Modified Schwartz formula and 99mTc-DTPA plasma clearance methods to calculate glomerular filtration rate in critically ill children.

BACKGROUND: Studies comparing the modified Schwartz formula with measured GFR (m-GFR) are lacking in critically ill children. METHODS: This prospective cohort study enrolled children aged 1 month to 12 years, within 24 h of admission. m-GFR measured by technetium-99m-labeled diethylenetriaminepentaacetic acid (99mTc-DTPA) and calculated by Russell's two-sample slope-intercept method. Serum creatinine was estimated by modified Jaffe method and estimated GFR (e-GFR) calculated by modified Schwartz formula. The primary outcome was to find agreement between the two methods. Bias, precision, and accuracy were calculated. Secondary outcomes were the incidence of AKI (by p-RIFLE criteria) and the difference between the two methods to diagnose AKI. RESULTS: A total of 208 pairs were analyzed. e-GFR showed good agreement with m-GFR with a mean bias of -4.37 ml/min/1.73 m2 and precision (SD of bias) of 33.07, 95% limit of agreement -69.18 to 60.45, and intraclass correlation of 74% (95%CI 66-80%, P < 0.001). e-GFR underestimated m-GFR by 19.8% (95% CI 7.9-31.7%). Accuracy of e-GFR values within 10%, 20%, and 30% of m-GFR were 68.3%, 72.6%, and 78.8%, respectively. Incidence of AKI within 24 h was 60.1% by e-GFR and 54.3% by m-GFR (kappa 0.569, P < 0.001; sensitivity of 85.8%, 95%CI (78-91.7%). CONCLUSIONS: The modified Schwartz formula shows good agreement with 99mTc-labeled DTPA double plasma sample clearance method for calculating GFR in critically ill children aged 1 month to 12 years. The underestimation of GFR should be kept in mind while applying the formula at the bedside in PICU. TRIAL REGISTRATION: Protocol accessible at Clinical Trial Registry of India (CTRI) www.ctri.nic.in . (Trial Registered Prospectively and Registration No. CTRI/2017/10/010014) ([Registered on: 06/10/2017] Trial Registered Prospectively.) (Title "Measured glomerular filtration rate using Diethylenetriaminepentaacetic acid (DTPA) renal scan versus estimated glomerular filtration rate using modified Schwartz formula in critically ill children: A prospective observational, analytical study."). A higher resolution version of the Graphical abstract is available as Supplementary information.

[Discontinuation of Chromium-51 for clinical use: What are the possible alternatives for radiopharmacies and nuclear medicine departments?] / Arrêt de production du chrome-51 (51Cr) a usage clinique : quelles alternatives possibles pour les services de radiopharmacie et de médecine nucléaire ?

OBJECTIVES: Last October, the nuclear medicine departments were informed of the closure of the chromium-51 production line for clinical use. This radionuclide has different diagnostic indications in nephrology and hematology. It was therefore essential to set up alternative exploration protocols to overcome this production stoppage. METHODS: Chromium-51 EDTA has been replaced by technetium-99m DTPA for the determination of glomerular filtration rates. Sodium chromate was substituted by sodium pertechnetate for the determination of globular volumes. A retrospective analysis of the chromium-51 data was performed followed by a prospective study, from January to December 2019 for technetium tracers. RESULTS: One hundred and forty-four patients were included in the study. Forty-two EDTA-51Cr and 30 DTPA-99mTc exams were conducted and compared. There were no significant differences between the methods used to assess renal function (P=0.355). For the determination of blood cell and plasma volumes, 47 tests with 51Cr and 125I and 25 tests with 99mTc and 125I were performed and compared. There were no significant differences in the determination of total (P=0.325) and globular (P=0.148) volumes. CONCLUSIONS: The study carried out shows that there is no significant difference between the results obtained with chromium-51 and technetium tracers. As a result, clinical activity was maintained in good conditions.

[Effects of electroacupuncture at acupoints with different nerve segments on gastric emptying in OT gene knockout mice].

OBJECTIVE: To observe the effects of electroacupuncture (EA) at acupoints with different nerve segments on gastric emptying in oxytocin (OT) gene knockout mice, and to explore the role of paraventricular nucleus OT in EA regulating gastric function. METHODS: Twenty OT knockout mice and twenty wild-type mice (8-9 weeks old, male and female in half) were divided into a control group, a Zusanli (ST 36) group, a Neiguan (PC 6) group and a Weishu (BL 21) group randomly, 5 mice in each group. The mice in the control group received no acupuncture; the mice in the Zusanli (ST 36) group, Neiguan (PC 6) group and Weishu (BL 21) group were treated with EA at unilateral "Zusanli" (ST 36), "Neiguan" (PC 6) and "Weishu" (BL 21) for 15 min respectively. Subsequently, the mice were treated with intragastric administration with milk loaded with technetium-99m diethylene triamine pentaacetic acid (99mTc-DTPA), immediately followed by scanning of single photon emission computed tomography (SPECT) to test gastric emptying for 50 min; the original data was collected and analyzed to obtain the half gastric emptying time (GET 1/2), 50-min stomach residue rate and gastric emptying curve. RESULTS: The wild-type mice group:compare with the control group, after EA at "Zusanli" (ST 36) and "Neiguan" (PC 6), the GET 1/2 and 50-min stomach residue rate were significantly reduced, which could improve the gastric emptying of wild-type mice (P<0.01, P<0.05); after EA at "Weishu" (BL 21), the GET 1/2 and 50-min stomach residue rate were significantly increased, which could inhibit the gastric emptying of wild-type mice (P<0.01, P<0.05). The OT gene knockout mice group:compared with the control group, EA at "Zusanli" (ST 36) and "Neiguan" (PC 6) had no significant effects on gastric emptying (both P>0.05); after EA at "Weishu" (BL 21), the GET 1/2 and 50-min stomach residue rate were significantly increased, which could inhibit the gastric emptying of OT gene knockout mice (both P<0.01). Gastric emptying curve:the gastric emptying of OT gene knockout mice was significantly faster than that of wild-type mice. CONCLUSIONS: The effects of EA at acupoints with different nerve segments on gastric emptying in mice are different, and the knockout of OT gene could accelerate the gastric emptying, and influence the acupuncture effect of several acupoints. It is suggested the paraventricular nucleus OT neurons, as the initiating device of autonomic nervous pathways, might participate in EA regulating the gastric function to inhibit the gastric emptying, with the form of neural and neuroendocrine.

Laser stimulation of the acupoint 'Zusanli' (ST.36) on the radiopharmaceutical biodistribution in Wistar rats.

Laser used to stimulate acupoints is called laser acupuncture (LA). It is generally believed that similar clinical responses to manual acupuncture can be achieved. Here we analysed the effects of the laser (904 nm) at the 'Zusanli' acupoint (ST.36) of the stomach meridian on the biodistribution of the radiopharmaceutical Na(99m)TcO4. Wistar rats were divided into control (CG) and experimental groups (EG). The EG were exposed daily to the laser (904 nm) at ST.36 with 1 joule/min (40 mW/cm(2)) for 1 min. The animals of the CG were not exposed to laser at all. On the 8th day after LA, the animals were sedated and Na(99m)TcO4 was administered. After 10 min, the animals were all sacrificed and the organs removed. The radioactivity was counted in each organ to calculate the percentage of radioactivity of the injected dose per gram (%ATI/ g). Comparison of the %ATI/g in EG and CG was performed by Mann-Whitney test. The %ATI/g was significantly increased in the thyroid due to the stimulation of the ST.36 by laser. It is possible to conclude that the stimulation of ST.36 does lead to biological phenomena that interfere with the metabolism of the thyroid.

Effect of branched-chain amino acid supplementation on functional liver regeneration in patients undergoing portal vein embolization and sequential hepatectomy: a randomized controlled trial.

BACKGROUND: Portal vein embolization (PVE) can decrease the resection ratio for major hepatectomy. (99m)Tc-galactosyl human serum albumin (GSA) scintigraphy is useful for evaluating quantitative functional liver volume. Branched chain amino acids (BCAAs) modulate liver function and regeneration. We analyzed the effects of BCAAs, in terms of liver function and regeneration after PVE, in combination with major hepatectomy. METHODS: This randomized controlled trial was conducted for patients receiving PVE through to complete hepatectomy from September, 2011 to June, 2013. BCAA granules were added two times a day to a conventional diet in the BCAA administration group (BCAA group). The primary end point was functional liver regeneration of the future remnant liver after PVE followed by hepatic resection. Functional liver regeneration was assessed by the liver uptake value obtained from (99m)Tc-GSA scintigraphy single-photon-emission computed tomography/computed tomography fusion images. The secondary end points were volumetric liver regeneration and changes in liver function and laboratory data. RESULTS: A BCAA group (n = 13) and a non-BCAA group (control group; n = 15) were included. The primary end point was partially met: the liver uptake value significantly increased in the BCAA group compared with the control group 6 months after hepatic resection (266.7% vs 77.6%, P = 0.04) and marginally increased after PVE (43.8% vs 17.4%, P = 0.079). Following PVE, the increment of the uptake ratio of the liver to the liver plus heart at 15 min was significantly less in the BCAA group than in the control group (0.0 and 0.01, P = 0.023). CONCLUSIONS: BCAA supplementation improved functional liver regeneration and function in patients undergoing PVE followed by major hepatic resection.

A receptor-targeted fluorescent radiopharmaceutical for multireporter sentinel lymph node imaging.

PURPOSE: To determine the imaging and receptor-binding properties of a multireporter probe designed for sentinel lymph node (SLN) mapping via nuclear and fluorescence detection. MATERIALS AND METHODS: The animal experiments were approved by the institutional animal care and use committee. A multireporter probe was synthesized by covalently attaching cyanine 7 (Cy7), a near-infrared cyanine dye, to tilmanocept, a radiopharmaceutical that binds to a receptor specific to recticuloendothelial cells. In vitro binding assays of technetium 99m (99mTc)-labeled Cy7 tilmanocept were conducted at 4°C by using receptor-bearing macrophages. Optical SLN imaging after foot pad administration was performed by using two molar doses of Cy7 tilmanocept. Six mice were injected with 0.11 nmol of 99mTc-labeled Cy7 tilmanocept (low-dose group); an additional six mice were injected with 31 nmol of 99mTc-labeled Cy7 tilmanocept (high-dose group) to saturate the receptor sites within the SLN. After 2.5 hours of imaging, the mice were euthanized, and the sentinel and distal lymph nodes were excised and assayed for radioactivity for calculation of SLN percentage of injected dose and extraction. Four mice were used as controls for autofluorescence. Standard optical imaging software was used to plot integrated fluorescence intensity against time for calculation of the SLN uptake rate constant and scaled peak intensity. Significance was calculated by using the Student t test. RESULTS: In vitro binding assays showed subnanomolar affinity (mean dissociation constant, 0.25 nmol/L±0.10 [standard deviation]). Fluorescence imaging showed a detection sensitivity of 1.6×10(3) counts·sec(-1)·µW(-1) per picomole of Cy7. All four imaging metrics (percentage of injected dose, SLN extraction, SLN uptake rate constant, and expected peak fluorescence intensity) exhibited higher values (P=.005 to P=.042) in the low-dose group than in the high-dose group; this finding was consistent with receptor-mediated image formation. CONCLUSION: The multireporter probe 99mTc-labeled Cy7 tilmanocept exhibits in vitro and in vivo receptor-binding properties for successful receptor-targeted SLN mapping with nuclear and optical imaging.

Design and gamma scintigraphic evaluation of colon specific pectin-EC pellets of secnidazole prepared by powder layering technology.

The aim of the present study was to prepare a colon targeted pellet formulation of secnidazole and to evaluate the formulation in vitro and in vivo by a gamma scintigraphy method. Pectin/ethyl cellulose in different ratios and in different coating labels with plasticizer was used to prepare secnidazole pellets by a powder layering technique. The formulations were tagged with 99mTC-DTPA, a tracer in gamma scintigraphy to evaluate its transit behavior in rabbits. Morphology and compatibility were studied using Scanning Electron Microscopy, IR spectroscopy and Differential Scanning Calorimetry were used for the characterization of prepared pellets. The in-vitro study suggested that pectin (59%) esterification and ethyl cellulose 45cps at 20% coating label led to an optimum bacterial enzyme dependent released behavior. The optimized formulation was subjected to an in-vivo transit study. Scintigraphy images clearly indicated that the formulation can delay the drug release prior to the colon. The average time of gastric emptying and colon arrival was 57 min and 6.08 h, respectively. The coated pellets prepared by powder layering technology successfully released drug in the colon indicating that site specificity has been achieved with pectin 59% esterification and ethyl cellulose 45 cps at 1:2 ratio with 20% coating label.

A randomized crossover study of the effects of glutamine and lipid on the gastric emptying time of a preoperative carbohydrate drink.

BACKGROUND & AIMS: Supplementing preoperative carbohydrate drinks with glutamine may lead to benefits in addition to reducing insulin resistance, but amino acids may delay gastric emptying (GE). The effects of supplementing a preoperative carbohydrate drink (CCD) with glutamine or lipid on GE were studied. METHODS: Ten healthy male volunteers ingested 410 ml of one of three isocaloric-isovolumetric carbohydrate-based drinks labelled with (99m)Tc-DTPA: CCD (preOp(®), Nutricia, UK, 50 g carbohydrate), CCD/G (preOp(®), 36 g carbohydrate + 15 g glutamine) or CCD/L (preOp(®), 36 g carbohydrate + 7 g lipid) in this randomized, blinded, three-way crossover study. After baseline measurements, GE was measured scintigraphically and blood sampled for insulin, glucose and glucagon-like peptide 1 (GLP-1) at 20 min intervals for 240 min. RESULTS: Mean (95% CI) T(90) GE times for CCD, CCD/G and CCD/L were 101 (87-115), 95 (84-107) and 87 (72-102) min, respectively. At 40 min postprandially, mean (SEM) concentrations of glucose (mmol/l) and insulin (mIU/l) were 7.5 (0.5) and 35 (5) for CCD; 6.2 (0.2) and 28 (4) for CCD/G; and 7 (0.3) and 31 (5) for CCD/L, respectively. There were no differences in postprandial GLP-1 concentrations. CONCLUSIONS: Glutamine and lipid supplementation did not prolong the GE of CCD but did 'blunt' postprandial glucose and insulin responses, independent of GLP-1 concentrations. Registered under ClinicalTrials.gov Identifier no. NCT00943020.

Histopathological and scintigraphic comparisons of the protective effects of L-carnitine and amifostine against radiation-induced late renal toxicity in rats.

1. The aim of the present study was to compare the protective effects of L-carnitine and amifostine against radiation-induced late nephrotoxicity using technetium-99m diethylenetriaminepentaacetic acid scintigraphy and histopathological examination. 2. Seventy-one Albino rats were randomly divided into six groups as follows: (i) AMI + RAD (n = 15), 200 mg/kg, i.p., amifostine 30 min prior to irradiation (a single dose of 9 Gy); (ii) LC + RAD (n = 15), 300 mg/kg, i.p., L-carnitine 30 min prior to irradiation; (iii) LC (n = 10), 300 mg/kg, i.p., L-carnitine 30 min prior to sham irradiation; (iv) AMI (n = 10), 200 mg/kg, i.p., amifostine 30 min prior to sham irradiation; RAD (n = 11), 1 mL/kg, i.p., normal saline 30 min prior to irradiation; and (vi) control (n = 10), 1 mL/kg, i.p., normal saline 30 min prior to sham irradiation. Scintigraphy was performed before treatment and again 6 months after treatment. Kidneys were examined by light microscopy and a histopathological scoring system was used to assess the degree of renal damage. 3. The main histopathological findings were proximal tubular damage and interstitial fibrosis. Glomerular injury was similar in all groups. Tubular degeneration and atrophy were less common in the AMI + RAD group than in the RAD group (P = 0.011 and P = 0.015, respectively), as well as in the LC + RAD group compared with the RAD group (P = 0.028 and P = 0.036, respectively). Interstitial fibrosis in the AMI + RAD and LC + RAD groups was significantly less than that in the RAD group (P = 0.015 and P = 0.015, respectively). The highest total renal injury score (9) was seen in the RAD group. On scintigraphy, there were significant differences in post-treatment time to peak count (T(max)) and time from peak count to half count (T((1/2))) values (P = 0.01 and 0.02, respectively) between groups in the right kidney. In the control and RAD groups, the T((1/2)) of the right kidney was 8 +/- 2 and 21 +/- 2 min, respectively. The T(max) values for the AMI + RAD and LC + RAD groups (2.8 +/- 0.2 and 3.2 +/- 0.2 min, respectively) were similar to those in the control group (2.5 +/- 0.3 min). 4. Based on the results of the present study, L-carnitine and amifostine have comparable and significant protective effects against radiation-induced late nephrotoxicity.

The preliminary experimental and clinical study of the relationship between the pigment gallstone and intestinal mucosal barrier.

AIMS: To investigate the relations between the formation of pigment gallstone and the function of the intestinal mucosal barrier, as well as the underlying mechanism. METHODS: Eighty guinea pigs were randomly divided into three groups in which they were respectively given normal diet, gallstone-causing diet, and gallstone-formation diet with a supplementary intestinal mucosal protection compound known as glutamine. The model of pigment gallstone was established after 8 weeks of dietary administration. Indices about the function of the intestinal mucosal barrier and bacterial translocation were measured. Clinical cases were divided into three groups: control, cholesterol gallstone, and pigment gallstone, where the levels of plasma diamine oxidase (DAO), plasma endotoxin and the excretion rates of technetium 99m-diethylene triamine pentaacetic acid (99mTC-DTPA) in the urine of each group were measured. RESULTS: In the pigment gallstone group, the level of plasma DAO and endotoxin, the excretory ratio of lactulose and mannitol in urine, the bacterial translocation ratio in the celiac lymph nodes and the activities of beta-glucuronidase increased comparing to the control group. The gallstone-formation rate for the intestinal mucosal protection group (GLN) decreased, and other indices, except the activity of beta-glucuronidase, were all lower than that of gallstone-formation group. In the clinical experiment, the levels of plasma DAO and endotoxin, as well as the excretory rate of 99mTC-DTPA in urine were higher in the patients with gallstones than that in the control group. CONCLUSIONS: The formation of pigment gallstone was related to the abnormal function of the intestinal mucosal barrier. The abnormality in the function of the intestinal mucosal barrier probably induced the formation of gallstone by a bacterial translocation mechanism.

Scintigraphic evaluation of colon targeting pectin-HPMC tablets in healthy volunteers.

The in vivo evaluation of colon-targeting tablets was conducted in six healthy male volunteers. A pectin-hydroxypropyl methylcellulose coating was compressed onto core tablets labelled with 4MBq (99m)Tc-DTPA. The tablets released in the colon in all subjects; three in the ascending colon (AC) and three in the transverse colon (TC). Tablets that released in the TC had reached the AC before or just after food (Group A). The other three tablets released immediately upon AC entry at least 1.5h post-meal (Group B). Release onset for Group B was earlier than Group A (343min vs 448min). Group B tablets exhibited a clear residence period at the ileocaecal junction (ICJ) which was not observed in Group A. Prolonged residence at the ICJ is assumed to have increased hydration of the hydrogel layer surrounding the core tablet. Forces applied as the tablets progressed through the ICJ may have disrupted the hydrogel layer sufficiently to initiate radiolabel release. Conversely, Group A tablets moved rapidly through the AC to the TC, possibly minimising contact times with water pockets. Inadequate prior hydration of the hydrogel layer preventing access of pectinolytic enzymes and reduced fluid availability in the TC may have retarded tablet disintegration and radiolabel diffusion.

Outpatient tinzaparin therapy in pulmonary embolism quantified with ventilation/perfusion scintigraphy.

BACKGROUND: Out-of-hospital treatment of patients with deep-vein thrombosis (DVT) is routine in many countries regardless of frequent concomitant asymptomatic pulmonary embolism (PE) in this group. However, patients with symptoms and verified PE are still regularly treated in hospital. The objectives were to test a model for outpatient tinzaparin therapy and to evaluate its safety and efficacy in patients with symptomatic, small or medium-sized PE using quantitative ventilation/perfusion scintigraphy (qV/P SCINT) for patient selection and follow up. MATERIAL/METHODS: This prospective study included 102 patients treated with tinzaparin and warfarin for 5 days at a patient hotel. PE was quantified scintigraphically as loss of perfusion with preserved ventilation at segmental or subsegmental levels (mismatch). Points were attributed to segments of reduced ventilation (RoVent) and perfusion (RoPer). A holistic principle of interpretation was applied. Patients were excluded if they had >14 RoPer points (7 segments) or >7 RoVent points. Clinical follow-up and scintigraphy were repeated at discharge in 100 patients and after 13 months on average. RESULTS: Embolism diminished by 44% after 5 days and demanding symptoms declined. There was no thromboembolic mortality in the trial. At late follow-up, PE had not recurred in patients with resolution after 5 days. In those with insufficient early response, persistent perfusion defects were usually observed. CONCLUSIONS: The results indicate the safety and efficacy of outpatient treatment of PE according to our model and merit larger, multicenter, controlled studies.

Síndrome de hipotensión intracraneal espontánea: utilidad de la cisternogammagrafía isotópica con 99mTc-DTPA / Spontaneous intracranial hypotension: the value of isotope cisternoscintigraphy using 99mTc-DTPA

Introducción. La hipotensión intracraneal espontánea (HIE) es una entidad poco frecuente que predomina en adultos jóvenes y se caracteriza por la presencia de una cefalea aguda o subaguda que aparece con la bipedestación y mejora con el decúbito. Caso clínico. Mujer de 35 años, que refiere desde hace tres meses cefaleas holocraneales, con mareos e inestabilidad de la marcha, que aumentan en bipedestación y ceden parcialmente en decúbito, asociadas a acúfenos bilaterales. Refiere un antecedente de pequeño esfuerzo hace cuatro meses, con brusca cervicalgia posterior no irradiada, que cedió espontáneamente. Teniendo en cuenta los hallazgos clínicos y radiológicos tras la realización de una resonancia magnética cerebral y cervical, se solicita a nuestro servicio la realización de una cisternogammagrafía. Conclusión. La cisternogammagrafía isotópica con 99mTc-DTPA confirmó el diagnóstico del proceso y permitió localizar la fuga de líquido cefalorraquídeo, por lo que creemos oportuno destacar su utilidad en el diagnóstico del síndrome de HIE, con la finalidad de obviar la realización de otras exploraciones complementarias invasivas que conllevan cierta morbimortalidad (AU)

Introduction. Spontaneous intracranial hypotension (SIH) is an infrequent clinical entity that is found predominantly in young adults and is characterised by the presence of acute or subacute headaches that appear on standing up and subsides on lying down. Case report. A 35-year-old female with a three-month history of holocranial headaches, accompanied by dizziness and gait instability, which increase on standing up and diminish to a certain extent on lying down, associated to bilateral tinnitus. The patient’s history included a slight strain made 4 months earlier, with a sudden non-irradiated pain in the back of the neck that got better spontaneously. On the basis of the clinical and radiological findings from an MRI scan of the head and neck, our service was asked to perform a cisternoscintigraphy. Conclusions. Isotope cisternoscintigraphy using 99mTc-DTPA confirmed the diagnosis of the process and enabled us to locate the CSF leak. We therefore think it advisable to highlight its value in the diagnosis of SIH syndrome so as to be able to avoid the use of other invasive complementary explorations that entail a certain degree of morbidity and mortality (AU)

Preclinical studies of [(99m)Tc]DTPA-mannosyl-dextran .

We report the preclinical testing of a synthetic receptor-binding macromolecule, [(99m)Tc]DTPA-mannosyl-dextran (36 kDa, 8 DTPA and 55 mannosyl units per dextran, K(D) = 0.12 nM), for sentinel node detection. Nonclinical safety studies included cardiac pharmacology safety studies, acute toxicology and pathology studies at 50 and 500 times the scaled human dose in both rats and rabbits after foot pad administration, and perivascular irritation studies in rabbits following intra-muscular administration at 100 and 1000 times the scaled human dose. Biodistribution studies in rabbits at 15 m, 1 h, and 3 h indicated that [(99m)Tc]DTPA-mannosyl-dextran cleared the hind foot pad with a biological half-life of 2.21 +/- 0.27 h. Other than mild hepatocyte hypertrophy in rabbits, no abnormalities in toxicology or pathology were found. Intravenous administration had no effect on survival, any clinical observations, electrocardiograms, or blood pressures. Intramuscular injection had no effect on survival, clinical observations, injection site observations, or injection site histopathology. The estimated absorbed radiation dose to the affected breast was 0.15 mGy/MBq and the effective dose was 1.06 x 10(-2) mSv/MBq. This preclinical study demonstrates that [(99m)Tc]DTPA-mannosyl-dextran has no toxicities and has an acceptable biodistribution and radiation dose.

Investigation of pulmonary epithelial permeability in patients after hyperbaric oxygen therapy by 99mTc diethylenetriaminepentaacetic acid aerosol inhalation lung scintigraphy.

The aim of this study was to evaluate the possibility of pulmonary epithelial permeability damage in patients after hyperbaric oxygen therapy (HBOT) by 99mTc diethylenetriaminepentaacetic acid (99mTc-DTPA) aerosol inhalation lung scintigraphy. Twenty-five controls and 21 patients with normal chest X-rays and no cigarette smoking for at least 1 year were recruited for the study. 99mTc-DTPA aerosol inhalation lung scans were performed after 20 HBOT sessions in 21 patients with refractory osteomyelitis or diabetic foot. The HBOT with 100% oxygen at 2.5 atm absolute for 100 min was performed five times a week. Clearance rates (%/min) of 99mTc-DTPA aerosol in each lung field were calculated from the dynamic images for 30 min. Clearance rates of 99mTc-DTPA aerosol were compared between patients and controls by the unpaired t test. Thirteen patients who had 99mTc-DTPA aerosol lung scans before and after HBOT therapy studies were tested for statistical significance by using the paired t test. There was no statistically significant difference (P>0.05, unpaired t test) between patients and controls in every lung field. For the 13 patients who had 99mTc-DTPA aerosol studies both before and after 20 HBOT sessions, the results also showed no statistically significant difference (P>0.05, paired t test). It is concluded that there was no demonstrable pulmonary epithelial permeability change under current clinical HBOT protocol.

A double-blind trial of perindopril and nitrendipine in incipient diabetic nephropathy.

UNLABELLED: We conducted a randomised, double-blind multicentre trial to compare the efficacy of the inhibitor of the angiotensin-converting enzyme (ACE) perindopril (P) with nitrendipine (N) in incipient diabetic nephropathy. METHODS: Forty-six patients with insulin-treated diabetes mellitus and mild-to-moderate hypertension and stable microalbuminuria were examined. P 4 or 8 mg once daily was compared to N 20 or 40 mg once daily; an optional open combination treatment with indapamide 2.5 mg once daily was given when needed. Main outcome measures were urinary albumin excretion rate, creatinine clearance and isotopic clearance measurements after 12 months. RESULTS: Baseline characteristics (blood pressure, HbA1, renal function) were highly comparable between groups. No serious adverse events occurred during the study period. Blood pressure was controlled (<140/90 mmHg) in all patients except for one in each group who dropped out. At the end of the study, albumin excretion rate was stabilized in both groups (P: 72% of baseline, N: 108%, NS). There were no significant differences found in radiometric clearance measurements. Creatinine clearance rose in patients treated with P by 10.0 ml/min on average, while it decreased by 9.8 m/min under N treatment (group effect: p<0.05). CONCLUSIONS: In this head-to-head comparison, P and N were effective in stabilising most parameters of renal function in incipient diabetic nephropathy.

[Assessment of functional severity on in vivo hepatic 31P-MRS in diffuse hepatic disease: comparative studies with 99mTc-GSA].

The purpose of this study was to compare the assessment of functional severity on in-vivo hepatic 31P-MRS in diffuse hepatic disease with functional severity assessed with 99mTc galactosyl serum albumin (99mTc-GSA). 31P-MRS was performed in 10 healthy control subjects and 16 patients with diffuse hepatic disease. Data were expressed as peak area ratios: PME/beta-ATP, PDE/beta-ATP, PME/PDE, Pi/beta-ATP, and PME/Pi. The functional severity of hepatic damage was evaluated visually and quantitatively (HH15, LHL15) by 99mTc-GSA in the group of patients with diffuse hepatic disease. Visual evaluation was classified into four grades based on anterior images of cardiac blood-pool and liver. We studied the correlation of spectral metabolic ratios and functional severity by 99mTc-GSA. We found statistically significant differences (ANOVA) among the classifications of Grade I, Grade II, and Grade III with both PME/beta-ATP and PME/PDE. A statistically significant direct correlation was found between HH15 and both PME/beta-ATP and PME/PDE. A significant inverse correlation was also seen between LHL15 and both PME/beta-ATP and PME/PDE. The studies comparing 31P-MRS with functional severity assessed by 99mTc-GSA showed that PME/beta-ATP and PME/PDE were useful for the assessment of functional severity in patients with diffuse hepatic disease.

Effects of hydrogen peroxide on the guinea-pig tracheobronchial mucosa in vivo.

Lumenal entry of plasma (mucosal exudation) is a key feature of airway inflammation. In airways challenged with histamine-type mediators and allergen the mucosal exudation response occurs without causing epithelial derangement and without increased airway absorption. In contrast, reactive oxygen metabolites may cause mucosal damage. In this study, involving guinea-pig airways, we have examined effects of H2O2 on airway exudation and absorption in vivo. Vehicle or H2O2 (0.1 and 0.5 M) was superfused onto the tracheobronchial mucosal surface through an oro-tracheal catheter. 125I-albumin, given intravenously, was determined in tracheobronchial tissue and in lavage fluids 10 min after challenge as an index of mucosal exudation of plasma. The tracheobronchial mucosa was also examined by scanning electron microscopy. In separate animals, 99mTc-DTPA was superfused 20 min after vehicle or H2O2 (0.1 and 0.5 M) had been given. A gamma camera determined the disappearance rate of 99mTc-DTPA from the airways as an index of airway absorption. The high dose of H2O2 (0.5 M) produced epithelial damage, increased the absorption of 99mTc-DTPA (P < 0.001), and increased the exudation of plasma (P < 0.001). Notably, it appeared that all extravasated plasma had entered the airway lumen within 10 min. These data demonstrate that H2O2 differs from exudative autacoids such as histamine by causing both epithelial damage and plasma exudation responses. These data also agree with the view that the epithelial lining determines the rate of absorption and is responsible for the valve-like function that allows lumenal entry of extravasated bulk plasma without any increased inward perviousness.

Glycyl-glutamine-enriched long-term total parenteral nutrition attenuates bacterial translocation following small bowel transplantation in the pig.

BACKGROUND: Improvements in immunosuppression, operative procedure, and posttransplant management have made clinical small bowel transplantation (SBT) feasible. Ischemia and reperfusion injury, total parenteral nutrition (TPN), and devoidment of enteral feeding lead to graft atrophy, gut barrier dysfunction, and bacterial translocation. Glutamine (Gln) is the principal fuel for the enterocyte. The influence of Gln dipeptide-supplemented TPN, especially long-term TPN, on intestinal graft permeability and bacterial translocation is not clear following SBT in the large animal model. Therefore, we studied the effect of glutamine dipeptide, glycyl-glutamine (Gly-Gln), on bacterial translocation following SBT in the pig, which has a physiology similar to humans. MATERIALS AND METHODS: The outbred pigs underwent segmental small bowel autotransplantation and were divided into two groups. In the STPN group (n = 5), the animal received standard TPN devoid of Gly-Gln for 28 days. In the GTPN group (n = 5), the animal received isonitrogenous (0.3 g/kg.day) and isocaloric (33 kcal/kg.day) TPN solution with 2% Gly-Gln for 28 days. RESULTS: At the end of the experiment, Gly-Gln-enriched TPN could maintain the plasma Gln level, graft mucosal Gln and protein concentrations, and skeletal muscle Gln and protein concentrations. Gly-Gln-enriched TPN significantly decreased the bacterial number of mesenteric lymph nodes in the liver and spleen and intestinal permeability to 99mTc-DTPA. There were no significant differences in body weight gain. CONCLUSIONS: The Gly-Gln-enriched long-term TPN may maintain the plasma Gln level, mucosal and muscle Gln, and protein concentrations and attenuate the intestinal permeability to 99mTc-DTPA and bacterial translocation following small bowel transplantation in the pig.

Prospective study of simultaneous orthoiodohippurate and diethylenetriaminepentaacetic acid captopril renography. The Einstein/Cornell Collaborative Hypertension Group.

UNLABELLED: Captopril renography (CR) has been established in the past 10 yr as a useful diagnostic test for renovascular hypertension. However, direct comparison of tubular and glomerular tracers, quantitative criteria, comparison of quantitative and qualitative results and the reliability of the results in renal failure have not been described in a systematic, prospective fashion. METHODS: Same-day baseline and CR using 99mTc-labeled diethylenetriaminepentaacetic acid (DTPA) and [131I]orthoiodohippurate (OIH) were simultaneously performed in two groups of hypertensive subjects, one with demographically defined essential hypertension (n = 43) and the other (n = 60) with a high prevalence of renovascular disease, defined with angiograms. Quantitative criteria for abnormal CR were derived from results among the subjects with essential hypertension. Qualitative analysis was performed using widely established criteria. RESULTS: There were no statistically significant differences between quantitative and qualitative accuracy, between OIH and DTPA or among quantitative parameters. The best accuracies for quantitative CR were 56% with DTPA (n = 57) and 60% with OIH (n = 60), in both cases using the relative renal uptake parameter. Qualitative CR (n = 60) had accuracies of 43% (DTPA) and 50% (OIH), both hindered by 29 (DTPA) and 25 (OIH) abnormal but nondiagnostic studies. Two false-positive studies were detected. Twenty-seven of 29 nondiagnostic studies were associated with a glomerular filtration rate of <50 ml/min (n = 17), one small kidney (n = 17) and/or bilateral renal artery stenosis (n = 16). Supplemental measurement of in vitro stimulated plasma renin activity insignificantly (p > 0.10) and improved accuracies to 63% (DTPA) and 70% (OIH), without introducing additional false-positive tests. CONCLUSION: Orthoiodohippurate and DTPA have comparable accuracy in prospective simultaneous evaluation of CR. False-positive studies are fewer than 5%. The accuracies of quantitative and qualitative criteria do not differ significantly but may be improved by supplemental use of the in vitro stimulated plasma renin activity. In individuals with renal insufficiency, small kidneys and/or bilateral renal artery disease, up to 48% of CR studies are abnormal but nondiagnostic.