from acrylamide (AAm) and N, N’- methylenebisacrylamide (BIS) with various κ–carrageenan (κC) contents by free radical crosslinking copolymerization in water. Composite gels were prepared at 80 °C with pyranine (Py) as a fluorescence probe. Scattered light, I_sc, and fluorescence emission intensities, I_em, were monitored during drying and swelling of these gels. The fluorescence intensity of pyranine increased and decreased as drying and swelling time are increased, respectively, for all gel samples. The Stern–Volmer equation combined with moving boundary and Li-Tanaka models were used to explain the behavior of I_em during drying and swelling processes respectively. It is found that the desorption coefficient D_d decreased as κC contents were increased for a given temperature during drying. However, the cooperative diffusion coefficient, D_s presented exactly the opposite case. Conventional gravimetrical and volumetric experiments were also carried out during drying and swelling of PAAm–κC composite gels. It was observed that D_d and D_s values measured with the fluorescence method were found to be much larger than they were measured with the conventional methods.     

The fitness consequences of honesty: Under‐signalers have a survival advantage in song sparrows

How honest or reliable signaling can evolve and be maintained has been a major question in evolutionary biology. The question is especially puzzling for a particular class of signals used in aggressive interactions: threat signals. Here, we report a study on song sparrows (Melospiza melodia) in which we assayed males with playbacks on their territories to quantify their aggressiveness (flights and close proximity) and aggressive signaling levels (rates of soft song, a close‐range signal reliably predicting attack) and asked whether these traits affect individuals’ survival on territory. We found that the effect of aggressive signaling via soft song interacted with aggressive behaviors such that there was a negative correlational selection: among males with low aggression, those males that signaled at higher levels (over‐signalers) had higher survival whereas among males with high aggression those that signaled at low levels (under‐signalers) survived longer. In other words, males that deviate from reliable signaling have a survival advantage. These results, along with previous research that suggested most of the deviation from reliable signaling in this system is in the form of under‐signaling (high‐aggression males signaling at low levels) pose a puzzle for future research on how this reliable signaling system is maintained.     

Brain mast cells and therapeutic potential of vasoactive intestinal peptide in a Parkinson's disease model in rats: brain microdialysis, behavior, and microscopy

In the present study, the effect of systemically administered vasoactive intestinal peptide (VIP) (25 ng/kg i.p.) was investigated on drug-induced rotational behavior, extra-cellular dopamine levels and histology of corpus striatum in a 6-hydroxydopamine (6-OHDA)-induced rat model of Parkinson's disease. After 15 days of 6-OHDA lesion, apomorphine-induced (0.05 mg/kg s.c.) rotational behavior of the animals significantly increased and extra-cellular dopamine levels of corpus striatum were significantly reduced. VIP reversed the rotational deficits but did not alter the decrease in striatal dopamine levels. On the other hand, histological data indicate that VIP significantly reduced neuronal death and demyelination. Electron microscopic appearance of mast cells showed ultra-structural variety between VIP-treated and 6-OHDA lesioned groups. VIP activates mast cells without any evidence of typical exocytosis, and possibly mast cells could participate in neuroprotection. Our results suggest that systemically administered VIP can attenuate the motor response changes, neuronal cell death, and myelin sheet loss characteristically associated with 12 microg 6-OHDA administration into the rat striatum. Brain mast cells seem to participate in neuronal protection. Possibly, protective cues could be produced by brain mast cells.