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The epidemiology of prostate cancer.

The etiology of prostate cancer remains virtually unknown. Although there are a number of new leads with regard to risk factors for prostate cancer, more research is required to confirm them. There is little purpose in conducting further case-control studies of prostate cancer-particularly since the use of PSA testing has become wide-spread. Instead, future epidemiologic studies should focus on prostate tumor subclassification, in terms of method of detection, markers of biological "aggressiveness," and genetic changes. Many of these new leads involve the possible influence of polymorphisms in key genes involved in important physiologic processes in the prostate. To fully explore the complexity of interrelationships between the several elements in these pathways will require large cohort studies in which blood is sampled prior to diagnosis. Such studies will be important for identifying which modifiable aspects of lifestyle (such as diet, alcohol, tobacco, physical activity) might be targeted for intervention, to reduce risk. The detection of early prostate cancers by PSA testing relatives of men with prostate cancer has affected the prevalence of phenocopies and, hence, the meaningfulness of risk estimation in prostate cancer families. Because multiple-case families form the substrate for gene hunting via linkage analysis, this phenocopy phenomenon is going to cause considerable confusion and wasted effort. Presently, men with a family history of prostate cancer can be provided with little advice in terms of preventive action. It is likely that one or more genetic mutations associated with a high risk for prostate cancer will be identified in the near future. Even so, the risks probably will be similar to those for mutations in the first two breast cancer genes--informative for very few families. It is difficult to foresee, as and when high-risk mutation carriers are identified, what advice should be offered to them: prophylactic prostatectomies seem to have less attraction than do prophylactic mastectomies for women at high risk of breast cancer. This issue becomes more complex when considering counseling on the basis of a genetic profile involving many low-risk polymorphisms. Hopefully, such genetic screening should occur only after its efficacy has been established; when there is a better understanding of prostate biology, tumor heterogeneity, and prognosis; and when there are proven treatment or prevention options available. Prevention is held to be better than cure, and there are some potentially interesting chemopreventive agents that require careful trial before public health initiatives can be promoted. Potential candidates include vitamin E, selenium, zinc, and lycopene as dietary supplements. There are other agents that may be appropriate for pharmaceutical development, including inhibitors of COX-2 and IGF-1 activity. It is important that chemoprevention trials are followed-up for a sufficient period of time and that other endpoints also are captured, because the supplementation of diets with superphysiologic doses of individual micronutrients sometimes has caused unexpected and unwanted results--for example, an 18% increase in lung cancers observed in the beta-carotene arm of the ATBC trial.

Body Composition↗

Endothelin receptor antagonist bosentan improves microcirculatory blood flow in splanchnic organs in septic shock.

OBJECTIVE: Splanchnic ischemia is believed to play an important role in the development of multiple organ dysfunction in septic shock. The vasoconstrictor peptide endothelin can produce an intense and sustained splanchnic vasoconstriction and is increased in sepsis. The aim of this investigation was to study the effects of an endothelin antagonist on microcirculatory blood flow in multiple abdominal organs during septic shock. DESIGN: Prospective, controlled animal study. SETTING: University-affiliated research laboratory. SUBJECTS: Fifteen anesthetized and mechanically ventilated pigs. INTERVENTIONS: Septic shock was induced by fecal peritonitis. After 120 mins of sepsis, eight animals received 10 mg/kg bosentan intravenously followed by an intravenous infusion at 5 mg x kg-1 x hr-1 whereas seven (controls) received isotonic saline. At 240 mins after induction of sepsis both groups received hydroxyethyl starch, 20 mL/kg intravenously, to convert hypodynamic septic shock to hyperdynamic sepsis. MEASUREMENTS AND MAIN RESULTS: Microcirculatory blood flow was measured simultaneously and continuously in the jejunal muscularis, pancreas, liver, kidney, skeletal muscle, and gastric, jejunal, and colon mucosa by using a multiple-channel laser Doppler flow meter. After 120 mins, all animals had developed signs of hypodynamic sepsis with decreased cardiac index, mean arterial blood pressure, and gastric mucosal pH. Microcirculatory blood flow in the pancreas and liver had decreased by 20% and in the jejunal muscularis by >40% (p <.01) whereas it remained virtually unchanged in the gastric, jejunal, and colonic mucosa. After 240 mins, cardiac index, mean arterial blood pressure, gastric mucosal pH, and microcirculatory blood flow in the gastric mucosa, colon mucosa, jejunal muscularis, and pancreas had all deteriorated in the controls, whereas in the bosentan-treated group, cardiac index and microcirculatory blood flow in the pancreas, gastric, and colon mucosa improved. During hyperdynamic sepsis, cardiac index increased above baseline in both groups but significantly more in the bosentan group. In the control group, microcirculatory flow returned to baseline in most tissues except in skeletal muscle and jejunal muscularis. In the bosentan group, microcirculatory flow returned to or increased above baseline in all tissues except in the muscularis of the jejunum. CONCLUSIONS: The endothelin receptor antagonist bosentan significantly improved microcirculatory blood flow in many splanchnic organs and in peripheral tissues during septic shock. The results of this study are consistent with the hypothesis that endothelin plays an important role in the regulation of microcirculatory blood flow in splanchnic as well as in peripheral tissues during septic shock.

Acid-Base Equilibrium↗

At what level of coronary heart disease risk should a statin be prescribed?

Statin therapy has been conclusively shown to offer patients clinical benefit, virtually irrespective of their baseline risk status. However, the absolute risk reductions observed in different clinical trials, which have recruited patients across a spectrum of lipid levels and vascular disease states, show that baseline global risk determines the absolute benefit gained and in turn will specify the number of patients needed to be treated in order to realize this benefit. Global risk assessment is therefore central to the clinically meaningful use of statin therapy, and a strong case is now argued in the literature for a high-risk primary prevention strategy that goes hand in hand with standard secondary prevention. The routine use of Framingham-based risk assessment tools is advocated because these are the most widely evaluated and have been repeatedly shown to predict the risk of coronary heart disease accurately in western populations. The risk threshold in primary prevention that should determine pharmacological intervention is the subject of controversy. The currently used annual risk figure of 3% would clearly capture all very high-risk individuals but would also deny treatment to many individuals who will subsequently die from their first coronary event. Although a 1.5% annual risk threshold is economically untenable in the present UK health system, a level of 2% is, we believe, both achievable and affordable.

Age Factors↗

Employer-sponsored long-term care insurance: best practices for increasing sponsorship.

Behind the enthusiasm of policymakers for long-term care (LTC) insurance is the belief that increased ownership of private LTC insurance will reduce the government's future liability for financing the nation's LTC needs, currently projected by the Congressional Budget Office to increase by 2.6 percent annually between 2000 and 2040. Some observers say that sustained economic growth could keep these increased expenditures at the same share of total GDP; others argue that current federal expenditure trends will become unsustainable without large tax increases. The potential of the employer-sponsored group LTC market to stave off a national LTC financing crisis has recently started to receive popular notice in the news media. However, for the potential of the group LTC market to be realized, there must be widespread employer sponsorship of group LTC plans and significant participation levels among eligible employees in these plans. The present analysis of industry data estimates the LTC plan sponsorship rate for all U.S. employers with 10 or more employees at 0.2 percent. The sponsorship rate among large employers is significantly higher (8.7 percent). The greatest growth opportunities are projected to lie in the smaller employer market, because it is enormous and virtually untapped. Nonsponsors cite a variety of barriers to employer sponsorship of LTC plans. For many nonsponsors, the most important obstacles are the intrinsic characteristics of their work forces: employees are too young, transient, part-time, and/or low-income to be suitable for LTC insurance. For many others, lack of awareness and low priority are the primary obstacles. Because group LTC insurance has been widely available for only 10 years, many benefits managers view it as "too new and untested." Prior to the passage of the Health Insurance Portability and Accountability Act (HIPAA), in August 1996, the tax treatment of long-term care insurance premiums was unclear because Congress had not addressed the issue and the Internal Revenue Service had not issued clear guidance. In essence, HIPAA served to clarify the tax status of LTC insurance and establish product criteria for tax qualification. The interventions contained in HIPAA appear to have been insufficient to stimulate coverage growth rates that will meaningfully reduced the future burden on government financing of LTC. Although employment-based LTC insurance appears to be the best mechanism for mass expansion of coverage at affordable rates, the data suggest that employer sponsorship of LTC plans is relatively rare, especially among smaller employers, and that sponsorship rates may not dramatically increase without significant investments in employer education and new incentives.

Adult↗

Inpatient clinical research: its importance in psychiatry and psychopharmacology.

We have outlined the essential components found in an inpatient psychiatry research unit from the point of patient recruitment through discharge. In virtually every phase of a patient's hospitalization on the unit, there is the potential for significant tension between research and clinical goals. We conclude that, as Braff and associates have suggested, clinical and research interests are compatible when both receive appropriate support. We have also discussed the potential advantages of an inpatient research setting for patient care. Because of the washout period, there is greater opportunity for an extended diagnostic assessment and response to the therapeutic milieu alone. The attention and priority patients receive during the research phase can be of significant therapeutic benefit. Findings from research protocols can be used to help with diagnosis and clinical care. Working on an inpatient research unit provides residents and other trainees with special learning experiences. In particular, observational and diagnostic skills are sharpened. Techniques of non-pharmacologic behavioral management are added to the trainees' repertoire of therapeutic interventions. By nature, the research experience promotes creative thinking and problem solving. In this era of fiscal restrictions and cost accountability in medicine, potential advantages for immediate patient care and for staff training are only secondary reasons which justify the existence of inpatient research centers in psychiatry. We must also ask what specific and unique research information an inpatient research setting offers compared to less expensive outpatient research environments. The first factor to be considered is the ability to study individuals whose illness is so severe as to make outpatient management difficult or impossible. It is becoming increasingly clear that for many categories of psychiatric disorders, there is a spectrum of severity of possible behavioral manifestations seen in affected individuals. In depressive illness, for example, the spectrum of expression appears to range from dysthymic disorder to major depressive disorder with psychotic features. Individuals with more severe symptomatology tend to create the greater cost to society because of their correspondingly greater degree of dysfunctional behavior, need for repeated and extended hospitalization, requirement for social services, etc. Such individuals, therefore, need to be studied in a research setting at least as much as patients with milder manifestations of psychiatric illness. This would not be possible without the control, structure, and staffing found in an inpatient setting.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

Esophageal electrodes allow precise assessment of cardiac output by bioimpedance.

OBJECTIVES: To analyze the impact of the position of the thoracic external electrodes on the values of cardiac output measured by electrical bioimpedance and to compare the results obtained by bioimpedance with those values determined by thermodilution in critically ill patients. DESIGN: Open, prospective, comparative trial. SETTING: ICU of a teaching hospital. PATIENTS: Twenty healthy volunteers and ten critically ill patients. INTERVENTIONS: Measurements of cardiac output by bioimpedance at rest and after physical activity in normal volunteers and after changing the neck or xiphoid electrodes. Comparisons of cardiac output obtained by thermodilution and bioimpedance with internal and external electrodes in patients. MEASUREMENTS AND MAIN RESULTS: Mean +/- SD values are presented. Cardiac output values at rest and after exercise were 6.7 +/- 1.3 and 10.8 +/- 2.6 L/min at rest and after exercise, respectively (p less than .001). Displacement of the xiphoid electrodes 3 cm in the caudal direction was accompanied by a decrease of the mean cardiac output from 7.1 +/- 1.2 to 5.8 +/- 1.3 L/min (p less than .001) and displacement 3 and 6 cm cranially was accompanied by increases in cardiac output from 7.1 +/- 1.2 to 8.1 +/- 1.4 L/min (p less than .001) and 8.6 +/- 1.5 L/min (p less than .001), respectively. In the ten patients, cardiac output measurements were virtually identical when results obtained by thermodilution (6.7 +/- 3.1 L/min) were compared with those results obtained by bioimpedance using internal esophageal (6.6 +/- 3.1 L/min), but not external (4.7 +/- 1.6 L/min) electrodes. CONCLUSIONS: a) The values of cardiac output derived from measurements obtained by bioimpedance using internal electrodes were comparable with those values derived from thermodilution. b) Values of cardiac output from bioimpedance studies with external electrodes were dependent on the position of the xiphoid electrodes.

Adult↗

Status of nonoperative management of blunt hepatic injuries in 1995: a multicenter experience with 404 patients.

INTRODUCTION: Nonoperative management is presently considered the treatment modality of choice in over 50% of adult patients sustaining blunt hepatic trauma who meet inclusion criteria. A multicenter study was retrospectively undertaken to assess whether the combined experiences at level I trauma centers could validate the currently reported high success rate, low morbidity, and virtually nonexistent mortality associated with this approach. Thirteen level I trauma centers accrued 404 adult patients sustaining blunt hepatic injuries managed nonoperatively over the last 5 years. Seventy-two percent of the injuries resulted from motor vehicle crashes. The mean injury severity score for the entire group was 20.2 (range, 4-75), and the American Association for the Surgery of Trauma-computerized axial tomography scan grading was as follows: grade I, 19% (n = 76); grade II, 31% (n = 124); grade III, 36% (n = 146); grade IV, 10% (n = 42); and grade V, 4% (n = 16). There were 27 deaths (7%) in the series, with 59% directly related to head trauma. Only two deaths (0.4%) could be attributed to hepatic injury. Twenty-one (5%) complications were documented, with the most common being hemorrhage, occurring in 14 (3.5%). Only 3 (0.7%) of these 14 patients required surgical intervention, 6 were treated by transfusions alone (0.5 to 5 U), 4 underwent angio-embolization, and 1 was further observed. Other complications included 2 bilomas and 3 perihepatic abscesses (all drained percutaneously). Two small bowel injuries were initially missed (0.5%), and diagnosed 2 and 3 days after admission. Overall, 6 patients required operative intervention: 3 for hemorrhage, 2 for missed enteric injuries, and 1 for persistent sepsis after unsuccessful percutaneous drainage. Average length of stay was 13 days. Nonoperative management of blunt hepatic injuries is clearly the treatment modality of choice in hemodynamically stable patients, irrespective of grade of injury or degree of hemoperitoneum. Current data would suggest that 50 to 80% (47% in this series) of all adult patients with blunt hepatic injuries are candidates for this form of therapy. Exactly 98.5% of patients analyzed in this study successfully avoided operative intervention. Bleeding complications are infrequently encountered (3.5%) and can often be managed nonoperatively. Although grades IV and V injuries composed 14% of the series, they represented 66.6% of the patients requiring operative intervention and thus merit constant re-evaluation and close observation in critical care units. The optimal time for follow-up computerized axial tomography scanning seems to be within 7 to 10 days after injury.

Adolescent↗

Accuracy of in vivo coronary plaque morphology assessment: a validation study of in vivo virtual histology compared with in vitro histopathology.

OBJECTIVES: The goal of the present study was to compare the accuracy of in vivo tissue characterization obtained by intravascular ultrasound (IVUS) radiofrequency (RF) data analysis, known as Virtual Histology (VH), to the in vitro histopathology of coronary atherosclerotic plaques obtained by directional coronary atherectomy. BACKGROUND: Vulnerable plaque leading to acute coronary syndrome (ACS) has been associated with specific plaque composition, and its characterization is an important clinical focus. METHODS: Virtual histology IVUS images were performed before and after a single debulking cut using directional coronary atherectomy. Debulking region of in vivo histology image was predicted by comparing pre- and post-debulking VH images. Analysis of VH images with the corresponding tissue cross section was performed. RESULTS: Fifteen stable angina pectoris (AP) and 15 ACS patients were enrolled. The results of IVUS RF data analysis correlated well with histopathologic examination (predictive accuracy from all patients data: 87.1% for fibrous, 87.1% for fibro-fatty, 88.3% for necrotic core, and 96.5% for dense calcium regions, respectively). In addition, the frequency of necrotic core was significantly higher in the ACS group than in the stable AP group (in vitro histopathology: 22.6% vs. 12.6%, p = 0.02; in vivo virtual histology: 24.5% vs. 10.4%, p = 0.002). CONCLUSIONS: Correlation of in vivo IVUS RF data analysis with histopathology shows a high accuracy. In vivo IVUS RF data analysis is a useful modality for the classification of different types of coronary components, and may play an important role in the detection of vulnerable plaque.

Aged↗

Virtual reality simulation of fluoroscopic navigation.

Surgical navigation systems assist surgeons by tracking targets attached to the patient's bones and to the surgical tools. Fluoroscopic navigation is a technology that adds "live" imaging to surgical navigation. In order to identify the limitations and potential sources of errors in fluoroscopic navigation, a virtual environment is created in which all the key steps of fluoroscopic navigation can be rehearsed. This provides a low-cost, highly portable, and radiation-free training environment with the ability of instant accuracy validation and reliable measurement of trainee progress. This virtual environment also is suitable for comparing different fluoroscopic registration techniques and protocols. Although the imaging component of the navigation is simulated, physical interaction with the environment can be modeled at different levels; from a fully virtual environment, to miniature models, to life-size dummies and cadavers. Each of these options satisfies different specific training needs, such as the need for portability and easy setup to the need for a completely realistic simulation of the entire clinical environment and operating procedure. In this study, we present the example of a system based on a scaled-down model with a specific focus on analyzing and training bony landmark localization using fluoroscopic navigation.

Computer Simulation↗

Multipoint pulmonary vascular pressure-cardiac output plots in conscious dogs.

To characterize quantitatively the relationships among pulmonary vascular pressures (P) and cardiac output (Q) in conscious dogs, multipoint plots of pulmonary arterial (PAP), pulmonary capillary wedge (PCWP), PAP - PCWP, and left atrial (LAP) pressure versus Q were generated by graded constriction of the thoracic inferior vena cava (IVC) to vary Q. Slopes and extrapolated pressure intercepts from linear regression fits to the P/Q plots were determined for three inspired oxygen tensions: normoxia, hyperoxia, and hypoxia. During normoxia (arterial Po2 87 +/- 1 Torr), the extrapolated pressure intercepts for PAP, PCWP, and PAP - PCWP were virtually 0 mmHg, and for LAP, substantially negative (-5.5 +/- 1.1 mmHg; P less than 0.01). Hyperoxia (Po2 365 +/- 28 Torr) had no effect on any of the P/Q plots. In contrast, hypoxia (Po2 51 +/- 1 Torr) significantly increased the intercepts (P less than 0.01) as well as the slopes (P less than 0.05) of PAP and PAP - PCWP versus Q, but produced only minor changes in PCWP and LAP versus Q. These hypoxia-induced changes in intercepts, perhaps related to changes in critical closing pressures, demonstrate the limitations of pulmonary vascular resistance calculations (quotient of pressure gradient and Q) in quantifying changes in pulmonary vasomotor tone. In this way, the IVC constriction technique provides a more complete description of P/Q relationships than that permitted by simple calculations of pulmonary vascular resistance. We conclude that this technique can be utilized to investigate the effects of other physiological and pharmacological interventions on pulmonary vasomotor tone in conscious dogs.

Animals↗

Anti-HIV inhibitors based on nucleic acids: emergence of aptamers as potent antivirals.

The development of resistance and the inability of currently approved antiretroviral drugs to completely eradicate HIV-1 have led to increased focus on therapies other than small molecules. Although nucleic acid-based intervention requires complex tasks involving intracellular delivery and/or stable expression in target cells, recent advances in gene therapy methods combined with continued progress in stem cell approaches have made nucleic acid-based compounds excellent candidates for effectively inhibiting intracellular targets. Consequently, multiple nucleic acid-based therapies are being developed. These include antisense nucleic acids, peptide nucleic acids and RNA decoys, which can interfere with HIV-1 replication. More recently, RNA interference, which exploits a novel cellular pathway, has been shown to effectively reduce viral titers in cell culture and promises to be a potential candidate for suppressing HIV replication in vivo. A promising candidate in the midst of these emerging approaches is the aptamer approach, which involves the use of a class of small nucleic acid molecules isolated from combinatorial libraries by an in vitro evolution protocol termed SELEX. Aptamers exhibit exquisite specificity, high affinity and the virtual lack of immunogenicity, features that make them exceptionally well-suited to combat HIV without affecting the host. The powerful nature of these specific antagonists of protein function could lead to the development of an effective anti-HIV therapy. Several highly specific, nucleic acid aptamers targeting select HIV proteins have been described. Investigations with anti-HIV RNA aptamers have shown an effective block to viral replication. This review summarizes the existing nucleic-acid based approaches to block HIV replication and attempts to chart the current progress in the development of aptamers against HIV, their use in inhibiting the virus replication, prospects for their use in the clinic and potential drawbacks.

Anti-HIV Agents↗

Transradial approach for coronary procedures: initial experience and results.

BACKGROUND: Due to the recent miniaturization of angioplasty equipment, the transradial approach has gained favor as an alternative catheterization method for coronary procedures. The purpose of this study was to assess the practical clinical application of this method. METHODS: Between June 1997 and February 1998, one operator (MG) attempted the percutaneous transradial approach in 185 consecutive unselected patients with functional radial arch attested using Allen's test. In this series of patients, 102 interventional procedures, balloon angioplasty including stent implantation, were performed with 6F or 7F guiding catheters. RESULTS: Radial arterial punctures for diagnostic procedures were performed in 179 patients with a success rate of 97%. In the six failed transradial accesses, the procedure was performed via the transfemoral route. Balloon angioplasty was performed in 29 patients, 28% (33 lesions), PTCA and stent implantation were performed in 73 patients, 72% (80 lesions). Procedural success was achieved in 100 (98.2%). Two PTCA failed due to the impossibility of crossing a total occlusion. During hospitalization, one patient died of unstable angina and poor left ventricular function 7 days after stenting without stent occlusion at angiography. No major complications related to entry site were observed, and no patients required vascular surgery or blood transfusions. CONCLUSION: This preliminary experience suggests that coronary procedures can be performed safely using the transradial approach. Access-site complications are virtually eliminated and early ambulation may result in a shortened hospital stay and lower hospital costs.

Adult↗

Brain neuronal RNA metabolism during acute soman toxication: effects of antidotal pretreatments.

Effects of various antidotal treatments on neuronal RNA contents and on soman induced RNA and acetylcholinesterase (AChE) depletion were monitored using quantitative cytochemical techniques. In rats only with antidotes, atropine depressed whereas pralidoxime (2-PAM) elevated RNA contents of both caudate and cerebrocortical (Layer V) neurons. Soman produced a virtually complete inhibition of AChE activity and a moderate decline in neuronal RNA contents. Atropine pretreatment partially restored neuronal RNA levels. Atropine + 2-PAM prophylaxis eventuated in a complete restoration of RNA levels but no reactivation of AChE. Addition of physostigmine to the atropine + 2-PAM treatment regimen resulted in appreciable AChE reactivation but reduced RNA levels. The overall data indicate that: (1) soman-induced neuronal RNA depletion can be completely reversed by antidotal pretreatments; (2) no precise relationship exists between the extents of antidote-induced restoration of RNA and AChE levels; and (3) 2-PAM exerts marked effects on the brain neuronal network which are unrelated to AChE reactivation. It is postulated that effects of soman and antidotes on neuronal RNA metabolism may signify alterations in acetylcholine (ACh) sensitivity and that pharmacologic manipulation of ACh responsiveness during organophosphate cholinesterase poisoning may be a mechanism for additional therapeutic intervention.

Acetylcholinesterase↗

Ligands for peroxisome proliferator-activated receptor inhibit monocyte CCR2 expression stimulated by plasma lipoproteins.

Substantial evidence supports a causal role for monocyte chemoattractant protein-1 (MCP-1) and its receptor, CCR2, in the recruitment of monocytes from the circulation into atherosclerotic lesions. MCP-1 is produced and secreted by virtually every cellular component of the vessel wall. It generally is assumed that the magnitude of the monocyte chemotactic activity, which is initiated by the functional activation of CCR2 by MCP-1, is directly proportional to the concentration of the chemoattractant. However, we recently demonstrated that an inflammatory response of monocytes is finely regulated and also depends on the expression levels of CCR2. We identified plasma low-density lipoprotein (LDL) as a positive regulator and showed that it greatly increased monocyte CCR2 gene expression. In contrast, activation of peroxisome proliferator-activated receptor by synthetic ligands or components of oxidized LDL reduces monocyte CCR2 expression and blocks chemotaxis mediated by MCP-1. We hypothesized that the excessive monocyte accumulation in the vessel wall during atherogenesis may result in part from an enhanced chemotactic response. These findings suggest CCR2 gene expression in circulating monocytes as a potential additional target for intervention and prevention of atherosclerosis.

Animals↗

Cumulative pregnancy analysis of one-tube versus two-tube tubal anastomosis.

OBJECTIVE: To determine the prognosis for pregnancy when tubal anastomosis can be performed on only one tube. DESIGN: Prospective collection of demographic and clinical data. SETTING: University medical center. PATIENT(S): One hundred twenty-six women undergoing elective sterilization reversal. INTERVENTION(S): Sterilization reversal was performed by five reproductive endocrine surgeons. In 35 cases, only one tube could be treated surgically. In all cases, this was because of a previous salpingectomy or inadequate distal tubal segment. MAIN OUTCOME MEASURE(S): Cumulative probability of pregnancy in the two groups (one tube or two tubes) was analyzed by survival analysis and logistic regression. Survival curves were compared by log-rank testing. RESULT(S): Comparison of survival curves revealed no difference between the logistic regression curves for probability of conception after anastomosis of one tube versus two tubes. Logistic regression revealed a similar cumulative probability of conception with a two-tube (0.76) and a one-tube anastomosis (0.63). The monthly fecundity rates were 0.032 and 0.034 for a two-tube and one-tube anastomosis, respectively. There were no differences between the groups with respect to age, gravidity, or parity. Virtually all pregnancies occurred within 2 years of surgery. CONCLUSION(S): The prognosis for conception after one-tube anastomosis was the same as for two-tube anastomosis.

Fallopian Tubes↗

The effects of severe behavior problems in children on the teaching behavior of adults.

Applied behavior analysts have focused on how adults can influence the problem behavior of children using a variety of behavior modification strategies. A related question, virtually unexplored, is how the behavior problems of children influence adults. This child-effects concept was explored empirically in a study involving 12 adults who were asked to teach four pairs of children in which one member of the pair exhibited problem behavior and the other typically did not. Results demonstrated that problem children displayed tantrums, aggression, and self-injury contingent on adult instructional attempts but not at other times, whereas nonproblem children showed little or no problem behavior at any time. Importantly, from a child-effects perspective, adults engaged in teaching activities with nonproblem children more often than with problem children. Also, when an adult worked with a problem child, the breadth of instruction was more limited and typically involved those tasks associated with lower rates of behavior problems. The implications of these results are discussed with respect to theories of escape behavior, current assessment practices, and intervention issues related to maintenance. The existence of child effects suggests that problem behavior may be better understood when it is conceptualized as involving a process of reciprocal influence between adult and child.

Adult↗

Prevention of stone formation and bone loss in absorptive hypercalciuria by combined dietary and pharmacological interventions.

PURPOSE: We determined whether dietary restriction of calcium and oxalate, combined with thiazide and potassium citrate treatment, would prevent stone formation and avert bone loss in 18 men and 10 women with type I absorptive hypercalciuria. MATERIALS AND METHODS: Patients were treated with thiazide (20) or indapamide (8) and potassium citrate (average dose 35 mEq. daily) for 1 to 11 years (mean 3.7) while maintained on low calcium oxalate diet. Serum and urinary chemistry studies and bone mineral density were measured at baseline and at the end of treatment. New stones formed were quantitated during 3 years before and during treatment. RESULTS: During treatment urinary calcium significantly decreased (346 +/- 85 to 248 +/- 79 mg. daily, p <0.001) but urinary oxalate did not change. Urinary pH and citrate significantly increased, and urinary saturation of calcium oxalate significantly decreased by 46%. Stone formation rate decreased significantly from 2.94 to 0.05 per year (p <0.001). L2-L4 bone mineral density increased significantly by 5.7% compared to normal peak value, and by 7.1% compared with normal age and gender matched value. Femoral neck bone mineral density also increased significantly. CONCLUSIONS: Dietary restriction of calcium and oxalate, combined with thiazide and potassium citrate, satisfactorily controlled hypercalciuria, prevented the secondary increase in urinary oxalate, reduced urinary saturation of calcium oxalate, virtually eliminated recurrent stone formation, and increased bone density of the spine and femoral neck. Thus, this dietary pharmacological program controlled stone formation as well as bone loss that often accompany type 1 absorptive hypercalciuria.

Absorption↗

Stent-assisted coiling of intracranial aneurysms aided by virtual parent artery reconstruction.

The availability of stents designed specifically for use in the intracranial vasculature has increased the use of stent-assisted coiling for treatment of wide-necked and complex intracranial aneurysms. We present a technique for pretreatment planning and visualization of a virtual stent within the parent artery by using a virtual reconstruction of the parent artery across the aneurysm neck. As illustrated by 2 clinical examples, this method provides information not otherwise available regarding the location of portions of the stent that are not visible on fluoroscopy. During treatment, this information enhances the ability to determine the location of coils in relation to the stent boundaries and should thereby improve the ability to avoid parent artery compromise.

Angiography, Digital Subtraction↗