Renal resistive index in patients supported with a durable continuous flow left ventricular assist device.

BACKGROUND: The impact of continuous flow resulting from contemporary left ventricular assist devices (LVAD) on renal vascular physiology is unknown. Renal resistive index (RRI) reflects arterial compliance, as well as renal vascular resistance, contributed by afferent and efferent arteriolar tone, the renal interstitium as well as renal venous pressures. METHODS: Prospective, single center study with renal Doppler evaluation at baseline (pre-implant) and at 3-months support. Outcomes assessed include need for post-operative renal replacement therapy (RRT), worsening renal function (WRF) defined as persistent increase from pre-implant KDIGO chronic kidney disease stage, right ventricular (RV) failure, and survival to transplantation. RESULTS: Pre-implant RRI did not predict cardiorenal outcomes including right heart failure, need for renal replacement therapy or worsening renal function. Post-implant RRI was significantly lower than pre-implant RRI, with a distinct Doppler waveform characteristic of continuous flow. Post-implant renal end-diastolic velocity, but not RRI, correlated strongly with LVAD flow (Spearman rho -0.99, p < 0.001), with trend toward correlation with mean arterial pressure (Spearman's rho 0.63, p = 0.129). There was a negative correlation between post-implant RRI and mean pulmonary artery pressure (Spearman's rho -0.81, p = 0.049), likely driven by elevated pulmonary capillary wedge pressure (Spearman's rho -0.83, p = 0.058). CONCLUSION: The hemodynamic contributors to RRI in LVAD supported patients are complex. Higher mean pulmonary artery and pulmonary capillary wedge pressures seen in lower RRI may reflect a smaller difference in systolic and diastolic flow. Future simultaneous Doppler assessment of the LVAD outflow graft and RRI may help understand the hemodynamic interactions contributing to this index.

What is the traditional method of resistance training: a systematic review.

INTRODUCTION: Many resistance studies state that they used the traditional method of resistance training in the intervention. However, there is a wide difference on the characteristics of the training protocols used even though they are labeled as "the traditional method." There is no clear definition and characteristics for the traditional method of resistance training. The aim of this study was to describe the most common definitions and references, and also the main characteristics of the training variables of the studies using the traditional training method for strengthening. EVIDENCE ACQUISITION: Searches were carried out in Pubmed, Embase, SPORTDiscus and Web of Science. We included randomized controlled trials that included a strengthening program using the "traditional method" and that evaluated hypertrophy and/or maximum strength in healthy individuals. EVIDENCE SYNTHESIS: The initial search resulted in 26,057 studies, but only 39 studies were eligible and included in this review. The common characteristics of the traditional training protocol were frequency of 3 sessions/week, 3 sets of 9 repetitions, with weight =75% 1RM. The movement time was 2±1 seconds for the concentric and for the eccentric phases. Resting time between sets was 2±1 minutes. The concepts used to define the method as traditional and the characteristics of the intervention protocols were different. The American College of Sports Medicine (ACSM) was the most cited reference. CONCLUSIONS: The "traditional method of resistance training" can be defined as: "Three (±1) sets of 9±6 repetitions of concentric and eccentric exercises using an external load of 75±20% of one maximum repetition, completed 3±1 times/week.

Evaluating the nodulation status of leguminous species from the Amazonian forest of Brazil.

Numerous leguminous species are used or have potential uses for timber production, pharmacological products, or land reclamation. Through N(2)-fixation, many leguminous trees contribute to the N-balance of tropical wetlands and rainforests. Therefore, studies of the N(2)-fixation ability of leguminous species appear to be crucial for the better use and conservation of these resources. The global nodulation inventory in the Leguminosae family is constantly being enriched with new records, suggesting the existence of undiscovered nodulated species, especially in tropical natural ecosystems and other hot spots of biodiversity. In this respect, the nodulation of leguminous species from the Amazonian forest of Porto Trombetas (Brazil) was surveyed. Overall, 199 leguminous species from flooded and non-flooded areas, were examined for their nodulation status by combining field observations, seedling inoculations, and screening of N(2)-fixing bacterial strains from the collected nodules. The results revealed a tendency for a higher relative frequency of nodulation in the species from the flooded areas (74%) compared with those from the non-flooded areas (67%). Nodulation was observed in the Caesalpinioideae, Mimosoideae, and Papilionoideae, with 25, 88, and 84% of the examined species in each subfamily, respectively. Of the 137 nodulated leguminous species, 32 including three Caesalpinoideae, 19 Mimosoideae, and 10 Papilionoideae are new records. One new nodulated genus (Cymbosema) was found in the Papilionoideae. Twelve non-nodulating leguminous species were also observed for the first time. The results are discussed based on the systematics of the Leguminosae family and the influence of available nutrients to the legume-bacteria symbiosis.

Successful use of topical mitomycin C for the treatment of a putative neoplastic vascular mass on the nictitating membrane of a dog.

A nine-year-old female desexed Great Dane presented with a painful, proliferative, soft red putative neoplastic vascular mass on the nictitating membrane. Three 7-day cycles of the topical cytotoxic drug mitomycin C 0.04%, applied four times daily to the lesion using a low-dose alternate-week pulse therapy, brought about rapid remission of the lesion. The lesion was still in remission at time of euthanasia some 13 months later.

In vivo tissue reaction within the outflow conduit in patients supported by HeartWare HVAD.

AIM: The frequency, extent, and nature of tissue ingrowth within the continuous-flow left ventricular assist device (cf-LVAD) outflow conduit has not been systematically assessed. We sought to characterize conduit histopathology at explantation in a cohort of patients with HeartWare ventricular assist device (HVAD) and assess the effect on pump performance. METHODS: Patients undergoing routine histopathological assessment of a HeartWare HVAD removed at transplantation or autopsy were assessed. Outflow conduits were examined macroscopically, and visible tissue was sectioned for microscopic evaluation. In patients who had undergone prior contrast-enhanced computerized tomography (CT) with HVAD in situ, the outflow conduit was measured at the aortic anastomosis and 5 cm proximal to the anastomosis, in the axial and sagittal planes. All patients had their pump flow, flow pulsatility, current, and speed determined from log files examined at 1, 3, 6, 9, and 12 months after LVAD implantation. RESULTS: Twenty-five consecutive patients were assessed (24 LVAD, 1 biventricular assist device (BiVAD)). Of the 26 outflow grafts assessed, there was evidence of tissue ingrowth reaction in 24 (92%) grafts. The most common site was the distal anastomosis (18/24, 75%), with the graft body involved in 14 of 24 (58%) grafts. Microscopic evaluation revealed acute inflammatory infiltrate in 4 of 24 grafts (17%), chronic inflammatory infiltrate in 14 of 24 (58%), neointima formation in 18 of 24 (75%) and fibrosis in 18 of 24 (75%) grafts. The median depth of tissue was 1 mm (range, 0-2 mm). The mean conduit diameter was 9.5 ± 0.6 mm at the aortic anastomosis compared with 11.1 ± 0.5 mm 5 cm proximal to the anastomosis (p < 0.0001). In patients with unchanged pump speed one month after implantation, analysis of log files revealed a significant (5.8 ± 8.6%) decrease in pump flow (4.65 ± 0.86 vs 4.38 ± 0.92 L/min, p = 0.01) and flow pulsatility (5.00 ± 1.10 vs 4.16 ± 1.05 L/min, p = 0.006). CONCLUSIONS: There is evidence of tissue formation within the HVAD outflow conduit in the vast majority of patients, most commonly located at the aortic anastomosis. This is associated with significantly decreased pump flow over time.

Isospin in nuclei.

In the article "Isospin in nuclei" by D. Robson [179, 133 (1973)], several incorrect illustrations were included in Fig. 1. The errors include the following: row a, illustration 5; row b, the (6)(3)Li and (6)(5)B illustrations; and row c, the (6)(2)He illustration. A corrected version of Fig. 1 is shown below.

Isospin in Nuclei: Isospin has been reborn as an important and useful quantum number for all nuclei.

The major feature of isospin in nuclei that I have discussed here is its application to all nuclei. The rebirth of this quantum number in nuclear physics occurred in the early 1960's and was initiated almost entirely by the important work of Anderson et al. (4) and Fox et al. (5). There is still great interest in the use of isospin in its fullest sense as predicted by Wigner (3), and indeed isospin concepts have been largely responsible for demonstrating that nuclei in the doubly "magic number" region of (208)Pb are remarkably in agreement with shell model theory. The early experiments have also initiated a whole new set of more sophisticated experiments (some of which I have briefly alluded to above) which promise to keep many physicists busy for a long time to come. A particularly interesting series of experiments are those being performed (15) at Duke University with high-resolution proton beams. This work shows the highly detailed nature of analogue resonances, that is, as coherent superpositions of many complicated compound states yielding a beautifully modulated wave train, the modulation being observed only in conventional experiments with poor-resolution proton beams. Similarly, nuclear theorists have been led to vastly improve their interpretation of, and computational techniques for, both nuclear reactions and nuclear structure in order to meet the more stringent tests provided by such experiments. Perhaps a lesson can be learned from the historical development of the isospin concept. In the past the belief that T . T would not significantly commute with the dynamical Hamiltonian so that isospin would not be conserved sufficiently well enough certainly delayed the nuclear travels of isospin into the realm of heavy nuclei. Hopefully the same mistake will not occur in the future for other approximate symmetries of nature.

Allylglucosinolate and herbivorous caterpillars: a contrast in toxicity and tolerance.

Allylglucosinolate, found in many cruciferous plants, is acutely toxic to Papilio polyxenes larvae, which do not normally attack crucifers. By contrast, larval growth of Pieris rapae, a crucifer specialist, is not affected even by artificially high concentrations of allylglucosinolate. Larval growth of Spodoptera eridania, a generalist feeder, is inhibited by high but not by low concentrations of the compound.

"Wolf-in-Sheep's-Clothing" Strategy of a Predaceous Insect Larva.

The larva of the green lacewing Chrysopa slossonae lives in colonies of the wooly alder aphid Prociphilus tesselatus upon which it feeds. It disguises itself as its prey by plucking some of the waxy "wool" from the bodies of the aphids and applying this material to its own back. The investiture protects it from assault by the ants that ordinarily "shepherd" the aphids. Larvae artifically denuded are seized by the ants and removed from the aphid colonies. A larva requires on the average less than 20 minutes to coat itself with wax. A hungry denuded larva gives the coating procedure about the same behavioral priority as feeding.

Canadian supportive care recommendations for the management of neutropenia in patients with cancer.

Hematologic toxicities of cancer chemotherapy are common and often limit the ability to provide treatment in a timely and dose-intensive manner. These limitations may be of utmost importance in the adjuvant and curative intent settings. Hematologic toxicities may result in febrile neutropenia, infections, fatigue, and bleeding, all of which may lead to additional complications and prolonged hospitalization. The older cancer patient and patients with significant comorbidities may be at highest risk of neutropenic complications. Colony-stimulating factors (csfs) such as filgrastim and pegfilgrastim can effectively attenuate most of the neutropenic consequences of chemotherapy, improve the ability to continue chemotherapy on the planned schedule, and minimize the risk of febrile neutropenia and infectious morbidity and mortality. The present consensus statement reviews the use of csfs in the management of neutropenia in patients with cancer and sets out specific recommendations based on published international guidelines tailored to the specifics of the Canadian practice landscape. We review existing international guidelines, the indications for primary and secondary prophylaxis, the importance of maintaining dose intensity, and the use of csfs in leukemia, stem-cell transplantation, and radiotherapy. Specific disease-related recommendations are provided related to breast cancer, non-Hodgkin lymphoma, lung cancer, and gastrointestinal cancer. Finally, csf dosing and schedules, duration of therapy, and associated acute and potential chronic toxicities are examined.

The changing face of infection: a comparative review of admissions to a regional infection unit over three decades.

BACKGROUND AND AIMS: Our group previously published retrospective analyses of 12 months of admissions to the Grampian Regional Infectious Diseases Unit from 1980-81 and from 1991. This study aimed to collect data in 2001 and to compare annual admission numbers, diagnoses, duration of stay and outcome in 1980-81, 1991 and 2001. METHODS: Data on all admissions was collected prospectively throughout 2001. This was compared with the previously published data. RESULTS: Total admissions rose from 605 in 1980-81 to 900 in 1991 and to 1152 in 2001. Sixty one percent of admissions in 1980-81 were confirmed as having infection compared to 72% in 1991 and to 83% in 2001. The most common reason for admission in 2001 was skin and soft tissue infection, but this was only the ninth commonest reason in 1981. Mean length of stay fell from 9.6 days in 1980-81 to 7.4 days in 1991 and to 5.5 days in 2001. The mortality rate fell from 3.1% in 1981 and 1991 to 1.0% in 2001. CONCLUSIONS: This study demonstrates significant changes in type, number and outcome of admissions to a regional infection unit. We discuss possible reasons for these changes.

Radiation dose and leukemia risk in patients treated for cancer of the cervix.

To quantify the risk of radiation-induced leukemia and provide further information on the nature of the relationship between dose and response, a case-control study was undertaken in a cohort of over 150,000 women with invasive cancer of the uterine cervix. The cases either were reported to one of 17 population-based cancer registries or were treated in any of 16 oncologic clinics in Canada, Europe, and the United States. Four controls were individually matched to each of 195 cases of leukemia on the basis of age and calendar year when diagnosed with cervical cancer and survival time. Leukemia diagnoses were verified by one hematologist. Radiation dose to active bone marrow was estimated by medical physicists on the basis of the original radiotherapy records of study subjects. The risk of chronic lymphocytic leukemia, one of the few malignancies without evidence for an association with ionizing radiation, was not increased [relative risk (RR) = 1.03; n = 52]. However, for all other forms of leukemia taken together (n = 143), a twofold risk was evident (RR = 2.0; 90% confidence interval = 1.0-4.2). Risk increased with increasing radiation dose until average doses of about 400 rad (4 Gy) were reached and then decreased at higher doses. This pattern is consistent with experimental data for which the down-turn in risk at high doses has been interpreted as due to killing of potentially leukemic cells. The dose-response information was modeled with various RR functions, accounting for the nonhomogeneous distribution of radiation dose during radiotherapy. The local radiation doses to each of 14 bone marrow compartments for each patient were incorporated in the models, and the corresponding risks were summed. A good fit to the observed data was obtained with a linear-exponential function, which included a positive linear induction term and a negative exponential term. The estimate of the excess RR per rad was 0.9%, and the estimated RR at 100 rad (1 Gy) was 1.7. The model proposed in this study of risk proportional to mass exposed and of risk to an individual given by the sum of incremental risks to anatomic sites appears to be applicable to a wide range of dose distributions. Furthermore, the pattern of leukemia incidence associated with different levels of radiation dose is consistent with a model postulating increasing risk with increasing exposure, modified at high doses by increased frequency of cell death, which reduces risk.

A vesicular (blistering) skin condition in a dog following putative contact exposure to Plumbago auriculata.

CASE REPORT: A 2-year-old male Airedale Terrier was presented with an acute and painful, predominantly ventral, vesicular skin eruption following putative dermal contact with Plumbago auriculata (Sky Flower, Leadwort). Prompt dermal decontamination and supportive therapy brought about a rapid recovery in the patient. CONCLUSION: Contact with botanical triggers is an important consideration for causes of acute vesicular skin conditions in dogs.

Rate control and sinus rhythm maintenance in atrial fibrillation: national trends in medication use, 1980-1996.

BACKGROUND: Little is known about national patterns of pharmacological treatment of atrial fibrillation, in particular, use of medications for ventricular rate control and for restoration and maintenance of sinus rhythm. METHODS: We analyzed 1555 visits by patients with atrial fibrillation to randomly selected office-based US physicians included in National Ambulatory Medical Care surveys conducted in 1980, 1981, 1985, and 1989 through 1996. To determine national trends, we evaluated the proportion of atrial fibrillation visits with reported use of rate control medications (digoxin and antiarrhythmics in classes II and IV) and sinus rhythm medications (classes IA, IC, and III). RESULTS: The use of rate control agents decreased from 79% of atrial fibrillation visits in 1980-1981 to 62% in 1994-1996. Declining use was noted for both digoxin (76% in 1980-1981 to 53% in 1994-1996) and beta-blockers (19%-13%). After their introduction, the use of verapamil hydrochloride and diltiazem hydrochloride increased to 15% of atrial fibrillation visits in 1994-1996. Sinus rhythm agent use decreased from 18% of visits in 1980-1981 to 4% in 1992-1993 and then rose to 13% in 1994-1996. The use of class IA agents declined from 18% in 1980-1981 to 3.5% in 1992-1993 and then increased to 8% in 1994-1996. Quinidine remained the most widely used sinus rhythm medication, despite its declining share of this category. Newly available sotalol hydrochloride and amiodarone hydrochloride were used in 3.6% of visits in 1994-1996. CONCLUSIONS: Despite changes in the treatment of atrial fibrillation, digoxin remains the dominant rate control medication. Medications for sinus rhythm maintenance are not widely used. Quinidine use declined prominently in the 1980s, possibly because of concerns about proarrhythmic effects. The use of sinus rhythm agents, however, is now rising.

Recurrent flank alopecia in a Tibetan Terrier.

Recurrent flank alopecia is described in a 2-year-old, male, neutered Tibetan Terrier with concurrent atopic dermatitis. The diagnosis of recurrent flank alopecia was made after 3 consecutive years of localised, winter-onset alopecia. The diagnosis was based on history, compatible clinical signs and supportive histopathology. The diagnosis was complicated by the presence of concurrent pruritic dermatitis. To our knowledge this is the first report of recurrent flank alopecia in this breed.

Juvenile cellulitis in an 8-month-old dog.

An 8-month-old, crossbred dog, presented with a painful, swollen face. The problem was of 4 weeks duration and had not responded to antibiotics. A diagnosis of canine juvenile cellulitis was based on the clinical presentation and supportive cytological and histopathological changes. Attempts to identify canine distemper virus were not successful. Complete resolution occurred with glucocorticoid therapy. This is the first report of canine juvenile cellulitis in a dog of this age.

Detectability of pituitary PRL and GH by immunoassay is increased by thiols and suppressed by divalent cations.

The amount of pituitary PRL detected by RIA in extracts of tissue and of secretory granules was augmented by thiols or EDTA in the extractant, and diminished by divalent cations or cysteamine. GH was affected by thiols and cations similarly, but to a lesser extent, and was not influenced by EDTA or cysteamine. For full immunologic detection of tissue PRL and GH, thiol-dependent mechanisms appear to be required to unmask immunoreactive sites from the poorly immunoreactive oligomeric granule storage forms. Interpretation of studies which rely on measurement of tissue PRL and GH content by RIA, immunoprecipitation, or electrophoretic detection should be reassessed in light of these observations.

Alcohol-induced alterations in calcium metabolism in the pregnant rat.

The effect of alcohol ingestion during pregnancy on maternal calcium metabolism was investigated by allowing pregnant rats to ingest Purina Rat Chow ad libitum along with 20% ethanol in their drinking water from day 6 to 19 of pregnancy. Ethanol constituted 50% of the caloric intake and resulted in blood levels of 98 mg/dl on day 19 of gestation. Control rats were pair-fed with rat Chow and dextrimaltose was isocalorically substituted for ethanol in the drinking water. Alcohol consumption was attended by decreased serum levels of calcium (7.3 +/- 0.5 versus 9.5 +/- 0.3 mg/dl, p less than 0.01), and phosphorus (5.7 +/- 0.5 versus 7.5 +/- 0.3 mg/dl, p less than 0.01), as well as by lowered tubular reabsorption of phosphate (88.6 +/- 4.6 versus 95.0 +/- 0.7%, p less than 0.05). The fasting urinary calcium/creatinine ratio (Ca/Cr), an index of bone resorption, was increased in the alcohol-consuming rats (0.41 +/- 0.08 versus 0.24 +/- 0.04, p less than 0.05). In contrast, alcohol administered to nonpregnant female rats for the same time period and resulting in blood levels of 129 mg/dl had no effect on serum calcium, phosphorus, tubular reabsorption of phosphate, or fasting urinary Ca/Cr. The data suggest that alcohol ingestion during pregnancy, a time of increased calcium requirement, produces biochemical changes consistent with secondary hyperparathyroidism.

Effect of supplementary feeding on recovery from mild to moderate wasting in preschool children.

Three-month recovery rates from moderate wasting (less than 90% weight-for-length) were compared in 6-24-mo-old children in four Guatemalan villages that had been randomly assigned to receive a moderate (Atole) or low (Fresco) energy supplement. The recovery rate (Rr) in the Atole villages was 12% higher than in the Fresco villages (P less than 0.05). This effect was above all due to the children in the Atole villages who consumed greater than or equal to 10% of the daily recommended dietary intake of energy (RDI) from the supplement (high-Atole group) and whose total energy intake (including home diet) was 10.5% of the RDI higher than a comparable high-Fresco group with low supplemental energy intake. All those in the high-Atole group whose wasting was due to malnutrition recovered. Much of this recovery (range 29-52%) was due to the increased supplementation. This proportion rose after potential confounding variables were controlled for.

Age-specific responsiveness of weight and length to nutritional supplementation.

Evaluation of the responsiveness of weight and length to supplementary feeding shows that the two periods of greatest response coincide with weaning (ages 3-6 mo) and peak incidence and duration of diarrheal disease (ages 9-12 mo). Analyses were done for seven consecutive nonoverlapping intervals comparing children randomly assigned to receive supplemental feeding from birth to age 36 mo or to serve as control subjects. Absolute responsiveness was greatest between ages 3-6 mo; supplemented infants grew 0.61 cm more and gained 162 g more than did unsupplemented infants (p less than 0.005). Relative to rates of growth, responsiveness was greatest between ages 9 and 12 mo (the period of peak diarrheal prevalence), followed by ages 3-6 mo (the period of weaning). Responsiveness to supplementation is thus directly related to age-dependent risk patterns for malnutrition. Targeting supplementation programs to coincide with periods of high nutritional risk should maximize their effectiveness in reducing malnutrition, though caution should be exercised to avoid disruption of breast-feeding.