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PubMed2001

The epidemiology of end-stage renal disease in the Baltic countries: an evolving picture.

INTRODUCTION: The epidemiology of end-stage renal disease (ESRD) and renal replacement therapy (RRT) is under continuous evolution all over the world. Of particular interest is the development of RRT in the countries of the former Soviet bloc which underwent great political and socio-economical changes in the last decade. We report here the epidemiological analysis of ESRD and RRT in the three Baltic countries: Lithuania, Estonia, Latvia. Subjects and methods. This epidemiological report is based on data from centre questionnaires which were collected from 1996 onwards, with a response rate of 98-99%. RESULTS: The prevalence/incidence of RRT patients in 1999 were 213/99.5 p.m.p. in Lithuania, 186/45.5 p.m.p. in Estonia and 172/55.8 p.m.p. in Latvia. Haemodialysis (HD) was the most common RRT modality in Lithuania (60% of prevalent patients), but not in Estonia (29%), while in Latvia it was nearly as common as renal transplantation (45 and 46%, respectively). Home HD was not performed. The proportion treated by peritoneal dialysis (PD) was very low in Lithuania (4% of RRT patients), while the percentage was higher in Latvia (9%) and Estonia (20.4%). The percentage of patients on RRT treated by renal transplantation was high throughout, representing the main modality of treatment in Estonia (50.5% of RRT prevalent patients, 94 p.m.p.) and in Latvia (46%, 79 p.m.p.) and being high in Lithuania (36%, 77 p.m.p.). The main renal diseases leading to ESRD were glomerulonephritis, pyelonephritis and diabetes. CONCLUSION: The epidemiology of RRT in the Baltic countries is undergoing rapid changes. Transplantation has reached an impressive level. A high percentage of RRT patients live with a functioning graft.

Estonia↗
PubMed2002

The epidemiology of end-stage renal disease in Iran in an international perspective.

INTRODUCTION: The epidemiology of end-stage renal disease (ESRD) and renal replacement therapy (RRT) is under continuous evolution all over the world. We report here the epidemiological analysis of ESRD and RRT in Iran and discuss it against the background of the international situation. METHODS: This epidemiological report is based on data from centre questionnaires which were collected in Iran from 1997 onwards, with a response rate of 100%. RESULTS: The prevalence/incidence of RRT patients were 238/49.9 p.m.p. in the year 2000. Haemodialysis and kidney transplantation were the most common RRT modalities, accounting for 53.7% and 45.5% of prevalent RRT patients, respectively. The proportion treated by peritoneal dialysis was very low (<1%). Home haemodialysis was not performed. The majority of haemodialysis centres used synthetic membranes (70%) and 100% of the sessions were performed using acetate as a buffer; 42.5% of haemodialysis patients were treated with a twice-weekly regimen, whilst 49.6% were on the standard thrice-weekly regimen. The majority of RRT patients in Iran were young to middle aged. The great majority of renal allografts came from living donors (mainly unrelated to recipients). The main renal diseases leading to ESRD were diabetes and hypertension. The third most common category was "cause unknown". CONCLUSION: The epidemiology of RRT in Iran is characterized by: (i) young patient age (younger than the international average); (ii) high proportion of patients receiving renal allograft; (iii) use of living-unrelated donors as the major source of renal allografts.

Adolescent↗
PubMed1987

Combined therapy as an alternative to exenteration for locally advanced vulvovaginal cancer. II. Results, complications, and dosimetric and surgical considerations.

We have introduced a therapeutic alternative to exenteration for locally advanced vulvovaginal cancer using surgery for the vulvar (external genital) phase of this disease presentation, combined with radiotherapy for the internal genital phase (with adequate overlap of fields to protect surgical margins). The rationale is that this approach treats the cancer and its dual regional spread patterns, while at the same time preserving the bladder and/or rectum, and should be associated with less morbidity and mortality than exenterative surgery. This report updates our experience with a total of 48 treated cases (37 primary cases and 11 cases of recurrent disease). Of the 37 primary cases, 20 were FIGO stage III, 4 were FIGO stage IV, and 3 other cases represented "field" cancers involving vulva and/or cervix and/or vagina. Utilizing a Life Table analysis, the 5-year survival for the primary cases was 75.6%. Published FIGO survival for stage III is 32% and for stage IV 10.5%. Life Table analysis projects a 62.6% survival for recurrent cases and an overall 72% 5-year survival for all 48 cases treated. With 48 patients treated, 48 bladders and 48 rectums were at risk for surgical removal had exenteration been employed. One patient had a total pelvic exenteration for local failure, and one had a posterior exenteration for local failure. One bladder and one rectum were lost to permanent diversion because of radiation injury. Thus, 5 of these major viscera were lost of the 96 total, and 91 (94.8%) were retained. Radiation therapy and surgical details have been reviewed relevant to local control and local failure and complications. The continuing evolution of treatment modifications of all modalities will be discussed. The apparent advantages of this combined therapeutic approach over exenterative surgery include high probability of bladder and/or rectal preservation, low primary mortality, low treatment morbidity, and very good results in cancer control.

Brachytherapy↗
PubMed1981

Medical technology and academic medicine: the doctor-producers' dilemma.

Diagnostic technologies differ from therapeutic technologies in several ways. Use of a diagnostic technologies is increasing faster than overall medical care. New diagnostic technologies tend to be additive and often have multiple uses. In evaluating their benefits, one should assess marginal, not absolute, utilities and measure clinical as well as financial costs. Although the use of therapeutic technologies is more circumscribed, these technologies tend to be in continuous evolution, especially when new. Comparative evaluations of therapeutic technologies are expensive and time-consuming. Pro-technology reimbursement biases may be the most important of the many factors promoting technology use. Academic medical centers, which have become increasingly clinically specialized, must now compete with their own graduates for specialty patients. At the same time they are urged to respond to contradictory national health policies that favor production of more generalists under a pro-specialty reimbursement system. Suggestions for more appropriate technology use should cover multiple approaches, including the changing of current financial incentives and the use of technology assessment to improve quality of care and education.

Academic Medical Centers↗
PubMed1999

"A world of knowledge at your fingertips": the promise, reality, and future directions of on-line information retrieval.

Medical knowledge resources are increasingly available in electronic form, particularly on the World Wide Web. The promise of this medium is that it offers a vast "world of knowledge at your fingertips." The reality, however, is somewhat different, as information systems are not well integrated into clinical practice, prove difficult to find specific information in, and contain content of varying quality. The continued evolution of the medium in the future should, however, be beneficial, as synthesized evidence-based resources become available and these resources are integrated into electronic medical record systems.

Education, Medical↗
PubMed2006

Academic research record-keeping: best practices for individuals, group leaders, and institutions.

During the last half of the 20th century, social and technological changes in academic research groups have challenged traditional research record-keeping practices, making them either insufficient or obsolete. New practices have developed but standards (best practices) are still evolving. Based on the authors' review and analysis of a number of sources, they present a set of systematically compiled best practices for research record-keeping for academic research groups. These best practices were developed as an adjunct to a research project on research ethics aimed at examining the actual research record-keeping practices of active academic scientists and their impact on research misconduct inquiries. The best practices differentiate and provide separate standards for three different levels within the university: the individual researcher, the research group leader, and the department/institution. They were developed using a combination of literature reviews, surveys of university integrity officials, focus groups of active researchers, and inspection of university policies on research record-keeping. The authors believe these best practices constitute a ''snapshot'' of the current normative standards for research records within the academic research community. They are offered as ethical and practical guidelines subject to continuing evolution and not as absolute rules. They may be especially useful in training the next generation of researchers.

Benchmarking↗
PubMed2000

Molecular evidence for drug-induced compartmentalization of HIV-1 quasispecies in a patient with periodic changes to HAART.

OBJECTIVE: To perform molecular analysis of the predominant viral populations and drug-resistance mutations from plasma and peripheral blood mononuclear cell (PBMC) compartments over time from an HIV infected patient, who experienced virological failure while on different HAART regimens. MATERIALS AND METHODS: In a longitudinal study proviral and plasma HIV-1 sequences were amplified in the pol, protease and env genes and were sequenced directly and analysed phylogenetically. Virus was recovered from time points corresponding to viral load peaks using co-culturing techniques. The periodic failure of different highly active antiretroviral therapy (HAART) regimens was analysed sequencing. RESULTS: Longitudinal follow-up studies revealed four inflection peaks of plasma viraemia associated with the recovery of culturable virus in vitro, which indicated failure of the concurrent HAART regimen. Molecular analysis of viral strains revealed evidence of continual evolution and compartmentalization of drug-resistance mutants/quasispecies between plasma and PBMC, with the widest spectrum of mutations isolated from plasma. Importantly, these data show the periodic appearance and clearance of drug-resistance mutants concomitant with the introduction and withdrawal of zidovudine over time. CONCLUSION: This report is unique in showing drug-induced compartmentalization of viral quasispecies under the control of different HAART regimens in both plasma and PBMC. Introduction and withdrawal of zidovudine from the HAART regimen had direct bearing on the appearance and disappearance of specific zidovudine drug-resistance mutations in plasma-derived virus. This data has important implications for the management of HIV-infected patients with poor compliance with certain HAART regimens, and also in predicting the late emergence of drug-resistance mutations via the latent integrated provirus.

Adult↗
PubMed1998

Characterization of middle cerebral artery occlusion infarct development in the rat using fast nuclear magnetic resonance proton spectroscopic imaging and diffusion-weighted imaging.

A nuclear magnetic resonance study of the middle cerebral artery occlusion in the rat is presented. Experiments were performed on seven animals before and after occlusion, which occurred in situ. The emphasis in this study was on evaluating rapid proton spectroscopic imaging. Data were acquired with experimental durations of between 4 and 15 minutes for a 32 by 32 spatial matrix, with 64 spectroscopic data points per spatial element. The spectroscopic data were interleaved with diffusion-weighted nuclear magnetic resonance water images of the same slice. The study was terminated at about 6 hours after occlusion. The brains were then frozen in liquid nitrogen for biochemical imaging. The results showed that the signal from N-acetyl aspartate decreased and that of lactate increased within the infarcted region. The temporal course of these intensity changes varied between animals. Nineteen cortical spreading depressions (CSD) were observed by electrophysiologic monitoring during the experiments. Of these, 11 could be unambiguously detected in the lactate images, and a further 3 were on the threshold of detectability. As only a single slice could be examined, it is possible that the centers of depression for the remaining 6 CSD were outside the slice. To the authors' knowledge, this is the first report of the measurement of CSD using proton spectroscopic imaging. Thus, it is shown that this method is valuable not only in following the continuous evolution of proton metabolites with a good spatial and temporal resolution, but also in observing transient phenomena which are believed to play an important role in the expansion of the infarcted territory.

Animals↗
PubMed1999

The future of gastroenterology in the era of managed care.

Specialty practice in general, and gastroenterology in particular, is undergoing significant transformation as we head into the new millennium. Gastroenterologists will need to adapt to the continued evolution and consolidation of managed care. Among other issues, gastroenterologists will need strategies for dealing with pricing pressures, changing technology, increased consumerism, a perceived specialist oversupply, and a rapidly aging population. These and other developments will drive a myriad of physician responses in an effort to confront changing practice realities.

Delivery of Health Care, Integrated↗
PubMed1998

Computer-assisted three-dimensional reconstruction of head and neck tumors.

OBJECTIVE: Because head and neck tumors reside in a complex area, having a three-dimensional (3-D) model of the patient's unique anatomical features may assist in the delineation of pathology. The authors describe a new computer technique of 3-D anatomical reconstruction from two-dimensional computed tomography (CT) and magnetic resonance (MR) data and discuss how it represents a step forward in the continuing evolution of 3-D imaging. STUDY DESIGN: The authors selected three patients with solitary head and neck tumors and reconstructed their anatomy in a 3-D format for study. The tumors represented locations in the nose and central skull base (patient 1), temporal bone (patient 2), and neck (patient 3). MATERIALS AND METHODS: MR and CT images from the individual patients were electronically transferred to workstations in the Surgical Planning Laboratory of the authors' institution. Registration (or fusion) was carried out between the MR and CT images. The desired anatomic components underwent segmentation (identification and isolation). Assembly of the segmented images was performed and the resulting structures were integrated to produce a 3-D model. RESULTS: 3-D models of the following were constructed and displayed in an interactive format on high-capacity computer workstations: 1) a skull base sarcoma with extension into the nasopharynx and nose; 2) an acoustic neuroma with internal auditory canal involvement; and 3) a metastatic recurrence of a tongue base squamous cell carcinoma in the posterior triangle of the right side of the neck with extension to the skull base. CONCLUSION: The authors' Surgical Planning Laboratory has developed a 3-D reconstruction technique that has several new features. The models provided a very good 3-D interactive representation of the tumors and patient anatomy. The need now exists to develop this method of 3-D reconstruction of head and neck tumors for potential applications in treatment, research, and medical education.

Adult↗
PubMed2003

Percutaneous nephrolithotomy: an update.

PURPOSE OF REVIEW: Percutaneous nephrolithotomy has undergone an evolution in technique and in equipment since its introduction in the late 1970s. This evolution continues today and is evidenced by the numerous publications about the technique. This review summarizes some of the important articles over the past year. RECENT FINDINGS: Although ureteroscopy and shock wave lithotripsy predominate in the treatment of urolithiasis, percutaneous nephrolithotomy continues to play an important role. Percutaneous nephrolithotomy is advantageous as it causes minimal renal injury and maximizes stone clearance, especially in patients with complex stone disease. Although nephrostomy drainage tubes have always been placed after percutaneous nephrolithotomy, there may be specific indications for tubeless percutaneous nephrolithotomy. SUMMARY: Percutaneous nephrolithotomy continues to be an important part of the urologist's armamentarium. Recent studies have redefined the role of percutaneous nephrolithotomy and future studies will further delineate the importance of this procedure in the treatment of urolithiasis.

Clinical Trials as Topic↗
PubMed1988

Red cell size heterogeneity during ontogeny.

To determine the manner in which erythrocyte changes occur during ontogeny, several red cell parameters were analyzed in fetuses, newborn infants, children, and adults. Although mean cell volume (MCV) and hemoglobin F (HbF) levels decreased as expected during in utero development, the coefficient of variation of red cell size (%CV), or red cell distribution width (RDW), increased from fetuses to newborn infants. In normal adults, the %CV was 15 (RDW was 13). The %CV in fetuses at 18-24 weeks gestation was 18, and it was 21 at term birth. High values for %CV or RDW indicate significant anisocytosis. Erythropoiesis at the time of birth is not a steady-state condition. Erythrocytes of a wide variety of sizes are present, with the appearance of new small cells on a background of older, larger red cells. This increased anisocytosis suggests that these new erythrocytes do not appear to be due to a smooth, continuous evolution of red cell size, but rather to discrete, perhaps clonal, changes.

Adolescent↗
PubMed2006

The evolving structure of orthopaedic residency education.

Orthopaedic residency has undergone continual evolution since the early 1900s. Training has evolved from a preceptorship to a highly evolved and structured educational system which largely standardizes training throughout the United States. Approval and accreditation of training programs, as well as content, is now overseen by a hierarchical group of organizations with representations from a variety of medical societies and boards. The evolving process has served the public well, providing competent care of the musculoskeletal system.

History, 20th Century↗
PubMed2006

Echocardiographic measures of diastolic function in pediatric heart disease.

PURPOSE OF REVIEW: The past year has seen a continued evolution in the echocardiographic assessment of diastolic function in children. This paper reviews published studies from the past year that have helped characterize diastolic function using echocardiography in children. RECENT FINDINGS: Characterization of diastolic function using Doppler and Doppler tissue imaging in the normal infant and child was a primary focus of pediatric echocardiographic investigation. These technologies appear to hold significant promise as tools to improve understanding of diastolic function in the normal child as the heart matures. Diastolic function in children with congenital heart disease has also been better characterized using these tools, specifically in patients with atrial septal defects, tetralogy of Fallot, single ventricle physiology, and following cardiac transplantation. Finally, diastolic function in acquired heart disease or with systemic disease in the child has been evaluated using echocardiography, with recent reports describing findings in children with dilated cardiomyopathy, chronic renal disease, obesity, type I diabetes, juvenile rheumatoid arthritis, obstructive sleep apnea, and after anthracycline exposure for childhood cancer. SUMMARY: Pediatric echocardiography has clearly become the primary tool for describing and characterizing diastolic function in infants and children both with and without heart disease. It is becoming an important noninvasive diastolic monitoring tool that allows serial assessment of pathologic diastolic disease in both primary myocardial and systemic disease states.

Anthracyclines↗
PubMed2005

Community-acquired pneumonia in children.

PURPOSE OF REVIEW: This review highlights recent developments in the diagnosis, etiology, therapy, and prevention of community-acquired pneumonia in children. RECENT FINDINGS: Sensitive new diagnostic methods have increased the detection rate of the causative agent up to 94%. Streptococcus pneumoniae is the most prevalent bacterial pathogen in all ages. Polymerase chain reaction is a rapid and sensitive method for the detection of Chlamydia pneumoniae and Mycoplasma pneumoniae, which have gained greater importance in recent years. During the period covered by this review, two new agents causing pneumonia were extensively studied. Human metapneumonovirus detected in young children is a leading cause of respiratory disease during the first years of life. A novel coronavirus was identified as the causative agent of severe respiratory syndrome, a new respiratory illness that affects adults and children. One multicenter trial concluded that nonsevere pneumonia can be treated with a short course of oral amoxicillin and a multicenter international study showed that children with severe pneumonia have similar outcomes whether treated with oral amoxicillin or parenteral penicillin, but more data are needed to demonstrate the safety and efficacy of such regimens. SUMMARY: The continued evolution of bacterial resistance highlights the need for appropriate use of antibacterials. Improved diagnostic techniques will aid the treatment of children with community-acquired pneumonia. Aggressive vaccination with the pneumococcal conjugate vaccine and other available vaccines as well as the development of new vaccines will aid the prevention of respiratory disease in children.

Adolescent↗
PubMed2005

Computer-assisted laparoscopic repair of "upside-down" stomach with the Da Vinci system.

Recently introduced telerobotic surgical systems attempt to elude the inherent limitations of traditional laparoscopic surgery. Four patients (3 male, 1 female) with mixed hiatal and paraesophageal hernias with fixed intrathoracic partial or complete displacement of the stomach were operatively treated using the Da Vinci robotic system. Tissue dissection, hiatoplasty, and anterior hemifundoplication (Dor) were performed with the telerobotic system. There were no surgical complications. The system broke down in the fourth patient due to a software defect. Advantages were seen in terms of the intrathoracic dissection of displaced stomach through a narrow hiatus, intracorporeal suturing due to 6 degrees of freedom plus grasping. At the moment, lack of the appropriate robotic instruments for abdominal surgery as well as the enormous functional cost of the robotic system are considered to be the most significant current impediment to the adoption of robotic abdominal surgery. The continuous evolution and upgrade of the system is quite promising so far. Telerobotic-assisted hiatal hernia operation is feasible with many advantages compared with the traditional laparoscopic approach, especially during the dissection in the mediastinum in patients with intrathoracic stomach. A prospective, randomized trial will be performed later to evaluate the advantages and limitations of robotic compared with traditional laparoscopy. Technological evolution will perhaps diminish the current problems and the cost associated with robotic surgery.

Aged↗
PubMed2007

New monitoring software for larger clinical application of brachial artery flow-mediated vasodilatation measurements.

BACKGROUND: The reproducibility of brachial artery flow-mediated vasodilatation (FMD) is limited by the operator dependence of most measurement methods. METHODS: A new automated computerized analysis of brachial artery ultrasound scan providing a continuous evolution of the diameter during acute hyperemia, reactive to short hyperemia of the forearm and hand, was tested in 10 normal volunteers and 26 asymptomatic patients with cardiovascular risk factors such as hypertension, hypercholesterolemia, heavy smoking, history of premature coronary heart disease and the metabolic syndrome. FMD was the percentage of the maximum hyperemic diastolic diameter from baseline. Within-reading variations in FMD and diameters were assessed by reading one scan from the same subject twice by two observers. The within-subject variability of FMD was assessed by analysing two repeated measurements in the same subject by the same operator 1 h, 1 week or 1 month apart. RESULTS: Coefficients of variation (CV) of repeated FMD readings were 7.5% in normal volunteers and 6.9% in patients with risk factors. CV of repeated FMD measurements 1 h apart were 7.8% in normal volunteers and 16.5% in patients with risk factors. In normal volunteers, CV of repeated FMD measurements 1 week apart was 9.6%, and in patients with risk factors CV of repeated FMD measurement 1 month apart was 18.1%. CONCLUSION: This method overcomes the variability of FMD measurement seen with conventional manual analysis in normal volunteers, and to a lesser extent in patients with major cardiovascular risk factors, thus supporting its clinical applicability to patients with disease conditions.

Adult↗