Rehabilitation interventions for cancer survivors: The influence of context

BACKGROUND

Today more and more people survive cancer. Cancer survivors need help to recover both from the cancer and the treatment. Rehabilitative interventions have been set up to meet their needs. However, there are studies that report no major effects following careful, targeted intervention. Furthermore, it seems difficult to define whether an effect is caused by the intervention or whether it is due to contextual parameters such as human interactions, the organisation, the staff, the physical surroundings or the general atmosphere. The present study examines the influence of three contextual parameters in rehabilitation courses for cancer survivors in Denmark.

METHODS

The study was based on an ethnographic fieldwork with participant observation at nine week-long courses, on in-depth interviews and on written sources. Fieldwork is well-suited for studying interventions in context, such as social interactions between people and their physical, material and institutional surroundings. The analysis is based on Duranti's and Goodwin's theoretical approach to context.

RESULTS

The findings are categorised into three contextual parameters. The setting, including its aesthetic value, its physical surroundings and the scheduling of the courses. The behavioural environment, which comprised work commitment and the care provided by the staff. The language environment insofar as it facilitated a sense of community.

DISCUSSION

The results demonstrate the influence of contextual parameters not formalised in the intervention programme. Contexts affect the outcome of an intervention because they frame and inform the teaching, communication and various forms of social gathering. The study suggests that the effects of the intervention as measured by quantitative studies cannot be properly interpreted without taking into account the context within which the intervention is embedded.

How cancer survivors experience their changed body encountering others

BACKGROUND

Psychosocial cancer research illustrates how women treated for breast cancer experience physical changes in their bodies and the way they perceive, that, others see their body. But how patients with other types of cancer have experienced changes in their bodies and how this affects their relationship with others is less researched.

OBJECTIVES

To explore how cancer survivors with different types of cancer and cancer treatment, experience and handle their changed body, especially when meeting others, and how this influences their everyday life of survivorship, i.e. long after treatment has been completed.

METHODS

Participant observation at a Cancer Rehabilitation Centre (CRC). Of the observed participants 23 were selected and interviewed twice.

RESULTS

Many participants had a changed body due to the cancer and its treatment. When the cancer survivors meet others they experience that their changed body means that they are avoided, looked at in specific ways, or greeted with a specific compliment. The verbal and nonverbal language that the cancer survivors are met with indicates the existence of a specific discursive aesthetic in relation to the disease and the changed body. This discursive aesthetic represents a silence and secrecy about cancer, which makes it impossible for survivors to talk about their experiences with cancer and a changed body.

CONCLUSION

The changed body not only represents the physical sign of cancer, it also represents the social presence and representation of cancer. The analysis gives an insight into general questions of meaning related to the changed body in late modernity.

Cancer rehabilitation in Denmark: the growth of a new narrative

A fundamental assumption behind cancer rehabilitation in many Western societies is that cancer survivors can return to normal life by learning to deal with the consequences of their illness and their treatment. This assumption is supported by increasing political attention to cancer rehabilitation and a growth in residential cancer-rehabilitation initiatives in Denmark (Danish Cancer Society 1999; Government of Denmark 2003). On the basis of their ethnographic fieldwork in residential-cancer rehabilitation courses, the authors examine the new rehabilitation discourse. They argue that this discourse has challenged the dominant illness narrative, "sick-helped-cured," producing a new narrative, "sick-helped-as if cured," and that this new narrative is produced and reproduced through technologies of power and of the self.

Marked bodies and selves: a literary-semiotic perspective on breast cancer and identity

A diagnosis of breast cancer is not just life-threatening but often also disfiguring. Breast cancer research has pointedly focused on the connection between bodily loss and loss of self. We will examine the narratives of two Danish women who have been treated for breast cancer and are dealing with the consequences of their treatment. Drawing upon theories of phenomenology and literary-semiotics we demonstrate how the women are negotiating their identities. In narratives of breast cancer bodily practices play a prominent role in helping or hindering the re-construction of identity. We will focus on breast reconstruction as a bodily practice and seek to understand how and why breast cancer survivors either accept or reject the possibility of reconstructing their identity through breast reconstruction. We suggest that the literary-semiotic concept of marking can lead to a broader understanding of the connection between illness, body and identity. Breast reconstruction and the refusal of breast reconstruction can be viewed as part of a semiotic monitoring and marking of the body that can take place in the aftermath of treatment for breast cancer.

Long-term prevention of diabetic nephropathy: an audit

AIMS/HYPOTHESIS

In type 1 diabetic patients with microalbuminuria not receiving antihypertensive treatment, an increase in urinary AER (UAER) of 6-14%/year and a risk of developing diabetic nephropathy (DN) of 3-30%/year have been reported. We audited the long-term effect of blocking the renin-angiotensin-aldosterone system (RAAS) with an ACE inhibitor (ACEI) or angiotensin II receptor blocker (ARB) in microalbuminuric type 1 diabetic patients on progression of microalbuminuria and development of DN.

METHODS

All patients with type 1 diabetes and persistent microalbuminuria (30-300 mg/24 h) were identified (n=227) in 1995 at Steno Diabetes Center and followed for 11 years. Development of DN was defined as a UAER of >300 mg/24 h in two of three consecutive urine samples.

RESULTS

Age and duration of diabetes at baseline (mean+/-SD) were 46+/-15 and 28+/-13 years, respectively. During follow-up 14 patients emigrated and 58 (26%) died. Over the same period 79% were treated with an ACEI or ARB. There was a mean decline in UAER of 4%/year. Sixty-five patients (29%) progressed to overt DN, corresponding to 3.1%/year. However, 29 of them regressed to normo- or microalbuminuria on intensified antihypertensive treatment. Glycaemic control and blood pressure remained nearly unchanged.

CONCLUSIONS/INTERPRETATION

In our outpatient clinic, the implementation of RAAS-blocking treatment in type 1 diabetic patients with microalbuminuria successfully reduced long-term progression to overt DN to a rate similar to those previously reported in randomised, double-blind intervention trials of shorter duration using RAAS blockade.

[Hand hygiene--is it really that difficult?]

This paper addresses the apparent discrepancy between knowledge of infection control guidelines--in particular concerning hand hygiene--and the lack of compliance by health care workers. Several factors are involved, including the personal experiences of the single person and the group of staff members--the authentic knowledge. This must be taken into consideration when preparing guidelines, which should reflect daily work situations in health care.

Preventing diabetic nephropathy: an audit

In type 1 diabetic patients with microalbuminuria not receiving antihypertensive treatment, an increase in urinary albumin excretion rate (AER) of 6% to 14%/year and a risk for the development of diabetic nephropathy of 3% to 30%/year have previously been reported. The aim of the present study was to audit the effect of angiotensin converting enzyme (ACE) inhibition on the progression of microalbuminuria and development of diabetic nephropathy. We consecutively identified 227 type 1 diabetic patients with persistent microalbuminuria (urinary AER between 30 and 300mg/24h, ELISA). According to the level (> or = 100 or < 100mg/24 h) and/or rate of progression in urinary AER (>6% or < or =6%/year), patients were divided into a high-risk group (n= 177) and a low-risk group (n= 50) for development of diabetic nephropathy. According to international guidelines, all patients at high-risk were recommended ACE-inhibitor treatment. Throughout the study, 67% of the patients were treated with an ACE inhibitor. Urinary AER significantly declined by 8.3%/year (95% CI: 2.8 to 13.9) in the whole group of patients, and the risk for the development of diabetic nephropathy during follow-up was 3.5%/year. Glycaemic control and blood pressure remained unchanged during the study. The implementation of modified international guidelines regarding the use of ACE inhibition in the treatment of microalbuminuric type 1 diabetic patients reduced progression to diabetic nephropathy comparable to what has previously been reported in intervention trials.

Long-term beneficial effect of ACE inhibition on diabetic nephropathy in normotensive type 1 diabetic patients

BACKGROUND

The purpose of this study was to assess whether long-term (8 years) inhibition of angiotensin-converting enzyme (ACE) protects kidney function in normotensive type 1 diabetic patients with diabetic nephropathy.

METHODS

We performed an open randomized follow-up study of normotensive type 1 diabetics with nephropathy either treated (N = 15) or not (N = 17) with captopril twice per day (average 74, range 12.5 to 125 mg/day). The main outcome measures were arterial blood pressure, albuminuria, and glomerular filtration rate (GFR; 51Cr-EDTA plasma clearance, twice yearly).

RESULTS

Arterial blood pressure (mm Hg) was kept constant in the captopril group, at baseline (mean, SEM), 128/78 (3/2) and during follow-up 129/77 (4/1) but increased significantly in the control group from 127/79 (2/1) to 137/84 (5/2) (P < 0.01). Furthermore, 8 out of the 17 control subjects required treatment with blood pressure-lowering drugs because they developed hypertension. The fractional albumin clearance (x10-5) remained unchanged in the captopril group: baseline [10.8 (1.25) geometric mean and antilog (SEM)] during the eight years [11.8 (1.47)], while a significant rise occurred in control patients: 13.3 (1.23) to 26.2 (1.42) (P < 0.05). Baseline GFR was nearly identical: 111 (6) and 115 (4) mL/min/1.73 m2 in the captopril and control group, respectively. The median (range) rate of decline in GFR (mL/min/year) was 1.7 (10.7 to -2.0) in the captopril group versus 2.8 (17.7 to -2.6) in the control group (P = NS).

CONCLUSIONS

The beneficial effect of captopril in arresting the rise in systemic blood pressure and albuminuria is long lasting. A loss in GFR is minimal in most patients with diabetic nephropathy if normotension is sustained by prospective treatment with ACE inhibitors or restored by implementation of other antihypertensive medications with the development of hypertension.

CD30 shedding from Karpas 299 lymphoma cells is mediated by TNF-alpha-converting enzyme

CD30 is a costimulatory receptor on activated lymphocytes and a number of human lymphoma cells. Specific ligation of membrane-bound CD30 or cellular stimulation by PMA results in a metalloproteinase-mediated down-regulation of CD30 and release of its soluble ectodomain (sCD30). In this report, it is demonstrated that PMA-induced CD30 cleavage from Karpas 299 cells was mediated by a membrane-anchored metalloproteinase which was active on intact cells following 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate extraction of membrane preparations. Moreover, CD30 shedding was blocked by the synthetic hydroxamic acid-based metalloproteinase inhibitor BB-2116 (IC(50), 230 nM) and the natural tissue inhibitor of metalloproteinases (TIMP)-3 (IC(50), 30 nM), but not by the matrix metalloproteinase inhibitors TIMP-1 and TIMP-2. This inhibition profile is similar to that of the TNF-alpha- converting enzyme (TACE) and, indeed, mRNA transcripts of the membrane-bound metalloproteinase-disintegrin TACE could be detected in Karpas 299 cells. The ectodomain of TACE was expressed in bacteria as a GST fusion protein (GST-TACE) which cleaved CD30 from the surface of Karpas 299 cells and concomitantly increased the level of sCD30 in the cell supernatants. Hence, TACE does not only control the release of TNF-alpha, but also that of sCD30.

Lack of impact of low-dose acetylsalicylic acid on kidney function in type 1 diabetic patients with microalbuminuria

OBJECTIVE

High-dose treatment with cyclooxygenase inhibitors reduces urinary albumin excretion rate (AER) in type 1 diabetic patients with microalbuminuria and macroalbuminuria. This effect may lead to an incorrect classification of albuminuria (normo-, micro-, and macroalbuminuria) and jeopardize the monitoring of antiproteinuric treatment (e.g., ACE inhibition). Whether similar difficulties exist using low-dose acetylsalicylic acid (ASA), now widely recommended for primary and secondary prevention of cardiovascular events in type 1 diabetic patients with micro- and macroalbuminuria, remains to be elucidated.

RESEARCH DESIGN AND METHODS

We performed a randomized double-blind crossover trial in 17 type 1 diabetic patients with microalbuminuria (urinary AER 30-300 mg/24 h). Patients were given ASA (150 mg/daily) for 4 weeks followed by placebo for 4 weeks with at least a 2-week washout period in random order. At the end of each treatment period, AER (enzyme-linked immunosorbent assay), glomerular filtration rate (GFR) (plasma clearance of 51Cr-EDTA), blood pressure (BP) (Hawksley), and HbA1c (by high-performance liquid chromatography) were measured. Patients were advised to follow a normal diabetes diet without sodium restriction and received their usual antihypertensive treatment during the investigation.

RESULTS

During the study (ASA vs. placebo), urinary AER (geometric mean 64 [95% CI 39-105] vs. 59 [40-87] mg/24 h), GFR (mean 106 [93-118] vs. 104 [90-117] ml x min(-1) x 1.73 m(-2)), systolic BP (mean 130 [119-141] vs. 130 [119-142] mmHg), diastolic BP (mean 71 [65-78] vs. 71 [64-78] mmHg), and HbA1c (mean 8.4% [8.0-9.0] vs. 8.5% [8.1-9.0]) remained unchanged.

CONCLUSIONS

Treatment with 150 mg ASA daily does not have any impact on AER or GFR in type 1 diabetic patients with microalbuminuria. Consequently, primary and secondary prevention of cardiovascular events with low-dose ASA does not interfere with the classification of AER or monitoring of antiproteinuric treatment in such patients.

Increased sympathetic activity during sleep and nocturnal hypertension in Type 2 diabetic patients with diabetic nephropathy

AIMS

To elucidate the putative factors involved in the blunted nocturnal blood pressure reduction in hypertensive Type 2 diabetic patients with diabetic nephropathy.

METHODS

Extracellular fluid volume and fluid shift from interstitial to plasma volume (haematocrit), sympathetic nervous activity (plasma noradrenaline and adrenaline) and the internal 'body clock' (serum melatonin) were investigated in 31 hypertensive Type 2 diabetes mellitus (DM) patients with diabetic nephropathy (24 males, age 60 (45-73) years). All variables, except extracellular volume, were measured repeatedly with the patients lying awake in bed from 21:30 to 23:00 h (baseline) and during sleep from 23:00 to 07:00 h. Using the median nocturnal blood pressure reduction (8.4%) as a guide, the patients were divided into groups; group 1 with the highest and group 2 with the lowest nocturnal blood pressure reduction.

RESULTS

Haematocrit decreased from baseline to the sleep period in group 1 by a mean (95% confidence interval (CI)) of 1.7 (0.3-3.1)%, but it increased by 0.5 (-1.0-1.9)% in group 2, mean difference (95% CI), -2.1 (-4.0 to -0.2)% (P = 0.029). Noradrenaline decreased from baseline to the sleep period, mean (95% CI), by 13.3 (0.0-25.0)% in group 1 but rose by 7.7 (-9.7-28.4)% in group 2, mean difference (95% CI), -19.6 (-35-0.0)% (P = 0.049). The nocturnal blood pressure change correlated to the nocturnal change in both noradrenaline (r = 0.51, P = 0.004) and haematocrit (r = 0.42, P = 0.018). Adrenaline remained constant in both groups. Extracellular fluid volume and plasma melatonin levels were comparable in the two groups.

CONCLUSION

Sustained adrenergic activity during sleep is associated with blunted nocturnal blood pressure reduction in hypertensive Type 2DM patients with diabetic nephropathy, probably mediated through a lack of peripheral vasodilatation whereas changes in extracellular fluid volume distribution and melatonin secretion have no impact.

Low-protein diet and kidney function in insulin-dependent diabetic patients with diabetic nephropathy

BACKGROUND

Initiation of a low-protein diet (LPD) in patients with various nephropathies induces a faster initial and slower subsequent decline in the glomerular filtration rate (GFR). Whether this initial phenomenon is reversible or irreversible remains to be elucidated.

METHODS

We performed an eight-week prospective, randomized, controlled study comparing the effect of an LPD with a normal-protein diet (NPD) in 29 insulin-dependent diabetic patients with diabetic nephropathy. At baseline, the patients were randomized to either an LPD (0.6 g.kg-1.24 hr-1, LPD group, N = 14) or their NPD (NPD group, N = 15) for four weeks (phase I). Between weeks 4 and 8, all patients received their NPD (phase II, recovery). Dietary protein intake (g.kg-1.24 hr-1), GFR (51Cr-EDTA, ml.min-1.1.73 m-2), albuminuria (enzyme-linked immunoadsorbent assay, mg.24 hr-1), and arterial blood pressure (Hawksley random zero sphygmomanometer, mm Hg) were measured at baseline and after four- and eight-weeks of follow-up. During the investigation, all patients in the LPD group (N = 12) and in the NPD group (N = 14) received their usual antihypertensive treatment.

RESULTS

At baseline, the LPD group and the NPD group were comparable regarding dietary protein intake, GFR, albuminuria, and arterial blood pressure. During phase I, a significant decline in dietary protein intake, GFR, and albuminuria (mean, 95% CI) was observed in the LPD group [0.4 (0.3 to 0.5) g.kg-1.24 hr-1, 8.6 (3.2 to 13.9) ml.min-1.1.73 m-2, and 28.7 (14.0 to 40.9)%, respectively] compared with the NPD group [0.0 (-0.1 to 0.2) g.kg-1.24 hr-1 (P < 0.0001 between diets), 2.5 (-1.8 to 6.8) ml.min-1.1.73 m-2 (P = 0.07 between diets), and 0.0 (-20.1 to 23.5)% (P < 0.05 between diets), respectively]. Conversely, during phase II, a significant increase in dietary protein intake, GFR, and albuminuria [mean, 95% CI; 0.3 (0.2 to 0.5) g.kg-1.24 hr-1, 5.9 (0.8 to 11.1) ml.min-1.1.73 m-2, and 25.0 (4.5 to 49.6)%, respectively] took place in the LPD group compared with the NPD group [0.0 (-0.2 to 0.1) g.kg-1.24 hr-1 (P < 0.0001 between diets), -2.9 (-6.4 to 0.6) ml.min-1.1.73 m-2 (P < 0.01 between diets), and 2.9 (-18.3 to 29.7)% (P = 0.16 between diets), respectively]. Arterial blood pressure was comparable in the two groups of patients during phase I and II.

CONCLUSIONS

Dietary protein restriction for four weeks induces a reversible decline in GFR and albuminuria in insulin-dependent diabetic patients with diabetic nephropathy, whereas systemic blood pressure remains unchanged.

Assessment of glomerular filtration rate in diabetic nephropathy using the plasma clearance of 51Cr-EDTA

Plasma clearance of 51Cr-EDTA is widely used to assess the glomerular filtration rate (GFR) in diabetic nephropathy. Originally, the ratio between the intravenously injected amount of tracer and the total area under the plasma concentration curve was used for the calculation of total 51Cr-EDTA plasma clearance (C(T)). Simplified methods, using the final mono-exponential part of the plasma curve, have been suggested, e.g. four samples, taken 180 to 240 min after injection (C(IV)), or using one sample taken at 240 min (C(I)). Our aim was to evaluate the agreement between measurements of GFR and rate of decline in GFR based upon these three methods. Bland & Altman plots were used to illustrate the range of agreement. We investigated 76 insulin-dependent diabetic (IDDM) patients with microalbuminuria or diabetic nephropathy. GFR was measured after a single intravenous injection of 3.7 MBq 51Cr-EDTA by determining the radioactivity in venous blood samples taken 5, 7, 10, 15, 30, 45, 60, 90, 120, 150, 180, 200, 220, and 240 min after the injection. Rate of decline in GFR was assessed using 12 (6-17) determinations of GFR over a period of time of 8 (4-10) years. Mean (SD) GFRT was 123 (21) ml x min(-1) compared to GFR(IV) 123 (21) ml x min(-1) (NS) and GFR(I) 115 (17) ml x min(-1) (p < 0.00001). The mean difference (95% limits of agreement) between GFR(T) and GFR(IV) was +0.6 (-16.6 to +17.7) ml x min(-1), and between GFR(T) and GFR(I) +8.0 (-6.0 to +22.2) ml x min(-1). The difference between GFR(T) and GFR(I) was significantly correlated with their mean value (r = 0.56, p < 0.00001), indicating increasing underestimation by GFR(I) with increasing GFR levels. The mean (SD) rate of decline in GFR(T) was 2.3 (3.9) ml x min(-1) x year(-1), compared to a mean rate of decline in GFR(IV) of 2.4 (3.6) ml x min(-1) x year(-1) (NS), and a mean rate of decline in GFR(I) of 2.2 (3.5) ml x min(-1) x year(-1) (NS). The mean difference (95% limits of agreement) between rate of decline in GFR(T) and rate of decline in GFR(IV) was +0.16 (-1.59 to +1.91) ml x min(-1) x year(-1), and between rate of decline in GFR(T) and rate of decline in GFR(I) -0.01 (-1.64 to +1.61) ml x min(-1) x year(-1), respectively. In conclusion, our cross-sectional study revealed a close agreement between GFR(T) and GFR(IV) with acceptable limits of agreement (precision), while GFR(I) lacked accuracy. However, a close agreement between rate of decline in GFR(T) and rate of decline in GFR(IV), and between rate of decline in GFR(T) and rate of decline in GFR(I), with acceptable limits of agreement (precision), suggests that both simplified methods are applicable for long-term follow-up.

Characterization, mapping and partial cDNA sequence of the 57-kD intracellular Ki-1 antigen

A novel antigen was identified by the cross-reactivity of the anti-CD30 antibody Ki-1. This 57-kD intracellular Ki-1 antigen (Ki-1/57) is induced upon activation of leukocytes and is transported to the nuclear compartment. We describe the partial cloning and sequencing of the Ki-1/57 cDNA from a lambda gt 11-cDNA library derived from the Hodgkin-analogous cell line L540. New monoclonal antibodies were produced against the recombinant Ki-1/57 protein fragment which were used to confirm that the Ki-1/57 antigen is associated with kinase activity and is expressed in a variety of tumor cell lines and in activated but not resting leukocytes. The Ki-1/57 gene was mapped to the bands 9q22.3-31 of human chromosome 9. This is an area which appears to be associated with secondary chromosomal aberrations in acute myeloid leukemias.

Kidney function after withdrawal of long-term antihypertensive treatment in diabetic nephropathy

Initiation of antihypertensive treatment in hypertensive non-insulin-dependent diabetic (NIDDM) patients with diabetic nephropathy induces a faster initial (0 to 6 months) and slower subsequent (6 months-end) decline in GFR [delta GFR (ml.min-1.1.73 m-2.month-1) approximately 1.5 vs. 0.4]. Whether this initial phenomenon is reversible (hemodynamic) or irreversible (structural damage) after prolonged antihypertensive treatment is not known. To elucidate these mechanisms we investigated 40 hypertensive NIDDM patients (age 61 +/- 7 years, mean +/- SD), known duration of diabetes 14 years (2 to 33 years) [median (range)] with diabetic nephropathy receiving antihypertensive treatment (angiotensin converting enzyme inhibition, N = 30) for 5 years (1 to 20 years). The following variables were measured the last day on antihypertensive treatment and one month after withdrawal of treatment; GFR (51Cr-EDTA), 24-hour arterial blood pressure (24 hr MABP, Takeda TM2420) and albuminuria (ELISA); the mean 24-hour MABP rose from 102 +/- 11 to 111 +/- 10 (P < 0.0001) and albuminuria [geometric mean (antilog SEM)] increased from 634 (1.3) to 1159 (1.2) (P < 0.0001), while GFR (mean +/- SD) remained unchanged (69 +/- 25 to 70 +/- 26 ml.min-1.1.73 m-2, P = 0.21), after withdrawal of antihypertensive treatment. A significant correlation between the relative change in the 24 hour MABP measurement and the relative change in GFR (r = 0.44, P < 0.01) was found. In conclusion, our results suggest that the faster initial decline in GFR after initiating antihypertensive treatment in hypertensive NIDDM patients with diabetic nephropathy is due to a irreversible effect, and should be accounted for when evaluating the beneficial effect of antihypertensive treatment on the progression of diabetic nephropathy in these patients.

Impaired autoregulation of GFR in hypertensive non-insulin dependent diabetic patients

We investigated the effect of acute lowering of blood pressure (BP) upon glomerular filtration rate (GFR) in hypertensive non-insulin-dependent diabetes mellitus (NIDDM) patients, 14 with diabetic nephropathy and 12 with normoalbuminuria. The study was performed twice with the subjects receiving an intravenous injection of either clonidine (150 to 225 micrograms) or saline (0.154 mmol/liter). We assessed GFR, albuminuria, and BP. The two groups were well matched with respect to demographic data, baseline GFR and BP. Clonidine induced similar reductions in mean arterial blood pressure 19 (SE +/- 4) and 21 (SE +/- 3) mm Hg in patients with and without nephropathy, respectively. In the nephropathy group GFR diminished in average from 90 (SE +/- 6) to 81 (SE +/- 7) ml/min/1.73 m2 (P = 0.006), fractional clearance of albumin (x 10(-6)) declined from a geometric mean of 219 (antilog SE /divided by 1.3) to 186 (antilog SE /divided by 1.3) (P = 0.04), and four patients had a complete pressure-passive vasculature, defined as delta GFR% = delta MABP%. A significant correlation between relative reductions in MABP and GFR (r = 0.78, P < 0.001) was demonstrated in albuminuric patients. None of the normoalbuminuric patients had a complete pressure-passive vasculature and there were no significant differences in GFR between the two examinations, but five had abnormal autoregulation of GFR. Mean difference between changes in GFR (95% confidence interval) between the nephropathic and normoalbuminuric group was 5.5 (divided by 2.7 to 13.7) ml/min/1.73 m2 (P = 0.18). Our study suggests that hypertensive NIDDM patients, particularly patients with nephropathy, frequently suffer from impaired or abolished autoregulation of GFR.

Circadian rhythm of arterial blood pressure and albuminuria in diabetic nephropathy

The aim of our study was to evaluate the diurnal relationship between arterial blood pressure and albuminuria, and some potential mechanisms responsible for impaired nocturnal blood pressure reduction (non-dippers, groups I and II) in diabetic nephropathy (DN). Twenty-four-hour ambulatory blood pressure, heart rate (HR) variation (autonomic nervous function) and extracellular fluid volume (ECV) were measured, and urine samples were collected three times during the corresponding day- and nighttimes in 47 insulin-dependent diabetic (IDDM) patients with DN. Mean arterial blood pressure (MABP) during the daytime [mm Hg, median (range)] was identical in group I [105 (96-137)], group II [109 (86-124)] and group III [dippers; average blood pressure reduction from day to night > 10%, 107 (93-132), P = NS], while the nighttime MABP differed [group I, 106 (95-144); group II, 100 (78-118); group III, 91 (76-118); P < 0.001]. No significant difference between the groups concerning the daytime or nighttime albuminuria [microgram/min; median (range)] was observed; [Day: group I, 1467 (235-3933); group II, 695 (170-6719); group III, 875 (228-3173). Night: group I, 1079 (279-4665); group II, 572 (113-3807); group III, 659 (81-2493)]. A significant correlation between MABP and albuminuria was demonstrated during day- (rho = 0.50, P < 0.0005) and nighttime (rho = 0.46, P < 0.005), while neither the absolute nor the relative changes in MABP from day to night correlated significantly with absolute or relative changes in albuminuria from day to night. The night/day ratio of HR was higher in group I [0.93 (0.76-1.09), median (range)] compared to group III [0.83 (0.74-1.02), P < 0.005] and a significant correlation between this ratio and the night/day ratio of MABP was found (rho = 0.54, P < 0.0005). ECV was about the same in the three groups. Our study indicated an association between blood pressure and albuminuria, but the mechanisms involved in the reduction of albuminuria from day to night was not unraveled. A relative lack of sympathetic withdrawal during sleep seems to be an important feature of nocturnal hypertension in diabetic nephropathy.

The acute effect of smoking on systemic haemodynamics, kidney and endothelial functions in insulin-dependent diabetic patients with microalbuminuria

The acute effect of smoking upon arterial blood pressure, urinary albumin excretion rate, glomerular filtration rate and transcapillary escape rate of albumin were investigated in nine normotensive insulin-dependent diabetic patients with microalbuminuria, who had been smoking for 19 (range 4-30) years. In a prospective, open randomized cross-over design, patients were investigated with and without smoking three cigarettes per hour during a 5.5-h period. A rise in systolic blood pressure and heart rate (Takeda TM2420, median (range)) was observed during the smoking day (10(-11 to 14) mmHg and 8 (-1 to 19) beats min-1), compared to the non-smoking day (1 mmHg (-7 to 13) (p = 0.05) and 0 beats min-1 (-2 to 4) (p < 0.01)). Urinary albumin excretion rate (ELISA), glomerular filtration rate (plasma clearance of 51Cr-EDTA) and transcapillary escape rate of albumin (125I-albumin) remained the same with or without smoking. Our study suggests that heavy smoking induces an abrupt rise in systolic blood pressure and heart rate, while vascular leakage of albumin and glomerular filtration rate remain unaltered in normotensive insulin-dependent diabetic patients with microalbuminuria who had been smoking for several years.

A zinc metalloproteinase is responsible for the release of CD30 on human tumor cell lines

The activation marker CD30 is expressed on the cell surface of the malignant cells in Hodgkin's disease and a few non-Hodgkin lymphomas. We have analyzed the regulation of membrane-bound CD30 and found that the binding of a variety of anti-CD30 antibodies induced down-regulation of CD30 on cell lines. In addition, such down-modulation was also observed after treatment of the cell surface proteins with the sulfhydryl reagent iodoacetamide or after stimulation of the second messenger pathway with phorbol ester or calcium ionophore. This modulation was abolished at 4 degrees C and strongly inhibited by chelators like EDTA or 1,10-phenanthroline, whereas EGTA, a selective inhibitor of Ca(2+)-dependent proteinases and other inhibitors of serine, thiol and acid proteinases, showed no effect. The down-modulation was strengthened by Zn2+ or Cd2+, but not by other divalent cations such as Fe2+, Mn2+, Mg2+, Ca2+ or Co2+, thus indicating the involvement of a zinc metalloproteinase in CD30 modulation which can be activated by protein kinase C and by alkylation of sulfhydryl groups. Pulse-chase experiments, analysis of the CD30 glycosylation and specific measurement of the 90-kDa soluble form of CD30 (sCD30) with a sandwich radioimmunoassay revealed that CD30 down-modulation results from enhanced release of 90-kDa sCD30 by the site-specific cleavage of CD30 accomplished by a zinc metalloproteinase. This release occurs at the cell membrane without prior endocytosis.

Increased glomerular filtration rate after withdrawal of long-term antihypertensive treatment in diabetic nephropathy

Initiation of antihypertensive treatment (AHT) in hypertensive insulin-dependent diabetic (IDDM) patients with diabetic nephropathy (DN) induces a faster initial (0 to 6 months) and a slower subsequent (6 months to end of observation) decline in GFR [delta GFR (ml/min/month) approximately 1.5 vs. 0.35]. Whether this initial phenomenon is reversible (hemodynamic) or irreversible (structural damage) after prolonged AHT is not known. To elucidate these mechanisms we investigated 42 hypertensive IDDM patients (16F/26M, age 40 +/- 7 years, mean +/- SD) with DN receiving AHT (angiotensin converting enzyme inhibition, N = 30) for 6 (2 to 15) years [median (range)]. GFR (ml/min/1.73 m2), arterial blood pressure (BP, mm Hg) and albuminuria (mg/24 hr) were measured the last day on AHT and one month after withdrawal of AHT. The measured variables were all significantly elevated after withdrawal of AHT: GFR [mean(SEM)] from 76(4) to 81(4) (P < 0.0001), BP [mean(SEM)] from 140/82 (2/1) to 151/89 (2/1) (P < 0.0005) and albuminuria [geometric mean (antilog SEM)] from 704 (1.2) to 1122 (1.2) (P < 0.0001). A correlation between relative rise in systolic blood pressure (delta Sys%) and relative change in GFR (delta GFR%) was found (r = 0.44, P < 0.005). Our results render some support of the hypothesis that the faster initial decline in GFR is due to a functional (hemodynamic) effect of AHT, which does not attenuate over time, while the subsequent slower decline reflects the beneficial effect on progression of diabetic nephropathy.