bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Oral Effects of Osteoporosis
Authors: Krall Elizabeth A. 
Published: March 2003

AbstractA majority of elderly persons have lost one or more teeth, a condition that adversely affects the ability to maintain an adequate nutritional intake. Presence of a systemic disease, such as osteoporosis, is one of several factors thought to lead to tooth loss in older adults. Many studies with elderly populations have shown associations between low bone mineral density and number of missing teeth, increased levels of alveolar bone loss, and clinical measures of periodontal disease. However, the clinical significance of systemic bone loss density in contributing to the loss of oral bone and teeth is unknown. Future studies will determine if nutritional interventions could play a role in preventing tooth loss. Until there is more evidence, patients should follow the current recommendations for calcium and vitamin D intakes to ensure overall health.
Evaluation and Treatment of Low Bone Density in Anorexia Nervosa
Authors: Misra Madhusmita , Klibanski Anne 
Published: March 2003

AbstractThe prevalence of anorexia nervosa has increased in recent years, and a large proportion of adults as well as adolescents with this disorder have low bone density and, therefore, an increased risk of fractures. Anorexia nervosa often begins during adolescence, when peak bone mass is accumulated, resulting in significant deficits in bone mass accrual. Therefore, it is important to determine bone mineral density in adolescent and adult women who have this disorder, and to improve or at least stabilize bone metabolism in those with low bone mass. To do this, it is necessary to understand the mechanisms underlying low bone density in anorexia nervosa. This article discusses current concepts related to bone loss associated with anorexia nervosa, including how to prevent it.
Establishing an Effective Framework for Physical Activity Counseling in Primary Care Settings
Authors: Blackburn, MALD David G. 
Published: March 2003

AbstractThis article examines the role of the primary care physician in providing physical activity counseling and proposes a framework for maximizing the effectiveness of this activity. Many studies have been conducted to evaluate the effectiveness of physical activity counseling in the primary care setting. Unfortunately, the results of most of these studies have not been encouraging as there has not been compelling evidence that brief physical activity counseling for the general population results in long‐term changes in physical activity behaviors. In contrast, the evidence of health improvements in patients who are successful in achieving levels of physical activity consistent with the Surgeon General's recommendations is compelling and should serve as the source of motivation as we seek more effective paradigms for physical activity counseling. The PACE (Patient‐Centered Assessment and Counseling for Exercise and Nutrition) Program is presented as an evidenced‐based and effective framework for effective physical activity counseling. By adopting a patient‐centered approach to counseling and by tailoring the message to the readiness of the patient to take action, it is possible to engage in physical activity counseling in a cost‐ and time‐effective manner. This article provides specific counseling strategies for addressing patients at various stages of readiness to engage in behavior change regarding physical activity.
Apoptosis in regenerating and denervated, nonregenerating urodele forelimbs
Authors: Mescher Anthony L , White Gary W , Brokaw James J 
Published: March 2003

Denervated limbs of larval salamanders fail to regenerate if amputated and, unlike adult limbs, undergo regression. The cellular basis of the tissue loss is poorly understood. We used TUNEL staining of larval axolotl limbs fixed and sectioned at intervals after bilateral amputation and unilateral denervation to investigate the role of apoptosis during normal limb regeneration and denervated limb regression. In the first week after amputation a small percentage of apoptotic cells was found in both innervated and denervated limbs. During the second week the apoptotic index remained low in the mitotically active mesenchymal cells of the regenerating limbs, but increased twofold in the nondividing, dedifferentiated cells of the regressing limbs. TUNEL‐positive cells resembling apoptotic bodies were restricted primarily to the dedifferentiated area beneath the wound epithelium, but were also present within the wound epithelium itself. Macrophages were identified immunohistochemically and were also found in increased numbers in distal areas of the denervated regressing limbs. The results suggest a role for apoptosis in the early phase of normal regeneration and indicate that denervated limb regression involves an increased rate of apoptosis and removal of apoptotic bodies by macrophages and the wound epithelium.(WOUND REP REG 2000;8:110–116)
K‐rich fluid metasomatism at high‐pressure metamorphic conditions: Lawsonite decomposition in rodingitized ultramafite of the Maksyutovo Complex, Southern Urals (Russia)
Authors: Schulte B. , Sindern S. 
Published: March 2003

AbstractFine grained rodingite‐like rocks containing epidote, clinozoisite, garnet, chlorite, phengite and titanite occur within antigorite serpentinite boudins from the high‐pressure metamorphic Maksyutovo Complex in the Southern Urals. Pseudomorphs after lawsonite, resorption of garnet by chlorite and phengite and stoichiometry suggest the reaction lawsonite + garnet + K‐bearing fluid → clinozoisite + chlorite + phengite, and define a relic assemblage of lawsonite + garnet + chlorite + titanite ± epidote as well as a later post‐lawsonite assemblage of clinozoisite + phengite + chlorite + titanite. The reaction lawsonite + titanite → clinozoisite + rutile + pyrophyllite + H2O delimits the maximum stability of former lawsonite + titanite to pressures >13 kbar. P–T conditions of 18–21 kbar/520–540 °C result, if the average chlorite, Mg‐rich garnet rim and average epidote compositions are used as equilibrium compositions of the former lawsonite assemblage. These estimates indicate a similar depth of formation but lower temperatures to those recorded in nearby eclogites. The metamorphic conditions of the lawsonite assemblage are considerably higher than previously suggested and, together with published structural data, support a model in which a normal fault within the Maksyutovo complex acted as the major transport plane of eclogite exhumation.The maximum Si content of phengite and minimum Fe content in clinozoisite constrain the metamorphic conditions of the later pseudomorph assemblage to be >4.5 kbar and <440 °C. Rb–Sr isotopic dating of the pseudomorph assemblage results in a formation age of 339 ± 6 and 338 ± 5 Ma, respectively. These results support the recent exhumation models for this complex.
ACID‐BASE IN RENAL FAILURE: What Have Isotope Studies in Humans Told Us About the Nutritional Effects of Acidosis in Dialysis?
Authors: Louden Jonathan D. , Roberts Russell G. , Goodship Timothy H. J. 
Published: March 2003

ABSTRACTIn order to understand how acidosis might predispose to loss of lean body mass it is important to recognise that body protein is in a dynamic state with a daily turnover of approximately 300 g of protein in a 60 kg man. This is significantly greater than the daily protein intake at a level of 1 g · kg‐1· day‐1. Loss of lean body mass occurs when the balance between whole body protein synthesis and breakdown is negative. Measurement of whole body protein turnover is possible using either boluses or primed constant infusions of isotopically labelled amino acids. Previously, a variety of in vitro and in vivo animal studies have shown that acidosis increases protein degradation and amino acid oxidation. Several research groups including our own have used amino acid tracer techniques to examine whether protein degradation is increased in vivo in human subjects with acidosis and chronic renal failure. The results from these studies have shown a remarkable concordance with increased protein degradation in all groups of patients studied. However, the results for protein synthesis have been more difficult to interpret, with only a few studies directly measuring the effects of acidosis on amino acid incorporation into protein.
Are Parathyroidectomies Still Appropriate in Chronic Dialysis Patients?
Authors: Cunningham John 
Published: March 2003

ABSTRACTThe uremic milieu generates chronic stimulatory input to the parathyroid glands, which is mediated principally by low calcium, high phosphate and low calcitriol, and results in increased parathyroid hormone (PTH) synthesis and release and an increase in parathyroid mitotic activity with the development of monoclonal areas of nodular hyperplasia. Such glands do not fully express the machinery required to mediate the suppressive inputs to the parathyroids; the extracellular calcium receptor (CaR) and the vitamin D receptor (VDR) are both downregulated. In most of these patients ablation, by parathyroidectomy or ethanol injection, provides the only means of correcting the hyperparathyroidism; apoptosis in parathyroid cells is negligible and clinically irrelevant. In practice, surgery is often delayed by a doomed and ultimately futile attempt to effect control by medical means. Better predictors of the likely success or failure of optimal non surgical management are needed. Gland size exceeding 1 cm3 and elevated PTH despite hypercalcemia (implying loss of suppressibility by calcium), in the presence of good phosphate control and adequate calcitriol provision point strongly to eventual failure of medical treatment and the need for parathyroid ablation. Parathyroidectomy, usually subtotal, remains the standard management, with ultrasound guided injection of ethanol or calcitriol showing promise in some centers. The above scenario is unlikely to be changed greatly by the new emerging vitamin D metabolites, but calcimimetic agents may well increase the scope of non surgical management.
Improvement in Hemodialysis Vascular Access Outcomes in a Dedicated Access Center
Authors: Arnold W. Perry 
Published: March 2003

ABSTRACTThere are more than 300,000 end‐stage renal disease (ESRD) patients in the United States, with those on hemodialysis requiring vascular access for dialysis treatment. According to the 1999 annual report of the U.S. Renal Data System (USRDS), the leading cause of morbidity in this patient population is related to vascular access placement and the resultant complications. Vascular access procedures account for more than 10% of the annual ESRD budget and are conservatively estimated at $1 billion annually. The impact of dysfunctional vascular access on physician time, health care resources, and patient quality of life is profound. In 1997 I opened a freestanding, dedicated access center for the diagnosis and treatment of access‐related disorders. This article summarizes the experience of this center. In our freestanding dialysis access center, a large referral base has been established consisting of 30 dialysis centers with approximately 2000 patients. During the 27 months from October 1997 to December 1999, 1087 patients were treated. These patients received 2862 access procedures (2.6 procedures/patient). Annualized, this gives a dysfunction rate of 1.15 episodes/patient/year at risk. Endovascular declotting procedures were performed 1282 times (45%) with a success rate (defined as one uneventful hemodialysis following the procedure) of 93% (1187/1282). Prospective angiography followed by percutaneous transluminal angioplasty was performed 703 times (24%). This procedure was successful 695 times for a success rate of 99%. There were 644 (23%) catheter procedures performed consisting of catheter placements, catheter exchanges through new or old tracts, and catheter removals. The success rate for catheter procedures was 99.1%. Complication rates were extremely low, both for major and minor complications, exceeding all published standards. Hemodialysis vascular access can be optimized in a freestanding, focused, outcomes‐driven outpatient access center. Outcomes can meet or exceed the National Kidney Foundation Dialysis Outcomes Quality Initiative (NKF‐DOQI) guidelines for vascular access while at the same time providing the patient with an outpatient procedure and the referring dialysis unit and nephrologist with an efficient, effective mode of patient care.
Modalities for the Removal of β2‐Microglobulin from Blood
Authors: Ameer Guillermo A. 
Published: March 2003

ABSTRACTThe long‐term accumulation of β2‐microglobulin (β2M) in patients with kidney failure results in a debilitating condition referred to as dialysis‐related amyloidosis (DRA). There have been few methods specifically designed to remove the large quantities of β2M that are produced by the body. This article briefly reviews current modalities and concepts for the removal of β2M from blood. The various approaches are classified according to the mechanism of β2M clearance. The potential application of immunoadsorption, a biologically specific approach to remove macromolecules, in the treatment and understanding of DRA is discussed.
Dynamic of β2‐Microglobulin Fibril Formation and Reabsorption: The Role of Proteolysis
Authors: Bellotti Vittorio , Gallieni Maurizio , Giorgetti Sofia , Brancaccio Diego 
Published: March 2003

ABSTRACTDialysis‐related amyloidosis (DRA) is caused by the deposition, in target tissues, of β2‐microglobulin (β2M) in fibrillar conformation. Several reports indicate that fibrillar β2M is chemically heterogeneous and such heterogeneity is partially related to the presence of truncated species of the protein. In association with the full‐length species, a β2M isoform lacking six N‐terminal residues is present in all the samples of our collection of ex vivo fibrils. The pattern of proteolytic cleavage in amyloidosis and in other diseases is completely different, as demonstrated by the absence in fibrillar β2M of the cleavage at lysine 58, which is contrary to that described in rheumatoid arthritis and other diseases. The role of limited proteolysis of β2M in the pathogenesis of the disease is uncertain. However, we have shown that the apparently minor modification of the intact protein, such as the removal of N‐terminal hexapeptide, is capable of dramatically affecting its stability, protection from proteolytic digestion, and enhance its capacity to make in vitro amyloid fibrils. The structure, folding dynamic, and function of the truncated species of β2M, peculiar of DRA, could shed new light on the mechanism of β2M fibril formation and reabsorption.
Dialysis‐Related Amyloidosis: History and Clinical Manifestations
Authors: Danesh Farhad , Ho Louisa T. 
Published: March 2003

ABSTRACTDialysis‐related amyloidosis (DRA) or β2‐microglobulin amyloidosis (Aβ2M) is a unique type of amyloidosis that has been described in individuals with both long‐standing chronic renal disease and end‐stage renal disease (ESRD). It has been associated with serious complications that significantly add to the morbidity of long‐term dialysis patients. The deposition of β2M in amyloid fibrils in various joint and osteoarticular surfaces leads to the clinical complaints and findings typical of this disorder. However, a visceral form with systemic organ involvement has also been described. Despite advances in the understanding of this disorder and in the delivery of dialysis, the ability to alter the incidence of DRA and its course remains uncertain.
Protein Intake in Patients with Renal Failure: Comments on the Current NKF‐DOQI Guidelines for Nutrition in Chronic Renal Failure
Authors: Lim Victoria S. , Flanigan Michael J. 
Published: March 2003

ABSTRACTThe National Kidney Foundation Clinical Practice Dialysis Outcomes Quality Initiative (DOQI) guidelines recently recommended dietary protein intake for patients with chronic renal failure as follows: predialysis patients should receive 0.60 g/kg/day of protein and increase intake to 0.75 g/kg/day for subjects who cannot follow such a diet. For stable maintenance hemodialysis patients, the recommended protein intake is 1.2 g/kg/day, and for chronic peritoneal dialysis patients, 1.2–1.3 g/kg/day. We differ with these recommendations and believe that a dietary protein intake of 0.8 g/kg/day is appropriate for the predialysis population; an intake of 0.9–1.0 g/kg/day and 1.0–1.1 g/kg/day for maintenance hemodialysis patients and peritoneal dialysis patients, respectively, should be adequate. The rationale and the evidence supporting our arguments are outlined and discussed.
Imaging in the Dialysis Patient: Image‐Guided Peritoneal Access and Management of Complications in Peritoneal Dialysis
Authors: Taylor Paul M. 
Published: March 2003

AbstractThe principal complications of continuous ambulatory peritoneal dialysis (CAPD), namely malposition of the dialysis catheter, peritonitis, exit site infection, leakage of dialysis fluid, sclerosing peritonitis, and renal cysts and tumors, are considered in this article. The techniques that are used to reposition displaced dialysis catheters and extend the duration of dialysis are described. The role of imaging in establishing the diagnosis of peritonitis is relatively small. However, both computed tomography (CT) and ultrasound may be used to identify loculation of fluid and localized sites of sepsis, and permit percutaneous drainage. Ultrasonography of the catheter track through the percutaneous tissues allows identification of pericatheter collections in patients with exit‐site infection. The technique of CT peritoneography is helpful in establishing sites of dialysis fluid leakage. These commonly occur at the site of entry of the dialysis catheter, through abdominal incisions, or along the patent tunica vaginalis into the scrotum. The appearances on CT of sclerosing peritonitis reflect pathologic changes and are characterized by the presence of peritoneal thickening and calcification. Bowel obstruction, which may develop in sclerosing peritonitis, can be identified on abdominal radiographs or barium studies of the gastrointestinal tract. Acquired renal cystic disease and renal carcinomas occur in a significant proportion of patients undergoing CAPD. Ultrasound is the investigation of first choice in the identification and clarification of the pathology (cystic or solid) of suspected renal masses.
Age‐Specific Reference Ranges for Prostate Specific Antigen in Young Men: Retrospective Study from the National Defense University
Authors: Hartzell Joshua D. , Kao Tzu‐Cheg , Holland John C. , Holt Stephen R. , Moul Judd W. 
Published: March 2003

ABSTRACTObjectives: While controversial, the use of prostate specific antigen (PSA) testing is common and may reduce the morbidity and mortality associated with prostate cancer. The use of age‐specific reference ranges (ASRRs) has been suggested to increase the sensitivity of the PSA test in younger men. The objective of this study was to determine the normal age‐specific reference ranges for a large group of clinically cancer‐free men and to compare these findings with similar studies.Materials and Methods: A retrospective chart review of PSA values was conducted on 1199 students from the National Defense University, Fort McNair, Washington, DC, who were matriculating between 1994 and July 1999. The AsXYM system using MEIA technology with monoclonal antibodies from Abbott laboratories was used to determine the PSA values. The mean, median, 95th percentile, 99th percentile, and range were calculated for each decade.Results: A total of 1123 students between the ages of 30 and 59 were included in the study (1105 with PSA levels ≤ 4.0 ng/ml). The largest number of students (67.4%) fell in the 40–49‐year‐old group. The median PSA level was 0.74 ng/ml. There was a significant correlation between age and PSA level for the 40–59‐year‐old age group (r = 0.06, p = 0.044). There was no significant correlation between age and PSA for the 40–49‐year‐old age group (r = 0.048, p = 0.192). The median PSA value and the 95th percentile increased from 0.7 and 2.3, respectively, in the 40–49‐year‐old age group to 0.8 and 2.7, respectively, in the 50–59‐year‐old age group.Conclusions: The results of this study indicate that PSA values in young men are quite low. The 95th percentile of PSA levels for men in their 40s and 50s was 2.3 and 2.7 ng/ml, respectively, which is significantly lower than the traditional normal value of 4.0 ng/ml. Although further prospective studies are needed, our data suggest that a lower PSA value threshold of 2.0 to 2.5 ng/ml for younger men is reasonable to dictate further evaluation.
Principles of Blood Separation and Component Extraction in a Disposable Continuous‐Flow Single‐Stage Channel
Authors: Hester Jeane , Kellogg Robert M. , Mulzet Alfred P. , Kruger Victor R. , McCredie Kenneth B. , Freireich Emil 
Published: March 2003

Abstract: Guest Editor's Introduction: By 1977, the NCI/IBM 2990 and the Amico Celltrifuge, a conceptually similar instrument that had an identical centrifuge bowl, were being used worldwide. However, a major technical problem remained in that the blood path was still not completely disposable. To overcome this drawback, IBM 2977 was developed. The centrifuge bowl was changed from an axial flow separator to a circumferential flow geometry. The IBM 2997 single‐stage channel instrument was first introduced and followed by the dual‐stage channel instrument to obtain platelet concentrate with minimum lymphocyte contamination. This paper describes the basic design, operation conditions, and collection performance of the single‐stage channel IBM 2977. This paper was printed in Blood, vol 54, page 254–268 (1979) and reprinted here with permission.A single‐stage disposable channel and seal that provides for leukocyte and granulocyte collection by continuous‐flow cell separation (CFCS) has been designed by the IBM Corporation. This paper describes (1) the separation characteristics of whole blood as it responds to varying gravitational (G) forces and flow rates through the channel;
(2) the mechanism by which the buffy coat accumulates and is extracted;
(3) the efficiency of extraction;
(4) those donor and procedural variables that contribute to the final yield;
(5) posttransfusion increment response in patients; and
(6) the functional integrity of the cells collected.
Influence of Experimental Flooding on Litter Dynamics in a Rio Grande Riparian Forest, New Mexico
Authors: Ellis Lisa M. , Molles Manuel C. , Crawford Clifford S. 
Published: March 2003

AbstractFlow regulation, which has largely eliminated flooding along the Rio Grande in central New Mexico, has substantially changed the riparian ecosystem. We investigated managed flooding as a means of restoring ecosystem function. After collecting baseline data during 1991 and 1992 in two riparian forest sites that had not flooded for about 50 years, we flooded an experimental site for 27–32 days during late spring of 1993, 1994, and 1995, leaving the reference site unflooded. During the final year of the study we compared these sites to two additional sites located within the riverside levee, one of which has been flooding naturally while the second remained largely unflooded. Three years of experimental flooding did not change the total biomass of either woody debris or forest‐floor litter at the experimental flood site. Both woody debris and forest‐floor litter, however, were significantly lower at the natural flood site than at the experimental flood site and two unflooded sites. Leaf and wood decomposition rates increased with flooding. The decay rate for cottonwood logs at the unflooded site (0.010 per year) predicted a half‐life of 69.3 years, while the decay rate of 0.065 per year after 3 years of experimental flooding predicted a half‐life of 10.6 years. This suggests that a decade of annual flooding may be used to restore the organic debris to pre‐regulation levels. Flooding may also have caused an increase in litter production. These results suggest that experimental flooding has initiated a process of restoring ecosystem function within the riparian forest.