A comparative study of three kidney biomarker tests in autosomal-dominant polycystic kidney disease

BACKGROUND: The relationship between the progress of tubular damage and renal insufficiency in autosomal-dominant polycystic kidney disease (ADPKD) is a subject of doubtless interest, and is the object of this present work. METHODS: A total of 92 adult ADPKD patients of both genders were studied, none of which presented end-stage renal disease (ESRD), and classified according to an ultrasound score based on kidney size and number of cysts. Urinary albumin and beta-N-acetylhexosaminidase (Hex) and its isoenzymes were determined, together with serum glutathione peroxidase, cystatin C, creatinine, and urea. RESULTS: A frequent elevation of the urinary Hex was found and an alteration of its isoenzymatic profile, with 31% of the normotensive patients with normoalbuminuria already presenting an increased proportion of Hex B isoenzyme. Keeping age constant, a partial significant correlation was found between the ultrasound score and the proportion of Hex B (r = 0.352, P < 0.05), but not with albuminuria or cystatin C. In 42 patients the different biochemical variables were again determined after 1 year, finding that in the 13 normotensive patients with normoalbuminuria there had been a significant decrease in the concentration of cystatin C (P < 0.05), and a significant increase in the urinary excretion of albumin and Hex B isoenzyme (P < 0.05). By the other hand, in the other 29 patients with micro- or macroalbuminuria and hypertension, no significant differences were found. CONCLUSION: The results point toward an important participation of tubular damage in the pathogenesis of this disease. It may also be suggested that in normotensive and normoalbuminuric ADPKD patients, a gradual increase of glomerular filtration would be produced. After the start of hypertension and microalbuminuria, the glomerular filtration rate (GFR) would decrease progressively, although more slowly.     

Tarsal navicular stress fractures: radiographic evaluation

Tarsal navicular stress fractures are a potential source of disabling foot pain in physically active individuals. The diagnosis of tarsal navicular stress fracture requires a high index of clinical and radiographic suspicion because the fracture is only rarely evident on routine radiographs or standard tomograms. The radiographic diagnosis of a tarsal navicular stress fracture may require anatomic anteroposterior tomograms or a radionuclide bone scan with plantar views. Radiographic examinations of 23 fractures in 21 patients are evaluated.     

Patellofemoral forces after total knee arthroplasty: effect of extensor moment arm

Total knee arthroplasty implant designs with larger extensor moment arms theoretically should generate lower extensor forces for the same externally applied loads. This study measured knee kinematics, quadriceps forces, and patellofemoral forces under conditions of dynamic knee extension under load in two knee designs with differing quadriceps moment arms. Six human cadaver knees were tested both before implantation and after sequential implantation with two posterior cruciate retaining designs. The extensor moment arm of the LMA (long extensor moment arm design, Scorpio, Howmedica Osteonics, Rutherford, NJ) was approximately 1 cm longer than that of the Control design (7000, Howmedica Osteonics). Quadriceps tension was measured during dynamic closed kinetic chain knee extension. Patellar compressive and shear forces were also recorded using a patellar component instrumented with a custom triaxial load transducer. Knee kinematics were monitored using a three-dimensional electromagnetic tracking device. Both designs produced similar patterns of femoral rollback and tibial rotation. Quadriceps tension was lower in the LMA design compared with the Control design. Patellofemoral compressive forces were also significantly reduced in the LMA design when compared with Control (8-18% lower at angles greater than 50 degrees flexion). The design with the longer extensor moment arm required less quadriceps force to extend the knee under load and reduced patellofemoral compressive forces. Reduced quadriceps forces may facilitate postoperative rehabilitation and activities such as stair climbing. Reduction in patellofemoral forces could reduce patellar complications such as anterior knee pain, component wear, and loosening.     

Oxidized zirconium femoral components reduce polyethylene wear in a knee wear simulator

Polyethylene wear remains a major problem that can jeopardize the long-term durability of prostheses used in total knee arthroplasty. Oxidized zirconium is a material that combines the strength of a metal with the wear properties of a ceramic. This study evaluated the wear rates of polyethylene inserts against oxidized zirconium femoral components. Three oxidized zirconium femoral components and three Co-Cr femoral components of identical geometry used in total knee arthroplasty were articulated against standard tibial components with modular tibial inserts made of noncross-linked ultra-high molecular weight polyethylene. Gravimetric and volumetric polyethylene wear rates were calculated after 5 million gait cycles on an AMTI knee wear simulator. Oxidized zirconium reduced polyethylene wear by 42% compared with Co-Cr alloy. This study shows that oxidized zirconium can reduce polyethylene wear substantially when used for fixed-bearing total knee arthroplasty.     

Chronotherapy of hypertension

PURPOSE OF REVIEW: Blood pressure displays appreciable predictable-in-time circadian variation. The chronotherapy of hypertension takes into account the clinically relevant features of the 24-h pattern of blood pressure, e.g. the accelerated morning rise and nighttime decline during sleep, plus potential administration circadian time determinants of the pharmacokinetics and dynamics of antihypertensive medications. RECENT FINDINGS: Significant administration-time differences in the kinetics (i.e. chronokinetics) plus the beneficial and adverse effects (termed chronodynamics) of antihypertensive drugs are well known. Thus, bedtime, but not morning, dosing with cilnidipine significantly reduces nocturnal blood pressure. In addition, the dose-response curve, therapeutic coverage, and efficacy of the doxazosin gastrointestinal therapeutic system are all markedly dependent on the circadian time of drug administration. Moreover, valsartan administration at bedtime as opposed to upon awakening results in improved diurnal/nocturnal blood pressure ratio, such that the dosing time of valsartan can be chosen in relation to the dipper status of any given patient to improve therapeutic benefit and reduce cardiovascular risk. SUMMARY: Nocturnal hypertension, which is characterized by the loss or even reversal of the expected 10-20% sleep-time blood-pressure decline, increases the risk of cardiac and cerebrovascular events. Chronotherapy provides a means of individualizing treatment of hypertension according to the circadian profile of blood pressure of each patient. The chronotherapeutic strategy constitutes a new option to optimize blood-pressure control and to reduce risk.     

Proposed association between the COL1A1 and COL1A2 genes and otosclerosis is not supported by a case-control study in Spain

Otosclerosis (OTSC) is one of the most common causes of hearing loss in white adults. The COL1A1 and COL1A2 genes coding for type-I collagen have been proposed as candidate genes in the development of OTSC. The COL1A1 gene was recently reported to be associated with the condition on the basis of a population-based case-control study. We report here an independent study of association between COL1A1 and COL1A2 gene polymorphisms and OTSC, in a case-control sample from a population of Caucasian individuals living in Northwest Spain. Specifically, we studied two COL1A1 polymorphisms previously reported to be associated with OTSC, and six COL1A2 polymorphisms. We performed diverse association analyses based on alleles, genotypes, and two-locus haplotypes. We found no evidence supporting the putative link of COL1A1 and COL1A2 genes with OTSC.     

Clarifying the implementation of nursing care systematization

This study has reviewed the national literature regarding nursing assistance systematization (NAS), with the aim of identifying the difficulties implementing this practice and the factors that interfere with and harm its implementation. The MEDLINE, LILACS, and BDENF databases have been utilized and six studies published in nursing periodicals in the last five years have been surveyed. The results indicate several difficulties implementing the NAS and several factors that interfere negatively with its implementation. Considering the importance of this assistance methodology for valuing professional nursing, it is necessary to reflect on/discuss its practical difficulties so that we can overcome them, making it a pleasurable activity capable of providing nurses with autonomy and providing patients with quality assistance.     

Haemostatic genetic risk factors in arterial thrombosis

Haemostasis plays an integral role in arterial thrombotic disease. However, establishing which of the factors are risk factors has proven surprisingly difficult. Because of its technical simplicity and digital nature, the study of haemostatic polymorphisms as risk factors has grown in popularity. Once established as a risk factor, a genetic polymorphism has the potential to aid selective prophylaxis and therapy of disease. Numerous reports have now been published on polymorphisms of coagulation and fibrinolytic factors, of coagulation and fibrinolytic inhibitory proteins, and of platelet membrane glycoprotein receptors. This article describes the polymorphisms and evaluates the results of these studies using the premises of consistency of within-report genotype/phenotype/disease relationships and consistency of outcome between studies. Many studies have been only of association between polymorphisms and disease, a type of study that is prone to error. Furthermore, the collective outcome of these studies has primarily been inconsistent. It is concluded that despite the early promise of polymorphisms as risk factors, fresh approaches differing in scale and design are now required to clarify their possible importance.     

Removal of bowel aerobic gram-negative bacteria is more effective than immunosuppression with cyclophosphamide and steroids to decrease natural alpha-galactosyl IgG antibodies

Abstract: Natural α-Galactosyl (Gal) antibodies play an important role in the rejection of pig xenografts by humans and Old World monkeys. In this study we investigate the efficacy of two different strategies to reduce the serum level of natural anti-Gal antibodies. On the one hand, removal of aerobic gram-negative bacteria from the intestinal flora, because anti-Gal antibodies appear to be produced as a result of the continuous sensitization by these microorganisms. On the other hand, we studied the effect on these antibodies of an immunosuppressive regimen of cyclophosphamide and steroids. Ten baboons were treated for three months with norfloxacin (Nor Group; n = 6) or cyclophosphamide and steroids (CyP Group; n = 4). A further four baboons did not receive any treatment (Control Group). Aerobic gram-negative bacteria became negative in stools of the Nor Group after two weeks of treatment, and remained undetectable until week 7. Thereafter, a gradual increase on the fecal concentration of aerobic gram-negative bacteria was observed despite the norfloxacin treatment. The mean anti-Gal IgG in the Nor Group gradually declined from week 4 to 9 to a mean of 62.7 ± 18% of the baseline level, and during this period were significantly lower than in the CyP ( P  < 0.02) and the Control ( P  < 0.05) groups. No differences were observed between the three groups during the 16 weeks of follow-up in serum levels of anti-Gal IgM, hemolytic anti-pig antibodies, total IgG, IgM and IgA. In conclusion, removal of normal aerobic gram-negative bacteria from the intestinal flora is more effective than immunosuppression with CyP and steroids in reducing the level of natural anti-Gal antibodies, although there is no discernible effect on IgM antibodies.