Combined effects of cadmium and nickel on testicular xenobiotic metabolizing enzymes in rats

When male rats were given a single dose of cadmium (Cd) (3.58 mg CdCl₂·H₂O/kg, ip) 72 hr prior to sacrifice, the testicular 7-ethoxyresorufin O-deethylase (EROD) and glutathione S-transferase (GST) activities toward the substrates 1-chloro-2,4-dinitrobenzene (CDNB), 1,2-dichloro-4-nitrobenzene (DCNB), ethacrynic acid (EAA), 1,2-epoxy-3-(p-nitrophenoxy)-propane (EPNP), and cumene hydroperoxide (CHPx) decreased significantly as compared to controls. Cd also inhibited reduced glutathione (GSH) level while increasing the lipid peroxidation (LP) level significantly. When the animals were given a single dose of nickel (Ni) (59.5 mg NiCl₂·6H₂O/kg, ip) 16 hr prior to sacrifice, significant decreases were observed in EROD and GST activities toward CDNB, EAA, EPNP, and CHPx, and GSH level. No significant alterations were noted in DCNB GST activity and LP level by Ni. For the combined treatment, rats received the single dose of Ni 56 hr after the single dose of Cd and were killed 16 hr later. In these animals, lesser depressions were observed on EROD activity and LP level than those of Cd alone. The combination of metals significantly inhibited GST activities and GSH level but not to a greater degree than noted by Cd or Ni alone. Plasma testosterone levels of Cd-, Ni-, and combination-treated rats decreased significantly compared to controls. The strongest depression was achieved by Cd alone. Cd, both alone and in combination with Ni, increased the tissue Ni uptake significantly. Ni, however, did not produce such an effect on the tissue uptake of Cd in either case. Cd treatment caused interstitial edema and coagulation necrosis in seminiferous tubules and also caused fibrinoidal necrosis in vascular endothelium. Ni treatment did not produce any pathological testicular alterations compared to controls. Combined treatment produced fewer pathological alterations (i.e., only interstitial edema) than that of Cd treatment. These results reveal that the combination of Cd and Ni does not have a synergistic effect on testicular xenobiotic metabolizing enzymes, and in contrast, Ni has an ameliorating effect on pathological disturbances caused by Cd alone in the rat testis.     

Food webs in sub-Antarctic lakes: a stable isotope approach

In order to improve the understanding of food-web interactions in sub-Antarctic freshwater systems, we complemented earlier experimental studies with analyses of differences in stable isotopes (¹⁵N and ¹³C) among organisms in two lakes with contrasting productivity. The distribution of the stable isotopes showed that the small copepod Boeckella michaelseni feeds mainly on pelagic POM (particulate organic material), whereas the larger copepod species B. poppei also feeds on benthic algae. Furthermore, the predatory copepod Parabroteas sarsi seems to mainly feed on B. michaelseni, but also on B. poppei and the benthic cladoceran, Alona weineckii. Moreover, stable-isotope data suggest that the diving beetle, Lancetes angusticollis, is not only feeding on B. poppei as indicated from experimental studies, but also on the benthic cladoceran A. weineckii. Although the food webs of the two lakes are very similar, they show considerable differences in the distribution of stable isotopes. We conclude that monitoring, experiments and stable-isotope analysis in combination give a reasonably clear picture of sub-Antarctic freshwater food webs.     

Hair-bearing submental artery island flap for reconstruction of mustache and beard

Loss of mustache and beard in the adult male caused by severe burn, trauma, or tumor resection may cause cosmetic and psychological problems for these patients. Reconstruction of the elements of the face presents difficult and often daunting problems for plastic surgeons. The tissue that will be used for this purpose should have the same characteristics as the facial area, consisting of thin, pliable, hair-bearing tissue with a good color match. There is a very limited amount of donor area that has these characteristics. A hair-bearing submental island flap was used successfully for mustache and beard reconstruction in 11 male patients during the last 5 years. The scar was on the mentum in four cases, right cheek in two cases, right half of the upper lip in two cases, left cheek in one case, left half of the upper lip in one case, and both sides of the upper lip in one case. The submental island flap is supplied by the submental artery, a branch of the facial artery. The maximum flap size was 13 x 6 cm and the minimum size was 6 x 3 cm (average, 10 x 4 cm) in this series. Direct closure was achieved at all donor sites. Patients were followed up for 6 months to 5 years. No major complication was noted other than one case of temporary palsy of the marginal mandibular branch of the facial nerve. The mean postoperative stay was 7 days. Color and texture match were good. Hair growth on the flap was normal, and characteristics of the hair were the same as the intact side of the face in all patients. The submental island flap is safe, rapid, and simple to raise and leaves a well-hidden donor-site scar. The authors believe that the submental artery island flap surpasses the other flaps in reconstruction of the mustache and beard in male patients. Application of the technique and results are discussed in this article.     

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.     

Reconstruction of the weight-bearing surface of the foot with nonneurosensory free flaps

Neurotized fasciocutaneous flaps and split-skin grafted muscle flaps are the most frequently used free flap alternatives for the reconstruction of weight-bearing surfaces of the foot. An objective comparison of the innate characteristics of these two flap types, with respect to long-term stability, has not been possible because sensory reinnervation in the fasciocutaneous flaps has been a confounding factor. This study compares nonsensate fasciocutaneous flaps (n = 9) with nonsensate split-skin grafted muscle flaps (n = 11), with mean follow-up periods of 34.3 and 31.3 months, respectively. Patients completed a form that included questions regarding degree of pain at the operative site, presence of ulcers, ability to wear normal shoes, employment status, and time spent standing on foot. Touch and deep sensation were evaluated with Semmes-Weinstein and vibration tests, respectively. Significantly less pain and less ulceration (p < 0.05) were observed in the fasciocutaneous group. Semmes-Weinstein monofilament tests revealed poorer results with split-skin grafted muscle flaps, compared with fasciocutaneous flaps. These results indicate that even if the sensory protection of fasciocutaneous flaps is not considered, these flaps have superior properties, compared with split-skin grafted muscle flaps.     

Long-term history of land-use and vegetation at Ire,an agriculturally marginal area in Blekinge,south Sweden

Pollen records from a small lake and a small peatland at Ire in northern Blekinge, Sweden, reveal that until a.d. 300 there was a mixed deciduous type of woodland dominated by Quercus, Tilia and Corylus, with Betula, Pinus, Populus, Fraxinus, Ulmus and Acer as important constituents. The first, but weak, signs of human influence on the vegetation are detected around 2300 b.c. At this time, the area was probably used for woodland grazing. The regional expansion of Fagus occurred around 100 b.c.–a.d. 200, and later, at about a.d. 500, woods dominated by Fagus were common in the area. Around a.d. 600–700 an isolated farmstead may have been established in the area, as single pollen grains of Secale (rye) were found. This farmstead may represent the first permanent settlement in the area. A more widespread opening of the vegetation occurred around a.d. 1000, probably as an effect of a more pronounced use of the area, and an expansion of settlements in the region. The openness of the area seems to have peaked around a.d. 1400–1800, and during this period the vegetation was highly fragmented with small stands of woodland, intensively grazed pastures, and arable fields where Secale and Triticum were mainly cultivated. Around a.d. 1600 Fagus pollen percentages sharply decrease, most probably caused by a deliberate and selective felling of beech trees for the production of potash, which consumed enormous amounts of wood. Picea seems to have been established around a.d. 1600, but it did not become a regional dominant until the first part of the 20th century, when land use decreased and it became favoured by forestry.