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La epicondilitis es una entidad que provoca discapacidad y tiende a cronificar. Histológicamente, existen lesiones degenerativas en el tendón extensor común del antebrazo, visibles mediante ecografía o resonancia magnética.

El síndrome de dolor subacromial es un cuadro clínico caracterizado por dolor localizado alrededor del acromion que se desencadena o se exacerba con los movimientos del hombro. La ecografía es una técnica de imagen adecuada para evaluar los tejidos blandos que ocupan el espacio subacromial. El objetivo de este trabajo es describir los hallazgos ecográficos en pacientes diagnosticados de síndrome de dolor subacromial crónico relacionándolos con el sexo, la edad y el tiempo de evolución.

Direct‐acting antivirals have proved to be highly efficacious and safe in monoinfected liver transplant (LT) recipients who experience recurrence of hepatitis C virus (HCV) infection. However, there is a lack of data on effectiveness and tolerability of these regimens in HCV/HIV‐coinfected patients who experience recurrence of HCV infection after LT. In this prospective, multicenter cohort study, the outcomes of 47 HCV/HIV‐coinfected LT patients who received DAA therapy (with or without ribavirin [RBV]) were compared with those of a matched cohort of 148 HCV‐monoinfected LT recipients who received similar treatment. Baseline characteristics were similar in both groups. HCV/HIV‐coinfected patients had a median (IQR) CD4 T‐cell count of 366 (256‐467) cells/µL. HIV‐RNA was <50 copies/mL in 96% of patients. The DAA regimens administered were SOF + LDV ± RBV (34%), SOF + SMV ± RBV (31%), SOF + DCV ± RBV (27%), SMV + DCV ± RBV (5%), and 3D (3%), with no differences between the groups. Treatment was well tolerated in both groups. Rates of SVR (negative serum HCV‐RNA at 12 weeks after the end of treatment) were high and similar for coinfected and monoinfected patients (95% and 94%, respectively; P= .239). Albeit not significant, a trend toward lower SVR rates among patients with advanced fibrosis (P= .093) and genotype 4 (P= .088) was observed. In conclusion, interferon‐free regimens with DAAs for post‐LT recurrence of HCV infection in HIV‐infected individuals were highly effective and well tolerated, with results comparable to those of HCV‐monoinfected patients. Direct‐acting antivirals against HCV offer a very high and similar efficacy and safety in HIV‐positive and HIV‐negative liver transplant recipients.

The use of polymers for orthopedic implants and tissue engineering applications is leading to new frontiers, thanks to some characteristics, such as low specific weight, cost, and performance. In many occasions, it is widely sought for these polymeric devices to support bone ingrowth and to enhance the osseointegration with the remaining bone or tissue structure. Although atmospheric plasma spray is the most widely used technology to apply bioactive coatings and to accomplish these purposes, only a few studies are available regarding plasma sprayed coatings on polymers. The aim of this paper is to present results of experiments concerning bioactive plasma sprayed coatings on polymeric substrates, specifically on poly(ether ether ketone) (PEEK), a suitable material for orthopedic, and tissue engineering applications. Here, results are presented in terms of macro- and micro-structure analysis by scanning electron microscopy and X-ray diffraction as well as physico-chemical stability by X-ray photoelectron spectroscopy. The obtained data indicate a successful deposition of titanium dioxide and hydroxyapatite coatings on PEEK. Furthermore, the biocompatibility of these deposits was evaluated for osteoblast-like cells.

Prostate cancer is the most common malignancy in Mexican men. To improve its detection and prevent needless biopsies, we investigated the convenience of a combined analysis of prostate-specific antigen, androgen-receptor gene CAG repeats, and glutathione-S-transferase P1 and Ras association domain family 1 isoform A gene promoter methylation as a noninvasive option. The data from 186 patients who had undergone prostate biopsy were studied. The combined analysis increased detection confidence and could avoid unnecessary prostate biopsies.

There have been various forms of mesenchymal stem cell-like (MSC-like) cells isolated from umbilical cords (UCs). The isolation of umbilical cord lining stem cells (ULSCs) may be of great value for those interested in a possible treatment to several disease/disorders. Unlike umbilical cord blood cells, these cells are unique because they can be expanded to therapeutically relevant numbers and cryopreserved for several different uses. Here we efficiently isolate stem cells from a small segment of pre- and postnatal UCs, and obtain therapeutically relevant amounts of ULSCs within 3 weeks. We demonstrate their growth potential and characterize them using immunocytochemistry, flow cytometry, and RT-PCR. In addition, we differentiate ULSCs into multiple lineages. Pre- and postnatal ULSCs are morphologically similar to mesenchymal stem cells (MSCs) and easily expand to greater than 70 population doublings. They express pluripotent markers Oct4 and nanog at the protein and RNA level. Flow cytometry demonstrates that they express markers indicative of MSCs in addition to high SSEA-4 expression. ULSCs are easily differentiated into osteogenic, adipogenic, chondrogenic, cardiogenic, and neurogenic cells. Pre- and postnatal ULSCs are characteristically similar in respect to their growth, marker expression, and plasticity, demonstrating they are highly conserved throughout development. ULSCs have phenotypic and genotypic properties of MSCs. These studies demonstrate the therapeutic potential of an otherwise discarded tissue. They are a perfect HLA match for the donor and an excellent match for immediate family members; therefore, they may serve as a therapeutic cell source.

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AbstractNeutral beam injection (NBI) heating in the TJ-II stellarator faces the particular challenge of unwanted particle sources, which for relatively low injected powers drive the plasma to collapse at relatively low values of line density. This effect is aggravated by an enhancement of particle confinement that occurs as density increases. At present, candidate magnetic topologies that make use of intrinsic islands at the plasma edge are being investigated experimentally. This concept uses magnetic configurations having a rotational transform with a rational value at the edge, i.e., an island divertor (ID). Recently, impurity injection experiments have been performed for ID and limiter configurations to investigate the divertor effect in TJ-II. Indeed, the enhanced screening of injected impurities, as well as the low intrinsic plasma contamination found in these ID plasmas, points to such magnetic configurations as being good candidates for the NBI experimental program in TJ-II.

Summary: The behavior of four coffee (Coffea canephora cv. Robusta) clones was evaluated in this work to define the conditions that would allw somatic embryogenesis to be induced at different seasons of the year. The objective was to have an adaptive methodology for in vitro propagation of these four coffee clones that were selected for their agronomic characteristics. The use of 2,4-dichlorophenoxyacetic acid and Picloram in the culture medium at concentrations between 2.07 and 4.14 μM resulted in high-frequency somatic embryogenesis when leaves were collected between April and June for genotype C-R, and between April and July for M-229. Callus from 28 to 35d of induction showed better results throughout the whole regeneration process, particularly in liquid medium. There was a clear difference in the behavior of the clones evaluated.

Aqueous extracts of medicinal plants (Mikania laevigataand Campomanesia xanthocarpa) were screened for the presence of mutagenic activity in the Salmonella/microsome assay. The extracts of Campomanesia xanthocarpa showed frameshift (TA97a strain) signs of mutagenic activity without exogenous metabolism (S9 fraction). The infusions of Mikania laevigata, negative for mutagenic activity, showed high percentages of inhibition of mutagenesis induced by mutagens 2AF (2‐aminofluorene), in the presence of exogenous metabolism (S9 fraction), for frameshift (TA98) and base pair substitution (TA100) lesions. In addition, these inhibitions were observed against mutagen SAZ (sodium azide) in assays with the TA100 strain, without exogenous metabolism (S9 fraction). A synergistic effect was also observed in frameshift mutagenic events, with direct action in the presence of 4NQO (4‐oxide‐1‐nitroquinoline) and a tendency to a low percentage of action enhancement, in the presence of the 2AF mutagen. The variable responses observed in the extract assays show the potentials for interaction of the different active principles in genetic material. Copyright © 2003 John Wiley & Sons, Ltd.

Aqueous extracts of medicinal plants (Mikania laevigata and Campomanesia xanthocarpa) were screened for the presence of mutagenic activity in the Salmonella/microsome assay. The extracts of Campomanesia xanthocarpa showed frameshift (TA97a strain) signs of mutagenic activity without exogenous metabolism (S9 fraction). The infusions of Mikania laevigata, negative for mutagenic activity, showed high percentages of inhibition of mutagenesis induced by mutagens 2AF (2-aminofluorene), in the presence of exogenous metabolism (S9 fraction), for frameshift (TA98) and base pair substitution (TA100) lesions. In addition, these inhibitions were observed against mutagen SAZ (sodium azide) in assays with the TA100 strain, without exogenous metabolism (S9 fraction). A synergistic effect was also observed in frameshift mutagenic events, with direct action in the presence of 4NQO (4-oxide-1-nitroquinoline) and a tendency to a low percentage of action enhancement, in the presence of the 2AF mutagen. The variable responses observed in the extract assays show the potentials for interaction of the different active principles in genetic material. Copyright © 2003 John Wiley & Sons, Ltd.

Histocytological analysis carried out on leaf explants of Coffea arabicaundergoing somatic embryogenesis revealed that, using a culture method involving a single Gelrite-containing semisolid medium, the entire region surrounding the edge of the plant-derived leaf explants showed the differentiation of organized structures with little or no callusing. Histological examination of embryogenesis without callus formation (direct somatic embryogenesis) revealed that at approximately 1 week after the explant had been placed in culture, the development of the embryo began in the form of a small, isodiametric, densely cytoplasmic cell that underwent a series of organized divisions. In embryogenesis from callus (indirect somatic embryogenesis), however, the embryogenic cell was observed within the first week. Our histological observations indicate that both direct and indirect somatic embryos of coffee that form on explanted leaf segments and callus, respectively, have a unicellular origin.

Embryogenic cell suspension cultures of Coffea arabica cv. Caturra Rojo were treated with salicylic acid (SA). Two concentrations, 10–12and 10–10 M, had a significant effect on the growth rate of the cell cultures when compared to the control, and this effect was concentration-dependent. These two SA concentrations also had a dramatic effect on both the number of somatic embryos and quality, in terms of embryo size and development. In general, the use of SA had a positive effect on cellular growth and somatic embryogenesis, causing a twofold increase in both processes. The increase in the number of somatic embryos could be a reflection of an increase in the number of embryogenic cells induced with SA treatment.

Coffee (Coffea arabica)plants are usually grown in soils containing high levels of organic materials. Under these conditions, aluminum (Al) is toxic because of the acidic nature of the soils. Al is the most abundant metal found in the earth's crust and occurs in a number of different forms in soil. In acid soils, Al toxicity is a global problem that limits crop productivity. A major problem in obtaining cellular lines displaying Al tolerance in culture is the composition of the medium. In the experiments presented here, we modified the composition of the culture medium for aC. arabicacell line to produce Al toxicity. Murashige-Skoog media was used, complete (MS) and half ionic strength (MSHIS), at either pH 5.8 or 4.3. We found that MSHIS and pH 4.3 provided the optimal conditions to obtain Al toxicity as measured by the ability to grow in a range of Al concentrations (25–1,000 µM). The lethal dose (LD50) under these conditions was 25 µM. The concentrations of free Al in the culture medium were corroborated by the fluorescent compound Morin. Al was found to enter the cell after 30 min, and the signal was then retained for up to 2 h.

Hepatitis C virus was the most frequent cause of liver failure requiring liver transplantation in our series. Hepatitis C virus infection has been associated with glomerulonephritis and, more frequently, type I membranoproliferative glomerulonephritis. Renal disease in patients with liver failure is often clinically silent and difficult to diagnose; thus, biopsy is required to establish the diagnosis. Our aim was to study the evolution of six patients diagnosed with membranoproliferative glomerulonephritis some months before liver transplantation.

Between 1987 and 1993, 53 hepatic resections for hepatocellular carcinoma (HCC) were performed in 51 patients with cirrhosis. Limited hepatic resection was performed in 66 per cent of patients. The postoperative mortality rate was 13 per cent. The tumours recurred in 27 patients (53 per cent), and the cumulative recurrence rate at 1 and 4 years was 41 and 89 per cent, respectively. Mean time to recurrence was 11·7 months and the most frequent site was the liver (21 patients). The only significant risk factor for recurrence was symptomatic tumours. The recurrence rate of HCC in patients with cirrhosis with surgical resection alone is high and actuarial survival at 4 years is very low. Other approaches to the treatment of HCC in patients with cirrhosis require consideration.

Abstract. Our objective in this study was to determine the efficacy of 2 grams a day of oral acyclovir administered for 16 weeks after transplantation for the prevention of cytomegalovirus (CMV) infection and disease in CMV‐seropositive liver transplant recipients. Seventy‐three adult liver transplant recipients, seropositive for CMV, were randomized to receive either 2 grams a day of oral acyclovir for 16 weeks after transplantation or no prophylaxis. The incidence of CMV disease was significantly lower in the acyclovir group (5 %) than in the control group (27 %; P< 0.05). By log‐rank analysis, the differences in the probability of presenting CMV disease over the first 16 weeks and over the 1st year were also significant (P< 0.05). We conclude that 2 grams a day of oral acyclovir provides effective prophylaxis against CMV disease in CMV‐seropositive liver transplant recipients.

We have studied the distribution of viral sequences from the 5' noncoding region and from a fragment of the E2/NS2 region of the hepatitis C virus (HCV) genome in samples obtained before and after liver transplantation in two patients with HCV cirrhosis. The population of viral sequences in both regions were established by sequencing cloned PCR products. In both cases, the complexity of the viral quasispecies decreased after transplantation, although the consensus nucleotide and amino acid sequences remained unchanged. It is suggested that both positive and negative selection and random sampling events contribute substantially in shaping the genetic composition of HCV quasispecies and that recurrence of HCV infection may occur under equilibrium conditions.

Summary Several problems regarding the protein acceptor of the oligosaccharide from GEA (glucosylated endogenous acceptor) were investigated in the present work using rat liver microsomal subfractions. It was found that the acceptor molecule is present in rough and smooth liver microsomes. Furthermore both fractions have closely similar specific activities. The problem of whether nascent peptides must be ribosome bound for glycosylation to occur was studied. The results suggests that binding of peptides to ribosomes is not a necessary condition for the transfer of GEA oligosaccharide to protein. The increase in specific activity found after partial release of the microsomal vesicular content suggests that the acceptor protein for GEA is membrane bound. Evidence obtained in attempting to elucidate whether nascent or completed chains are glycosylated favours the later possibility.

Two year old, transformed root cultures of Catharanthus roseus accumulate ajmalicine and catharanthine (0.57 and 0.36 mg g-1 DW, or 7.0 and 3.0 mg l-1, respectively). Changes in the concentration of the medium components, as well as the addition of hydrolytic enzymes and biotic elicitors, were used as strategies to increase these alkaloid yields. Regarding the components of the medium, the results obtained, when sucrose was raised from 3 to 4.5%, are noteworthy. The nitrogen source induced differential responses in the individual alkaloid yields. No net change in the alkaloid content was observed either with changes in the concentration of vitamins or macro-and micronutrients. Though the root culture only shows a limited response to elicitors, Aspergillus treatment and the use of macerozyme increased the accumulation of ajmalicine selectively, while the addition of methyl jasmonate increased the yield of both alkaloids.

Abstract: The aim of this paper was the screening of the variability of growth patterns, biomass and tropane alkaloid production of 500 hairy root lines ofDatura stramonium. Data on the long term stability in alkaloid production of these lines for more than 5 years are also provided. In an effort to obtain high alkaloid-producing root clones, it is demonstrated that systematic selection is necessary. Comparisons are made, mainly concerning alkaloid production and its stability, with normal root cultures initiated from the same mother plants when necessary. Hairy root cultures were found to have a hyoscyamine and scopolamine bioproductivity of 2 orders of magnitude higher than mother plants.

BACKGROUND & AIMS: Treatment of spontaneous bacterial peritonitis currently involves intravenous antibiotic administration. To test the possibility of treating spontaneous bacterial peritonitis with oral antibiotics, oral ofloxacin was compared with intravenous cefotaxime in this infection. METHODS: One hundred twenty-three cirrhotics with uncomplicated spontaneous bacterial peritonitis (no septic shock, grade II-IV hepatic encephalopathy, serum creatinine level of > 3 mg/dL, and gastrointestinal hemorrhage or ileus) were randomly given oral ofloxacin (64 patients) or intravenous cefotaxime (59 patients). RESULTS: Infection resolution rate was 84% in the ofloxacin group and 85% in the cefotaxime group. Peak serum levels and trough serum and ascitic fluid levels of ofloxacin and cefotaxime measured on days 3 (23 patients) and 6 (11 patients) of therapy were greater than the minimal inhibitory concentration of isolated organisms. Hospital survival rate was 81% in each group of patients. Blood urea nitrogen and hepatic encephalopathy at diagnosis were associated with prognosis. None of the 36 nonazotemic patients with community-acquired spontaneous bacterial peritonitis and without hepatic encephalopathy developed complications during hospitalization, and all were alive at time of discharge. CONCLUSIONS: Oral ofloxacin is as effective as intravenous cefotaxime in uncomplicated spontaneous bacterial peritonitis. Nonazotemic cirrhotic patients with uncomplicated community-acquired spontaneous bacterial peritonitis and without hepatic encephalopathy have an excellent prognosis and may be treated with oral ofloxacin without requiring hospitalization. (Gastroenterology 1996 Oct;111(4):1011-7)

BACKGROUND & AIMS: Paracentesis associated with plasma expanders is widely used for the treatment of ascites in cirrhosis. This study investigated the clinical importance of paracentesis-induced- circulatory dysfunction and compared the efficacy of albumin, dextran 70, and polygeline in preventing this complication. METHODS: A total of 289 cirrhotic patients with ascites were randomized to treatment by total paracentesis plus intravenous albumin (97 patients), dextran 70 (93 patients), or polygeline (99 patients). Postparacentesis circulatory dysfunction was defined as an increase in plasma renin activity on the sixth day after paracentesis of more than 50% of the pretreatment value to a level > 4 ng.mL-1.h-1. RESULTS: Postparacentesis circulatory dysfunction occurred more frequently in patients treated with dextran 70 (34.4%; P = 0.018) or polygeline (37.8%; P = 0.004) than in those receiving albumin (18.5%). The plasma expander used and the volume of ascites removed were independent predictors of this complication. Postparacentesis circulatory dysfunction persisted during follow-up and was associated with a shorter time to first readmission (1.3 +/- 0.5 vs. 3.5 +/- 0.8 months, median +/- SEM; P = 0.03) and shorter survival (9.3 +/- 4.2 vs. 16.9 +/- 4.3 months; P = 0.01). Creatinine and sodium levels in serum, and Child- Pugh score at inclusion, and postparacentesis circulatory dysfunction were independent predictors of survival. CONCLUSIONS: Postparacentesis circulatory dysfunction is not spontaneously reversible and is associated with a shorter time to first readmission and shorter survival. Albumin is the best plasma expander to prevent this complication. (Gastroenterology 1996 Oct;111(4):1002-10)

The daily concentrations of nickel in total (ie inhalable) and respirable airborne dust (personal sampling) and in post-shift and pre-shift urine samples were monitored during five consecutive work days in 20 workers exposed to NiO in a workshop manufacturing electrical resistances. The individual daily atmospheric nickel concentrations ranged from 0.5 to 9586 micrograms Ni/m3 (geometric mean 22.9) for total dust and from 0.2 to 332 micrograms Ni/m3 (geometric mean 3.5) for respirable dust. The results of the urinary excretion of nickel suggested that the occupationally-related systemic absorption of nickel strongly differed in one subject (worker E) compared to the other 19 workers. In the latter group the nickel concentration in urine never exceeded 5 micrograms Ni/g creatinine, it did not differ between post-shift and pre-shift samples (geometric means: 1.1 versus 1.2 micrograms Ni/g creatinine), and it was only slightly higher than that measured in a group of 17 non-exposed subjects (mean 0.5 micrograms Ni/g creatinine; range 0.1-1.7); furthermore their nickel elimination in urine did not change during the days off or after two weeks of holiday. In worker E, the nickel concentration ranged from 21 to 101 micrograms Ni/g creatinine in post-shift urine, the next morning (after 16 h) it had dropped on average by 50 per cent, it decreased further during the days off, and amounted still to 4.4 micrograms Ni/g creatinine after two weeks of holiday. These divergent patterns of elimination of nickel in urine are most likely related to differences in the nature of exposure to airborne nickel involving both particle size and bioavailability of nickel. Worker E was exposed to NiO powder of 1-8 microns particle size resulting in nickel levels of the respirable fraction on average about 50 times that measured for the 19 other workers (3 micrograms Ni/m3). Transformation of the initial NiO powder into particles of 150 to 600 microns size and associated changes in physicochemical properties of NiO in the particles of the respirable fraction may explain why the urinary excretion of nickel in the 19 workers is hardly influenced by their occupational exposure to this metal. The pattern of urinary nickel elimination in worker E, however, most likely reflects very recent exposure to NiO, suggesting that the degree of bioavailability of nickel from this particular physicochemical form of NiO powder is much higher than that usually accepted for poorly soluble nickel compounds.

The frequency of hepatitis C virus (HCV) infection in Spain was assessed by means of a recombinant-based immunoassay for serum anti-HCV antibodies. 836 serum samples were tested from 676 patients selected according to their risk of blood-borne viral infections and presence of liver disease. Among patients at high risk of infection (with or without liver disease) anti-HCV antibodies were found in 85% of prospectively followed patients with post-transfusion non-A, non-B hepatitis, 62% of patients with chronic hepatitis or cirrhosis and a history of blood transfusion, 70% of haemophiliacs receiving replacement therapy, 70% of intravenous drug abusers, and 20% of haemodialysis patients. Only 8% of homosexual men infected with human immunodeficiency virus and 6% of female contacts of drug abusers were positive. Among patients with liver disease and no history of parenteral exposure to blood, anti-HCV antibodies were detected in 38% with cryptogenic, alcoholic, or primary biliary cirrhosis and in 44% with chronic active hepatitis. Among healthy subjects without risk factors for hepatitis the overall prevalence of anti-HCV was 1·2%.

The release of alkaloids from root culturesDatura stramoniumandCatharanthus roseusand thiophenes from root cultures ofTagetes patulawas found to increase when the pH of the culture media (ranging from 4.8 to 7.0) was reduced to 3.5. The extent of the effect was different in each type of culture. Increases ranged from 4- to 20-fold, which in some cases accounted for 75% of the total secondary metabolite pool produced per flask. When the release of individual metabolites was measured, even larger increases, were observed (nearly 400-fold for ajmalicine). Increased release of alkaloids fromC. roseusroots were also observed in cultures growing in a 14-L fermentor, when the medium pH was reduced. Reduction of the pH of the media did not affect growth of the root cultures in subsequent subcultures. The importance of this treatment as a stategy to improve the recovery of secondary metabolites from producing cultures is discussed.

We have reported that mid-region fragments of human parathyroid hormone (hPTH), exemplified by hPTH-(28-48), stimulated [3H]thymidine incorporation into DNA and increased the specific activity of the brain-type isoenzyme of creatine kinase (CK) in both skeletal-derived cell cultures (ROS 17/2.8 cells) and immature rat epiphyseal cartilage and diaphyseal bone, without stimulating cyclic AMP synthesis which is a prerequisite for bone resorption. In the present study, substitution of amino acids in hPTH-(28-48), which resulted in increased resistance to proteolysis, produced variants that stimulated skeletal systems at two orders of magnitude lower concentration than the wild-type fragment. We modified hPTH-(28-48) at Leu-37 by replacement with Met, Thr or Val. Under conditions in which 20% of the native hPTH-(28-48) resisted proteolysis by cathepsin D for 6 h, approx. 40% of the L37V mutant and 70% of the L37T mutant remained intact. Substitution of Met for Phe-34 in addition to Thr for Leu-37, or the substitution of Met for Phe-34 alone, produced 100%-resistant fragments. These variants at residue 34 caused maximal stimulation of CK in ROS 17/2.8 cells at 0.24 nM compared with 24 nM for hPTH-(28-48). The double mutant stimulated CK activity significantly in immature rats, at a minimum dose of 12.5 ng/rat, and caused maximal stimulation at 125 ng/rat, a 10-fold lower dose than for hPTH-(28-48). The effect of the double mutant lasted up to 24 h which differs from the stimulation by hPTH-(28-48) in which CK specific activity returns to the control level at 24 h. This same dose also significantly stimulated CK activity in gonadectomized rats. These results show the advantage of using protease-resistant mid-region variants of hPTH-(28-48) to stimulate bone cells, in terms of lower doses and longer duration of effectiveness, both in vitro and in vivo.

Thymine dimers were obtained under ultraviolet irradiation. The major product is a trans-anti dimer linked by a cyciobutane ring. The infrared assignments and the mechanism of formation of this dimer are discussed in terms of an approximate force field and INDO data, respectively.

In vitro cultures of hairy root derived from Catharanthus roseusaccumulate higher levels of indole alkaloids than cell suspension cultures. Hairy roots were interconverted to undifferentiated cells by manipulation of the culture medium. When the concentration of micronutrients in the culture medium was five times that of Phillips and Collins (1979) medium, cell suspensions formed from the hairy roots. The alkaloid content was five times lower in the cell suspensions than in the control, but upon regeneration of the roots the alkaloid content regained its original level. The formation of cell suspensions from hairy roots was also accompanied by a reduction in tryptophan decarboxylase and the strictosidine synthase activity to less than 5% and 30%, respectively. 3-Hydroxymethylglutaryl coenzyme A reductase activity was the same in the cell suspension and in the regenerated line.

Summary: Ten transformed and two non-transformed root lines ofCatharanthus roseus were established. A systematic study of the growth kinetics and alkaloid content was performed over a culture cycle and showed significant differences between transformed and non-transformed cultures. Mean doubling times for transformed and normal root lines were 2.8 and 19.5 days, respectively. Alkaloid content in hairy roots was from two- to threefold higher than in the non-transformed tissues. The established transformed root lines produced a wide variety of indole alkaloids as can be observed from their complex thin layer chromatography patterns. A large quantity of serpentine was determined in two of the transformed root cultures. Alkaloid content, both quantitatively and qualitatively, has been stable in the hairy root cultures for more than 2 yr of subculturing.

Neuronal perikarya were isolated from rat cerebral cortex at different stages of postnatal development. Membranes sedimenting at 100000 g were obtained from these neurons to study several glycosyltransferases of the dolichol pathway. Enzyme activities from stages before and during synapse formation were compared (days 5 and 15 respectively). Dolichyl diphosphate (Dol-P-P) N-acetylglucosamine, dolichyl phosphate mannose and dolichyl phosphate glucose synthases and the enzymes catalysing Dol-P-P-GlcNAc2Man9Glc3 formation were higher at day 15 of postnatal development. The glycosyl transfer of the latter compound to endogenous protein(s) as well as to a dinitrophenyl-heptapeptide was also measured. The activity was higher at day 15. Furthermore, the activity of dolichyl phosphate mannose synthase was also measured during the time when the number of synapses ceased to increase (day 36) and in the adult stage. The activity of dolichyl phosphate mannose synthase was higher at day 36 than at day 15, and declined in the adult stage. From these results it may be concluded that there is an increase in the glycosylation of asparagine-type glycoproteins during synapse formation in the neurons of the cerebral cortex.

Under extensive ranching conditions in Bolivia where vampire bat transmitted rabies infection occurs in unvaccinated calves, vaccination with modified live virus (MLV-ERA) vaccine protected cattle for three and four years after a single primary vaccination.

In this work, a new nonstationary multiple‐point geostatistical methodology called vector field‐based simulation is presented. This method generates multiple realizations of the phenomena being modeled, whose spatial continuity is described by a training image. It can be applied in reservoir characterization and can be used to study the behavior of hydrogeological systems. The main novelty of this work is that nonstationarity is addressed through a vector field inferred from the training image. This field represents the directions in which the image develops and controls the multiple‐point statistics methods (MPS) simulation. Additionally, our simulation is adapted to support hard data conditioning. The method is tested, and the realizations exhibit a similar morphology as the training image but with substantial variability. Furthermore, in the results it can be seen that the connectivity presented in the training image is preserved. A vector field extracted from the training image is used to control a nonstationary simulationVECSIM preserves the connectivity presented in the training imageVECSIM is applied to tree‐like images presented in alluvial fans, deltas, and submarine fans

A new bis(carbene) ligand architecture has been developed and was evaluated in the Suzuki−Miyaura cross-coupling reaction of various aryl halides with phenylboronic acid. Several new bis(carbene) ligands were tested in different carbene:Pd ratios. Pd(OAc)2 and Pd2(dba)3 were compared for efficiency as a Pd source. It was found that the Pd(OAc)2/bis(carbene) system formed a catalyst for the activation of chlorobenzene.

We have analyzed the population of hepatitis C virus (HCV) sequences in paired liver and serum samples from four patients with chronic hepatitis C. Sequences from three different biopsy specimens from a liver explant from one patient were compared with each other and with the circulating sequences. Our results demonstrate that the circulating quasispecies does not necessarily reflect the viral population replicating in the liver and that this is not due to a macroscopic anatomic compartmentalization of HCV replication. This finding has important implications for the pathogenesis and natural history of chronic HCV infection.