Myringoplasty in children: factors influencing surgical outcome

Experiments were designed to evaluate whether guanosine 3',5'-cyclic monophosphate (cGMP)-mediated mechanisms contribute to vasodilation via propofol in rat mesenteric resistance arteries. Ring segments were suspended in the myograph system for isometric tension recording, and responses to propofol were tested in the presence and absence of methylene blue (MB), an inhibitor of guanylate cyclase. At concentrations > or = 1 microM, propofol caused concentration-dependent relaxation of vessel rings precontracted with U46619 (a thromboxane analog). The effect was not affected by N-monomethyl-L-arginine (L-NMMA; 50 microM). MB (5 microM) reversed propofol-induced vasodilation by 30% (p < 0.001). In contrast, MB has no effect on nifedipine-inhibited vasocontraction. The propofol-induced relaxation was further tested in rings incubated in Ca2+-free solution. U46619-induced contractions were significantly reduced by propofol (40 microM) but not by nifedipine (1 microM). Propofol reduced to a similar degree the contractions obtained to exogenously added calcium chloride in the absence and the presence of MB. Furthermore, propofol (10-100 microM) increased cGMP content in cultured bovine vascular smooth-muscle cells. Soluble guanylate cyclase inhibitors, such as MB and LY83583, attenuated this effect. This investigation suggests that propofol-induced relaxations in small arteries, in addition to inhibition of calcium influx, are mediated by increases of cGMP in the smooth muscle cells.     

Information booklet for parents of children surviving cancer

With increasing survival rates in pediatric oncology, the medical and psychosocial costs of cure are becoming apparent for the child and his family. The focus of our concern is now how to prevent and to reduce these adverse late effects of cancer and its treatment. To reduce the late psychosocial consequences for the child and its family a booklet was written for parents. We decided to address parents because of the young age of many children when treatment is completed, the essential role of parents in alleviating late effects for the child and his siblings, and the possibility to discuss the whole range of psychosocial late effects: those for the patient, the siblings, and for the parents themselves. The booklet acknowledges the specific emotional problems in patients, parents, and siblings that results from surviving childhood cancer and provides information and support on how to deal with them. The booklet can enhance open communication with the health care team about late consequences. In this way the booklet supports the further integration of medical and psychosocial aftercare.     

高压直流干扰大幅值管地电位产生原因及影响因素分析

基于实际的工程参数建立了高压直流干扰电场计算模型,利用数值模拟计算技术对高压直流干扰大幅值管地电位的产生原因进行探究。考察接地极与管道之间的间距、管道防腐层类型、管道长度及土壤结构等因素对高压直流干扰下管地电位的影响规律,得到高压直流干扰大幅值管地电位是在接地极与管道距离较近、防腐层的绝缘性能较高、管道长度较大及上低下高的土壤电阻率分层结构共同作用下产生的。      

Studies on the transmission potential of surviving microfilaremias after basic control of filariasis

After filariasis was basically controlled (the microfilarial rate was lower than 1%) in Henan Province in 1987, longitudinal observation of the disease has been carried out in all the province in order to study the regular pattern of growth and decline or the transmission potential of the disease. According to the distribution of filaria species and original microfilarial rate, 7 administrative villages in 7 counties were selected as surveillance sites. From 1988 to 1995, etiological and mosquito vector surveys were made continuously in all sites where no control measure was conducted. 10 surviving microfilaremic individuals became negative gradually over the first 6 years and no new microfilaremia was found. Since then, the microfilarial rate was zero. During the 8 years, 19 vector mosquitos were positive, with a total of 33 filarial larva. Culex pipiens pallens was the predominant mosquito species inside human dwelling in all sites. The man-biting rate of mosquitos for outdoor sleepers fluctuated greatly, the highest was 360.60 mosquitos per man per night and the lowest 7.20. The man-biting rate of mosquitos for sleepers inside mosquito-nets was approximately 1. The proportion of multiparous mosquitos also fluctuated greatly, the highest was 88.10% and the lowest 27.27%. According to the data described above, the man-biting rate of mosquitos which contained filaria L3 was less than 1 mosquito per man per transmission season. It is suggested that after the microfilarial rate was lower than 1%, the surviving microfilaremias became negative gradually in 3-5 years, and the transmission of the disease was blocked. Therefore, in the districts where filariasis was basically controlled, elimination of the disease was attainable.     

Liver transplantation in children with chronic end stage liver disease: factors influencing survival after transplantation

To identify pretransplant factors that are influencing survival after orthotopic liver transplantation a Cox proportional hazards regression model was applied to 118 children with chronic terminal liver failure transplanted at Medical School Hannover during the period of 1978 to 1994. The response variable was survival, as covariates a total of 19 pretransplant variables were entered--i.e. age, diagnosis (biliary cirrhosis, metabolic cirrhosis, postnecrotic cirrhosis, cryptogenetic cirrhosis) sex, laparotomy prior to OLT, height, weight, standard deviation scores for height and weight, date of first OLT, serum alanine aminotransferase, asparagine aminotransferase, albumin, total bilirubin, cholinesterase activity, glomerular filtration rate, and prothrombin time. Significant independent predictors of survival after OLT were bilirubin (P=0.0024), SDS for weight (P=0.034), and albumin (P=0.039). In a subsequent discriminant analysis cut off points for these variables could be identified--i.e., bilirubin >340 micromol/L, SDS for weight <-2.2 and albumin < 33 g/L. Patients with one or more of these risk factors were grouped as urgent indication group (n=76) and those with no risk factor as elective indication group (n=42). Comparing the posttransplantation survival in these groups there is a statistically significant difference at 1 year (57% vs. 90.5%) and 4 years (49% vs. 90.5%) after OLT (P=0.0001, log rank test). It is concluded that the risk of OLT is much higher if liver function is very poor. Optimal nutritional support prior to transplantation is mandatory to optimise the clinical status of the children and to improve the results of OLT.     

Project Support: engaging children and families in the educational process

The literature on dropout prevention reveals that a triumvirate of support--from the family, the school, and the community--is necessary to engage children in the educational process. This paper describes Project Support, a federally funded five-year program for at-risk youths that focused on alcohol, drug, and dropout prevention in four low-income, high-minority public school districts in the suburbs of New York City. Of several avenues taken, two were very effective: a school-based mentoring program designed for middle school students and the Outdoor and Environmental Education program that took place during summers and intermittently throughout the school year. The sense of achievement, bonding, and success experienced by participants was acknowledged by administrators, evaluators, parents, and other observers.     

Nutritional factors influencing the glucose/insulin system: chromium

Chromium (Cr) improves the glucose/insulin system in subjects with hypoglycemia, hyperglycemia, diabetes and hyperlipemia with no detectable effects on control subjects. Chromium improves insulin binding, insulin receptor number, insulin internalization, beta cell sensitivity and insulin receptor enzymes with overall increases in insulin sensitivity. There have been several studies involving Cr supplementation of subjects with NIDDM and/or lipemia and most have reported beneficial effects of Cr on the glucose/insulin system. In a recent study, Chinese subjects with NIDDM were divided into three groups of 60 subjects and supplemented with placebo, 100 or 500 micrograms of Cr as chromium picolinate 2 times per day for 4 months. Improvements in the glucose/insulin system were highly significant in the subjects receiving 500 micrograms twice per day with less or no significant improvements in the subjects receiving 100 micrograms twice per day after 2 and 4 months. In summary, Cr is involved in the control of the glucose/insulin system and the amount, and likely form of chromium, are critical when evaluating the role of chromium in this system.     

Spinal epidural abscess: evaluation of factors influencing outcome

OBJECTIVE: The goal of this study was to critically evaluate the predictive efficacy of various clinical factors in spinal epidural abscess influencing outcome after surgical and/or medical treatment. METHODS: A retrospective analysis of 41 cases of spinal epidural abscess treated at Henry Ford Hospital between 1984 and 1992 was performed. RESULTS: Thirty patients underwent open surgery and received antibiotic therapy, and 11 patients received medical treatment alone. After a mean follow-up period of 20.9 months (range, 4-45 mo), 24 patients (58.5%) had no or minimal deficits, 9 patients (22%) had severe paresis or plegia and/or bowel/bladder dysfunction, and 8 patients (19.5%) died. Univariate analysis revealed patient age, degree of thecal sac compression, spinal location, surgical findings, and septic presentation to be significantly associated with outcome. In multiple logistic regression analysis, increasing age and degree of thecal sac compression were the only factors with significant independent association with poor outcome (P = 0.01 for both). A simple grading system (Grades 0-III) was developed, with patient age, degree of thecal sac compression, and duration of symptoms as the determining criteria. The incidence of poor outcome for patients with Grade 0 was 0%, compared to 85.7% for patients with Grade III. CONCLUSION: We conclude that long-term outcome after treatment of spinal epidural abscess can be predicted with the use of the proposed grading scheme. Surgical drainage plus parenterally administered antibiotics remains the recommended treatment, although medical treatment alone can also be used for certain patients.     

Efficacy of lipid apheresis: definitions and influencing factors

The comparison of efficiency of currently available lipid apheresis systems has been hampered by different definitions of efficacy and poorly controlled apheresis conditions. This paper suggests definitions of efficacy and standardization of its determinants. The acute efficacy of risk factor reduction reflects the relative decrease of pathogen by a single treatment session compared to preapheresis levels. Standardization of treated plasma volume in relation to the patients plasma volume and correction of changes in plasma volume during the procedure are mandatory. Its determination is most useful in the technical evaluation of new systems. The long-term efficacy of risk factor reduction as compared to baseline is determined by mean interapheresis levels of e.g. LDL-C in the pseudo-steady-state after about 3 months of regular treatment. It is the major criterion for potential regression of coronary artery disease and absolute average plasma levels of 120 < or = mg/dl LDL-C should be attained. It is influenced by the acute efficacy of the system, apheresis frequency and rebound kinetics. The clinical efficacy is defined by apheresis induced reduction of coronary morbidity and mortality. It is influenced by long-term risk factor reduction, the selectivity of the system as well as the control of non-lipid risk factors. Apheresis related effects on coronary artery disease comprise functional improvements of hemorheology and vasomotion as well as morphological benefits like regression of luminal narrowing and plaque stabilization.(ABSTRACT TRUNCATED AT 250 WORDS)     

Review article: factors influencing antibiotic transfer across the gastric mucosa

The delivery of antimicrobial drugs to Helicobacter pylori within the stomach is poorly understood. The gastric environment represents a unique pharmacokinetic compartment, into which drug can be delivered directly following oral administration, or indirectly following intestinal absorption and transfer from the blood into the stomach across the gastric mucosa. Several methods have been used to study drug disposition across the gastric mucosa, including endoscopic biopsy studies, nasogastric intubation studies and animal models. Direct, or topical, delivery is limited by luminal drug degradation, drug formulation and the permeability of the mucus layer. Indirect, or systemic, delivery is limited by factors affecting the concentration gradient across the gastric mucosa and the permeability of the mucosa. These factors include intragastric pH, plasma protein binding, drug lipophilicity, the presence of active transport mechanisms, drugs that damage the gastric mucosa and inflammation secondary to H. pylori infection. Little is known about the last of these, and further research in this area should help in the rational approach to development of treatments against H. pylori.     

Human lymphocyte culture: intrinsic factors influencing the quality of chromosome preparations

In a cytogenetic study of the consecutive cell cycles (M1, M2 etc.) from human lymphocyte cultures after 5-bromodeoxyuridine incorporation followed by differential Giemsa staining, the metaphases of M2 and subsequent in vitro divisions have been found to spread better than those of M1 cells, as if the cells of in vitro generation suffer some membrane alterations. Moreover presence of S or G2 phase, leukocytes in a blood sample may result into early proliferation in a PHA stimulated culture system, so that the metaphase yield at 72 h will be larger than otherwise, a sizeable portion of which, being in M2 or subsequent cell cycles, will spread better. Thus such individual or transient intrinsic factors of haematologic state may influence the success of a leukocyte culture and the quality of chromosome preparation.     

Fatal cerebral gunshot wounds: factors influencing organ donation

Patients with clinical brain death following head injury are important potential cadaveric organ donors. We analyzed our series of cranial gunshot wounds with particular attention to the frequency and patterns of organ donation after fatal injuries. Sixty-six patients with gunshot wounds to the head, including 59 with intracranial involvement (43 male, average age 26 years) were seen during a 4-year period. Injuries were limited to the head in 50 of 59 patients. Overall mortality was 66 per cent. Predictors of mortality included Glasgow Coma Scale (GCS) of six or less (93%), self-inflicted gunshot wounds (75%), and computed tomography (CT) findings of bihemispheric injury (87%) or ventricular injury (82%). Of the 39 patients who died, 28 met standard criteria for brain death, and nine of these went on to organ procurement. Thirteen families refused donation, and six patients were not harvested for reasons including old age, pregnancy, suspicion of AIDS, coroner refusal, and failure to pursue consent. Principles essential to maximal organ retrieval include: 1) Recognition that patients suffering cerebral gunshot wounds represent potential organ donors and that certain factors are predictive of mortality; 2) Critical care/trauma team approach with standardized management and timely declaration of brain death; 3) Early search for family members and prompt notification of organ procurement agencies; 4) Sensitivity to cultural issues influencing donation; and 5) Programs to increase public awareness of organ donation.     

Referential communication: Some factors influencing communication efficiency.

Examined differences in message variables and listener response measures as a function of pleasant vs unpleasant content in a referential communication task. The 5 basic components of the referential communication model are speaker, listener, task, message, and listener response. 192 female undergraduates formed 96 pairs (86 pairs were already acquainted), and Ss participated in written and communication sessions. The "speaker" described pleasant or unpleasant pictures that the "listener" identified from among 5 similar alternatives. Measures of message style, listener responses, and speaker and listener traits yielded 40 variables whose factor analysis supported the model. Pleasant content was associated with greater diversity, shorter words, less verbal output, and longer pauses. For pleasant tasks, listener accuracy was related to a message style that included high productivity, more precise words, numerous speech errors, and few pauses; unpleasant task accuracy was related to few errors and pauses. The association of listener traits with message indices suggests that speakers adapt their message to a particular listener. (French abstract) (38 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Affinity liposomes in vivo: factors influencing target accumulation

To make universal and efficient liposome-based drug carriers, liposomes should be able to recognize and bind other targets beyond their natural targets, the cells of the reticuloendothial system. To make liposomes targeted, numerous methods to couple active substances, primarily, monoclonal antibodies, to the liposome surface have been developed. Resulting immunoliposomes (or affinity liposomes) demonstrate good targeting to cells and organs both in vitro and in vivo. However, the short circulation time of immunoliposomes prevented them from accumulating in targets with diminished blood flow or low antigen concentration. Long-circulating liposomes were prepared by coupling soluble and flexible polymers, such as polyethylene glycol, to the liposome surface. The mechanism of liposome steric protection with flexible polymers is based on the formation of dense "conformational cloud' by a grafted polymer over the liposome surface, and might be analyzed in terms of a statistical model of polymer solutions. By co-immobilization of specific antibodies and protecting polymers on the liposome surface, liposomes can be prepared combining both targetability and prolonged circulation in vivo. A biological model (experimental myocardial infarction in rabbit) was used to estimate the relative importance of different factors (liposome size and coating with protective polymer and/or specific antibody) for effective accumulation of liposomes in the target. Statistical analysis demonstrated that different types of liposomes have to be used in order to reach maximum absolute delivery of liposomes to the target, or maximum target-to-non-target ratio (relative delivery). Therefore, different liposomes should be used as carriers of diagnostic and therapeutic agents.     

Deterioration of intellect among children surviving leukemia: IQ test changes modify estimates of treatment toxicity.

Assessed the association of young age at treatment, cranial irradiation, and time since treatment with intellectual deterioration among 49 long-term survivors of childhood leukemia. Ss had been randomized to receive low-dose cranial radiation therapy or high-dose chemotherapy. Longitudinal assessments of intellect were conducted. No significant effects of treatment group or age at treatment were detected. A small but statistically significant decline in mean full-scale IQ was noted over time (M?=?–3.6). Reanalysis with IQ test version included as a covariate eliminated IQ declines found initially. Results suggest that there has been reduced toxicity of these methods of treatment and that the magnitude and direction of error introduced by changing tests may approximate the magnitude of adverse effects on IQ expected from treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

影响压延取向粘结磁体性能的因素

从分析压延取向对粘结磁体矫顽力等的机制入手,通过扫描电镜、图象仪等工龄研究了影响磁粉形貌及磁体性能的因素,结果表明：磁粉颗粒的径厚比（D／H）是影响磁体性能的关键因素,合适的径厚比能使 粉在取向过程中获得最大有效的取向力矩,同时又能使该应力所引起的晶格畸变最小,获得综合性能优越的磁体;还他磁粉预烧温度、混料方式、预烧助溶剂以及磁体压延取向工艺的混炼温度对磁体性能的影响,为制造磁粉和磁体提供工艺依据。     

Medulloblastoma originating from the superior cerebellar peduncle: a case report

A rare case of medulloblastoma originating from the superior cerebellar peduncle is reported. After tilting her neck to the right, a 4-year-old girl experienced a left-side hemiparesis for 3 months. Computed tomography (CT) scan and magnetic resonance image (MRI) showed an enhanced mass in the left tentorial incisura. The preoperative diagnosis was trochlear nerve neurinoma or tentorial meningioma, while the postoperative pathological diagnosis was medulloblastoma. Since medulloblastoma is thought to originate from the external granular layer, it is speculated that the external granular layer migrated through the superior cerebellar peduncle and changed to medulloblastoma.     

Growth factors: potential for the management of solid epithelial tumours

At present we are on the threshold of an enormous change in clinical practice. The application of molecular medicine has already started and the area of growth factor biology is particularly relevant to this endeavor (Figure 6) (Jankowski and Polak 1996). Perhaps the major limitation to this process is the rate at which the clinician can comprehend and then undertake carefully designed molecular studies in gastroenterology. In time monographs that specifically address the issue of molecular medicine in clinical gene analysis and manipulation may perhaps replace standard text books (see Jankowski and Polak, 1996).     

Acute renal failure: factors influencing nephrology referral and outcome

We investigated the incidence, factors affecting referral and outcome of acute renal failure (ARF), in an unselected (predominantly Caucasian) population in the Grampian region of Scotland served by a single renal unit. Case-notes were examined for all patients with a serum creatinine > or = 300 mumol/l. ARF (311 patients) was defined as a temporary rise in serum creatinine > or = 300 mumol/l, or, if the patient died during the acute illness, clinical features indicating acute deterioration of previously normal renal function. Advanced ARF at presentation (51 of the 311 with ARF) was defined as a first recorded serum creatinine > or = 500 mumol/l. Patients were classified into low-, medium-, and high-risk groups according to presence of comorbidity and age. The annual incidence of ARF was 620/million population (pmp), that of advanced ARF 102 pmp. The age-related incidence of ARF ranged from 30 pmp in the age group (0-19 years) to 4266 pmp in the age group > 80 years. Overall, 22% were referred to a nephrologist (34% after excluding those with advanced cancer and age > 80 years). Referral of patients decreased from 100% in the age group 0-19 to 5% in those > 80 years. Referrals in the low-, medium- and high-risk groups were 75%, 30% and 14%, respectively. Patient survival at 2 years was 80%, 42% and 19% for low-, medium-, and high-risk groups, respectively (86%, 44% and 32% for referred patients). Referral and outcome in patients with ARF were significantly influenced by age and presence of comorbidity at presentation.     

Penetrating cardiac wounds: prospective study of factors influencing initial resuscitation

A prospective study of 66 consecutive patients with cardiac wounds seen over a 27-month period is reported. No patient was excluded. Patients were stratified by injury mechanism and by physiologic scoring at admission using the cardiovascular-respiratory elements of the Trauma Score (CVRS). Admission cardiac rhythm was obtained in patients with a CVRS of 0 and a Glasgow Coma Scale (GCS) score of 3. Information concerning the anatomic extent of the cardiac wound, the presence or absence of tamponade, and the degree of injury to other structures was also collected prospectively. Seventy percent of the cardiac wounds were caused by gunshots. The probability of successful resuscitation was significantly related to mechanism of injury and physiologic condition on arrival. Among patients arriving with a CVRS of 0 and a GCS score of 3, survival correlated with cardiac rhythm. Pericardial tamponade did not prove to be an independent predictor of early survival. The presence of tamponade was statistically linked to the mechanism of injury. Transport by non-official conveyance was associated with a higher CVRS on arrival. Intoxication with alcohol or cocaine had no evident effect on resuscitation probability.