Experimental leprosy in the mangabey (Cercocebus atys): necropsy findings

A mangabey monkey (Cercocebus atys) was inoculated intravenously and intracutaneously with acid-fast bacilli (AFB) from a mangabey with spontaneously acquired leprosy. It developed generalized lepromatous leprosy and died 46 months after inoculation. Necropsy revealed severe lepromatous infiltrates in the skin, nasal mucosa, peripheral nerves, and testicles. Internal organs were only minimally involved. The lesions seen at necropsy were very similar to those seen in untreated cases of human lepromatous leprosy. These findings further substantiate the mangabey monkey as a suitable animal model for the study of lepromatous leprosy.     

Thrombolytic therapy for central venous catheter occlusion

Background

Long-term central venous catheters have improved the quality of care for patients with chronic illnesses, but are complicated by obstructions which can result in delay of treatment or catheter removal.

Design and Methods

This paper reviews thrombolytic treatment for catheter obstruction. Literature from Medline searches using the terms “central venous catheter”, “central venous access device” OR “central venous line” associated with the terms “obstruction”, “occlusion” OR “thrombolytic” was reviewed. Efficacy of thrombolytic therapy, central venous catheter clearance rates and time to clearance were assessed.

Results

Alteplase, one of the current therapies, clears 52% of obstructed catheters within 30 min with 86% overall clearance (after 2 doses, when necessary). However, newer medications may have higher efficacy or shorter time to clearance. Reteplase cleared 67–74% within 30–40 min and 95% of catheters overall. Occlusions were resolved in 70 and 83% of patients with one and 2 doses of tenecteplase, respectively. Recombinant urokinase cleared 60% of catheters at 30 min and 73% overall. Alfimeprase demonstrated rapid catheter clearance with resolution in 40% of subjects within 5 min, 60% within 30 min, and 80% within 2 h. Additionally, urokinase prophylaxis decreased the incidence of catheter occlusions from 16–68% in the control group to 4–23% in the treatment group; in some studies, rates of catheter infections were also decreased in the urokinase group.

Conclusions

Thrombolytic agents successfully clear central venous catheter occlusions in most cases. Newer agents may act more rapidly and effectively than currently utilized therapies, but randomized studies with direct comparisons of these agents are needed to determine optimal management for catheter obstruction.     

Autosomal recessive hereditary spastic paraplegia—clinical and genetic characteristics of a well-defined cohort

We describe the clinical and genetic features of a well-characterized cohort of patients with autosomal recessive hereditary spastic paraplegia (ARHSP) in the province of Ontario. Patients with documented corticospinal tract abnormalities were screened by whole gene sequencing and multiplex ligation probe amplification for mutations in nine genes known to cause ARHSP. Of a cohort of 39 patients, a genetic diagnosis was established in 17 (44 %) and heterozygous mutations were detected in 8 (21 %). Mutations were most frequent in SPG7 (12 patients), followed by SPG11 (10 patients), PNPLA6 (SPG39, 2 patients), and ZFYVE26 (SPG15, 2 patients). Although there are associations between some clinical manifestations of ARHSP and specific genes, many patients are tested at an early stage of the disease when phenotype/genotype correlations are not obvious. Accurate molecular characterization of well-phenotyped cohorts of patients will be essential to establishing the natural history of these rare degenerative disorders to enable future clinical trials.     

Neurocognitive Functions in Pediatric Renal Transplant Patients

Neurocognitive dysfunction is one of the major complications of chronic renal failure (CRF). Uremic state during CRF encompasses a wide spectrum of neurobehavioral and neurological disturbances. Recent studies showed that the pathophysiology of neurocognitive dysfunction in CRF is related to plasma levels of uremic solutes. Successful renal transplantation improves renal, metabolic, and endocrine functions and the quality of life. The aim of our study was to determine the state of neurocognitive function in pediatric renal transplant recipients. We prospectively performed a neurological examination and neuropsychological test battery (Bender-Gestalt Test, Cancellation Test, and Visual and Auditory Number Assay Test) in 20 pediatric renal transplant recipients between 6 and 16 years of age. Twenty healthy children and 20 children with CRF were included in the study as the control groups. Mean age of the renal transplant recipients was 13.50 ± 3.40 years old. Mean evaluation time after transplantation was 2.0 ± 0.5 years. Bender-Gestalt Test result was abnormal in 40% of patients. The results of the Cancellation Test and the Visual and Auditory Number Assay Test showed significant decline in pediatric renal transplant patients when compared with the control. We found that neurocognitive dysfunction was frequent in pediatric renal transplantation patients. Awareness of this potential problem may be helpful for early recognition and treatment. Our findings suggest that periodic neurocognitive assessments may be indicated in transplant recipients.     

Acute Renal Failure and Mortality After Open-Heart Surgery in Infants

Acute renal failure (ARF) is a major complication in infants who undergo cardiac surgery. The aim of this investigation was to identify possible risk factors for ARF and mortality in this patients group. Out of 64 patients, 21 (32.8%) cases developed acute renal failure and overall mortality rate was 25%. The mortality rate was higher in the infants who developed ARF than those who did not (66.7% and 4.7%, respectively, p < 0.05). Also, ARF was positively correlated with mortality (r:0.70, p < 0.0001). The nonsurvivors had lower mean serum albumin than did the survivors (p < 0.05), and serum albumin level was negatively correlated with mortality (r = ? 0.34, p < 0.05). For the patients with serum albumin level < 3.5 g/dL, the unadjusted odds ratio for mortality was 4.3 (CI 95%:1.05 ? 17.86). Total bypass time and aorta clamping time were significantly longer in the nonsurvivor group than in the survivor group (p < 0.05 for both). In conclusion, the significant risk factors for mortality in these patients were development of ARF, low serum albumin level, and long total bypass and aorta clamping times, which may be predictive of poor prognosis.     

Early Proteinuria After Renal Transplantation and Allograft Outcomes

Background

Proteinuria is among the major and nonspecific sign of the renal disease. It is well known that late-onset proteinuria after renal transplantation has been associated with poor allograft outcomes and with mortality. Knowledge about the impact of early proteinuria on the various outcomes is limited. We have evaluated the utility of measuring early proteinuria in the management of pediatric renal transplant recipients.

Methods

We analyzed the effect of proteinuria at 3 months of posttransplantation on allograft rejection, graft loss, and estimated glomerular filtration rate (GFR) at 3 years. Proteinuria was assessed using 24-hour urine protein excretion. Renal biopsy was performed when elevated creatinine levels were elevated during routine follow-up and an acute rejection episode was proven with biopsy.

Results

Sixty-seven pediatric renal transplant recipients were included to the study. Mean follow-up time after transplantation was 48.8 ± 12.1 months. Thirty-nine recipients (58%) have proteinuria >500 mg/d. The relationship could not be shown between proteinuria at posttransplant month 3 and other outcomes parameters, such as graft loss and lower estimated GFR. A significant positive correlation between acute rejection and the proteinuria at posttransplant month 3 was shown.

Conclusion

We demonstrated that early proteinuria is a common finding in children after transplantation. Posttransplant early proteinuria cannot be used as a long-term prognostic marker of poor renal outcome. However, early proteinuria is associated with an high risk of acute rejection episodes. This would permit an opportunity for early intervention.     

New discoveries and directions for medical, dental and dental hygiene research: low temperature atmospheric pressure plasma

Abstract:  The study of plasma integrates physics, chemistry, biology, and engineering, and has recently engaged medicine and dental hygiene in research efforts. The study of plasma holds promise for a myriad of applications ranging from lasers and electronics, hazardous waste management, decontamination, sterilization and disinfection of foods, soil, water, instruments, to medical uses in wound healing and treating certain types of tumours and cancers. Plasma represents a new state-of-the-art sterilization and disinfection treatment for certain oral and enviornmental pathogens, heat-sensitive materials, contaminated medical waste, hard and soft surfaces, and ventilation systems may assist health care facilities in the management of various health concerns. The role that Low Temperature Atmospheric Pressure Plasma (LTAPP) could play in the inactivation of pathogenic microorganisms might prove to be a new, faster, noncorrosive, more economical alternative, as well as support green healthcare.     

基因芯片筛选尿道下裂雌激素敏感基因的研究

目的 寻找与尿道下裂发病密切相关的基因,探讨尿道下裂形成机制.方法 ①实验组为12例尿道下裂患儿,年龄6～12个月,平均8个月.尿道下裂中度5例,重度7例.组织标本取自尿道成形手术时切取的尿道板组织.②对照组为6例年龄匹配的男性患儿,留取包皮环切时的正常表皮组织.用Tri-Reagent分别提取总RNA,与含22 000个人类基因的寡核苷酸基因芯片杂交、洗脱、染色、扫描,基因强度变化行方差分析(ANOVA,P＜0.01)和Tukey分析,基因表达强度变化＞2倍作为有意义的基因,比较尿道下裂和正常组织之间基因表达差异.从上调表达的基因中选择雌激素敏感基因行RT-PCR,标本除上述患儿RNA外,再增加年龄配对的3例中度、1例重度尿道下裂和2例年龄配对的RNA作为对照,即对照、中度和重度尿道下裂患者RNA标本各8例,验证芯片结果.结果 尿道下裂组织与正常组织之间存在明显的基因表达差异,共筛选出表达强度变化＞2倍的基因94个,其中中度尿道下裂与正常比较,47个基因上调表达(P＜0.01);重度尿道下裂与正常比较,68个基因上调表达(P＜0.001);重度与中度比较,17个基因上调表达(P＞0.05).上调表达的基因中发现了4个雌激素敏感基因CYR61、结缔组织生长因子、ATF3和GADD45β,基因芯片和RT-PCR均证实其在尿道下裂组织中的表达明显高于正常对照.结论 异常表达的基因与尿道下裂的发生有关,尿道下裂组织中雌激素敏感基因上调表达参与了尿道下裂的发病机制.