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In primary aldosteronism (PA), the occurrence of K+ loss and hypertension suggest alterations in renal tubular transport, but the molecular basis of these alterations in humans is unclear. In this study, urinary extracellular vesicles (uEVs) isolated from patients undergoing fludrocortisone suppression testing (FST, as a means of confirming or excluding PA) were analyzed using mass spectrometry-based proteomics to determine the combined effects of an aldosterone analogue, NaCl and KCl supplementation on renal tubular protein abundance. Of quantified proteins, the Cl−/HCO3− exchanger pendrin decreased by a median 37% [−15, 57] (P < 0.01) and the potassium channel ROMK increased by a median 31% [−10, 85] (P < 0.01) during FST among 10 PA subjects. The trends remained, but to a lesser degree, in two subjects cured of PA by unilateral adrenalectomy. In PA subjects, plasma K+ increased from median 3.6 to 4.2 mM (P < 0.01) and 24 h urine K+ from 101 to 202 mmol (P < 0.01), while 24 h urine Na+/K+ decreased from 2.3 to 0.8 (P < 0.01). At baseline, pendrin negatively correlated with plasma K+ (P < 0.05) and positively correlated with plasma aldosterone (P < 0.01). There were no clear correlations between Δ pendrin (Δ = D4–D0) and changes in blood or urine variables, and no correlations between ROMK in any of the blood or urine variables either at baseline or during FST. We conclude that oral co-administration of mineralocorticoid and KCl in PA patients is associated with reduced pendrin and enhanced ROMK in uEVs. Pendrin reduction during FST suggests that the suppressive effects of oral KCl may outweigh pendrin upregulation by mineralocorticoids.

The sodium–hydrogen exchanger isoform 3 (NHE3, SLC9A3) is abundantly expressed in the gastrointestinal tract and is proposed to play essential roles in Na+ and fluid absorption as well as acid–base homeostasis. Mutations in the SLC9A3 gene can cause congenital sodium diarrhea (CSD). However, understanding the precise role of intestinal NHE3 has been severely hampered due to the lack of a suitable animal model. To navigate this problem and better understand the role of intestinal NHE3, we generated a tamoxifen-inducible intestinal epithelial cell-specific NHE3 knockout mouse model (NHE3IEC-KO). Before tamoxifen administration, the phenotype and blood parameters of NHE3IEC-KO were unremarkable compared with control mice. After tamoxifen administration, NHE3IEC-KO mice have undetectable levels of NHE3 in the intestine. NHE3IEC-KO mice develop watery, alkaline diarrhea in combination with a swollen small intestine, cecum and colon. The persistent diarrhea results in higher fluid intake. After 3 weeks, NHE3IEC-KO mice show a ∼25% mortality rate. The contribution of intestinal NHE3 to acid–base and Na+ homeostasis under normal conditions becomes evident in NHE3IEC-KO mice that have metabolic acidosis, lower blood bicarbonate levels, hyponatremia and hyperkalemia associated with drastically elevated plasma aldosterone levels. These results demonstrate that intestinal NHE3 has a significant contribution to acid–base, Na+ and volume homeostasis, and lack of intestinal NHE3 has consequences on intestinal structural integrity. This mouse model mimics and explains the phenotype of individuals with CSD carrying SLC9A3 mutations.

Targeting the collecting duct water channel aquaporin 2 (AQP2) to the plasma membrane is essential for the maintenance of mammalian water homeostasis. The vasopressin V2 receptor (V2R), which is a GS protein-coupled receptor that increases intracellular cAMP levels, has a major role in this targeting process. Although a rise in cAMP levels and activation of protein kinase A are involved in facilitating the actions of V2R, studies in knockout mice and cell models have suggested that cAMP signalling pathways are not an absolute requirement for V2R-mediated AQP2 trafficking to the plasma membrane. In addition, although AQP2 phosphorylation is a known prerequisite for V2R-mediated plasma membrane targeting, none of the known AQP2 phosphorylation events appears to be rate-limiting in this process, which suggests the involvement of other factors; cytoskeletal remodelling has also been implicated. Notably, several regulatory processes and signalling pathways involved in AQP2 trafficking also have a role in the pathophysiology of autosomal dominant polycystic kidney disease, although the role of AQP2 in cyst progression is unknown. Here, we highlight advances in the field of AQP2 regulation that might be exploited for the treatment of water balance disorders and provide a rationale for targeting these pathways in autosomal dominant polycystic kidney disease.

Introduction: Kidney dysfunction poses a high burden on patients and health care systems. Early detection and accurate prediction of kidney disease progression remains a major challenge. Compared to existing clinical parameters, urinary proteomics has the potential to reveal molecular alterations within the kidney that may alter its function before the onset of clinical symptoms. Thus, urinary proteomics has greater prognostic potential for assessment of kidney dysfunction progression. Areas covered: Advances in urinary proteomics for major causes of kidney dysfunction are discussed. The application of urinary extracellular vesicles for studying kidney dysfunction are discussed. Technological advances in urinary proteomics are discussed. The literature was identified using a database search for titles containing ‘proteom*’ and ‘urin*’ and published within the past 5 years. Retrieved literature was manually filtered to retain kidney dysfunctions-related studies. Expert opinion: Despite major advances, diagnosis by urinary proteomics has not been fully applied in any clinical settings. This could be attributed to the complex nature of kidney diseases, in addition to the constraints on study power and feasibility of incorporating mass spectrometry techniques in daily routine analysis. Nevertheless, we are confident that advances in urinary proteomics will soon provide superior insights into kidney disease beyond existing clinical parameters.

Background and Aims Nuclear Factor of Activated T-Cells 5 (NFAT5), also called TonEBP/OREBP, helps protecting kidney cells from the stress of extracellular hypertonic challenge. In response to hypertonicity, NFAT5 rapidly translocates into the nucleus and enhances the transcription of osmoprotective genes. Mice lacking NFAT5 have embryonic lethality, with those surviving having severe renal atrophy and hydronephrosis. Overexpression of a dominant-negative NFAT5 in all epithelial cells of the thick ascending limb, distal tubule and collecting duct (CD) leads to an impairment in the urine concentration, with reduced expression of AQP2 and urea transporters UT-A1 and UT-A2. Here, we generated a novel mouse model to assess the role of NFAT5 in the water transporting principal cells of the CD. Method The mouse model was generated by breeding floxed NFAT5 mice with mice specifically expressing Cre recombinase in AQP2 expressing cells (NFAT5f/f-AQP2cre+/-). AQP2cre+/- mice served as controls. For renal function analysis, mice were kept in metabolic cages for 5 days and water intake, urinary volume, osmolality, and serum and urine electrolytes were evaluated. Mice were euthanized and the kidneys were used for western blot analysis. Results NFAT5f/f-AQP2cre+/- mice show a significant increase of 24 hour urine output compared to the control (KO: 6.267 ± 0.9367 µl/h/g BW vs WT: 0.9593 ± 0.0796 µl/h/g BW), a decrease in the urine osmolality (KO: 505.6 ± 107.6 mOsm/Kg H2O vs WT: 6205 ± 752.7 mOsm/Kg H2O) and urea concentration. After 3h and half intraperitoneal injection of dDAVP (1ug/kg) the osmolality was still significantly low in NFAT5f/f-AQP2cre+/- mice (KO: 743.7 ± 81.77 vs WT: 3342 ± 80.14 mOsm/Kg H2O), as well as after 8h water restriction (KO: 732.8 ± 24.90 vs WT: 3784 ± 450.9 mOsm/Kg H2O). Immunoblotting demonstrated a significant decrease in AQP2, AQP3 and AQP4 abundance in cortical kidney fractions and inner medulla. There were no differences in vasopressin V2 receptor (V2R) and AVP-regulated transporters NKCC2, ROMK and alpha-ENaC. Conclusion We demonstrate that NFAT5 ablation from AQP2-expressing cells results in a urinary concentration defect. NFAT5f/f-AQP2cre+/- mice have a hypoosmotic polyuria, without major effects on the AVP-V2R axis, suggesting Nephrogenic Diabetes Insipidus.

Approximately 25% of the adult population is diagnosed with hypertension and it is therefore one of the biggest challenges for the health sector. The renin-angiotensin-aldosterone system (RAAS) adjusts effective circulating volume and ultimately blood pressure (BP). Accordingly, antihypertensive drugs targeting the RAAS have been a major focus in modern medical treatment. Low and high dietary K+ intakes are associated with increased or decreased BP and risk of cardiac failure, respectively, suggesting that dietary K+ augmentation has the potential to supplement or replace conventional anti-hypertensive drugs. Animal studies have indicated that the beneficial effects of high dietary K+ may be linked to a dominant regulatory role of plasma K+ on key renal transport proteins controlled by the RAAS. However, only a limited number of studies have investigated whether the reported mechanisms in animal models apply to humans. Furthermore, hypertension is often treated with so-called 'K+ sparing' drugs, thus complicating co-treatment with K+ supplementation. In this review, we revisit old concepts of RAAS effects in the kidney, relate them to effects of dietary K+ manipulation, and finally consider the clinical potential of treating hypertension with K+ supplementation alone or in combination with RAAS inhibitors. Collectively, a wealth of data suggest that increased dietary K+ intake may have beneficial effects on BP in the general population, but underlying medical conditions or current treatment regimens need to be carefully considered before implementing K+ supplementation in patients.

Cholinergic receptor activation leads to premature development of hypertension and infiltration of proinflammatory CD161a+/CD68+ M1 macrophages into the renal medulla. Renal inflammation is implicated in renal sodium retention and the development of hypertension. Renal denervation is known to decrease renal inflammation. The objective of this study was to determine the role of CD161a+/CD68+ macrophages and renal sympathetic nerves in cholinergic-hypertension and renal sodium retention. Bilateral renal nerve denervation (RND) and immune ablation of CD161a+ immune cells were performed in young prehypertensive spontaneously hypertensive rat (SHR) followed by infusion of either saline or nicotine (15 mg·kg−1·day−1) for 2 wk. Immune ablation was conducted by injection of unconjugated azide-free antibody targeting rat CD161a+. Blood pressure was monitored by tail cuff plethysmography. Tissues were harvested at the end of infusion. Nicotine induced premature hypertension, renal expression of the sodium-potassium chloride cotransporter (NKCC2), increases in renal sodium retention, and infiltration of CD161a+/CD68+ macrophages into the renal medulla. All of these effects were abrogated by RND and ablation of CD161a+ immune cells. Cholinergic activation of CD161a+ immune cells with nicotine leads to the premature development of hypertension in SHR. The effects of renal sympathetic nerves on chemotaxis of CD161a+ macrophages to the renal medulla, increased renal expression of NKCC2, and renal sodium retention contribute to cholinergic hypertension. The CD161a+ immune cells are necessary and essential for this prohypertensive nicotine-mediated inflammatory response. NEW & NOTEWORTHY This is the first study that describes a novel integrative physiological interaction between the adrenergic, cholinergic, and renal systems in the development of hypertension, describing data for the role of each in a genetic model of essential hypertension. Noteworthy findings include the prevention of nicotine-mediated hypertension following successful immune ablation of CD161a+ immune cells and the necessary role these cells play in the overexpression of the sodium-potassium-chloride cotransporter (NKCC2) in the renal medulla and renal sodium retention. Renal infiltration of these cells is demonstrated to be dependent on the presence of renal adrenergic innervation. These data offer a fertile ground of therapeutic potential for the treatment of hypertension as well as open the door for further investigation into the mechanism involved in inflammation-mediated renal sodium transporter expression. Taken together, these findings suggest immune therapy, renal denervation, and, possibly, other new molecular targets as having a potential role in the development and maintenance of essential hypertension. Listen to this article's corresponding podcast at https://ajpheart.podbean.com/e/cd161a-immune-cells-in-cholinergic-hypertension/ .

This paper presents a novel, agent-based sensing-system reconfiguration methodology for the recognition of time-varying-geometry targets (objects or subjects). A multi-camera activevision system is used to improve form-recognition performance by selecting near-optimal viewpoints along a prediction time horizon. The proposed method seeks to maximize the target visibility in a cluttered, dynamic environment. Simulated experiments clearly show a tangible potential performance gain.

Psychiatric patients treated with lithium (Li(+)) may develop nephrogenic diabetes insipidus (NDI). Although the etiology of Li(+)-induced NDI (Li-NDI) is poorly understood, it occurs partially due to reduced aquaporin-2 (AQP2) expression in the kidney collecting ducts. A mechanism postulated for this is that Li(+) inhibits adenylyl cyclase (AC) activity, leading to decreased cAMP, reduced AQP2 abundance, and less membrane targeting. We hypothesized that Li-NDI would not develop in mice lacking AC6. Whole-body AC6 knockout (AC6(-/-)) mice and potentially novel connecting tubule/principal cell-specific AC6 knockout (AC6(loxloxCre)) mice had approximately 50% lower urine osmolality and doubled water intake under baseline conditions compared with controls. Dietary Li(+) administration increased water intake and reduced urine osmolality in control, AC6(-/-), and AC6(loxloxCre) mice. Consistent with AC6(-/-) mice, medullary AQP2 and pS256-AQP2 abundances were lower in AC6(loxloxCre) mice compared with controls under standard conditions, and levels were further reduced after Li(+) administration. AC6(loxloxCre) and control mice had a similar increase in the numbers of proliferating cell nuclear antigen-positive cells in response to Li(+). However, AC6(loxloxCre) mice had a higher number of H(+)-ATPase B1 subunit-positive cells under standard conditions and after Li(+) administration. Collectively, AC6 has a minor role in Li-NDI development but may be important for determining the intercalated cell-to-principal cell ratio.

Objective:Primary aldosteronism (PA) is a common and potentially curable form of hypertension caused by excess and autonomous production of aldosterone by the adrenal gland. Renal salt homeostasis has profound effects on body fluid and blood pressure maintenance. In the renal distal tubule, aldoster

This paper presents a generic framework for on-line reconfiguration of a multi-camera active-vision system for time-varying-geometry object/subject action recognition. The proposed methodology utilizes customizable pipeline architecture to select optimal camera poses in real time. Subject visibility is optimized via a depth-limited search algorithm. All stages are developed with real-time operation as the central focus. A human action-sensing implementation example demonstrates viability. Controlled experiments, first with a human analogue and, subsequently, with a real human, illustrate the workings of the proposed framework. A tangible increase in action-recognition success rate over other strategies, particularly those with static cameras, is noteworthy. The proposed framework is also shown to operate in real-time. Further experiments examine the effect of scaling the number of obstacles and cameras, sensing-system mobility, and library actions on real-time performance.

The water channel aquaporin-2 (AQP2), expressed in the kidney collecting ducts, plays a pivotal role in maintaining body water balance. The channel is regulated by the peptide hormone arginine vasopressin (AVP), which exerts its effects through the type 2 vasopressin receptor (AVPR2). Disrupted function or regulation of AQP2 or the AVPR2 results in nephrogenic diabetes insipidus (NDI), a common clinical condition of renal origin characterized by polydipsia and polyuria. Over several years, major research efforts have advanced our understanding of NDI at the genetic, cellular, molecular, and biological levels. NDI is commonly characterized as hereditary (congenital) NDI, arising from genetic mutations in the AVPR2 or AQP2; or acquired NDI, due to for exmple medical treatment or electrolyte disturbances. In this article, we provide a comprehensive overview of the genetic, cell biological, and pathophysiological causes of NDI, with emphasis on the congenital forms and the acquired forms arising from lithium and other drug therapies, acute and chronic renal failure, and disturbed levels of calcium and potassium. Additionally, we provide an overview of the exciting new treatment strategies that have been recently proposed for alleviating the symptoms of some forms of the disease and for bypassing G protein-coupled receptor signaling.

Tubulointerstitial nephritis is a common cause of kidney failure and may have diverse etiologies. This form of nephritis is sometimes associated with autoimmune disease, but the role of autoimmunemechanisms in disease development is not well understood. Here, we present the cases of three patients with autoimmune polyendocrine syndrome type 1 who developed tubulointerstitial nephritis and ESRD in association with autoantibodies against kidney collecting duct cells. One of the patients developed autoantibodies targeting the collecting duct-specificwater channel aquaporin 2, whereas autoantibodies of the two other patients reacted against the HOXB7 or NFAT5 transcription factors, which regulate the aquaporin 2 promoter. Our findings suggest that tubulointerstitial nephritis developed in these patients as a result of an autoimmune insult on the kidney collecting duct cells.

This paper presents an effective framework for real-time reconfiguration of a multi-camera active-vision system performing surveillance of articulated objects with time-varying geometries. The proposed novel real-world strategy tangibly improves surveillance performance by selecting near-optimal viewpoints along a prediction time horizon in order to maximize visibility of a human form in the presence of multiple, dynamic obstacles. Controlled experiments have demonstrated a positive relationship between system re-configurability and surveillance performance.

Objectives: To quantify changes in abundance of sodium transporters [Na-Cl cotransporter (NCC), its phosphorylated form (pNCC), Na-K-Cl cotransporter (NKCC2) and epithelial sodium channel g-subunit (g-ENaC)] and prostasin in urinary exosomes in response to mineralocorticoid administration and oral salt loading, and explore associations with plasma aldosterone (aldo) and K+, in patients undergoing fludrocortisone suppression testing (FST).Methods: Baseline (D0) and day 4 (D4) morning urine samples were collected from 13 patients, including 10 with hypertension and raised aldo/renin ratio undergoing FST to confirm or exclude primary aldosteronism (PA; confirmed in 9) and 3 cured of PA by unilateral adrenalectomy. Urinary exosomes were isolated by ultracentrifugation and analysed by immunoblotting.Results: Increases in abundance of NCC (1.48 fold, p = 0.03) and pNCC (1.52 fold, p = 0.04) and trends towards increases in prostasin (p = 0.07), NKCC2 (p = 0.09) and cleaved g-ENaC (p = 0.11) were observed among the 13 subjects after 4 days FST. Abundance of cleaved g-ENaC rose significantly (p = 0.02) in the 10 non-operated subjects. Among the 13 subjects, D0 aldo and K+ did not correlate significantly with abundance of the target proteins, although D0 pNCC showed a trend towards positive correlation with aldo (p = 0.09). In the 10 non-operated subjects, D0 pNCC showed a negative correlation with plasma K+ that almost reached significance (p = 0.06).Conclusion: FST is associated with significant increases in NCC and pNCC and trends towards increases in ENaC, prostasin and NKCC2. The negative correlation between baseline plasma K+ and abundance of pNCC observed in adrenal-intact subjects suggests a possible role for K+ in the regulation of tubular salt handling and blood pressure.

This paper presents the effects of the convergent-filamentary die geometry on the volume expansion behaviors of extruded PS foams blown with supercritical CO2. Three groups of interchangeable convergent-filamentary dies were designed to thoroughly represent the die parameters. The experimental results reveal that the die geometry affects volume expansion of the extruded foams through its influences on the die pressure, the pressure-drop rate, and the amount of premature cell growth inside a convergent-filamentary die. Compared with the constant pressure-drop rate for a straight die, the pressure-drop rate for a convergent die increases along the die land, which is favorable for promoting cell nucleation and suppressing premature cell growth. Although the convergent shape is favorable for volume expansion, foams with a low expansion ratio were produced for those dies with a low pressure and a low pressure-drop rate because of the promoted premature cell growth.

Many transgenic and knockout mouse models with increased urine flow have been noted to have structural abnormalities of the renal pelvis and renal inner medulla. Here, we describe an approach for in vivo study of such abnormalities in mice using high resolution contrast enhanced T1-weighted magnetic resonance imaging (MRI). The studies were carried out in mice in which the UT-A isoform 1 and 3 urea transporters had been deleted (UT-A1/3-/- mice). The experiments revealed three distinct variations in the appearance of the renal pelvis in these mice: 1) normal kidneys with no accumulation of contrast agent in the renal pelvis; 2) frank right-sided unilateral hydronephrosis with marked atrophy of the renal medulla, seen relatively infrequently; and 3) a renal pelvic reflux pattern characterized by the presence of contrast agent in the renal pelvis surrounding the renal inner medulla, with no substantial atrophy of the renal medulla, seen in most UT-A1/3-/- mice with advancing age. The reflux pattern was also found in aquaporin-1 knockout mice. UT-A1/3-/- mice also manifested increased mean arterial pressure. Feeding the UT-A1/3-/- mice a low protein diet did not prevent the demonstrated abnormalities of the renal pelvis. These studies demonstrate the feasibility of real time imaging of renal pelvic structure in genetically manipulated mice, providing a tool for non-destructive, temporal studies of kidney structure.

BACKGROUND. Bortezomib is active in heavily pretreated multiple myeloma patients; the dose-limiting toxicity is peripheral neuropathy (PN). METHODS. The authors retrospectively reviewed the incidence, severity, and risk factors for PN in 78 patients who received bortezomib. The median age was 57 years (range, 33–80 years), 62% of patients were men, and 37% of patients were African Americans. Seventeen patients (22%) had diabetes mellitus (DM), and 66 patients (85%) had received thalidomide. Before bortezomib treatment, 37% of the patients reported subjective, grade 1 or 2 PN. Patients received bortezomib alone (n = 10 patients) plus dexamethasone (n = 36 patients) and thalidomide (n = 20 patients) or chemotherapy (n = 12 patients). PN affected 52% of patients, including grade 3 and 4 PN in 15% and 7%, respectively. RESULTS. Twelve patients stopped bortezomib because of side effects that included PN (n = 9 patients), diarrhea (n = 2 patients) and cytomegalovirus pneumonia (n = 1 patient); 11 patients had dose reductions because of PN. Grade 4 PN affected 6 patients (sensory, n = 4 patients; motor/sensory, n = 2 patients). The onset of grade 4 PN was sudden rather than cumulative. Factors that were predictive of PN grade were baseline PN (P = .002), prior thalidomide use (P = .03), and the presence of DM (P = .03). Multiple myeloma responses included complete, near complete, and partial responses in 5% of patients, 10% of patients, and 27% of patients, respectively. Responses were independent of PN and of whether bortezomib was combined with chemotherapy or thalidomide. Patients remained on therapy longer for a median of 5 cycles (range, 2–36 cycles) when they received bortezomib plus thalidomide versus 3 cycles (range, 1–19 cycles) for the other combinations. PN therapy was mostly supportive. It was noteworthy that 6 of 9 patients with PN who received lenalidomide as salvage therapy after bortezomib had significant improvement in their symptoms. CONCLUSIONS. The risk of bortezomib-related PN was greater in patients who had PN and DM at baseline. The authors concluded that an unexpected, symptomatic improvement of PN on lenalidomide is worth further investigation. Cancer 2007. © 2007 American Cancer Society.

Background In preclinical studies, bortezomib was shown to suppress tumor growth, sensitize malignant cells to apoptosis, and reverse chemotherapy resistance. Patients and Methods We evaluated the addition of escalating doses of bortezomib 0.7, 1, and 1.3 mg/m 2 intravenously on days 1, 4, and 8 to DT-PACE (cisplatin 10 mg/m 2 , doxorubicin 10 mg/m 2 , cyclophosphamide 400 mg/m 2 , and etoposide 40 mg/m 2 per day by intravenous continuous infusion on days 1-4) plus oral dexamethasone 40 mg on days 1-4 and thalidomide 200 mg on days 1-8 in newly diagnosed patients with multiple myeloma. Peripheral blood stem cells were collected after cycle 1. Twelve patients completed the study, and all received autologous stem cell transplantation (SCT). Results Hematologic toxicities were predictable, with 3 episodes of neutropenic fever. Grade ≥ 2 nonhematologic toxicities included diarrhea (n = 1), deep vein thrombosis (n = 2), hypotension (n = 2), syncope (n = 1), and peripheral neuropathy (n = 3). The median number of CD34 + cells collected was 20.57 × 10 6 CD34 + cells/kg. After 2 cycles, 10 of 12 patients exhibited a partial response or better. Best response after autologous SCT, complete response/near complete response was exhibited in 9 patients, and partial response was exhibited in 3 patients. At a median of 20 months, 4 patients experienced relapse and 1 had died. Bortezomib/DT-PACE compared favorably with DT-PACE with regard to leukapheresis days, total CD34 + cell collection, and engraftment. Conclusion This novel strategy of simultaneous proteasome inhibition in combination with thalidomide and chemotherapy was effective and safe, allowing for adequate stem cell collection and early autologous SCT; its impact on overall survival, especially in patients with high-risk myeloma, awaits further investigation.

PurposeBcl-2 regulates the mitochondrial apoptosis pathway that promotes chemotherapy resistance. Bcl-2 antisense oligonucleotide, G3139, targets Bcl-2 mRNA.Patients and MethodsG3139 was administered (3 to 7 mg/kg/d for 7 days) by continuous intravenous infusion. On day 4, patients started thalidomide (100 to 400 mg as tolerated) and dexamethasone (40 mg daily for 4 days) on 21-day cycles for three cycles. Stable and responding patients continued on 35-day cycles for 2 years.ResultsThirty-three patients (median age, 60 years; range, 28 to 76 years) received 220 cycles. Patients received a median of three prior regimens including thalidomide (n = 15) and stem-cell transplantation (n = 31). The regimen was well tolerated; the median number of cycles per patient was eight (range, one to 16+ cycles). Toxicities included reversible increase in creatinine, thrombocytopenia, neutropenia, fatigue, anorexia, constipation, fever, neuropathy, edema, electrolyte disturbances, and hyperglycemia. Fifty-five percent of patients had objective responses, including two complete responses (CRs), four near CRs (positive immunofixation), and 12 partial responses; six patients had minimal responses (MRs). Of patients who received prior thalidomide, seven had objective responses, and three had MRs. The median duration of response was 13 months, and estimated progression-free and overall survival times were 12 and 17.4 months, respectively. Responding patients had significant increase in polyclonal immunoglobulin M (P = .005), indicating innate immune system activation. Western blot analysis of Bcl-2 protein isolated from myeloma cells before and after G3139 demonstrated a decrease of Bcl-2 levels in three of seven patients compared with six of nine patients using reverse transcriptase polymerase chain reaction.ConclusionG3139, dexamethasone, and thalidomide are well tolerated and result in encouraging clinical responses in relapsed multiple myeloma patients.

Purpose: Inosine monophosphate dehydrogenase (IMPDH) inhibitors have been used to induce leukemia blast cell differentiation but have not been tested in multiple myeloma for activity. Currently, available IMPDH inhibitor, mycophenolate mofetil (MMF), which is known as an immunosuppressant, was shown to induce apoptosis in myeloma cell lines. On the basis of our preclinical studies, we designed a clinical study to test our hypothesis that MMF has antimyeloma activity. Experimental Design: A Phase I MMF dose escalation study was conducted in relapsed and refractory myeloma patients who had documented disease progression by myeloma markers or bone marrow plasmacytosis to determine the maximum tolerated dose, toxicities, and efficacy of the drug. To assess the activity of IMPDH inhibition in the myeloma cells of patients, we measured intracellular nucleotide triphosphate levels by high-performance liquid chromatography-based analysis and examined the correlation with clinical response. Results: Among the 11 study patients, MMF was generally well tolerated and was administered up to a maximum dose of 5g/day. The most common toxicity was grade 1 fatigue (n = 4, 36%). One patient had a partial response (3g/day), four patients had stable disease, and six patients had progression of disease. There was a statistically significant difference in the intracellular dGTP level changes between the stable disease/partial response group versus progression of disease. Conclusions: MMF at 1 to 5 g/day daily dose is well tolerated by patients with relapsed and refractory multiple myeloma patients. Positive correlation between clinical response and depletion of intracellular dGTP level was shown. Future drug development to target this enzyme maybe useful in treating myelomas.

Relapse remains a major cause of treatment failure after autotransplantation (auto-PBSCT) for Hodgkin's disease (HD). The administration of non-crossresistant therapies during the post-transplant period may delay or prevent relapse. We prospectively studied the role of consolidation chemotherapy (CC) after auto-PBSCT in 37 patients with relapsed or refractory HD. Patients received high-dose gemcitabine-BCNU-melphalan and auto-PBSCT followed by involved-field radiation and up to four cycles of the DCEP-G regimen, which consisted of dexamethasone, cyclophosphamide, etoposide, cisplatin, gemcitabine given at 3 and 9 months post transplant alternating with a second regimen (DPP) of dexamethasone, cisplatin, paclitaxel at 6 and 12 months post transplant. The probabilities of event-free survival (EFS) and overall survival (OS) at 2.5 years were 59% (95% CI=42-76%) and 86% (95% CI=71-99%), respectively. In all, 17 patients received 54 courses of CC and 15 were surviving event free (2.5 years, EFS=87%). There were no treatment-related deaths during or after the CC phase. Post-transplant CC is feasible and well tolerated. The impact of this approach on EFS should be evaluated in a larger, randomized study.

A novel method for online, robotic interception of moving objects using visual feedback is proposed in this paper. No prior knowledge of the motion of the object is assumed. Since such objects might depart quickly from the workspace of the robot, fast interception is a critical issue. Thus, a novel time-optimal rendezvous-guidance technique that takes the dynamic limitations of the robot into account has been developed. In the proposed methodology, first, a parallel-navigation rule, originally introduced in the missile-guidance literature, is applied to generate a set of instantaneous task-space velocity commands, which, if executed, would keep the end-effector on a collision course with the object. Subsequently, a rendezvous-guidance method is utilized to reduce the original command set to one with velocity-matching capability. Finally, the fastest velocity command in the reduced set is chosen such that the dynamic limitations of the actuators of the robot are not violated. The proposed algorithm results in a fast and robust interception as shown by several simulation examples in 2D and 3D workspace.

Disease relapse occurs in 50% or more of patients who are autografted for relapsed or refractory lymphoma (NHL) or Hodgkin's disease (HD). The administration of non-cross-resistant therapies during the post-transplant phase could possibly control residual disease and delay or prevent its progression. To test this approach, 55 patients with relapsed/refractory or high-risk NHL or relapsed/refractory HD were enrolled in the following protocol: stem cell mobilization: cyclophosphamide (4.5 g/m2) + etoposide (2.0 g/m2) followed by GM-CSF or G-CSF; high-dose therapy: gemcitabine (1.0 g/m2) on day −5, BCNU (300 mg/m2) + gemcitabine (1.0 g/m2) on day −2, melphalan (140 mg/m2) on day −1, blood stem cell infusion on day 0; post-transplant immunotherapy (B cell NHL): rituxan (375 mg/m2) weekly for 4 weeks + GM-CSF (250 μg thrice weekly) (weeks 4–8); post-transplant involved-field radiotherapy (HD): 30–40 Gy to pre-transplant areas of disease (weeks 4–8); post-transplant consolidation chemotherapy (all patients): dexamethasone (40 mg daily)/cyclophosphamide (300 mg/m2/day)/etoposide (30 mg/m2/day)/cisplatin (15 mg/m2/day) by continuous intravenous infusion for 4 days + gemcitabine (1.0 g/m2, day 3) (months 3 + 9) alternating with dexamethasone/paclitaxel (135 mg/m2)/cisplatin (75 mg/m2) (months 6 + 12). Of the 33 patients with B cell lymphoma, 14 had primary refractory disease (42%), 12 had relapsed disease (36%) and seven had high-risk disease in first CR (21%). For the entire group, the 2-year Kaplan–Meier event-free survival (EFS) and overall survival (OS) were 30% and 35%, respectively, while six of 33 patients (18%) died before day 100 from transplant-related complications. The rituxan/GM-CSF phase was well-tolerated by the 26 patients who were treated and led to radiographic responses in seven patients; an eighth patient with a blastic variant of mantle-cell lymphoma had clearance of marrow involvement after rituxan/GM-CSF. Of the 22 patients with relapsed/refractory HD (21 patients) or high-risk T cell lymphoblastic lymphoma (one patient), the 2-year Kaplan–Meier EFS and OS were 70% and 85%, respectively, while two of 22 patients (9%) died before day 100 from transplant-related complications. Eight patients received involved field radiation and seven had radiographic responses within the treatment fields. A total of 72 courses of post-transplant consolidation chemotherapy were administered to 26 of the 55 total patients. Transient grade 3–4 myelosuppression was common and one patient died from neutropenic sepsis, but no patients required an infusion of backup stem cells. After adjustment for known prognostic factors, the EFS for the cohort of HD patients was significantly better than the EFS for an historical cohort of HD patients autografted after BEAC (BCNU/etoposide/cytarabine/cyclophosphamide) without consolidation chemotherapy (P = 0.015). In conclusion, post-transplant consolidation therapy is feasible and well-tolerated for patients autografted for aggressive NHL and HD and may be associated with improved progression-free survival particularly for patients with HD. Bone Marrow Transplantation (2002) 29, 303–312. doi:10.1038/sj.bmt.1703363

An important task for autonomous industrial robotic systems is the interception of moving objects. In order to achieve this objective, an on-line robot-motion planning technique that utilizes real-time sensory feedback about the object's motion is needed. In this paper, an Ideal Proportional Navigation Guidance (IPNG) based technique is utilized for on-line robot-motion planning. One must note, however, that navigation-guidance techniques were originally developed for bringing the interceptor into a collision course with (hostile) airborne targets. Therefore, in our case, a conventional tracking technique must be utilized as a subsequent phase to an initial IPNG-based robot-motion planning phase in order to ensure smooth interception. The implementation of the hybrid scheme in industrial settings, where one may not have access to the robot's dynamic model nor to the joints' controllers, is discussed. Real-time experimental results using an industrial robot and a computer-vision system are presented, confirming the (interception-time) superiority of our proposed scheme over conventional tracking techniques.

AIM: To quantify changes in urinary excretion of aquaporin2 water channels (u-AQP2), the sodium-potassium-chloride co-transporter (u-NKCC2) and the epithelial sodium channels (u-ENaC) during treatment with bendroflumethiazide (BFTZ), amiloride and placebo.METHODS: In a randomized, double-blinded, placebo-controlled, 3-way crossover study we examined 23 healthy subjects on a standardized diet and fluid intake. The subjects were treated with amiloride 5 mg, BFTZ 1.25 mg or placebo twice a day for 4.5 d before each examination day. On the examination day, glomerular filtration rate was measured by the constant infusion clearance technique with (51)Cr-EDTA as reference substance. To estimate the changes in water transport via AQP2 and sodium transport via NKCC2 and ENaC, u-NKCC2, the gamma fraction of ENaC (u-ENaCγ), and u-AQP2 were measured at baseline and after infusion with 3% hypertonic saline. U-NKCC2, u-ENaCγ, u-AQP2 and plasma concentrations of vasopressin (p-AVP), renin (PRC), angiotensin II (p-ANG II) and aldosterone (p-Aldo) were measured, by radioimmunoassay. Central blood pressure was estimated by applanation tonometry and body fluid volumes were estimated by bio-impedance spectroscopy. General linear model with repeated measures or related samples Friedman's two-way analysis was used to compare differences. Post hoc Bonferroni correction was used for multiple comparisons of post infusion periods to baseline within each treatment group.RESULTS: At baseline there were no differences in u-NKCC2, u-ENaCγ and u-AQP2. PRC, p-Ang II and p-Aldo were increased during active treatments (P < 0.001). After hypertonic saline, u-NKCC2 increased during amiloride (6% ± 34%; P = 0.081) and increased significantly during placebo (17% ± 24%; P = 0.010). U-AQP2 increased significantly during amiloride (31% ± 22%; P < 0.001) and placebo (34% ± 27%; P < 0.001), while u-NKCC2 and u-AQP2 did not change significantly during BFTZ (-7% ± 28%; P = 0.257 and 5% ± 16%; P = 0.261). U- ENaCγ increased in all three groups (P < 0.050). PRC, AngII and p-Aldo decreased to the same extent, while AVP increased, but to a smaller degree during BFTZ (P = 0.048). cDBP decreased significantly during BFTZ (P < 0.001), but not during amiloride or placebo. There were no significant differences in body fluid volumes.CONCLUSION: After hypertonic saline, u-NKCC2 and u-AQP2 increased during amiloride, but not during BFTZ. Lower p-AVP during BFTZ potentially caused less stimulation of NKCC2 and AQP2 and subsequent lower reabsorption of water and sodium.

Information obtained through the analysis of dynamic manipulability can be useful in the design and control of robotic manipulators. In this paper, we investigate the influences of the joint drive systems on the dynamic manipulability, with special attention to the effects of gear reduction ratios. In order to reflect this influence, a new form of the dynamic manipulability ellipsoid is developed, which includes the gear reduction ratios, and a modified formula is derived for the dynamic manipulability measure. This formula indicates that joint drive dynamics can significantly influence the dynamic manipulability of a robot. The most important effect is that changing the gear reduction ratios modifies the nature of the dynamic manipulability distribution throughout the workspace of the manipulator. Examples of a two-link planar arm and a PUMA 560 robot are presented to illustrate the results.

This article describes the emerging roles of the systems engineering (SE) function in supporting enterprise management in information-intensive organizations. “Enterprise Systems Engineering” (ESE) comprises three major roles or “levels” of systems engineering for successful and efficient development or procurement of large complex systems of systems (SoS). While the authors' experience focuses predominantly on government organizations acting as their own SoS integrators, the SoS ESE concept has generic applicability for any organization, public or private, seeking to attain competitive advantage through leveraging of information technology resources and systems. The processes and tools described here have been developed and successfully employed to facilitate government project management and investment decisions and control. [Carlock and Decker, 1998] This paper describes a formal three-level SoS ESE process that, at the top level, organizes and maintains all of the details of the enterprise-wide SoS architecture and strategic development plan in a flexible framework that accommodates the changes expected over a long SoS evolution. The information maintained in this framework allows the organization to know where it is going, how and when it is going to get there, the required capabilities and interfaces of each SoS component, and the impact of changes to system requirements, budgets, schedules, etc., on the overall SoS. The middle level processes allow the organization to perform trade studies among alternative solutions to implement required capabilities based on what is best for the enterprise-wide SoS rather than just local considerations. The end result of the middle level processes is a selected and approved solution and its associated cost, schedule, benefits, and technical baselines. The third level processes implement the approved solutions in accordance with the approved baselines. © 2001 John Wiley & Sons, Inc. Syst Eng 4: 242–261, 2001

Presents an approach to online, robot-motion planning for moving-object interception. The proposed approach utilizes a navigation-guidance-based technique, that is robust and computationally efficient for the interception of fast-maneuvering objects. Navigation-based techniques were originally developed for the control of missiles tracking free-flying targets. Unlike a missile, however, the end-effector of a robotic arm is connected to the ground, via a number of links and joints, subject to kinematic and dynamic constraints. Also, unlike a missile, the velocity of the robot and the moving object must be matched for a smooth grasp, thus, a hybrid interception scheme, which combines a navigation-based interception technique with a conventional trajectory tracking method is proposed herein for intercepting fast-maneuvering objects. The implementation of the proposed technique is illustrated via numerous simulation examples.

In this paper, a dynamic system consisting of a robot manipulator and a target is analyzed. The target is considered in a general way as a dynamic subsystem having finite mass and moments of inertia (e.g., a rigid body or a second robot). The situation investigated is when the robot establishes interaction with the target in such a way that it intercepts and captures a reference element of the target. The analysis of target capture is divided into three phases in terms of time: the precapture, “free” motion (finite motion); the transition from free to constrained motion in the vicinity of interception and capture (impulsive motion); and the postcapture, constrained motion (finite motion). The greatest attention is paid to the analysis of the phase of transition, the impulsive motion, and dynamics of the system. Based on the use of impulsive constraints and the Jourdainian formulation of analytical dynamics, a novel approach is proposed for the dynamic modeling of target capture by a robot manipulator. The proposed approach is suitable to handle both finite and impulsive motions in a common analytical framework. Based on the dynamic model developed and using a geometric representation of the system’s dynamics, a detailed analysis and a performance evaluation framework are presented for the phase of transition. Both rigid and structurally flexible models of robots are considered. For the performance evaluation analyses, two main concepts are proposed and corresponding performance measures are derived. These tools may be used in the analysis, design, and control of time-varying robotic systems. The dynamic system of a three-link robot arm capturing a rigid body is used to illustrate the material presented.

This paper presents a novel approach to on-line, robot-motion planning for moving-object interception. The proposed approach utilizes a navigation-based technique, which is robust and computationally efficient for the interception of fast-maneuvering objects. Navigation-based techniques were originally developed for the control of missiles tracking free-flying targets. Unlike a missile, however, the end-effector of a robotic arm is connected to the ground, via a number of links and joints, subject to kinematic and dynamic constraints. Also, unlike a missile, the velocity of the robot and the moving object must be matched for a smooth grasp , thus, a hybrid interception scheme, which combines a navigation-based interception technique with a conventional trajectory tracking method is proposed herein for intercepting fast-maneuvering objects. The implementation of the proposed technique is discussed via numerous simulation examples.

“Systems of systems” differ from single systems in the way in which they are implemented and in how their implementation must be controlled. For this reason, the systems engineering processes necessary to ensure successful implementation of systems of systems differ in several important ways from the systems engineering processes typically applied to individual systems. A successful approach to implementing systems of systems requires a multi-tiered set of systems engineering processes that builds upon the traditional single-system approach.

In this paper we investigate the dynamics of robotic interception and capture of a moving object. This problem, i.e., the interception and capture of a moving object by a robot, is called dynamic mass capture. The effects of structural flexibility of the robot is taken into consideration. In terms of time, the analysis is divided into three phases: before capture (finite motion), at the vicinity of interception and capture (impulsive motion), and after capture (finite motion). Special attention is paid to the modeling of the second phase when the robot captures the target and it becomes part of the end effector, thus, the system's degrees of freedom suddenly change. To decribe this event, a novel approach is proposed. This is based on the use of a class of impulsive constraints, the so-called inert constraints. Jourdain's principle is employed to derive the dynamic equations for both finite and impulsive motions. Simulation results are presented for two examples: a single flexible link and a two-link manipulator capturing moving objects. In the example of the single link, the results are compared with the observations of an experiment, and good agreement is found between experimental and simulation results.

A number of active prediction planning and execution (APPE) systems have recently been proposed for robotic interception of moving objects. The cornerstone of such systems is the selection of a robot-object rendezvous-point on the predicted object trajectory. Unlike tracking-based systems, which minimize the state difference between the object and the robot at each control period, in this methodology the robot is sent directly to the selected rendezvous-point. A fine-motion tracking strategy would then be employed for grasping the moving object. Herein, a novel strategy for selecting the optimal (earliest) rendezvous-point is presented. For objects with predictable trajectories, this is a significant improvement over previous APPE strategies which select the rendezvous-point from a limited number of non-optimally chosen candidates.

On-line planning of gross robot motion for moving-object interception is considered in this article within the context of an active prediction planning, and execution (APPE) strategy. The objective is to find an optimal interception point such that the robot end-effector and the object arrive simultaneously at this target pregrasping point. In this approach, the optimality of the selected rendezvous point on the target trajectory is directly dependent on the robot-trajectory planning technique. Thus, for the solution of the general interception problem, three issues must be addressed: (i) optimal rendezvous-point selection, (ii) optimal robot-trajectory planning, and (iii) replanning in response to gross changes in the predicted target trajectory. The effect of uncertainties in the target-trajectory prediction must be considered at each planning stage. Herein, solutions to the first two problems are briefly reviewed as background to the proposed rendezvous-point replanning strategy. This strategy determines when replanning is necessary, modifies the rendezvous point, and iteratively replans robot “patch trajectories” to new interception points. Simulation results using two different on-line robot-motion-generation strategies are also presented. © 1998 John Wiley & Sons, Inc. 15: 97–114, 1998

A novel active prediction, planning, and execution (APPE) system is presented for the robotic interception of moving objects. An APPE system's objective is simply to move the robot to the earliest pregrasping location. A fine-motion tracking algorithm can take over the motion control at that point, utilizing proximity sensors mounted on the robot's end-effector. This approach eliminates the necessity of tracking the motion of the object, as required by conventional tracking-based techniques, where the distance between the robot's end-effector and the object is reduced continuously. In this paper, the proposed APPE system is first briefly introduced, and its individual modules are then discussed in detail. Simulation and experimental results are presented in support of the developed optimal-interception strategy.

We performed a prospective, randomized study to determine whether subcutaneous administration of interleukin-2 (IL-2) in combination with an autologous renal cell vaccine is feasible and can potentiate antitumor immunity. Seventeen patients with metastatic renal cell carcinoma underwent surgical resection with preparation of an autologous tumor cell vaccine. Patients were vaccinated intradermally twice at weakly intervals with 10(7) irradiated tumor cells plus bacillus Calmette-Guérin, and once with 10(7) tumor cells alone. Patients were randomized to one of three groups: no adjuvant IL-2, low-dose IL-2 (1.2 x 10(6) IU/m2), or high-dose IL-2 (1.2 x 10(7) IU/m2). IL-2 was administered subcutaneously on the day of vaccination and the subsequent 4 days. Immune response was monitored by delayed-type hypersensitivity (DTH) response to tumor cells as compared with normal autologous renal cells. Sixteen of 17 patients received vaccine therapy. Four patients developed cellular immunity specific for autologous tumor cells as measured by DTH responses; two had received no IL-2 and two had received high-dose IL-2. There were two partial responses (PR) noted, both in patients who received high-dose IL-2. One responding patient was DTH(+) and one was negative. A third patient who was DTH(+) after vaccination with no IL-2 had a dramatic PR after receiving IL-2 subcutaneously in a subsequent protocol. Prospective testing of response to recall antigens indicated that only 5 of 12 tested patients were positive, including both clinical responders. These data suggest that subcutaneously administered adjuvant IL-2 does not dramatically augment the immunologic response to autologous renal cell vaccines as determined by the development of tumor-specific DTH response.

PURPOSE Although high-dose interleukin-2 (IL-2) can produce durable remissions in a subset of responding patients with renal cell carcinoma (RCC), this occurs in the setting of significant toxicity. The purpose of this study is to define the maximum-tolerated dosage (MTD) of IL-2 and interferon alfa-2a (IFN alpha-2a) that can be administered chronically on an outpatient basis. PATIENTS AND METHODS Fifty-three patients with advanced cancer of variable histology with good prognostic features were treated in six cohorts. Patients in cohorts one through five received IL-2 (1.5 or 3.0 x 10(6) million units (mU)/m2) Monday through Friday and IFN alpha-2a (1.5 or 3 x 10(6) mU/m2) daily for a 4-week cycle. In cohort six, IFN alpha-2a was given three times a week. Immunologic monitoring, including serum levels of soluble IL-2 receptor (sIL-2R) and neopterin, flow cytometry, and natural killer cell (NK) activity, were measured. Patients were evaluated for toxicity, response, and survival. RESULTS Almost all patients developed grade I/II toxicities commonly associated with cytokine therapy. Symptoms were most severe with the first treatment of each week. Dose-limiting toxicities included grade III fatigue, hypotension, and creatinine elevations. The MTD was 1.5 mU/m2 daily x 5 given subcutaneously repeated weekly for IL-2 and 1.5 mU/m2 daily subcutaneously (dose level 3) for IFN. Six of 25 assessable patients with RCC (24%) achieved a partial response (PR), including four of eight patients who were previously untreated. There were no objective responses in patients with other tumors, including 12 melanoma patients. CONCLUSION IL-2 and IFN alpha-2a can be given with tolerable toxicities on an outpatient basis and shows significant activity in patients with metastatic RCC.