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N K Man

Publications and source records attributed to N K Man.

At least 19 recordsLinked to original sources
PubMed1997

Continuous venovenous haemodiafiltration in the acute phase of neonatal maple syrup urine disease.

Maple syrup urine disease results in accumulation of leucine and its metabolites, which may lead in the long term to neurological dysfunction. In acute neonatal crises, large amounts of leucine may be removed by continuous venovenous haemofiltration. This extracorporeal technique has its risks and hazards, which increase with duration of treatment. We report three neonates in life-threatening conditions due to maple syrup urine disease, treated for not more than 12 h with various continuous venovenous techniques: continuous haemofiltration, haemodiafiltration and haemodialysis. The efficiency of and tolerance to these techniques was evaluated. For all three patients, plasma leucine levels decreased dramatically from 2186, 3818 and 2536 mumol/L to 1131, 1275 and 488 mumol/L, respectively. Leucine clearance obtained was 4.28 ml/min in haemodiafiltration. Their patients' neurological status improved rapidly and they have a normal developmental quotient at 22 months, 13 months, and 11 months of age, respectively. Tolerance was good except for hypothermia and drop in haematocrit in all cases. Haemodiafiltration management was more cumbersome and time consuming because it required continual adjustment of the substitution fluid flow rate to precisely balance inflow and outflow rates. We recommend continuous venovenous haemodialysis as the therapy of choice. It might be anticipated that improvement of this technique, by increasing dialysate flow rate and blood flow rate, will allow leucine concentration to be decreased below 1000 mumol/L within 6-8 h, whatever the initial level.

Acute Disease↗
PubMed1996

Blood density monitoring during dialysis.

Continuous monitoring of blood density (BD) was preformed in 4 stable dialysis patients in 20 sessions using a density meter based on a mechanical oscillator technique. Mean predialysis and postdialysis BDs were 1.0427 +/- 0.0031 g/cm3 and 1.0502 +/- 0.0055 g/cm3, respectively. For similar predialysis to postdialysis total body water reduction, significant difference in the mean BD increase was found between hypotensive and nonhypotensive groups (1.29 +/- 0.07%, 0.47 +/- 0.12%, respectively; p < 0.001). Eight hypotensive episodes occurred during 6 sessions. The mean value of the blood density changes slope (dBD/dr) during the 5 min preceding a hypotensive episode increased about 2.5 times more than did the mean of the predialysis to postdialysis blood density slope (27.6 +/- 2.2 g/cm3.min.10(-5), 10.5 +/- 0.4 g/cm3.min.10(-5), respectively; p < 0.001) under the condition of a constant ultrafiltration rate of 18.9 +/- 0.6 ml/min. Continuous monitoring of blood density allows abrupt change in plasma volume to be identified and seems to have a potential utility to the prevention of symptomatic hypotension episodes in patients receiving hemodialysis.

Adult↗
PubMed1996

Age and gender-related incidence of chronic renal failure in a French urban area: a prospective epidemiologic study.

OBJECTIVE: To determine the age- and gender-related incidence of chronic renal failure in a French urban area. METHODS: Prospective study of adult patients newly identified as having established, chronic renal failure defined by serum creatinine (Scr) > or = 200 mumol/l, with the cooperation of all nephrology and dialysis units in the Ile de France district (10,660,000 inhabitants) during a 1-year period. RESULTS: 2775 patients (1780 males, 995 females) were referred with Scr > or = 200 mumol/l between July 1991 and June 1992, an overall incidence of 260/million population. 847 had advanced renal failure (Scr > or = 500 mumol/l) and 541 patients (19.5%) were > or = 75 years of age. The age-related incidence was 92, 264, 523 and 619/million population in the age groups 20-39, 40-59, 60-74 and > or = 75 years old, respectively. The annual incidence was twice as high in males than in females up to 75 years and three times as high in patients > or = 75 years (1124 vs 356/million population). Based on the proportion of patients reaching end-stage renal failure within one year of referral, the minimal estimation of the need for supportive therapy is 81/million/year. CONCLUSIONS: This epidemiological study in a large French urban area indicates an incidence of 260 patients per million population annually referred to nephrology units for chronic renal failure defined by Scr > or = 200 mumol/l, with a marked preponderance of males and a dramatic increase of incidence with age in both genders.

Adult↗
PubMed1996

[Demography and effects of chronic renal insufficiency in Ile-de-France].

In order to assess the incidence of chronic renal failure (CRF) and the demographic characteristics of affected patients, a prospective, multicenter epidemiologic study was conducted with the cooperation of all nephrology and dialysis units in the Ile-de-France district, the total population of which is 10660000 inhabitants (source: national census, march 1990). Included were patients with a plasma creatinine (Pcr) concentration > or = 200 mumol/l referred during the one-year period from July 1, 1991 until June 30, 1992. The overall response rate was 98.5%. A total of 2775 adult patients were recorded, including 1780 males (64%) with a mean (+/- SD) age of 58.1 +/- 16.3 years and a mean Pcr of 447 +/- 214 mumol/l, and 995 females (36%) with a mean age of 59.2 +/- 16.4 years and a mean Pcr of 425 +/- 185 mumol/l. Age of patients was < 40 in 16%, 40-59 in 31%, 60-74 in 34% and > or = 75 years in 19%. Pcr was 200-399 mumol/l in 54%, 400-599 mumol/l in 25%, 600-799 mumol/l in 12% and > or = 800 mumol/l in 9%. The overall incidence of CRF was 260/million population/year, twice higher in males than in females (348 vs 179/10(6)/year, p < 0.001). Incidence of CRF dramatically rose with age in both genders, with figures as high as 1124 and 356/10(6)/year respectively in male and female patients aged > or = 75 years, vs 288 and 151/10(6)/year in patients aged < 40 years. A sequential evaluation was performed in a representative sample of 251 patients with initial Pcr > or = 300 mumol/l. End-stage renal failure (ESRF) was reached within one year in 99% of patients with PCr > 600, 49% with Pcr 500-599, 24% with PCr 400-499 and 11% with PCr 300-399 mumol/l. Based on these figures, the predicted incidence of ESRF within one year of referral was 864 out of the 2775 patients, an estimated annual incidence of 81 patients per million population. In conclusion, this prospective study affords the first direct information on the incidence of chronic renal failure and the demographic characteristics of patients with CRF in the Ile-de-France district. Due to the design of the study conducted only in nephrology units, the estimated figure of 81 new patients per million population per year reaching ESRF is a minimal evaluation. In view of the relentless aging of population in France, an incidence of at least 100 ESRF patients per million population per year is to be expected in the next future.

Adult↗
PubMed1995

Accumulation of 5 alpha-reduced androgen glucosiduronates associated with impaired removal in young male hemodialysis patients.

Hypothalamic-pituitary gonadal function is commonly altered in dialysis patients. Even though an improvement in general status and well-being has been noted after recombinant human erythropoietin supplementation, no significant changes were observed in the sex hormone profile. Pituitary gonadal axis as well as 5 alpha-reduced androgen glucosiduronates (i.e. 5 alpha-androstane,3 alpha,17 beta-diol and androsterone) profiles were studied in 23 young male stable dialyzed patients and compared to an age-matched group of healthy subjects. 5 alpha-Reduced androgen glucosiduronates are products of peripheral testosterone (T) metabolism and seem to be a useful tool in assessment of the male androgen status. Their polarity facilitates their urinary excretion, and their clearance is similar to the glomerular filtration rate in healthy men. We observed 1) a pituitary-Leydig cell dysfunction supported by normal serum estradiol and T levels, low free T, and increased LH levels; 2) an alteration of the dehydroepiandrosterone (DHEA) sulfate-DHEA interconversion, reflected by a dramatic decrease in DHEA while DHEA sulfate levels remained in the normal range; 3) an accumulation of 5 alpha-reduced androgen glucosiduronates, whose removal was impaired as shown by their very low sieving coefficients (< 0.012). Taken together, the above observations are consistent with alteration of spermatogenesis with respect to dialysis duration in which earlier elevated baseline serum LH levels indicate a primary defect in Leydig cell function.

Adolescent↗
PubMed1995

Factors influencing progression of renal failure in autosomal dominant polycystic kidney disease.

Autosomal dominant polycystic kidney disease (ADPKD) frequently leads to end-stage renal failure (ESRF) in the sixth decade of life, but considerable heterogeneity exists in the rate of progression of renal failure. The respective contribution of genetic factors and of potentially amendable factors, such as blood pressure control or protein intake limitation, on the rate of progression in ADPKD patients is still debated. To evaluate the role of factors influencing the rate of progression of renal failure in ADPKD, we retrospectively analyzed the annual rate of decline of creatinine clearance (Ccr) in 109 ADPKD patients followed from the time a Ccr value of 30 to 50 mL per min/1.73 m2 was measured until ESRD and need for hemodialysis (Study A), and in 48 undialyzed ADPKD patients followed for at least 4 yr from the time a Ccr value of 50 to 60 mL per min/1.73 m2 was measured (Study B). In Study A, the decline in Ccr (delta Ccr) (mean +/- SE) was 5.8 +/- 0.2 mL per min/1.73 m2 per year in the whole series, and was lower in females than in males (5.0 +/- 0.2 versus 6.4 +/- 0.2, P < 0.001). Accordingly, ESRF was reached at a later age in female patients (55.1 +/- 1.2 versus 50.6 +/- 1.2 yr, P < 0.01). The age at ESRF in male patients was lower when the disease was transmitted by mother than by father (46.3 +/- 1.9 versus 54.1 +/- 1.8 yr, P < 0.01), whereas no significant effect of the gender of the affected parent was apparent in female patients. By regression analysis, there was a positive but weak relationship between delta Ccr and mean arterial pressure (average value during follow-up, 107 +/- 1 mm Hg, r = 0.224, P < 0.05) but not with dietary protein intake (mean value in follow-up, 0.87 +/- 0.03 g/kg per day, r = 0.10, P = 0.33) nor with proteinuria at baseline, which was lower than 0.3 g/day in 104 cases (r = 0.10, P = 0.28). There was a negative relationship between age at ESRF and delta Ccr (r = 0.245, P < 0.05), with a later and slower progression in older subjects. In Study B, the mean decline in renal function during follow-up was 5.3 +/- 0.4 mL/min/1.73 m2 per year, a value close to that observed in Study A. By multiple regression analysis of the overall population (studies A and B combined), only MAP, age and gender were independent predictive factors of delta Ccr but all studied parameters taken together accounted for at best 20% of delta Ccr variation. We conclude that the rate of progression of renal failure in ADPKD patients is mainly determined by gene expression, with female gender and older age associated with a slower progression, whereas blood pressure control, but not protein intake, exerts a limited beneficial influence on the rate of progression in patients with advanced polycystic kidney disease who already have significant renal insufficiency.

Adult↗
PubMed1995

Progression rate to end-stage renal failure in non-diabetic kidney diseases: a multivariate analysis of determinant factors.

BACKGROUND: The respective contribution of the type of nephropathy, gender, and proteinuria, and of the potentially alterable factors blood pressure level and daily protein intake on the rate of progression in non-diabetic renal diseases is debated. METHODS: We retrospectively analysed the influence of primary renal disease, gender, urinary protein excretion, mean arterial pressure (MAP), and dietary protein intake on the rate of decline in creatinine clearance (delta Ccr) in 159 adult patients with well-defined nondiabetic kidney diseases. All patients had been followed from a baseline Crr of 40-50 ml/min/1.73 m2 until endstage renal disease and need for dialysis. RESULTS: Mean (+/- SD) delta Ccr (ml/min/1.73 m2/year) was 9.9 +/- 6.5 in 51 patients (45 males) with chronic glomerulonephritis, 6 +/- 2.5 in 50 patients (26 males) with polycystic kidney disease, 5.5 +/- 2.4 in 17 patients (16 males) with hypertensive angionephrosclerosis, and 3.9 +/- 2 in 41 patients (21 males) with chronic tubulointerstitial nephritis. delta Ccr was higher in males than in females (7.5 +/- 5.2 versus 4.8 +/- 2.5; P < 0.001). Linear regression analysis of the whole population disclosed a strong relationship between delta Ccr and proteinuria (r2 = 0.23; P < 0.001), and a weak relationship between delta Ccr and protein intake (r2 = 0.03; P = 0.02), but no relationship between delta Ccr and MAP (r2 = 0.01; P = 0.23). Stepwise multiple regression analysis identified the type of nephropathy, gender, and proteinuria as independent predictive factors of progression; however, these factors together accounted for only 36% of the variation in delta Ccr, suggesting the contribution of other yet unidentified factors. CONCLUSIONS: Primary kidney disease and urinary protein excretion (reflecting the severity of renal disease in individual cases) appear as the major determinants of the rate of progression, with faster progression in males in all types of nephropathy, whereas potentially alterable factors such as blood pressure and protein intake had only a modest influence in the range of values observed in our patients.

Adult↗
PubMed1994

[Preserved saphenous grafts in hemodialysis. 20 years' experience].

From 1972 to 1992, 790 vascular conduits were implanted as vascular access in hemodialysis patients, of whom 402 were "longs" (length above 15 cm), with 168 PTFE grafts and 234 homosaphenous preserved vein grafts matching 136 manufactured and 98 self-prepared grafts. Functional period of time as 10 years has been obtained with the two materials, and up to twelve years with one manufactured graft. Among complications were observed 12% serious infection with PTFE graft compared to 2% with homosaphenous graft; aneurysm on 9% of PTFE grafts and 11% of saphenous graft, stenosis on vein graft anastomosis in 65% of the PTFE cases and 85% of the saphenous cases. There were 12% complications specific to PTFE grafts. Finally, homosaphenous vein is a material of choice in hemodialysis vascular access, mainly with the manufactured grafts.

Arteriovenous Shunt, Surgical↗
PubMed1994

[The Carboclip, a new, atraumatic vascular access for hemodialysis].

The Carboclip is a no-needle vascular access device made of an inverted Titanium body. The horizontal bar of 6 mm inner diameter is connected with artery and vein via a vascular graft. The vertical body houses an elastic plug in which is inserted a double canula diving in the blood stream for extracorporeal blood circulation (EBC). The body is wrapped by a flange made of microporous biocarbon in which the subcutaneous fibroblast will growth, forming an antimicrobial barrier and fixing the port to the skin. We report our experience on 30 devices implanted in 30 sheep with 26 extracorporeal circulation simulating hemodialysis. The results demonstrate good tightness of the plug as well at rest as during EBC procedure, sufficient blood flow rate of about 400 ml/min, and benefits of the microporous carbon flange.

Animals↗
PubMed1993

Lipid peroxidation abnormalities in hemodialyzed patients.

In order to test the existence of a possible oxidative damage during hemodialysis, plasma conjugated dienes (CD), plasma and red blood cell (RBC) thiobarbituric acid (TBA) reactants were investigated in 25 patients receiving regular dialysis treatment (RDT). The RBC TBA reactant concentration was significantly increased in RDT patients in comparison with healthy subjects. The extracellular antioxidant systems were evaluated by the assay of plasma antioxidant activity, plasma tocopherol, urate, transferrin, haptoglobin and ceruloplasmin levels. Except urate and transferrin, none of these parameters were different between the two groups. On the other hand, in RDT patients, RBC superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities were significantly lower than in healthy subjects. There was an inverse correlation between decreased RBC GPX and RBC TBA reactant concentration. These results show in RDT patients the existence of an oxidizing stress, mainly intracellular, which could be due, in part, to a decrease in SOD and GPX activities.

Adolescent↗
PubMed1993

Late referral to maintenance dialysis: detrimental consequences.

Thirty per cent of patients who started maintenance haemodialysis at our institution between January 1989 and December 1991 had been referred at a very late stage of their renal disease. To assess the causes and consequences of such late referral we retrospectively compared clinical and laboratory features of 65 patients who had been referred less than 1 month prior to first dialysis (late referral, or LR group) and of 153 patients who had been previously followed-up by us for more than 6 months (early referral, or ER group). Age, sex ratio, and socioeconomic status were similar in the two groups. In the LR group, 38 patients had never been referred to a nephrology unit, whereas 27 had discontinued nephrological surveillance. Fluid overload, severe hypertension, and/or pulmonary oedema was present in 57% of LR versus 15% of ER patients (P < 0.001). Mean (+/- 1 SD) systolic and diastolic blood pressure was greater in the LR than the ER group (173 +/- 19/99 +/- 12 versus 147 +/- 15/84 +/- 8 mmHg, P < 0.001). Mean plasma concentration of creatinine, urea and phosphate was significantly greater, whereas bicarbonate, calcium, haematocrit and albumin were less in the LR than the ER group. Most (88%) LR patients started dialysis in emergency conditions through central vein catheterization. Total hospital stay lasted 34.5 +/- 16.3 days in LR versus 5.8 +/- 3.0 days in ER patients (P < 0.0001), resulting in an excess cost of 0.2 million French francs per LR patient.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Kinetics of technetium-labeled heparin in hemodialyzed patients.

Technetium-labeled heparin kinetics studies were undertaken in 12 hemodialyzed patients, where heparin was used over a long term (1 to 10 years) for anticoagulation of the extracorporeal circuit. The 99mTc-heparin (99mTc VECTOSCINT, Solabco Nuclear, Coutras, France) used has a 10 mCi activity and a labeling efficiency of more than 95%. Two healthy subjects served as control. After an i.v. bolus of 2 ml 99mTc-heparin, corresponding to 170 +/- 10 IU, radioactivity of kidney, liver, knee and shoulder was recorded with a gamma camera at t1-h, t3-h and t6-h during 120, 152 and 215 s, respectively. Radioactivity recorded was computerized, giving quantitative data for comparison. In hemodialyzed patients, accumulation of radioactivity (mean +/- SEM 10(6) x activity count) was significantly higher at the knee (11.3 +/- 1.1 vs. 4.9 +/- 0.4; p < 0.05; 13.4 +/- 1.1 vs. 5.7 +/- 0.7; < 0.02; and 14.7 +/- 0.8 vs. 5.3 +/- 0.6; < 0.001), and on the shoulder (17.3 +/- 1.1 vs. 10.7 +/- 1.4; p < 0.05; 19.9 +/- 1.0 vs. 10.9 +/- 1.7; < 0.01; 20.8 +/- 1.1 vs. 10.1 +/- 0.9; < 0.01) at t1-h, t3-h and t6-h, respectively, than in control subjects at the same areas. Although direct evidence is not in hand, accumulation of heparin in bone tissue due to renal excretion failure could play a role in mineral metabolism resulting in osteopenia in hemodialyzed patients.

Bone and Bones↗
PubMed1993

Detrimental effects of late referral in patients with chronic renal failure: a case-control study.

Despite broader indications and easier access to renal replacement therapy during the past decades in Western countries, an unduly high number of patients is still referred to maintenance hemodialysis (HD) at a very advanced stage of chronic renal failure (CRF). To assess whether such late referral induces detrimental effects, we retrospectively compared clinical status and laboratory features in 20 patients who had been referred to us less than one month prior to first HD (late referral, or LR group) and in 20 sex- and age-matched controls who had undergone regular follow-up for at least six months prior to HD (early referral, or ER group). Male to female ratio was 12/8 and age averaged 53.5 years in both groups. Mean (+/- 1 SD) systolic and diastolic blood pressure were higher in LR group than in controls (180 +/- 14/102 +/- 10 vs. 153 +/- 15/86 +/- 7 mm Hg, P < 0.001) and fluid overload with pulmonary edema was present in 13/20 versus 3/20 patients (P < 0.001). Plasma concentrations (mmol/liter) of creatinine (1.12 +/- 0.27 vs 0.97 +/- 0.11, P < 0.01) and phosphate (2.58 +/- 0.47 vs. 1.92 +/- 0.31, P < 0.001) were higher, whereas plasma levels of bicarbonate (14.2 +/- 3.9 vs 22.5 +/- 4.2, P < 0.001) and calcium (1.85 +/- 0.24 vs. 2.27 +/- 0.15, P < 0.001) were lower in LR than in ER group, as were hemoglobin (7.1 +/- 1.1 vs. 9.4 +/- 0.9 g/dl, P < 0.001) and serum albumin levels (35.3 +/- 4.8 vs. 39.7 +/- 3.4, P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Urea rebound and residual renal function in the calculation of Kt/V and protein catabolic rate.

Kt/V-urea and protein catabolic rate (PCR) are used for dialysis prescription and evaluation of protein intake of patients on regular dialysis treatment. The study was undertaken to determine the implication of urea rebound and residual renal function (RRF) on the calculation of Kt/V-urea and PCR for 61 patients. Kt/V-urea and PCR were calculated, implementing or not urea rebound at one hour after the end of dialysis session. Urea and creatinine rebound rate in patients without RRF was significantly higher than in patients with RRF (P < 0.05). In patients without RRF, creatinine generation rate and Kt/V-urea calculated without rebound were significantly higher than calculated with rebound (P < 0.001). On the contrary, calculation of urea generation and PCR is not affected by these parameters. It is concluded that: (1) Rebound rate magnitude of urea and creatinine is dependent on solute molecular weight, RRF and probably on dialysis duration, whereas rebound rate magnitude of phosphorus is not affected, and (2) Rebound should be taken into account in the calculation of Kt/V-urea and creatinine generation rate in patients without RRF, otherwise, they would be overestimated.

Aged↗
PubMed1993

The most suitable calculation of Kt/V-urea: Kt/V = ln(Ci/Cf).

Although various simplified calculation formulae of Kt/V-urea based on urea kinetic modeling have been reported, all the formulae include errors such as post-dialysis urea rebound and urea generation during a dialysis session. In the present study, in order to calculate the precise Kt/V-urea, a formula of Kt/V-urea, taking into account post-dialysis plasma urea rebound and urea generation during a dialysis session (Kt/V-P) was proposed, and compared to other formulae already published, in 49 dialysis patients without residual renal function (26 M and 23 F; mean age, 65 +/- 2 years; mean dialysis duration, 70 +/- 7 mos). The precise post-dialysis plasma urea concentration was significantly higher than the actually measured post-dialysis plasma urea concentration by approximately 12%, and Kt/V-P corresponded to Kt/V-urea = ln(Ci/Cf) with the best correlation in the formulae utilized in the present study, around 1 of Kt/V-urea, which is clinically the most important range. It is concluded that Kt/V-urea = ln(Ci/Cf) is the most suitable formula for the calculation of Kt/V-urea, when post-dialysis plasma urea rebound and urea generation during a dialysis session are taken into account.

Aged↗
PubMed1992

Permeability of cellulosic and non-cellulosic membranes to endotoxin subunits and cytokine production during in-vitro haemodialysis.

The possibility of endotoxin transfer across haemodialysis membranes remains a controversial issue. Additional concern has arisen because of the recent introduction in clinical practice of highly permeable, synthetic dialysis membranes and of bacteria-contaminated bicarbonate concentrate with potential short-term and long-term hazards for haemodialysis (HD) patients. Therefore, we performed experiments in an in-vitro dialysis recirculation system using three different types of HD membranes, namely standard regenerated cellulose (Cuprophan, CU), polyacrylonitrile AN-69 (PAN), and polysulphone F-60 (PS). When radiolabelled lipopolysaccharide (125I M-LPS) from E. coli, together with 10 micrograms/ml unlabelled LPS, was added to the recirculating solution in the dialysis compartment, radioactivity could be detected in the blood compartment after 15 min and increased progressively with time up to respectively 6.7% (CU), 10.3% (PAN), and 10.3% (PS) of initial activity on the dialysate side. The addition of albumin to the solution on the blood side led to a decreased permeability of radioactivity (7.3% vs 10.3%), compared to the absence of albumin (tested only for PS membrane). Furthermore, 73% of 125I M-LPS transferred across the PS membrane in the presence of albumin was TCA-precipitable. In contrast, free iodine (Na 125I) incubated in an albumin-containing solution did not precipitate with albumin after the addition of TCA (precipitation of only 0.6%). Moreover, kinetics of transmembranous transfer of Na-125I were strikingly different from that of 125I M-LPS. Analysis by the method of sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) of the blood side solution, after LPS addition in the dialysis solution and 30 min of back-filtration, revealed the presence of several silver-stainable and autoradiographic bands of low-molecular-weight range, probably LPS fragments. Finally, the presence of LPS in the dialysate compartment led to a moderate increase in interleukin 1 (IL-1) and tumour necrosis factor alpha (TNF) concentrations in plasma as well as in monocyte culture supernatants after isolation from recirculating normal human whole blood exposed to CU, PAN, or PS membrane. In conclusion, our study provides evidence for the permeation of low-molecular-weight LPS subunits across cellulosic and non-cellulosic HD membranes. The clinical significance, if any, of such a transfer has, however, still to be demonstrated.

Cellulose↗