吸氧对听感觉门控P50的影响

目的研究呼吸纯氧对健康人听感觉门控P50的影响。方法右利手、健康男性大学生志愿者28名,根据随机数字表分为对照组(n=12)和实验组(n=16)。佩戴面罩,对照组呼吸空气,实验组呼吸医用纯氧60 min。应用条件-测试刺激,记录吸氧前(pre0)、吸氧20 min(Oxy20)、吸氧50 min(Oxy50)、吸氧后30 min(post30)的脑电图,计算听觉P50潜伏期和P50感觉门控电位(S1与S2振幅之差)。结果 S1刺激在4个时间点各组P50潜伏期相对稳定(P0.7);吸氧50 min时,实验组比对照组P50潜伏期缩短(P0.05)。S2刺激在4个时间点各组P50潜伏期相对稳定(P0.30),两组间比较无显著性差异(P0.05)。对照组P50门控电位比较稳定(P=0.70),而实验组随吸氧时间逐渐延长,电位越来越高,停止吸氧后,电位迅速回落,Oxy20和post30(P=0.04)、Oxy50和post30(P=0.02)相比均有显著性差异。组间比较,4个时间点均无显著性差异(P0.05)。结论健康人吸60 min纯氧,可能缩短对刺激的反应时间,有增强听觉门控电位的趋势。     

In vivo anti-plasmodial activities and toxic impacts of lime extract of a combination of Picralima nitida,Alstonia boonei and Gongronema latifolium in mice infected with Chloroquine-sensitive Plasmodium berghei

Background

Lime extracts of powdered combination of seeds of Picralima nitida, stem bark of Alstonia boonei and leaves of Gongronema latifolium is a common remedy used in the treatment of malaria in South Western Nigeria.

Objective

To determine the antiplasmodial activities of the combined herbal extracts and its impact on the haematological, hepatological and renological parameters in mice.

Methods

The 4-day suppressive and curative tests were used to assess the antiplasmodial activities of the extract in mice infected with chloroquine-sensitive Plasmodium berghei at concentration of 200mg/kg, 400mg/kg and 800mg/kg body weight. The haematological parameters including red blood cells, white blood cells, packed cell volume and haemoglobin count were analysed with an auto analyser. The activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) were determined, while urea, protein and creatinine were analysed by standard procedural methods.

Results

The 4-day suppressive test revealed that the test extract achieved percentage suppression of 39.0%, 41.6% and 54.68% for the 200mg/kg, 400mg/kg and 800mg/kg concentration respectively. Additionally, the curative test achieved a high percentage suppression of 80.97%, 83.84% and 86.16% at the 200mg/kg, 400mg/kg and 800mg/kg concentration respectively. The extracts did not induce significant change on haematological parameters (P>0.05), while significant elevation in the values of the ALT and AST (P<0.05) was observed and elevation of creatinine (P<0.05) at 800mg/kg.

Conclusions

The results support the traditional use of the herbal combination in the treatment of malaria, however the liver cells were impacted by the extracts in bioassay conducted with mice.     

Laminar flow reduces cases of surgical site infections in vascular patients

Introduction

Numerous strategies are employed routinely in an effort to lower rates of surgical site infections (SSIs). A laminar flow theatre environment is generally used during orthopaedic surgery to reduce rates of SSIs. Its role in vascular surgery, especially when arterial bypass grafts are used, is unknown.

Methods

A retrospective review of a prospectively maintained database was undertaken for all vascular procedures performed by a single consultant over a one-year period. Cases were performed, via random allocation, in either a laminar or non-laminar flow theatre environment. Demographic data, operative data and evidence of postoperative SSIs were noted. A separate subgroup analysis was undertaken for patients requiring an arterial bypass graft. Univariate and multivariate logistical regression was undertaken to identify significant factors associated with SSIs.

Results

Overall, 170 procedures were analysed. Presence of a groin incision, insertion of an arterial graft and a non-laminar flow theatre were shown to be predictive of SSIs in this cohort. In the subgroup receiving arterial grafts, only a non-laminar flow theatre environment was shown to be predictive of an SSI.

Conclusions

This study suggests that laminar flow may reduce incidences of SSI, especially in the subgroup of patients receiving arterial grafts.     

Fluorescence in situ hybridization mapping of translocations and deletions involving the short arm of human chromosome 12 in malignant hematologic diseases

Translocations and deletions of the short arm of chromosome 12 [t(12p) and del(12p)] are common recurring abnormalities in a broad spectrum of hematologic malignant diseases. We studied 20 patients and one cell line whose cells contained 12p13 translocations and/or 12p deletions using fluorescence in situ hybridization (FISH) with phage, plasmid, and cosmid probes that we previously mapped and ordered on 12p12-13. FISH analysis showed that the 12p13 translocation breakpoints were clustered between two cosmids, D12S133 and D12S142, in 11 of 12 patients and in one cell line. FISH analysis of 11 patients with deletions demonstrated that the deletions were interstitial rather than terminal and that the distal part of 12p12, including the GDI-D4 gene and D12S54 marker, was deleted in all 11 patients. Moreover, FISH analysis showed that cells from 3 of these patients contained both a del(12p) and a 12p13 translocation and that the affected regions of these rearrangements appeared to overlap. We identified three yeast artificial chromosome (YAC) clones that span all the 12p13 translocation breakpoints mapped between D12S133 and D12S142. They have inserts of human DNA between 1.39 and 1.67 Mb. Because the region between D12S133 and D12S142 also represents the telomeric border of the smallest commonly deleted region of 12p, we also studied patients with a del(12p) using these YACs. The smallest YAC, 964c10, was deleted in 8 of 9 patients studied. In the other patient, the YAC labeled the del(12p) chromosome more weakly than the normal chromosome 12, suggesting that a part of the YAC was deleted. Thus, most 12p13 translocation breakpoints were clustered within the sequences contained in the 1.39 Mb YAC and this YAC appears to include the telomeric border of the smallest commonly deleted region. Whether the same gene is involved in both the translocations and deletions is presently unknown.     

Management of a floating sternum after repair of pectus excavatum

PURPOSE: The aim of this study was to examine the authors' experience with patients who have floating sternum after correction of pectus excavatum via the classical Ravitch procedure. A floating sternum is defined as a sternum in which the only attachment to the chest wall is its superior (cranial) border, and in which the body is secured only by the manubrium and whatever lateral and inferior fibrous bands are present. Typically, a floating sternum is caused by either extensive resection of the costal cartilages and perichondrium during correction of pectus excavatum or failure of proper regrowth of these cartilages. METHODS: The authors retrospectively assessed the charts of all patients diagnosed with a floating sternum noting age at original correction of pectus excavatum, time from original correction of pectus excavatum to diagnosis of floating sternum, age at correction of floating sternum, complaints before stabilization of the sternum, methods of repair, and postoperative complications. RESULTS: Between July 1993 and June 1999, floating sternum was diagnosed in 7 patients. The mean age of patients who underwent operative correction of a floating sternum was 28.9 years (range, 16 to 42 years). The mean time interval between original correction of pectus excavatum, or "redo," and diagnosis of a floating sternum was 9.9 years (range, 2 to 20 years). Complaints before correction of the floating sternum included sternal pain and instability, exercise intolerance, and difficulty breathing. Operative repair consisted of mobilizing the lateral and inferior edges of the sternum, detaching the fibrous perichondrium, performing anterior sternal osteotomies, and finally supporting the sternum with substernal Adkins struts. All 7 patients had successful stabilization of the sternum. Two of 7 patients underwent 2 procedures to successfully stabilize the sternum. One patient has Adkins struts still in place because of hematopoetic malignancy. Six of 7 patients are now without symptoms. CONCLUSIONS: A floating sternum is a morbid phenomenon that may manifest many years after the original procedure. It can cause significant sternal pain, chest wall instability, and respiratory dysfunction, which are the hallmark indications for correction. Repair of a floating sternum can be accomplished successfully.     

The multi-institutional validation of the new screening index for physical child abuse

Background/Purpose

There is currently no evidence-based screening instrument to assist in the detection of physical child abuse patients. The screening index for physical child abuse (SIPCA) was previously developed as a potentially new tool for this need. It is a scale that assigns point values, on the basis of variable weights from logistic regression models, to age and patterns of injuries (including fracture of base or vault of skull, contusion of eye, rib fracture, intracranial bleeding, multiple burns), with higher scores indicating greater suspicion for abuse. The purpose of this study is to validate this new tool in another independent data set.

Methods

A cross-sectional hospital discharge database from 1961 hospitals in 17 states is used (n = 58558). Children aged 14 years or younger with International Classification of Diseases, Ninth Revision, Clinical Modification codes 800 to 959 are included for analysis. Child abuse cases are identified by E codes and certain International Classification of Diseases, Ninth Revision, Clinical Modification codes in the 995.5x range. Screening index for physical child abuse performance is evaluated by discrimination (receiver operating characteristic) and goodness of fit (pseudo r²).

Results

A total of 447 abused patients (0.76%) was identified. The receiver operating characteristic of SIPCA in this data set is 0.89 as compared with 0.86 in the development data set. The pseudo r² of SIPCA in this data set is 0.26 as compared with 0.28 in the development data set. A SIPCA score of 3 has a sensitivity of 86.6% and a specificity of 80.5% for detecting physical abuse; raising the threshold to a score of 4 improves the specificity to 93.1% but at a loss of sensitivity to 71.8%.

Conclusions

The validity of the new SIPCA instrument is supported by its performance in an independently derived data set. A score of 3 on SIPCA represents a balanced trade off in the sensitivity and specificity of the instrument in detecting physical abuse and is an optimal threshold above which to begin considering abuse in differential diagnosis. Application of the instrument could assist clinicians in detecting physical child abuse cases among pediatric trauma patients.     

Characteristics and outcomes of rhabdomyosarcoma patients with isolated lung metastases from IRS-IV

Purpose

To better understand outcomes in children with rhabdomyosarcoma (RMS) and lung-only metastatic disease, the authors reviewed the experience from Intergroup Rhabdomyosarcoma Studies IV Pilot and IV.

Methods

Patients with lung-only (n = 46) vs other sites of metastatic disease (n = 234) were reviewed using patient charts and the database of Children's Oncology Group (COG).

Results

Sixteen percent of patients with RMS and metastatic disease had isolated lung metastases. Thirty-one (67%) had more than 5 metastatic lung lesions. These were bilateral in 34 (74%). Only 6 patients were biopsied at diagnosis. Sixteen children (35%) did not receive any lung radiotherapy. Patients that received lung radiotherapy had fewer lung recurrences (P = .04), although this has no significant impact on overall survival (OAS, 47% radiotherapy vs 31% no radiotherapy). Compared with patients with other sites of metastatic disease, patients with lung-only metastases have a greater proportion of favorable histology (67% vs 39%, P = .0017), negative nodal involvement (67% vs 32%, P = .0013), and parameningeal primaries (39% vs 12%) and a smaller proportion of extremity primaries (20% vs 33%, P = .0005 for site of primary tumor). Overall survival at 4 years for lung-only metastases was not significantly different from other single-site metastasis (42% vs 34%). Survival was not improved for unilateral disease or fewer than 5 metastatic lesions. Factors associated with diminished OAS include unfavorable histology (P = .0001) and age >10 years (P = .015).

Conclusions

Children with RMS and lung-only metastases usually present with extensive bilateral disease that is frequently not biopsied nor given protocol-recommended radiotherapy (XRT). However, outcome is comparable, although slightly better, than patients with other single-site metastasis.     

Spinal injuries in children

Background/purpose

Traumatic spinal injury (TSI) is an uncommon source of morbidity and mortality in children. The aim of this study was to describe childhood TSI in a single level 1 urban pediatric trauma center.

Methods

The authors retrospectively analyzed all children younger than 14 years with TSI, treated at a level I pediatric trauma center between 1991 and 2002 (n = 406, 4% total registry). All children were stratified according to demographics, mechanisms, type and level of injury, radiologic evaluations, associated injuries, and mortality.

Results

The mean age was 9.48 ± 3.81 years. The most common overall mechanism of injury was motor vehicle crash (MVC; 29%) and ranked highest for infants. Falls ranked highest for ages 2 to 9 years. Sports ranked highest in the 10 to 14 year age group. Paravertebral soft tissue injuries were 68%. The most common injury level was the high cervical spine (O-C4). The incidence of spinal cord injury without radiologic abnormality (SCIWORA) was 6%. Traumatic brain injury (37%) was the most common associated injury. Overall mortality rate was 4% in this urban catchment.

Conclusions

TSI in children requires a different preventive and therapeutic logarithm compared with that of adults. The potential devastating nature of TSI warrants that the health care team always maintains a high index of suspicion for injury. Future prospective studies are needed to further elucidate injury patterns.