Influence of experimental type 1 diabetes on the pulmonary effects of diesel exhaust particles in mice

Epidemiologically, exposure to particulate air pollution is associated with increases in morbidity and mortality, and diabetics are especially vulnerable to effects of particles. This study was carried out to determine the respiratory effect of diesel exhaust particles (DEP; 0.4 mg/kg) on mice rendered diabetic by the injection of streptozotocin or vehicle (control). Four weeks following induction of diabetes, the animals were intratracheally instilled (i.t.) with DEP (0.4 mg/kg) or saline. 24 h later, the measurement of airway reactivity to methacholine in vivo by a forced oscillation technique showed a significant and dose-dependent increase in airway resistance in non-diabetic mice exposed to DEP versus non-diabetic mice exposed to saline. Similarly, the airway resistance was significantly increased in diabetic mice exposed to DEP versus diabetic mice exposed to saline. Nevertheless, there was no difference in the airway resistance between diabetic and non-diabetic mice after i.t. administration of DEP. Following DEP administration there were neutrophil polymorphs infiltration of pulmonary interalveolar septae and the alveolar spaces with many macrophages containing DEP in both diabetic and non-diabetic mice. Interestingly, apoptotic cells were only found in the examined lung sections from diabetic mice exposed to DEP. Total proteins and albumin concentrations in bronchoalveolar lavage (BAL) fluid, markers for increase of epithelial permeability, were significantly increased in diabetic mice exposed to DEP compared to saline-treated diabetic and DEP-treated non diabetic mice. Superoxide dismutase activity and reduced glutathione concentration in BAL were significantly decreased in diabetic mice exposed to DEP compared to saline-treated diabetic and DEP-treated non diabetic mice. Moreover, tumor necrosis factor α (TNFα) concentrations were significantly increased in diabetic mice exposed to DEP compared to saline-treated diabetic and DEP-treated non diabetic mice. We conclude that, at the dose and time point investigated, DEP equally increased airway resistance and caused infiltration of inflammatory cells in the lung of both diabetic and non-diabetic mice. However, the occurrence of oxidative stress, the presence lung apoptotic cells and the increase of total proteins, albumin and TNFα in BAL fluid were only seen in DEP-exposed diabetic mice suggesting an increased respiratory susceptibility to particulate air pollution.     

Recovery of anaerobic bacteria from pediatric patients. A one-year experience.

During 1975, 115 speciments from the soft tissues, body fluids, and purulent sites in 105 pediatric ward and nursery patients were submitted to the clinical laboratory for anaerobic study, and 75% of the cultures were positive. In most instance specimens were collected in anaerobic transport tubes containing peptone yeast extract and glucose. In the laboratory, samples were processed by the anaerobic holding jar method. Nineteen different anaerobic organisms were isolated; the average number of species per specimen was 1.8 Bacteroides sp were the most common isolates (45 strains). Other isolates included 44 anaerobic cocci (15 of which were Peptostreptococcus sp), 22 Propionibacterium sp, ten Fusobacterium sp, nine Clostridium sp, eight Veillonella sp, six Bifidobacterium sp, and four Eubacterium sp. The main sources of anaerobic isolates included 52 gastric aspirates, 46 soft tissue sites, 14 blood specimens, 12 CSF samples, and 12 samples from the external ear canals. Forty-one (43%) of the 86 specimens that contained anaerobic bacteria also had aerobic organisms present.     

Melatonin-secreting pineal gland: a novel tissue source for neural transplantation therapy in stroke

Chronic systemic melatonin treatment attenuates abnormalities produced by occlusion of middle cerebral artery (MCA) in adult rats. Because the pineal gland secretes high levels of melatonin, we examined in the present study whether transplantation of pineal gland exerted similar protective effects in MCA-occluded adult rats. Animals underwent same-day MCA occlusion and either intrastriatal transplantation of pineal gland (harvested from 2-month-old rats) or vehicle infusion. Behavioral tests (from day of surgery to 3 days posttransplantation) revealed that transplanted stroke rats displayed significantly less motor asymmetrical behaviors than vehicle-infused stroke rats. Histological analysis at 3 days posttransplantation revealed that transplanted stroke rats had significantly smaller cerebral infarction than vehicle-infused rats. Additional experiments showed that pinealectomy affected transplantation outcome, in that transplantation of pineal gland only protected against stroke-induced deficits in stroke animals with intact pineal gland, but not in pinealectomized stroke rats. Interestingly, nonpinealectomized vehicle-infused stroke rats, as well as pinealectomized transplanted stroke rats, had significantly lower melatonin levels in the cerebrospinal fluid than nonpinealectomized transplanted stroke rats. We conclude that intracerebral transplantation of pineal gland, in the presence of host intact pineal gland, protected against stroke, possibly through secretion of melatonin.     

Effects of Zn and Ti Nanoparticles on the Survival and Growth of <Emphasis Type="Italic">Sclerophrys arabica</Emphasis> Tadpoles in a Two Level Trophic System

Under natural conditions pollutants rarely affect only a single trophic level. This study investigated the effects of titanium dioxide (Ti-NPs) and zinc oxide (Zn-NPs) nanoparticles on survival and growth of Sclerophrys arabica tadpoles exposed directly in water, indirectly through their food source (decomposing leaves), or a combination of both. Zn-NPs did not cause significant mortality. The LC50 for tadpoles exposed to Ti-NPs directly was 74.9 µg/L (95% CI 16.6–338.7 µg/L) and 18.3 µg/L (95% CI 6.5–51.9 µg/L) for tadpoles exposed directly and with pre-treated leaves. Tadpoles fed only pre-exposed food did not show significant mortality. Exposure route also affected growth. On average the tadpoles with the lowest body mass were found in the water-only exposures, followed by the water and leaf treatments. However, the tadpoles with the greatest body mass were in the treatments fed with leaves pretreated with Ti-NPs. This suggests that the NPs made their contents more available to the tadpoles.     

Treatment of post-burn and post-traumatic atrophic scars with fractional CO<Subscript>2</Subscript> laser: experience at a tertiary care centre

Scars are abnormal wound responses in predisposed individuals. They occur after any kind of wound and skin inflammation in predisposed individuals. Despite their benign nature, they can be aesthetically disabling. Although several approaches have been tried in their management, most of them have produced poor results. This study aims to assess the efficacy and safety of fractional CO₂ laser treatment in the management of post-burn and post-traumatic scars. One hundred consecutive patients (77 females and 23 males) affected by post-burn scars as well as post-traumatic atrophic scars were treated with monthly sessions of fractional CO₂ laser treatment. Patient’s response to treatment was assessed clinically as well as improvement of scars by comparing the photographs taken before treatment with those taken 6 months after the last treatment session. Changes in skin texture, surface irregularity and pigmentation were assessed on a quartile grading scale and scored individually from 0 to 4. A mean of the three individual scores was calculated and the response was labelled as ‘excellent’ if the mean score achieved was >?3. A score of 2–3 was labelled as good response while a score below 1 was labelled as ‘poor’ response. A mean of six treatments per scar were required and all patients, followed up for 1 year after the last treatment, had optimum results and no recurrence. Response to treatment was excellent in 53.75%, good in 16.25% patients, and poor in 30% patients. Fractional CO₂ laser gives a very good result in the management of patients with post-burn scars as well as post-traumatic scars with minimal adverse effects.     

Parents' anxieties about the risk of HIV/AIDS for their Deaf and hard of hearing adolescents in South Africa: a qualitative study

Adolescents who are Deaf or hard of hearing may be vulnerable to HIV/AIDS. Adolescents' open communication with parents encourages positive sexuality. The relationship between the Deaf adolescent and their parent could be obstructed by communication difficulties. This article explores parents' anxieties about HIV risk. We interviewed nine parents of Deaf adolescents in South Africa. We explored their fears of the risk of HIV/AIDS for their children. Participants believed that their children were at risk of HIV infection. Although they did communicate with their children about sexuality and HIV/AIDS, some experienced communication difficulties. Communicative relationships between these adolescents and their parents should be encouraged.     

The effect of sildenafil on cisplatin nephrotoxicity in rats

Sildenafil, the first drug for erectile dysfunction, has cardiopulmonary protective actions. A recent study has reported that sildenafil given intraperitoneally (i.p.) attenuated cisplatin (CP)-induced nephrotoxicity. Here, we evaluated whether sildenafil, given by two different routes and at two different doses, can attenuate CP-induced nephrotoxicity and would also affect renal haemodynamics in CP-treated rats. Six groups of rats were treated with saline (controls), CP [5 mg/kg, intraperitoneally (i.p.) once], sildenafil (0.4 mg/kg/day, i.p. for 5 days), sildenafil (0.4 mg/kg/day i.p. for 5 days) plus CP (5 mg/kg, i.p., once), sildenafil [10 mg/kg/day, subcutaneous (s.c.) for 5 days] or sildenafil (10 mg/kg/day, s.c. for 5 days) plus CP (5 mg/kg, i.p. once). Five days after the end of the treatments, urine was collected from all rats, which were then anaesthetized for blood pressure and renal blood flow monitoring. This was followed by intravenous (i.v.) injection of norepinephrine for the measurement of renal vasoconstrictor responses. Thereafter, blood and kidneys were collected for measurement of several biochemical, functional and structural parameters. CP reduced body-weight and renal blood flow but did not affect norepinephrine-induced renal vasoconstriction. It increased the plasma concentrations of urea and creatinine, and reduced creatinine clearance. CP caused extensive renal tubular necrosis, increased urine volume and N-acetyl-β-D-glucosaminidase activity. When sildenafil (0.4 mg/kg/day, i.p. for 5 days) was combined with cisplatin, there was a dramatic improvement in renal histopathology, reduction in N-acetyl-β-D-glucosaminidase and increase in renal blood flow. However, sildenafil (10 mg/kg/day, s.c. for 5 days) did not affect CP nephrotoxicity, suggesting the importance of dose and route selection of sildenafil as a nephroprotectant.