Thoracic impedance pneumography in propofol-sedated patients undergoing percutaneous endoscopic gastrostomy (PEG) placement in gastrointestinal endoscopy: A prospective, randomized trial

STUDY OBJECTIVE

To assess the efficacy of an ECG-based method called thoracic impedance pneumography to reduce hypoxic events in endoscopy.

DESIGN

This was a single center, 1:1 randomized controlled trial.

SETTING

The trial was conducted during the placement of percutaneous endoscopic gastrostomy (PEG).

PATIENTS

173 patients who underwent PEG placement were enrolled in the present trial. Indication was oncological in most patients (89%). 58% of patients were ASA class II and 42% of patients ASA class III.

INTERVENTIONS

Patients were randomized in the standard monitoring group (SM) with pulse oximetry and automatic blood pressure measurement or in the intervention group with additional thoracic impedance pneumography (TIM). Sedation was performed with propofol by gastroenterologists or trained nurses.

MEASUREMENTS

Hypoxic episodes defined as SpO2 < 90% for >15 s were the primary endpoint. Secondary endpoints were minimal SpO2, apnea >10s/>30s and incurred costs.

MAIN RESULTS

Additional use of thoracic impedance pneumography reduced hypoxic episodes (TIM: 31% vs SM: 49%; p = 0.016; OR 0.47; NNT 5.6) and elevated minimal SpO2 per procedure (TIM: 90.0% ± 8.9; SM: 84.0% ± 17.6; p = 0.007) significantly. Apnea events >10s and > 30s were significantly more often detected in TIM (43%; 7%) compared to SM (1%; 0%; p < 0.001; p = 0.014) resulting in a time advantage of 17 s before the occurrence of hypoxic events. As a result, adjustments of oxygen flow were significantly more often necessary in SM than in TIM (p = 0.034) and assisted ventilation was less often needed in TIM (2%) compared with SM (9%; p = 0.053). Calculated costs for the additional use of thoracic impedance pneumography were 0.13$ (0.12 €/0.11 £) per procedure.

CONCLUSIONS

Additional thoracic impedance pneumography reduced the quantity and extent of hypoxic events with less need of assisted ventilation. Supplemental costs per procedure were negligible.

KEY WORDS

thoracic impedance pneumography, capnography, sedation, monitoring, gastrointestinal endoscopy, percutaneous endoscopic gastrostomy.

Hosing of a Long Relativistic Particle Bunch in Plasma

Experimental results show that hosing of a long particle bunch in plasma can be induced by wakefields driven by a short, misaligned preceding bunch. Hosing develops in the plane of misalignment, self-modulation in the perpendicular plane, at frequencies close to the plasma electron frequency, and are reproducible. Development of hosing depends on misalignment direction, its growth on misalignment extent and on proton bunch charge. Results have the main characteristics of a theoretical model, are relevant to other plasma-based accelerators and represent the first characterization of hosing.

Epiphytic and endophytic microbiome of the seagrass Zostera marina: Do they contribute to pathogen reduction in seawater?

Seagrass meadows provide crucial ecosystem services for coastal environments and were shown to reduce the abundance of waterborne pathogens linked to infections in humans and marine organisms in their vicinity. Among potential drivers, seagrass phenolics released into seawater have been linked to pathogen suppression, but the potential involvement of the seagrass microbiome has not been investigated. We hypothesized that the microbiome of the eelgrass Zostera marina, especially the leaf epiphytes that are at direct interface between the seagrass host and the surrounding seawater, inhibit waterborne pathogens thereby contributing to their removal. Using a culture-dependent approach, we isolated 88 bacteria and fungi associated with the surfaces and inner tissues of the eelgrass leaves (healthy and decaying) and the roots. We assessed the antibiotic activity of microbial extracts against a large panel of common aquatic, human (fecal) and plant pathogens, and mined the metabolome of the most active extracts. The healthy leaf epibiotic bacteria, particularly Streptomyces sp. strain 131, displayed broad-spectrum antibiotic activity superior to some control drugs. Gram-negative bacteria abundant on healthy leaf surfaces, and few endosphere-associated bacteria and fungi also displayed remarkable activities. UPLC-MS/MS-based untargeted metabolomics analyses showed rich specialized metabolite repertoires with low annotation rates, indicating the presence of many undescribed antimicrobials in the extracts. This study contributes to our understanding on microbial and chemical ecology of seagrasses, implying potential involvement of the seagrass microbiome in suppression of pathogens in seawater. Such effect is beneficial for the health of ocean and human, especially in the context of climate change that is expected to exacerbate all infectious diseases. It may also assist future seagrass conservation and management strategies.

Controlled Growth of the Self-Modulation of a Relativistic Proton Bunch in Plasma

A long, narrow, relativistic charged particle bunch propagating in plasma is subject to the self-modulation (SM) instability. We show that SM of a proton bunch can be seeded by the wakefields driven by a preceding electron bunch. SM timing reproducibility and control are at the level of a small fraction of the modulation period. With this seeding method, we independently control the amplitude of the seed wakefields with the charge of the electron bunch and the growth rate of SM with the charge of the proton bunch. Seeding leads to larger growth of the wakefields than in the instability case.

The efficacy and safety of direct acting antiviral treatment and clinical significance of drug-drug interactions in elderly patients with chronic hepatitis C virus infection

BACKGROUND

Direct antiviral therapies for chronic hepatitis C virus (HCV) infection have expanded treatment options for neglected patient populations, including elderly patients who are ineligible/intolerant to receive interferon (IFN)-based therapy.

AIM

To investigate the efficacy, tolerability and potential for drug-drug interactions (DDIs) of IFN-free treatment in patients aged ≥65 years in a large real-world cohort.

METHODS

A total of 541 patients were treated with different combinations of direct antiviral agents (DAAs: ledipasvir/sofosbuvir ±ribavirin; daclatasvir/sofosbuvir ±ribavirin; paritaprevir/ombitasvir ±dasabuvir ±ribavirin or simeprevir/sofosbuvir ±ribavirin in genotype 1/4, and daclatasvir/sofosbuvir ±ribavirin or sofosbuvir/ribavirin in genotype 2/3). Efficacy, safety and potential DDIs were analysed and compared between patients aged <65 years (n = 404) and patients aged ≥65 years (n = 137) of whom 41 patients were ≥75 years.

RESULTS

Sustained virological response rates were 98% and 91% in patients aged ≥65 years and <65 years, respectively. Elderly patients took significantly more concomitant medications (79% vs. 51%; P < 0.0001). The number of concomitant drugs per patient was highest in patients ≥65 years with cirrhosis (median, three per patient; range, 0-10). Based on the hep-druginteractions database, the proportion of predicted clinically significant DDIs was significantly higher in elderly patients (54% vs. 28%; P < 0.0001). The number of patients who experienced treatment-associated adverse events was similar between the two age groups (63% vs. 65%; P = n.s.).

CONCLUSIONS

Elderly patients are at increased risk for significant DDIs when treated with DAAs for chronic HCV infection. However, with careful pre-treatment assessment of concomitant medications, on-treatment monitoring or dose-modifications, significant DDIs and associated adverse events can be avoided.

Alveolar and serum concentrations of imipenem in two lung transplant recipients supported with extracorporeal membrane oxygenation

Venovenous extracorporeal membrane oxygenation (ECMO) is increasingly used in patients with respiratory failure who fail conventional treatment. Postoperative pneumonia is the most common infection after lung transplantation (40%). Imipenem is frequently used for empirical treatment of nosocomial pneumonia in the intensive care unit. Nevertheless, few data are available on the impact of ECMO on pharmacokinetics, and no data on imipenem dosing during ECMO. Currently, no guidelines exist for antibiotic dosing during ECMO support. We report the cases of 2 patients supported with venovenous ECMO for refractory acute respiratory distress syndrome following single lung transplantation for pulmonary fibrosis, treated empirically with 1 g of imipenem intravenously every 6 h. Enterobacter cloacae was isolated from the respiratory sample of Patient 1 and Klebsiella pneumoniae was isolated from the respiratory sample of Patient 2. Minimum inhibitory concentrations of the 2 isolated strains were 0.125 and 0.25 mg/L, respectively. Both patients were still alive on day 28. This is the first report, to our knowledge, of imipenem concentrations in lung transplantation patients supported with ECMO. This study confirms high variability in imipenem trough concentrations in patients on ECMO and with preserved renal function. An elevated dosing regimen (4 g/24 h) is more likely to optimize drug exposure, and therapeutic drug monitoring is recommended, where available. Population pharmacokinetic studies are indicated to develop evidence-based dosing guidelines for ECMO patients.

Modulation of replication efficacy of the hepatitis C virus replicon Con1 by site-directed mutagenesis of an NS4B aminoterminal basic leucine zipper

The hepatitis C virus (HCV) nonstructural protein 4B (NS4B) is assumed to function as a membrane anchor and protein hub for the viral replication complex. The aim of the current work was to modulate HCV replication efficacy in the subgenomic Con1 replicon by mutations of specific sites within the aminoterminal-located basic leucine zipper (bZIP), a candidate motif for protein-protein interactions involving NS4B. Mutational sites and amino acid substitutes were determined by in-silico sequence analyses of the NS4B-bZIP motif in 357 isolates of HCV genotype 1b from the euHCVdB and LosAlamos database and consecutive analysis of conserved physico-chemical properties at bZIP specific positions. Mutants with predicted minor, medium or major reduction of replication efficacy were tested in the pFKI389neo/NS3-3'/ET plasmid replicon model. Four sites (L25, T29, V39 and W43) of crucial importance for bZIP-mediated protein interaction with predicted apolarity of respective amino acid positions were selected for mutational studies. Substitutes with physico-chemical properties matching the predicted requirements either well (T29A), moderately (L25W, V39W), or insufficiently (T29E, W43E) were associated with slightly improved, moderate and marked decreased replication efficacy, respectively. Spontaneous (T29G) and adaptive (A28G, E40G) mutations occurred in the T29E mutation isolate only and were associated with marked reduction of replication efficacy. The bZIP motif region of NS4B is crucial for RNA replication in the subgenomic Con1 replicon system. RNA replication efficacy can be modulated by site-directed mutagenesis at specific bZIP functional sites. New adaptive amino acid mutations were identified within the HCV NS4B protein.

Extension of the measurement capabilities of the quadrupole resonator

The quadrupole resonator, designed to measure the surface resistance of superconducting samples at 400 MHz has been refurbished. The accuracy of its RF-dc compensation measurement technique is tested by an independent method. It is shown that the device enables also measurements at 800 and 1200 MHz and is capable to probe the critical RF magnetic field. The electric and magnetic field configuration of the quadrupole resonator are dependent on the excited mode. It is shown how this can be used to distinguish between electric and magnetic losses.

Comparison of envelope 2 CD81 binding regions in PBMC-derived versus serum-derived hepatitis C virus isolates: higher conservation of CD81 region 2 in PBMC isolates

The aim of the present study was to investigate the variability of hepatitis C virus (HCV) CD81 binding regions (CD81-1/2) in peripheral blood mononuclear cells (PBMC)-derived and serum-derived HCV-RNA samples. HCV-RNA was isolated from PBMC (10⁴ cells) and serum samples from 37 patients chronically infected with HCV genotype 1a/1b (n=21/16). The hypervariable regions 1/2 (amino acid 384-410, amino acid 474-482) and regions CD81-1/2 (amino acid 474-494, amino acid 522-551) were analysed. Mutational frequency of amino acid sequences was compared between PBMC-derived and serum-derived HCV variants as well as local accumulation of mutations. Furthermore, CD81 was quantified on PBMC. Mutational frequency was not different between PBMC-derived and serum-derived HCV variants. A trend to lower mutational frequency in genotype 1a PBMC variants compared with serum-derived variants was observed in region CD81-2 (5%vs 10%). Smoothed mutational frequency analysis showed a significantly lower variability within genotype 1a CD81-2 in PBMC-derived compared to serum-derived HCV-RNA (P=0.026). CD81 expression on PBMC was not correlated with the number of mutations within the CD81 binding regions.

CONCLUSION

A higher conservation was observed in region CD81-2 in PBMC-derived versus serum-derived HCV-RNA indicating selection of HCV variants on PBMC. The variability in the CD81 binding regions appeared to be independent from CD81 expression.

Effect of ribavirin on the frequency of RNase L cleavage sites within the hepatitis C viral genome

The mechanisms of synergy in antiviral activity of interferon-alpha and ribavirin in treating chronic hepatitis C virus (HCV) infection are still unknown. Interferon-alpha indirectly induces cleavage of viral RNA by RNase L at UU/UA dinucleotides. There is evidence that HCV genomes with a higher number of UU/UA dinucleotides are more sensitive to interferon-alpha. As a guanosine analogue, ribavirin exerts a mutagenic effect promoting G-to-A and C-to-U transitions. This study investigates whether ribavirin-induced mutagenesis causes a higher frequency of UU/UA dinucleotides in the viral progeny sequences. Increased mutational frequencies in favour of G-to-A and C-to-U transitions during ribavirin treatment was reported by Hofmann et al. (Gastroenterology 2007;132:921-930). Overall, 937 nucleotide sequences from that publication were reanalysed for RNase L cleavage sites. These included HCV NS3 quasispecies from three patients with ribavirin monotherapy and NS5B quasispecies from patients who received ribavirin alone (n = 7) or in combination with interferon-alpha (n = 7) at baseline and during treatment; NS5B quasispecies from a subgenomic HCV replicon system after 24, 48 and 72 h of cultivation with or without ribavirin or with levovirin. For NS3 quasispecies during ribavirin monotherapy and NS5B quasispecies from patients who received ribavirin alone or in combination with interferon-alpha, analysis of RNase L cleavage sites did not reveal changes during treatment or differences between treatment regimes. Similarly, RNaseL cleavage sites from NS5B quasispecies of the HCV replicon did not differ significantly between time points or treatments. In conclusion, Ribavirin-induced mutagenesis did not increase RNase L cleavage sites (UU/UA dinucleotides) within the HCV NS3 or NS5B encoding regions.

Primary actinomycosis of the liver mimicking malignancy

A 71-year old women presented with fever, a significant loss of body weight and abdominal pain in the upper right quadrant since approximately six months. Abdominal ultrasonography and magnetic resonance imaging (MRI) showed an irregularly shaped, inhomogeneous and hypointense lesion of the right liver lobe (6 x 8 cm in segment 7 and 8) with multiple satellite lesions. Irregular shape, hypovascular presentation during gadolinium enhancement, hypointensity in T 1-weighted images and dilation of peripheral bile ducts were suggestive for cholangiocarcinoma or metastasis. However, histological investigations revealed a rare case of primary actinomycosis of the liver which was successfully treated with antibiotics.

[Myocarditis or subendocardial myocardial infarction: role of MRI illustrated by a case report]

A 50-year-old male patient treated with mesalazine for Crohn's disease was admitted in our unit for a chest pain, associated with nonspecific ST depression or ECG and troponin elevation. Coronarography showed minimal changes while SPECT imagery suggested a posterobasal subendocardial infarction, so that the diagnosis was unclear between ischemic disease and mesalazine-induced myocarditis. Eventually, MRI demonstrated clearly a subendocardial posterior infarction eliciting the diagnosis of mesalazine-induced myocarditis. This case report illustrates, in our opinion, that MRI is of invaluable interest in evaluating the characteristics of myocardium, and must be the cornerstone in the diagnosis of myocardial diseases.

Somatic hypermutation and mRNA expression levels of the BCL-6 gene in patients with hepatitis C virus-associated lymphoproliferative diseases

Chronic hepatitis C virus (HCV) infection leads to mixed cryoglobulinaemia (MC) and B-cell non-Hodgkin lymphoma (B-NHL). Aberrant somatic hypermutation and deregulation of the oncogene BCL-6 is associated with lymphomagenesis. Recently, HCV was shown to induce BCL-6 mutations in vitro. The BCL-6 gene (area B) was cloned and sequenced from peripheral blood mononuclear cells (PBMC) of 21 chronically HCV-infected patients with or without MC and B-NHL, and six healthy controls. Mutational frequencies, genetic complexity and diversity were calculated. BCL-6 mRNA from PBMC was quantified by real-time polymerase chain reaction, and additional sustained virologic responders to antiviral therapy and HBV patients served as controls. The overall/recurrent mutational frequencies tended to be lower in MC and B-NHL patients when compared with controls (P = 0.15 and 0.06, respectively). Genetic complexity was significantly lower in MC and B-NHL patients (P = 0.025). BCL-6 mRNA concentration was decreased in all HCV patients when compared with healthy controls, sustained virologic responder and HBV patients (P = 0.005). Although HCV can induce BCL-6 mutations in vitro, lower mutational frequencies and decreased BCL-6 mRNA expression in vivo suggest no major role of aberrant somatic hypermutation in HCV-associated MC and B-NHL.

Correlation of amino acid variations within nonstructural 4B protein with initial viral kinetics during interferon-alpha-based therapy in HCV-1b-infected patients

Chronic hepatitis C is a major cause of liver cirrhosis leading to chronic liver failure and hepatocellular carcinoma. Different hepatitis C virus (HCV) proteins have been associated with resistance to interferon-alpha-based therapy. However, the exact mechanisms of virus-mediated interferon resistance are not completely understood. The importance of amino acid (aa) variations within the HCV nonstructural (NS)4B protein for replication efficiency and viral decline during the therapy is unknown. We investigated pretreatment sera from 42 patients with known outcome to interferon-based therapy. The complete NS4B gene was amplified and sequenced. Mutational analyses of predicted conformational, functional, structural and phylogenetic properties of the deduced aa sequences were performed. The complete NS4B protein was highly conserved with a median frequency of 0.015 +/- 0.009 aa exchanges (median +/- SD, 4.00 +/- 2.31). Especially within the predicted transmembranous domains of the NS4B protein, the mean number of aa variations was low (median frequency, 0.013 +/- 0.013). Neither the number of aa variations nor specific aa exchanges were correlated with HCV RNA serum concentration at baseline. A rapid initial HCV RNA decline of >/=1.5 log(10) IU/mL at week 2 of interferon-based therapy was associated with a higher frequency of nonconservative aa exchanges within the complete NS4B protein in comparison with patients with a nonrapid HCV RNA decline (median frequency, 0.011 +/- 0.005 vs 0.004 +/- 0.003, P = 0.006). Overall, the aa sequence of the NS4B protein was highly conserved, indicating an important role for replication in vivo. Amino acid variations with relevant changes of physicochemical properties may influence replication efficiency, associated with a rapid early virological response.

The mutagenic potential of madder root in dyeing processes in the textile industry

The roots of Rubia tinctorum L. have a long tradition of being used in dyeing processes of textiles from centuries ago until the present time. The colouring principles belong to the class of hydroxyanthraquinones. Concern arose because several of these compounds were recognised as mutagenic in vitro and even carcinogenic in rodents. To assess the possible risk to humans caused by coloured textiles, mutagenicity was investigated with two madder root samples of different origin (Iran and Bhutan) along the entire dyeing process from root extracts to the dyed wool. The Salmonella/microsome test (Ames assay) with the strains TA98, TA100 and TA1537 was used. Significant mutagenic effects could be detected in madder root extracts and also in the final product, the dyed wool. Madder root from Iran showed considerably higher mutagenic responses than samples from Bhutan. Analytical investigations of the extracts by HPLC showed the presence of a spectrum of anthraquinones typical for madder root. Three mutagenic compounds, lucidine, rubiadine and purpuroxanthine, together with the non-mutagenic alizarine could be detected. The mutagenic response of the different samples was positively correlated with the concentration of the mutagenic anthraquinones, and with lucidine in particular. Based on these investigations a risk to dye-house workers and users of textiles dyed with R. tinctorum must be anticipated.

Mutations in the putative HCV-E2 CD81 binding regions and correlation with cell surface CD81 expression

The hepatitis C virus (HCV) envelope (E)2 protein interacts with the cellular receptor CD81 leading to modulation of B and T cell function. Recently, a higher binding affinity of subtype 1a in comparison with 1b derived E2 proteins for CD81 in vitro was described. The importance of mutations within the putative CD81 binding regions of different HCV geno-/subtypes in correlation with CD81 expression is unknown. In the present study, CD81 expression on blood lymphocytes of patients with chronic hepatitis C infected with different HCV geno-/subtypes were analysed by fluorescence activated cell sorter analyses. In addition, the putative CD81 binding regions on the E2 gene comprising the hypervariable region (HVR)2 were analysed by direct sequencing. CD81 expression on CD8(+) T-lymphocytes from patients infected with subtype 1a (n = 6) was significantly higher in comparison with subtype 1b (n = 12) and 3 (n = 5) infected patients before and during antiviral therapy (P = 0.006; P = 0.021, respectively). Sequencing of the putative CD81 binding regions in the E2 protein comprising the HVR2 (codon 474-495 and 522-552 according to the HCV-1a prototype HCV-H) showed a highly conserved motif within HVR2 for subtype 1a isolates and an overall low number of mutations within the putative CD81 binding regions, whereas numerous mutations were detected for subtype 1b isolates (12.0 vs 23.6%). HCV-3 isolates showed an intermediate number of mutations within the putative binding sites (19.2%; P = 0.022). In conclusion, the highly conserved sequence within HVR2 and putative CD81 binding sites of subtype 1a isolates previously associated with a high CD81 binding affinity in vitro is correlated with high CD81 expression on CD8(+) T-lymphocytes in vivo.

[Ramipril and cardiac and renal angiotensin converting enzyme]

The role of the angiotensin converting enzyme (ACE) in the regulation of local synthesis of angiotensin II has not been clearly defined. The authors investigated the local factors which might orientate the effects of ACE inhibitors to particular organs in the Wistar rat. The in vivo study of the effects of low doses of ramipril on the myocardium showed that cardiac ACE was significantly inhibited by the non-antihypertensive dose of 0.01 mg/kg whereas the inhibition only occurred from doses higher than 0.1 mg/kg in the other tissues studied. In the kidney: the affinity of 3H-ramiprilate for the brush borders of the proximal tubular cells was increased by high concentrations of chloride ions as observed in the renal parenchyma, the presence of esterases makes local activation of ramipril (diester) into ramiprilate (active diacid) possible, prolonged treatment with ramipril leads to a lowering of the concentration of ACE in the brush border of the proximal tubular cells, verified after the elimination of the ACE inhibitor fixed on the tissue. These data indicate that the myocardium and the kidney could be privileged targets of the action of ramipril.

Influence of dietary-fat on growth of mda-mb231 human breast carcinomas maintained in female athymic nude-mice

The purpose of this study was to assess the effects of the type of dietary fat [corn oil (controls), olive oil, linseed oil, primrose oil, canola oil and fish (Menhaden) oil] and the amount of dietary fat on the growth of MDA-MB231 human breast carcinomas in female athymic nude mice. The different types of fats examined in these studies differ widely in their omega-3, -6 and -9 fatty acid contents, fatty acid chain length and their degree of unsaturation. These fats were fed to the carcinoma bearing mice at 20% of the diet by weight and for 5 to 8 weeks. No significant effect of these diets on mouse body weight gains throughout the study was observed. Compared to the corn oil controls, none of the dietary fats significantly affected the growth of the human breast carcinomas in these animals, with the exception of fish oil which consistently and significantly (P<0.05 to P<0.001) suppressed carcinoma growth. DNA synthesis of the human breast carcinomas derived from the fish oil fed mice was assessed by BrdU and PCNA labeling indices and by H-3-thymidine autoradiographic analysis. Despite the fact that the carcinomas derived from the fish oil fed mice were significantly smaller than the carcinomas from the corn oil fed mice, there were no significant differences in any of these parameters of DNA synthesis between the two groups (corn oil and fish oil) of carcinomas. In contrast, in the human breast carcinomas derived from the fish oil fed mice, a significant increase (P<0.01 to P<0.001) in the rate of (125)IUrd loss (K-L/day) and a significant increase (P<0.05 to P<0.001) in the cell loss factor (phi) (phi=1-T-P/T-D) was observed, compared to carcinomas derived from corn oil fed mice. Analysis of the human breast carcinomas for TBARS, a measure of secondary products of lipid peroxidation, revealed that the carcinomas derived from the fish oil fed mice had significantly increased (P<0.001) concentrations of these products compared to carcinomas derived from corn oil fed mice. These results provide evidence that the suppression of growth of human breast carcinoma MDA-MB231 in athymic nude mice by dietary fish oil appears to be due primarily to an increase in the loss of cells from the carcinomas in lieu of a suppression of DNA synthesis, a phenomenon that may be due to the increased concentration of lipid peroxidation products in the tumor tissue. In the studies designed to examine the effect of the amount of fat on growth of MDA-MB231 human breast carcinomas in athymic nude mice, one group of mice was fed a high fat diet (corn oil, 29%) and a second group of mice was fed a low fat diet (corn oil, 1.8%). Both diets were fed at a restricted level, i.e., 65% of ad libitum. A third group of mice was fed a high fat diet (corn oil, 18.1%) ad libitum. The diets were formulated to assure that mice of each group consumed equal amounts of protein, vitamins, minerals and fiber; mice fed the high fat diets (ad libitum and restricted) consumed equal amounts of fat. Growth of the human breast carcinomas in mice fed the high fat and low fat restricted diets was not significantly different despite the large difference in fat consumption. Growth of the carcinomas in mice fed the high fat diet ad libitum was substantially greater than carcinoma growth in mice fed the restricted high fat diet (P<0.001) despite equal amounts of fat consumption. These results demonstrate that in an environment of energy (caloric) restriction, high levels of dietary fat will not enhance growth of MDA-MB231 human breast carcinomas in athymic nude mice, thus emphasizing the important role for energy (calories) in the enhancement of mammary (breast) tumorigenic processes by high fat diets.

Effects of triiodothyronine and dexamethasone on plasma and tissue angiotensin converting enzyme in the rat

In order to identify tissue specific regulation of angiotensin converting enzyme (ACE), the effects of dexamethasone (0.04 mg sc per day for 7 days) and triiodothyronine (T3) (0.5 mg/kg sc per day for 10 days) on ACE activity were investigated in different tissues in male Wistar rats. ACE activity was measured by fluorimetry in the plasma, heart, lung and kidney. In the kidney, ACE activity was measured in the medulla, cortex and brush border of proximal tubular cells and 3H-ramiprilat binding was used to characterise the changes in brush border ACE activity. Dexamethasone elicited a significant increase in lung ACE activity and a significant decrease in plasma ACE activity, but did not alter enzyme activity in the other tissues studied. T3 produced a significant decrease in lung ACE activity and an increase in ACE activity in the plasma and heart. In the kidney, ACE activity was not modified in the medulla whereas in the cortex and brush border ACE activity was doubled. This increase in ACE activity corresponded to a similar increase in the maximum number of binding sites of 3H-ramiprilat, suggesting that the increase in activity corresponded to an increase in the ACE level. The increased heart and kidney ACE activity in response to T3 may contribute to the cardiovascular effects of thyroid hormones through increased local angiotensin II generation. These results show that under dexamethasone or T3, ACE activity can vary from one tissue to another, suggesting that the ACE regulatory mechanism acts differently in each tissue.

Effects of dietary protein and uninephrectomy on renal angiotensin converting enzyme activity in the rat

This study examines the effects of dietary protein and of uninephrectomy on angiotensin converting enzyme (ACE) in the normotensive rat, with particular regard to the kidney. Male Wistar Kyoto rats were fed isocaloric diets containing 5, 16 or 50% protein for three weeks. Other groups of rats were subjected to either left unilateral nephrectomy or sham operations, and the rats were killed eight days after surgery. ACE activity was measured in the kidney medulla, cortex, proximal tubule brush border membrane and in the plasma, heart and lung. Renal cortex and brush border ACE activity increased in parallel with protein intake, whereas plasma and lung ACE activity decreased; heart and kidney medulla ACE activity did not vary significantly. Uninephrectomy also led to a high increase in brush border ACE activity in the contralateral kidney, with no effect in the renal medulla or in the other tissues. The increase in ACE activity in the brush border membrane corresponded to a similar increase in the maximum number of binding sites of 3H-ramiprilat. This suggested that the increase in ACE activity corresponded to an increase in ACE concentration. The increase in renal tubular ACE activity could result in higher angiotensin II levels, and could consequently play a role in the modification of sodium reabsorption and cellular growth which occurs in the proximal tubule in these experimental models.

Plasma renin activity and changes in tissue angiotensin converting enzyme

OBJECTIVES

Recent evidence suggests that tissue generation of angiotensins I and II depends on the level of the plasma components of the renin-angiotensin system and on tissue-specific processes. The present study was undertaken to clarify the possible relationship between plasma renin activity (PRA) and tissue angiotensin converting enzyme (ACE) activity in the heart, lung, kidney cortex and kidney medulla of Wistar-Kyoto rats. In the kidney cortex particular attention was focused on renal brush-border ACE.

METHODS

Different experimental models known to have opposite effects on PRA were used: changes in salt intake, deoxycorticosterone acetate (DOCA) with or without salt supplements, and the Goldblatt two-kidney, one clip (2-K,1C) model. Two weeks after the start of the experiments the rats were killed, and PRA, and plasma and tissue ACE activity, were measured.

RESULTS

At the end of the study the blood pressure in the treated rats was not significantly different from control. As expected, the PRA were highest in the 2-K,1C and depleted-salt groups and lowest in the DOCA, DOCA-salt and high-salt groups. ACE responses were different in different types of tissue, with no relationship between PRA and plasma or tissue ACE activity. For example, DOCA treatment led to increased ACE activity in the heart and the kidney only if the rats were maintained on a high salt intake. DOCA or salt alone failed to have this effect. In the 2-K,1C model the unclipped kidneys did not show any significant variation in ACE activity, but the clipped kidneys exhibited increased ACE activity compared with sham-operated rats. This increase, coupled with increased renal renin secretion, could play a role in the acceleration of local angiotensin II formation, and could thus initiate and sustain the development of hypertension in this model.

CONCLUSION

The present results show that variations in ACE activity were organ-specific and were not linked either to hypertension or to changes in PRA.

[Plasma renin activity and angiotensin converting enzyme of renal brush borders]

The present experiment was undertaken to examine the relationship between plasma renin activity and the concentration of angiotensin converting enzyme (ACE) in plasma and renal brush border of Wistar Kyoto rats. Different experimental models known to have opposite effects on plasma renin activity were used: changes in salt intake, the deoxycorticosterone acetate (DOCA) and DOCA-salt models and the two-kidneys one clip (2K1C) model. Two weeks after the start of these experimental series, the rats were killed. At this time, blood pressure did not differ from control group, even in the 2K1C and DOCA-salt groups. As expected, PRAs were highest in the 2K1C and depleted salt groups and lowest in the DOCA, DOCA-salt and high salt groups. No relationship between this wide variation in PRA and change of ACE activity in both plasma and renal brush border could be observed. In the plasma, ACE activity in sodium-depleted rats was slightly decreased whereas no change occurred in the other models. In the kidney, DOCA treatment led to increased ACE activity in the brush border only if the animals were maintained on a high salt intake. DOCA or NaCl alone failed to have this effect. In the 2K1C model, the clipped kidneys exhibited increased brush border ACE activity whereas the unclipped kidneys did not show any significant variation in ACE activity, when compared to sham operated rats. In summary, on one hand these findings show that variations in ACE activity were linked neither to hypertension nor to changes in PRA.(ABSTRACT TRUNCATED AT 250 WORDS)

Oncology nurse and physician attitudes toward aggressive cancer treatment

Oncology nurses (n = 57) and oncology physicians (n = 40) employed in the same hospital completed the Cancer Attitude Questionnaire. Significant differences (p < or = .001) between nurse and physician attitudes were evident on the two major subscales addressing the issues of (a) aggressiveness of treatment/de-emphasis of socioemotional aspects of care and (b) the importance of patient-family attitudes. Physicians' attitudes were significantly more favorable on the first subscale; nurses' attitudes were significantly more favorable on the second. Implications of these findings as indicators of potential nurse-physician conflict are discussed.

Angiotensin converting enzyme variability in hypertensive and normotensive rats

Recent data have revealed biological and genetic variability in normotensive Wistar-Kyoto rats, which are considered to be the most appropriate control strain for spontaneously hypertensive rats. To investigate the possibility that angiotensin converting enzyme activity could be affected by this variability, we measured plasma and tissue (lung, heart, renal cortex, renal medulla, and adrenal gland) angiotensin converting enzyme activity in spontaneously hypertensive rats and normotensive Wistar-Kyoto rats from three commercial suppliers in France: Iffa-Credo, Janvier, and Charles River Laboratories. Angiotensin converting enzyme activity was measured in vitro with a fluorometric assay using carbobenzoxy-Phe-His-Leu as substrate. Angiotensin converting enzyme activity in both rat strains varied considerably from one supplier to another, and therefore, comparisons of spontaneously hypertensive rats and Wistar-Kyoto rats from the different suppliers produced conflicting results. For Wistar-Kyoto rats, angiotensin converting enzyme activity in the plasma, heart, kidney, and adrenal glands was highest in rats from Iffa-Credo and lowest in rats from Charles River. For spontaneously hypertensive rats, angiotensin converting enzyme activity in the plasma and tissues was highest in rats from Janvier, whereas no difference could be observed between rats from Iffa-Credo and Charles River. These data confirm the problem of how to interpret and compare studies that use spontaneously hypertensive and Wistar-Kyoto rat strains.

ENU-induced in vitro neoplastic transformation of rat mammary epithelial cells

Normal mammary epithelial cells, originating from female Sprague-Dawley rats, were grown in Dulbecco's Modified Eagles Medium containing 25% horse serum and hormone supplements. Once established as an epithelial cell culture, the cells were treated with N-ethyl-N-nitrosourea (ENU) in various doses (25-500 ug/ml) to study the process of in vitro mammary epithelial cell neoplastic transformation. The ENU-treatment of primary mammary epithelial cell culture resulted in a sequence of phenotypic changes, termed stages I-V. The rat mammary epithelial cells, after a period of approximately 30 days post-ENU exposure, showed a marked proliferation of morphologically altered cells which formed multi-layered colonies. Subsequently, these cells acquired the capacity to form colonies in soft agar and eventually produced a high yield of palpable tumors when inoculated into newborn female isologous hosts or female athymic nude mice. The immediate effect of ENU on these cells was monitored by measurement of cellular DNA content, unscheduled DNA synthesis, cell proliferation and chromosomal aberrations. The ENU effect on cell proliferation and DNA synthesis was dose dependent; doses greater than 100 ug/ml reduced the cell number and DNA synthesis. Cytofluorometric histograms of non-ENU-treated rat mammary epithelial cells showed a near diploid population of cells. The ENU exposed cells subsequently became hyperdiploid (24-72 hours after ENU) and then regained their near diploid pattern at 120 hours after ENU exposure. The ENU-treated cells also showed a second peak of cells with DNA content in the tetraploid and octaploid range at 24-72 hours after ENU exposure. Single chromatid breaks, isochromatid breaks, chromosomal exchanges, multiple chromosomal breaks and double minutes were among the chromosomal aberrations seen in ENU-treated cells. Most of the chromosomal aberrations peaked at 6 hours post-ENU exposure. The ENU-induced model of in vitro meplastic transformation of rat mammary epithelium as described in this communication appears to provide a good model for the systematic study of the early critical cellular events prerequisite to this carcinogenic process.

[Changing factors of the activity of angiotensin converting enzyme of renal brush border in rats]

In the kidney, angiotensin I-converting enzyme (ACE) is present in the vascular endothelial cells and in the brush border of epithelial cells of the proximal tubule. In spite of this well-known distribution of ACE, little is known of its regulation. In order to elucidate the possible mechanisms of control for brush border ACE, the effects of dexamethasone (DM), (40 micrograms s.c. per day, for 7 days) and triiodothyronine (T3) 0.5 mg/kg s.c. per day, for 10 days) were investigated in male Wistar rats. Plasma and brush border ACE activities were measured by fluorimetry in the presence of an artificial substrate Cbz-Phe-His-Leu and brush border ACE was characterized with a binding assay using 3H-ramiprilat, a specific radiolabelled ACE inhibitor. DM elicited a significant decrease in plasma ACE activity (from 0.46 +/- 0.03 to 0.28 +/- 0.02 nmol His-Leu/min/mg protein) but did not alter enzyme activity in the brush border: 47.12 +/- 5.12 nmol His-Leu/min/mg protein (control, n = 6) and 47.78 +/- 5.63 (DM, n = 6). Administering T3 produced a marked increase in the brush border ACE activity (from 42.87 +/- 4.9 to 81.41 +/- 11.7 nmol His-Leu/min/mg protein). Similarly, the maximum number of 3H-ramiprilat-binding sites increased in the brush border, indicating a good correlation between ACE activity and the quantity of 3H-ramiprilat bound. Thus, the variation in tissue ACE activity corresponded to a change in the enzyme concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

In vitro tissue potencies of converting enzyme inhibitors. Prodrug activation by kidney esterase

The inhibition of angiotensin converting enzyme by ramipril, ramiprilat, enalapril, enalaprilat, and captopril was studied in the plasma and various tissues (lung, heart, renal cortex, renal medulla) of normotensive rats and spontaneously hypertensive rats. Displacement curves for [3H]ramiprilat were established on each tissue with the converting enzyme inhibitors, and their potencies were expressed as the concentration that inhibited 50% of the specific [3H]ramiprilat binding. In the plasma, lung, and heart, the order of activities was: ramiprilat greater than enalaprilat greater than captopril greater than ramipril greater than enalapril. This order was different in the kidney (cortex and medulla): ramiprilat greater than enalaprilat greater than ramipril greater than captopril greater than enalapril. For ramiprilat, enalaprilat, and captopril, there were no differences in their respective potencies between tissues or between rat strains. However, the two prodrugs ramipril and enalapril were 10-30 times more active in the kidney than in the other tissues in both groups of rats. This was due to the deesterification of the prodrugs: in the presence of an esterase inhibitor (diethyl nitrophenyl phosphate, 10 microM), the potencies of ramipril in the kidney were not different from that obtained in the lung, which was not affected by the presence of the esterase inhibitor. These results suggest that the variations in the tissue activities of an angiotensin converting enzyme inhibitor are probably not due to differences in tissue affinities of the angiotensin converting enzyme inhibitor but depend on the concentration of this angiotensin converting enzyme inhibitor in each tissue.

[3H]ramiprilat binding to the angiotensin-converting enzyme in rat renal brush-border membranes: the effect of chloride

The [3H]ramiprilat binding to the angiotensin-converting enzyme (ACE) in rat renal brush-border membranes was studied. At pH 7.9, and in the presence of 50 mM NaCl, specific binding of [3H]ramiprilat was saturable with a dissociation constant KD = 5.05 nM and maximum number of binding sites of 1.52 pmol/mg prot. [3H]Ramiprilat binding was completely inhibited by specific inhibitors of ACE: ramiprilat, ramipril, enalaprilat, enalapril and captopril. [3H]Ramiprilat binding was Zn2(+)- and Cl(-)-dependent. In the presence of EGTA, which chelates Zn2+ ions, ramiprilat binding was inhibited, but the addition of Zn2+ restored the initial binding. Binding was maximum in the presence of 10 mM NaCl while higher NaCl concentrations decreased the binding, corresponding to a decrease in affinity. The association and dissociation kinetics were also NaCl-dependent. In the absence of NaCl, association and dissociation kinetics were rapid and monophasic. Two-step dissociation kinetics appeared in the presence of 10, 50 and 300 mM NaCl and dissociation time increased with the NaCl concentration. These results confirmed the role of Cl- in the isomerisation and the stability of the membrane-associated ACE-inhibitor complex.

Age-related variations in tissue angiotensin converting enzyme activities: comparison between spontaneously hypertensive and Wistar-Kyoto rats

Angiotensin converting enzyme (ACE) activity was measured by fluorimetry in the plasma, lung, heart, aorta and kidney (cortex and medulla) of 3-, 5-, 8- and 11-week-old spontaneously hypertensive rats (SHR) and compared with that of age-matched Wistar-Kyoto rats (WKY). In the plasma, lung and kidney (cortex and medulla), ACE activity was lower in SHR than in WKY. This was evident as early as the age of 3 weeks. In contrast, there were no differences between SHR and WKY in the aorta and the heart. Age-related variations in ACE activities differed in each tissue and in both groups of rats, but no major modifications were correlated with the development of hypertension. A binding assay was performed with [3H]ramiprilat; affinity (KD) and the maximum number of binding sites (Bmax) were determined in plasma and tissues of 3-week-old SHR and WKY. The KD values were identical in the two groups but Bmax was lower in all SHR tissues except in the heart; these results might be related to the decrease in ACE activity. Our results probably reflect genetic differences in ACE activity between SHR and WKY, and suggest that ACE regulatory mechanisms act differently in each tissue.

Binding of loop diuretics to their renal receptors: use as a screening model for potential diuretic activity

Loop diuretics of the benzoic acid and aryloxyacetic acid families inhibit Na+K+Cl- cotransport. The ranking order of potencies measured in the thick ascending limb of Henle's loop and the ranking order of affinities for [3H]piretanide receptors on renal plasma membranes are the same. Potencies and affinities correlate well (correlation coefficient r = 0.959 for the medulla and r = 0.951 for the cortex). Therefore, measurement of [3H]piretanide binding is proposed to facilitate screening for loop diuretic action.

Tissue converting enzyme activity is low in the kidney of spontaneously hypertensive rats

Angiotensin-converting enzyme (ACE) activity was measured in the plasma, the kidney, and other organs of 5-, 8-, and 11-week-old spontaneously hypertensive male rats (SHR) of the Okamoto-Aoki strain and compared with that of age-matched Wistar-Kyoto (WKY, bred by Iffa-Credo) or normotensive Wistar rats. ACE activity was measured spectrofluorometrically, using the artificial substrate N-CBZ-L-phe-L-his-L-leu. ACE activity was constantly lower in the plasma and renal cortex of SHR from 5 weeks on than in WKY rats. This difference in the renal cortex ACE activity persisted after 1 h of open circuit perfusion of the isolated kidney with Krebs-Henseleit medium. On the other hand, there lung, the brain occipital cortex, or the abdominal aorta of hypertensive or normotensive rats. The percentage inhibition of ACE activity provoked by 7 days of oral administration of ramipril (Hoe 498, 1 mg/kg/day) was analogous in the kidneys and lungs of WKY rats and SHR. Enalapril (MK 421, 30 mg/kg/day) was equipotent to ramipril in the kidney but had lower inhibitory effects on the pulmonary ACE activities of WKY rats and SHR.

Effect of angiotensin converting enzyme inhibitors on the vasoconstrictor action of angiotensin I on isolated rat kidney

On the isolated perfused rat kidney, the angiotensin converting enzyme (ACE) activity was evaluated with two approaches: one, pharmacological, through the vasoconstrictor response to angiotensin I (ANG I), and the other, biochemical, through the measurements of the enzymatic activity on renal homogenate. ANG I and angiotensin II (ANG II) induced a concentration-dependent renal vasoconstriction (EC50 = 10.5 +/- 1.8 X 10(-9) and 1.1 +/- 0.5 X 10(-9) M, respectively). Both responses were competitively antagonized by an ANG II receptor antagonist, saralasin (pA2 = 8.65 +/- 0.63 and 8.94 +/- 0.28, respectively). The effects of ACE inhibitors were studied in vitro after addition of captopril and ramiprilat (10(-5) M) directly to the perfusion medium, and ex vivo, after pretreatment of the rats with ramipril (50 mg/kg, i.p. the day before or 10 mg/kg/day, per os, over 3 weeks). In spite of the high doses of ACE inhibitors used, the ANG I concentration-response curve was only shifted to the right by a factor of 4, although renal tissue ACE activity was completely inhibited. Saralasin (10(-5) M) totally abolished the ANG I-induced vasoconstriction elicited in the presence of ACE inhibitors, this response being therefore linked to a generation of ANG II from ANG I. Our results suggest that, on the isolated perfused rat kidney, ANG II may be formed from ANG I by a peptidyl dipeptidase different from the ACE.

Characterization of a high affinity piretanide receptor on kidney membranes

The tritiated loop diuretic, piretanide, is a useful ligand for specific diuretic receptors which are present in the plasma membranes of renal medullary cells. Its high specific activity (30 Ci X mmol-1) made it possible to demonstrate the existence of a high affinity receptor (Kd approximately 5 nM) and a binding site with low affinity. High affinity binding is saturable, reversible and displaceable by a number of non-radioactive loop diuretics. Structural analogues, devoid of diuretic activity, do not displace piretanide binding. No specific binding occurs in liver or spleen membranes.

Whole body protein synthesis and energy expenditure in very low birth weight infants

The aim of the present work was to study whole body protein synthesis and breakdown, as well as energy metabolism, in very low birth weight premature infants (less than 1500 g) during their rapid growth phase. Ten very low birth weight infants were studied during their first and second months of life. They received a mean energy intake of 114 kcal/kg X day and 3 g protein/kg X day as breast milk or milk formula. The average weight gain was 15 g/kg X day. The apparent energy digestibility was 88%, i.e. 99 kcal/kg X day. Their resting postprandial energy expenditure was 58 kcal/kg X day, indicating that 41 kcal/kg X day was retained. The apparent protein digestibility was 89%, i.e. 2.65 g/kg X day. Their rate of protein oxidation was 0.88 g/kg X day so that protein retention was 1.76 g/kg X day. There was a linear relationship between N retention and N intake (r = 0.78, p less than 0.001). The slope of the regression line indicates a net efficiency of N utilization of 67%. Estimates of body composition from the energy balance, coupled with N balance method, showed that 25% of the gain was fat and 75% was lean tissue. Whole body protein synthesis and breakdown were determined using repeated oral administration of 15N glycine for 60-72 h, and 15N enrichment in urinary urea was measured. Protein synthesis averaged 11.2 g/kg X day and protein breakdown 9.4 g/kg X day. Muscular protein breakdown, as estimated by 3-methylhistidine excretion, contributed to 12% of the total protein breakdown.(ABSTRACT TRUNCATED AT 250 WORDS)

Relationship of the menstrual cycle and thyroid hormones to whole-body protein turnover in women

Whole-body protein turnover was measured in eight women, using a single oral dose of 15N-glycine and urinary ammonia as the end product analysed. Energy and protein intakes were carefully controlled on the day of the measurement. Each subject was tested five or six times at weekly intervals. Four of the subjects were taking oral contraceptives, the other four were non-pill users. Values of whole-body protein turnover (flux) were within the range of previously reported data: 2.9-4.7 g/kg/d. Inter-individual variation was significantly greater than intra-individual variation. The latter ranged between 10 and 23 per cent. Protein turnover was significantly correlated with the serum T3/rT3 ratio (r = 0.845, P less than 0.01). No difference was found between pill users and non-pill users, nor between the luteal and the follicular phase of the menstrual cycle among non-pill users. These data suggest that the single-dose method with ammonia as the end product is suitable for human studies in clinical situations and that the phase of the menstrual cycle does not seem to be of critical importance when investigating menstruating women.

[Behavior of central venous pressure in different types of anesthesia under the administration of various coagulation inhibiting substances]

In a prospective study right atrial pressures and parameters of blood coagulation were monitored during anaesthesia and postoperatively in 60 surgical patients. 30 patients received spinal anaesthesia. 30 patients were intubated for general anaesthesia. One third of the patients in each group were injected with heparindihydroergotamine s.c., another third was infused with dextran 6% 500 ml, the remainder received no medication. Following dihydroergotamine s.c., right atrial pressures were increased, due to raised venous vascular tonicity and augmented venous return, which causes enddiastolic ventricular volume to rise. Dextran 500 ml had the same effect in right atrial pressures.

Energy expenditure and whole body protein synthesis in very low birth weight (VLBW) infants

To examine the rates of whole body protein synthesis and energy expenditure during the rapid growing period, premature infants of very low birth weight (VLBW) (less than 1500 g), appropriate for gestational age were kept under standard thermoneutrality conditions and received a formula diet providing 110 kcal/kg.d metabolisable energy (ME) and 3.3 g protein/kg.d. Their energy expenditure was measured by open circuit indirect calorimetry. Nitrogen turnover and whole body protein synthesis and catabolism were determined using repeated oral administration of 15N-glycine for 60-72 h followed by the analysis of 15N-enrichment in urinary urea. These VLBW infants grew at an average rate of 15 g/kg.d. About half of the ME intake (i.e. 50 kcal/kg.d) was invested in weight gain while the remainder (i.e. 60 kcal/kg.d) was oxidised. The energy equivalent of the weight gain (i.e. the amount of energy stored per g weight gain) and the N balance indicated that lean tissue made up approximately 2/3 of the weight gained and fat tissue the remaining 1/3. The plateau value for 15N enrichment reached on the third day of administration allowed us to calculate a rate of protein synthesis of 14 g/kg.d and protein breakdown of 12 g/kg.d in five VLBW fed a formula diet. The elevated energy expenditure of the very low birth weight infant seems to be related to its rapid rate of weight gain which is accompanied by a high rate of body protein synthesis. More than 20% of the total energy expenditure of the VLBW infants was accounted for by whole body protein synthesis.

Metabolism of L-sorbose in the rat and the effect of the intestinal microflora on its utilization both in the rat and in the human

L-[U-14C]-sorbose was administered orally as single doses to 5 normal rats. The recovery of radioactivity was 5.3% in the urine, 46% in the faeces exclusively as L-sorbose 16% as carbon dioxide. Caloric utilization was approximately 25%. A second group of 3 rats that had previously received L-sorbose in their diet showed 14C recoveries of 8.9% in the urine, 6.6% in the faeces and 59% as carbon dioxide. The time course of expired carbon dioxide suggests that a portion of L-sorbose was rapidly absorbed and partially metabolized while the principal pathway involved fermentation by the intestinal microflora to volatile fatty acids which were subsequently absorbed and metabolized. The total caloric utilization of L-sorbose was estimated to be 70%. It was observed that a human intestinal microflora also required an adaptation period in order to ferment this sugar. The efficiency of the fermentation was estimated to be 70%.

[Premedication with doxepin (author's transl)]

The effects of doxepin on the circulation and its anxiety relieving properties were studied in 67 patients who were premedicated with this drug before surgical operations. The findings showed that doxepin is very suitable for premedication on account of its sedative, tranquilizing and analgesic properties. It also reduced secretion of mucus and saliva. In a few cases it caused mild orthostatic circulatory dysregulation. The drug was well tolerated and has proved its value for routine administration.