Acid burns from personal assault in Uganda

Acid burns from assault represent a substantial and neglected proportion of burn injuries in the developing world. A retrospective chart review was conducted to assess the frequency of acid burns in relation to total burns requiring admission in Kampala, Uganda. Seventeen percent of the adult burns admitted at New Mulago hospital over an 18-month period resulted from acid assault. Patients had a mean age of 33.1 years, with a male to female ratio of 1.1:1. The average extent of injury was 14.1% total body surface area (TBSA), commonly involving the face (86.7%), head and neck (66.7%), upper limbs (60.0%) and chest (53.3%). Thirty-three percent of patients suffered partial or complete blindness. Mean length of stay in hospital was 49.5 days and all patients survived. Patterns of assault followed two common trends: attacks during robberies (46.7%), and attacks associated with domestic disputes (33.3%). The Ugandan pattern is contrasted with patterns reported from Bangladesh, Cambodia and Jamaica with a view to understanding the social context underlying such assaults. Prevention of these hideous injuries will require further understanding of their underlying social and cultural determinants. Serious questions remain whether public education programs will reduce the incidence of acid assault or increase it by giving potential assailants an idea they did not have before.

Differential patterns of histone methylation and acetylation distinguish active and repressed alleles at X-linked genes

In female mammals, one of the two X chromosomes is inactivated to compensate for the difference in dosage of X-linked genes between males and females. X inactivation involves sequential alterations to the chromatin that ultimately lead to the transcriptional repression of genes on the X chromosome. Here, histone methylation and acetylation along X-linked genes are investigated by chromatin immunoprecipitation (ChIP) of adult fibroblast cell lines. At PGK1 and HPRT, chromatin on the active X chromosome reveals H3 lysine 4 methylation and acetylation of histones H3 and H4. These modifications are absent on the repressed allele, which is marked by H3 lysine 9 methylation. On the expressed allele of XIST (on the inactive X chromosome), we found that H3 acetylation is confined to the promoter, whereas H3 lysine 4 methylation and H4 acetylation are present along the entire gene. On the repressed XIST allele, in contrast, the promoter and gene exhibit H3 lysine 9 methylation. At only 1.5 kb upstream of the XIST gene, chromatin on the inactive X chromosome has strongly reduced levels of H4 acetylation and is marked by both H3 lysine 9 and H3 lysine 4 methylation. These data demonstrate that patterns of histone methylation and acetylation are distinct along and upstream of XIST and suggest that the inactive X chromatin configuration occurs at a region close to the 5' end of the gene.

204THE PRODUCTION OF INTRACYTOPLASMIC SPERM INJECTION LION (PANTHERA LEO) EMBYROS USING SPERMATOZOA COLLECTED BY PERCUTANEOUS EPIDIDYMAL SPERM ASPIRATION FROM VASECTOMIZED MALES

Contraception and/or sterilization methods have become an essential component of many captive animal management programs. Sterilization techniques are considered to be the last resort if a viable contraceptive cannot be attained and are generally not considered reversible. The African lion (Panthera leo) is one species in which sterilization techniques have been routinely applied. The objective of this study was to develop and evaluate a method for the collection of spermatozoa from male lions that have been previously rendered sterile by vasectomy. Percutaneous epididymal sperm aspiration (PESA) is a technique in which spermatozoa are aspirated from the epididymis and no surgical incision is required. In the present study, two lions (12 and 19 yrs old) were anesthetized and PESA was attempted. A 21-gauge needle attached to a 10-mL syringe (Norm-Ject) filled with 2–3mL of Tyrodes HEPES medium was gently inserted into the head of the epididymis and aspirated gently until spermatozoa were noted. Spermatozoa were visually assessed for motility (grade 1–5; 1=few motile sperm to 5=all motile), sperm concentrations were determined and then the sperm were cryopreserved. The total sperm concentration collected from the older (19yr) male was lower than that obtained from the younger (12yr) lion (0.08×106sperm/mL v. 65.5×106sperm/mL, respectively). Furthermore, more motile spermatozoa (grade 3) were collected from the younger individual compared to the older male (grade 1). Sperm samples from the 12-yr-old lion were frozen by multi-step addition of TEST yolk buffer+glycerol. Lionesses (n=3) were subjected to laparoscopic oocyte retrieval after gonadotropin treatment. A total of 38 oocytes were retrieved and 74% (28/38) were mature as determined by extrusion of the first polar body. Mature oocytes were subjected to ICSI using frozen-thawed spermatozoa obtained by PESA. More than 60% (17/28) of the injected oocytes cleaved and 100% (17/17) reached the morula stage by Day 5 or 6 of IVC. Embryos were cryopreserved and were subsequently transferred (n=15) into one lioness. We have demonstrated that it is possible to collect viable spermatozoa from sterile male lions using the PESA technique. Spermatozoa collected were motile and could be cryopreserved and functional for assisted reproductive techniques. This technique could be applied to other infertile or sterile males whose genetic background would benefit a current conservation program.

An evaluation of internet sites for burn scar management

Patients rely on the Internet for medical information. It is difficult to discern which resources are accurate or appropriate for patients. The purpose of this study was to develop a quality-assessment tool for health Internet Web sites and to apply this tool to assess the quality of burn scar management information on the Internet. Between September and December 2001, we prospectively evaluated all Web sites on the Internet search engine Yahoo! containing the headings "burn scar management," "burn scar healing," "burn scar treatment," and "burn scar therapy." The quality of each Web site's medical information was evaluated using our scoring system consisting of the following two components: quality and technical characteristics. The total score for each Web site was converted to a percent grade (eg, > or =80% = excellent, 70 to 79% = very good, 60 to 69% = good, 50 to 59% = fair, and <50% = poor). The Web sites were grouped into three categories: commercial (for profit), academic (university, hospital), and organizational (nonprofit). Of 88 Web sites evaluated, the majority 68 (77%) were commercial, 7 (8%) academic, and 13 (15%) organizational. Burn scar management information on the Internet was poor in the majority (79%) of commercial Web sites and was excellent, very good, or good in the majority of academic (86%) and organizational (77%) Web sites. Using our health information evaluation, we found that the majority of burn scar management information on the internet (77%) was of fair or poor quality. Academic and organizational Web sites had the best quality of burn scar management information. Additional testing of the developed tool will be needed to analyze the reproducibility of the results and their applicability in other medical domains.

Effects of meiosis-inhibiting agents and equine chorionic gonadotropin on nuclear maturation of canine oocytes

Experiments were conducted to determine the effects of meiosis-inhibiting-agents and gonadotropins on nuclear maturation of canine oocytes. The culture medium was TCM199 + 10 ng/ml epidermal growth factor supplemented with 25 microM beta-mercaptoethanol, 0.25 mM pyruvate, and 1.0 mM L-glutamine (Basal TCM). Initially, oocytes were cultured in Basal TCM alone or in Basal TCM + dibutylryl cyclic adenosine monophosphate (0.5, 1, 5, or 10 mM dbcAMP) for 24 hr. Dibutylryl cAMP inhibited resumption of meiosis in a dose-dependent manner; 60% of oocytes remained at the germinal vesicle (GV) stage after being cultured for 24 hr in 5 mM dbcAMP. The meiosis-inhibitory effect of dbcAMP appeared to be reversible, as the oocytes resumed meiosis and completed nuclear maturation after being cultured for an additional 48 hr in its absence. Oocytes were then cultured in Basal TCM alone or in Basal TCM + roscovitine (12.5, 25, or 50 microM) for 24 hr. Although approximately 60% of oocytes cultured in 25 microM roscovitine remained at the GV stage, this percentage was not significantly different from the 48% that also remained at the GV stage when cultured in its absence. Oocytes were cultured in Basal TCM + 25 microM roscovitine for 17 hr, exposed briefly to equine chorionic gonadotropin (eCG), and then cultured in Basal TCM for 48 hr. Short exposure of oocytes to eCG was beneficial, as it significantly increased the proportion of oocytes developing beyond germinal vesicle breakdown (P < 0.05) with approximately 20-30% of these were metaphase I (MI) oocytes. Study of the kinetics of nuclear maturation demonstrated that large numbers of oocytes remained at MI even after being cultured for 52 hr following brief exposure to eCG. This study showed that in vitro maturation of canine oocytes can be somewhat improved by short exposure of oocytes to eCG. However, further studies are still required to derive effective methods to mature canine oocytes in vitro.

A survey of risk factors for burns in the elderly and prevention strategies

Elderly burn patients suffer from greater morbidity and mortality than younger patients with similar burn extents. The purpose of this study was to identify risk factors for burn injuries in the elderly to develop an effective preventive program. A cross-sectional survey was conducted among 20 elderly (> or =65 years of age) burn survivors on the circumstances surrounding their burn injury and on burn prevention. A control group of 20 nonburned elderly completed a similar survey only on burn prevention. The majority of burned subjects believed that their injury was preventable (85%). The home was the commonest location for burn injury (70%), and scalds (50%) and flame burns (25%) were the most common etiologies. Most subjects felt that a burn prevention program would be useful (95%) and television, news, and posters were the preferred sources of prevention information. Compared with the burn group, the control group had more risk factors for burn injury. However, the control group also took more active preventive measures. Burn prevention campaigns for elderly should focus on reducing flame and scald burns that occur in the home, preferably using television, news, and poster media.

Characterization of paint samples used in drinking water reservoirs: identification of endocrine disruptor compounds

Several migration tests are performed from various epoxy paint samples that, according to the regulation, can be used in food reservoirs such as drinking water reservoirs. The level of the organic compounds capable of producing migrations to water with special attention to endocrine disruptor compounds (EDCs) are identified and estimated by closed loop-stripping analysis (CLSA) and liquid-liquid extraction (LLE) methods coupled with gas chromatography (GC)-mass spectrometry (MS). Bisphenol A, a strong endocrine disruptor, is found in all migration experiments. Its concentration level reaches between 0.02 and 0.03 mg/cm2. The higher concentration corresponds with benzylic alcohol, which is used as a solvent and curing agent in epoxy paint. Other EDCs identified in the migration tests are phthalates, 4-nonylphenol, and t-butylphenol. The main non-EDCs identified are solvents, antioxidants, and rubber-like compounds. No great differences are found in the use of metallic plates or concrete slabs for migration experiments; only additional compounds related with the pretreatment of the concrete wall have been identified, too. In the study of a drinking water sample the same organic compounds identified in the migration test is not seen. This is probably because of the dynamic situation in a drinking water reservoir. Finally, a GC profile of a direct epoxy paint analysis is shown. The main peak identified is bisphenol A diglycidyl ether, monomer, and an active principle of the polymerization of epoxy resins based on bisphenol A. In addition, we report the recoveries of a selected group of EDCs using CLSA and LLE methods coupled with GC-MS.

An initial experience with telemedicine in follow-up burn care

Following care in a burn unit, regular outpatient visits with burn specialists are required. The practical use of telemedicine in this context is unknown. The objective of this study was to evaluate patient and physician satisfaction with teleconsultations in follow-up burn care and to assess the costs and benefits of these teleconsultations. Fourteen teleconsultations were conducted between a burn physician and a patient at a remote site. Patients and the physician completed evaluation questionnaires for each teleconsultation. Time-related and financial costs of the consultation service were also determined. Patients were very satisfied with their teleconsultations and found them more economical and time efficient than in-person visits. The consulting physician felt teleconsultations were as satisfactory as clinic visits for the purposes of diagnosis and burn management. Our results support the ongoing use of telemedicine in the follow-up care of burn patients.

The GTPase Rac-1 controls cell fate in the thymus by diverting thymocytes from positive to negative selection

The positive selection of CD4 or CD8 single-positive mature peripheral T lymphocytes and the deletion of self-reactive cells are crucial for central tolerance in the peripheral immune system. Previously, the guanine nucleotide binding protein Rac-1 has been shown to control pre-T cell development. The present report now describes the actions of Rac-1 in thymocyte selection. The study reveals that this molecule has the striking and unique ability to efficiently divert cells from positive selection into a pathway of negative selection and deletion. The ability of Rac-1 to switch thymocytes from a destiny of positive to negative selection identifies this molecule as a critical regulator of the developmental processes in T cells that are essential for immune homeostasis.

Early clinical experience with high-frequency oscillatory ventilation for ARDS in adult burn patients

Lung protective ventilation strategies are recommended in acute respiratory distress syndrome to avoid ventilator associated lung injury, a recently characterized complication of mechanical ventilation. High-frequency oscillatory ventilation (HFOV) is an unconventional ventilation strategy which may achieve this goal. We reviewed our experience with HFOV in six severely burned patients with acute respiratory distress syndrome. The mean age (+/- SD) of the patients was 34 +/- 13 years, and the mean TBSA burn was 52 +/- 10%, with a mean full-thickness injury of 49 +/- 12%. HFOV was initiated as "rescue therapy" in three patients with oxygenation failure (mean PaO2/FIO2 ratio of 71 +/- 8 and mean oxygenation index [OI] of 42 +/- 3) that was unresponsive to conventional ventilation (mean FIO2, 1.0 +/- 0; mean positive end expiratory pressure, 14.8 +/- 2.8 cm H2O; and mean inhaled nitric oxide, 20 +/- 0 ppm). In the other three cases, HFOV was initiated "prophylactically" as a lung protective ventilation strategy in an attempt to prevent further respiratory deterioration. All six patients showed a rapid and substantial improvement in oxygenation after initiation of HFOV, with significant improvements in the PaO2/FIO2 and OI by 12 hours (P = 0.02). In four patients HFOV was also used during anesthesia and surgery, where a total of 10 procedures involving a mean excision and closure of 15 +/- 7% TBSA burns was performed. Five of the six patients died, but none died because of oxygenation failure. In three patients death resulted from sepsis and multiple organ dysfunction syndrome; their mean PaO2/FIO2 was 107 +/- 31 and their mean OI was 30 +/- 11 immediately before death. Two patients with multiple organ dysfunction syndrome died after withdrawal of life support; their mean PaO2/FIO2 and OI were 178 +/- 31 and 18 +/- 2 respectively, at the time of this decision. Although HFOV had no impact on mortality, it played a useful role in the supportive management of burn patients with severe oxygenation failure unresponsive to conventional ventilation. Importantly, HFOV allowed surgery to proceed in patients who may have otherwise been too unstable to go to the operating room. As far as we are aware, this is the first report of the use of intraoperative HFOV in burn patients.

The use of silver coated dressings on donor site wounds: a prospective, controlled matched pair study

Acticoat, a new silver-coated dressing, produces a moist healing environment along with the sustained release of ionic silver for improved microbial control. These properties suggest that Acticoat might be a useful donor site dressing. However, there are no human studies which assess Acticoat for this use. The purpose of this study was to compare the healing of human skin graft donor sites dressed with Acticoat, to the healing of those dressed with Allevyn, an occlusive moist-healing environment material, which is our standard donor site dressing. In burn patients who had undergone burn excision and grafting, identical side-by-side split thickness donor site wound pairs were dressed with Allevyn and Acticoat. Re-epithelialization was directly assessed daily by a single observer from post-operative day 6 onward, and by four independent observers who rated the extent of re-epithelialization by viewing standardized digital images of the wounds that had been obtained on post-operative days 6, 8, 10,and 12. Donor sites were swabbed for bacterial culture on days 3, 6, and 9. Subsequently, each study donor site scar was rated by a blinded observer using the Vancouver Scar Scale at 1, 2, and 3 months. Sixteen paired sites in 15 patients (3 female, 12 male) were studied. Donor sites dressed with Allevyn were >90% re-epithelialized at a mean of 9.1+/-1.6 days while donor sites dressed with Acticoat required a mean of 14.5+/-6.7 days to achieve >90% re-epithelialization (P=0.004). The Allevyn sites had significantly greater estimated re-epithelialization at days 6, 8, 10 and 12 than the Acticoat sites based on the observations of the digital images. There were no significant differences in the incidence of positive bacterial cultures with either dressing at days 3, 6, and 9. Donor sites dressed with Acticoat had significantly worse scars at 1 and 2 months but this difference resolved by 3 months. Our findings do not support the use of Acticoat as a skin graft donor site dressing.

Characterization of the secreted MPT53 antigen of Mycobacterium tuberculosis

MPT53 is a secreted protein of Mycobacterium tuberculosis. Southern transfer and hybridization showed mpt53 to be conserved in the M. tuberculosis complex and to have homology with DNA from Mycobacterium avium and other nontuberculous mycobacteria. However, anti-MPT53 polyclonal antibodies detected no antigen in the culture filtrates of M. avium and other nontuberculous mycobacteria. MPT53 of M. tuberculosis induced strong, tuberculosis-specific antibody responses in guinea pigs but induced no delayed-type hypersensitivity. Involvement in immune responses during human tuberculosis was very modest.

Prevalence, detection and treatment of anxiety, depression, and delirium in the adult critical care unit

This study assesses the levels of depression, anxiety, and delirium during admission to three adult critical care units (CCU) and the performance of CCU staff with respect to detection and treatment. During a 1-month period, 96 consecutive patients were evaluated on the first day of admission by an independent rater, using the Hospital Anxiety Depression Scale and the Confusional Assessment Method. Frequency of alcohol use and demographic data were recorded. CCU teams rarely made diagnoses of anxiety, depression, or delirium. On at least one screening test, 29.2% of patients were positive. Delirium was present in 7.3%, depression in 13.7%, anxiety in 24%, and possible problem drinking in 37.9%. Although some form of psychiatric treatment was offered to 58%, there was low agreement between psychiatric diagnoses made by the independent rater and the diagnoses made and treatments used by CCU staff. This suggests that the CCU staff are using psychotropic medications without any clear documentation and perhaps clear understanding of the psychiatric diagnoses they are treating. In summary, we found high rates of psychiatric disorders in adult CCU patients but low rates of detection and only moderate rates of treatment by CCU staff.

Flow cytometry of cell proliferation through the incorporation of bromodeoxyuridine as an index of growth rate in the water flea, Daphnia magna (Crustacea, Cladocera)

BACKGROUND

In this paper, we used a small crustacean as a model to develop a method for quantifying growth rates through the measurement of a cell proliferation marker. This was done in order to study the feasibility of this assay for estimating zooplankton production in the ocean. Flow cytometry immunodetection of bromodeoxyuridine (BrdU) was performed to detect and quantify the cycling nuclei of Daphnia magna.

METHODS

A combination of mechanical dissociation and cell enucleation procedures proved to be the most convenient method for preparing nuclear suspensions from whole organisms. Up to three populations of nuclei with different ploidy were observed. The relative abundance of these nuclear populations changed with the size of the flea.

RESULTS

The staining technique has been optimized. The time and concentration for the maximum detection of BrdU-labeled nuclei were 3 h at 300 microM BrdU. Whole organisms can be frozen (-20 degrees C) after incubation with no changes in the final results. The method was used in different physiological conditions under controlled food and temperature in order to test the inverse relationship between physiological rates and size of organisms at several developmental stages. The quantification of BrdU-labeled nuclei in 1-6 day-old larvae showed the highest labeling index, with a mean of 95 +/- 1% (n = 22). In contrast, young animals (0.8-1.2 mm) had 25 +/- 4% (n =16, P < 0.001) and adults (>1.4mm) had 14 +/- 3% (n = 4, P < 0.001). The results obtained show an expected tendency, suggesting that a direct relationship exists between the labeling index and the instantaneous growth rate.

CONCLUSIONS

Certain features of our method, such as the short times required for labeling and the possibility of preserving the samples during field experiments and under different conditions (including natural concentrations and types of food), are advantageous to the study of processes governing energy fluxes in pelagic ecosystems.

Complications of outpatient parenteral antibiotic therapy in childhood

Complications in children receiving outpatient parenteral antibiotic therapy were reviewed. Catheter-associated complications and/or adverse drug reactions occurred in 50% of courses. Most complications were minor, and almost all infections were successfully treated. Even with early discontinuation of parenteral antibiotics because of adverse drug reactions in 24% of the courses, the outcome was excellent.

Ca2+ signaling via the neuronal calcium sensor-1 regulates associative learning and memory in C. elegans

On a radial temperature gradient, C. elegans worms migrate, after conditioning with food, toward their cultivation temperature and move along this isotherm. This experience-dependent behavior is called isothermal tracking (IT). Here we show that the neuron-specific calcium sensor-1 (NCS-1) is essential for optimal IT. ncs-1 knockout animals show major defects in IT behavior, although their chemotactic, locomotor, and thermal avoidance behaviors are normal. The knockout phenotype can be rescued by reintroducing wild-type NCS-1 into the AIY interneuron, a key component of the thermotaxis network. A loss-of-function form of NCS-1 incapable of binding calcium does not restore IT, whereas NCS-1 overexpression enhances IT performance levels, accelerates learning (faster acquisition), and produces a memory with slower extinction. Thus, proper calcium signaling via NCS-1 defines a novel pathway essential for associative learning and memory.