Hemophagocytic lymphohistiocytosis in a pancreas-kidney transplant recipient: response to dexamethasone and cyclosporine.

We describe a severe case of hemophagocytic lymphohistiocytosis (HLH), secondary to a candida glabrata retroperitoneal abscess in a 41-year-old simultaneous pancreas-kidney transplantation (SPKT) recipient. Despite percutaneous abscess drainage and antifungal therapy, general status deteriorated with persistent fever, severe pancytopenia and liver dysfunction. Presence of hypertriglyceridemia, very high serum levels of ferritin and hemophagocytosis in a bone-marrow aspirate gave the diagnosis of HLH. Of note, change from tacrolimus to cyclosporine together with dexamethasone produced rapid response with status improvement. We concluded that HLH, a rare but often fatal condition characterized by excessive activation of lymphocytes and macrophages, is a diagnostic and therapeutic challenge in solid-organ transplanted patients and must be suspected in the presence of fever, blood cytopenia and liver dysfunction. Specific antiinfectious therapy together with cyclosporine and dexamethasone may be a therapeutic approach.

[A successful pregnancy in female after simultaneous kidney-pancreas transplantation]. / Embarazo a término en receptora de trasplante simultáneo de riñón y páncreas.

The effects of pregnancy on kidney transplant recipients have been widely described, although its impact on the mother, the fetus and the graft is still debated. Experience in simultaneous kidney-pancreas transplantation is limited, with few reported cases, which increases uncertainty about guidelines to follow in this situation. We describe a case of successful pregnancy in a 35 year-old patient who underwent simultaneous pancreas-kidney transplantation 34 months before delivery. After modifications in immunosuppressive therapy (with tacrolimus and mycophenolate, the latter being switched to azathioprine), pregnancy evolved favourably. Delivery was by caesarean section due to fetal distress at 38 weeks of gestational age. Five months after delivery the child shows normal development while both pancreas and kidney grafts show normal function.

Embarazo a término en receptora de trasplante simultáneo de riñón y páncreas / Full term pregnancy after simultaneous kidney and pancreas transplantation

Los efectos del embarazo en receptoras de un trasplante renal han sido ampliamente descritos aunque su impacto sobre el injerto, el receptor o en el feto es aún motivo de debate. La experiencia en el trasplante simultáneo de riñón y páncreas es escasa debido al limitado número de casos publicados lo que incrementa la incertidumbre sobre la pauta a seguir en esta situación. Se describe un caso de embarazo a término en una receptora de trasplante simultáneo de riñón y páncreas de 35 años de edad a los 34 meses del implante. Tras modificaciones en el tratamiento inmunosupresor, el embarazo evoluciona favorablemente dando a luz la paciente, mediante cesárea de urgencia por sufrimiento fetal, a las semanas 38 de gestación. A los 5 meses del parto ambos injertos funcionan normalmente siendo el desarrollo del niño totalmente normal (AU)

The effects of pregnancy on kidney transplant recipients have been widely described, although its impact on the mother, the fetus and the graft is still debated. Experience in simultaneous kidney-pancreas transplantation is limited, with few reported cases, which increases uncertainty about guidelines to follow in this situation. We describe a case of successful pregnancy in a 35year-old patient who underwent simultaneous pancreas-kidney transplantation 34 months before delivery. After modifications in immunosuppressive therapy (with tacrolimus and mycophenolate, the latter being switched to azathioprine), pregnancy evolved favourably. Delivery was by caesarean section due to fetal distress at 38 weeks of gestational age. Five months after delivery the child shows normal development while both pancreas and kidney grafts show normal function (AU)

Drosophila melanogaster Thor and response to Candida albicans infection.

We used Drosophila melanogaster macrophage-like Schneider 2 (S2) cells as a model to study cell-mediated innate immunity against infection by the opportunistic fungal pathogen Candida albicans. Transcriptional profiling of S2 cells coincubated with C. albicans cells revealed up-regulation of several genes. One of the most highly up-regulated genes during this interaction is the D. melanogaster translational regulator 4E-BP encoded by the Thor gene. Analysis of Drosophila 4E-BP(null) mutant survival upon infection with C. albicans showed that 4E-BP plays an important role in host defense, suggesting a role for translational control in the D. melanogaster response to C. albicans infection.

[Improved short-term cardiovascular profile after simultaneous pancreas-kidney transplantation]. / Evolución a corto plazo de los factores de riesgo cardiovascular tras el trasplante reno-pancreático.

The prognosis of type 1 diabetes mellitus (T1DM) patients with chronic renal failure (CRF) improves after simultaneous pancreas-kidney (SPK) transplantation. In order to evaluate the changes in cardio-vascular risk (CVR) factors after SKP, we studied nine recipients before and 6 months after SPK. There were five females and four males, with a mean age of 37 +/- 8 years, duration of diabetes of 24 +/- 5 years, three of them before starting dialysis, and six on dialysis (hemodialysis = 5; peritoneal dialysis = 1). Before SPK, all patients received anti-hypertensive therapy (1-4 drugs; mean 2.2 +/- 0.9) and eight received statins. At 6 months after SPK, all patients were under triple immunosuppressive therapy (steroids + tacrolimus + MMF) without statins. They had normal renal function (Plasma Creatinine = 1.2 +/- 0.3 mg/dl) and pancreatic endocrine function (glycemia = 80 +/- 8 mg/dl). HbA1c decreased significantly (8.4 +/- 1.2 vs 4.7 +/- 0.6%; p < 0.007) with a value > 7% in seven patients before SPK and in none 6 months after SKP transplantation (p < 0.001). Although Body Mass Index increased (23 +/- 2 vs 25 +/- 3 kg/m2; p < 0.05), plasma triglycerides decreased (130 +/- 51 vs 88 +/- 33 mg/dl; p < 0.05), and total cholesterol, LDL-cholesterol and HDL-cholesterol were similar. Systolic and diastolic blood pressure (BP) decreased (156 +/- 7 vs 133 +/- 15; p < 0.01 and 96 +/- 7 vs 79 +/- 9; p < 0.007) with only two patients on anti-hypertensive therapy (1 drug). Likewise, before transplantation all patients were hypertensive (six grade 1 and three grade 2) while this was observed in only two at the end of follow-up (both grade 1) (p < 0.001). In conclusion, SPK transplantation with good renal and pancreatic function is associated with a short-term improvement in CVR profile.

Evolución a corto plazo de los factores de riesgo cardiovascular tras el trasplante reno-pancreático / Improved short-term cardiovascular profile after simultaneous pancreas-kidney transplantation

El pronóstico del paciente con diabetes mellitus tipo 1 (DMT1) e insuficienciarenal crónica (IRC) mejora tras el trasplante reno-pancreático (TRP). Con el fin deevaluar los cambios en los factores de riesgo cardio-vascular (RCV) se analizaronnueve pacientes que recibieron un TRP, antes (pre-TRP) y a los 6 meses de seguimiento(pos-TRP). Tres pacientes no habían iniciado diálisis, cinco estaban enhemodiálisis, y uno en diálisis peritoneal. Pre-TRP todos los pacientes recibían hipotensores(nº de fármacos = 2,2 ± 0,9; rango 1-4) y ocho de ellos estatinas. Eltratamiento inmunosupresor consistió en Tacrolimus, Micofenolato Mofetil y esteroides.Pos-TRP todos mantenían función renal y pancreática normales (creatininaplasmática 1,2 ± 0,3 mg/dl; glucemia = 80 ± 8 mg/dl) sin necesidad de estatinas.La HbA1c descendió de forma significativa (8,4 ± 1,2 vs 4,7 ± 0,6%; p <0,007), presentando un valor superior al 7%, siete pacientes pre-TRP frente a ningunopos-TRP (p < 0,001). Aunque el Índice de Masa Corporal aumentó (23 ± 2vs 25 ± 3 kg/m2; p < 0,05), los triglicéridos descendieron (130 ± 51 vs 88 ± 33mg/dl; p < 0,05), y el colesterol total, HDL-colesterol, LDL-colesterol fueron similares.La tensión arterial sistólica (TAs) y diastólica (TAd) descendió de forma significativa(156 ± 7 vs 133 ± 15; p < 0,01 y 96 ± 7 vs 79 ± 9; p < 0,007 respectivamente)y sólo dos pacientes recibían hipotensores pos-TRP (1 fármaco). Enconclusión, estos datos sugieren que a corto plazo el TRP mejora algunos de losfactores de RCV lo que pudiera traducirse en una optimización del pronóstico amás largo plazo

The prognosis of type 1 diabetes mellitus (T1DM) patients with chronic renalfailure (CRF) improves after simultaneous pancreas-kidney (SPK) transplantation.In order to evaluate the changes in cardio-vascular risk (CVR) factors after SKP,we studied nine recipients before and 6 months after SPK. There were five femalesand four males, with a mean age of 37 ± 8 years, duration of diabetes of 24± 5 years, three of them before starting dialysis, and six on dialysis (hemodialysis= 5; peritoneal dialysis = 1). Before SPK, all patients received anti-hypertensivetherapy (1-4 drugs; mean 2.2 ± 0.9) and eight received statins. At 6 months afterSPK, all patients were under triple immunosuppressive therapy (steroids + tacrolimus+ MMF) without statins. They had normal renal function (Plasma Creatinine=1.2 ± 0.3 mg/dl) and pancreatic endocrine function (glycemia = 80 ± 8 mg/dl).HbA1c decreased significantly (8.4 ± 1.2 vs 4.7 ± 0.6%; p 7% in seven patients before SPK and in none 6 months after SKP transplantation(p < 0.001). Although Body Mass Index increased (23 ± 2 vs 25 ± 3 kg/m2;p < 0.05), plasma triglycerides decreased (130 ± 51 vs 88 ± 33 mg/dl; p < 0.05),and total cholesterol, LDL-cholesterol and HDL-cholesterol were similar. Systolicand diastolic blood pressure (BP) decreased (156 ± 7 vs 133 ± 15; p < 0.01 and96 ± 7 vs 79 ± 9; p < 0.007) with only two patients on anti-hypertensive therapy(1 drug). Likewise, before transplantation all patients were hypertensive (six grade1 and three grade 2) while this was observed in only two at the end of followup(both grade 1) (p < 0.001). In conclusion, SPK transplantation with good renaland pancreatic function is associated with a short-term improvement in CVR profile

CaALK8, an alkane assimilating cytochrome P450, confers multidrug resistance when expressed in a hypersensitive strain of Candida albicans.

We report the isolation of a novel C. albicans gene designated CaALK8, by its ability to complement drug hypersensitivity of a pdr5 (ABC: ATP-binding cassette drug extrusion pump) null mutant of S. cerevisiae (JG436). CaALK8 in JG436 conferred resistance to drugs such as cycloheximide (CYH), fluconazole (FCZ), O-phenanthroline (PHE) and 4-nitroquinoline oxide (NQO). The gene was so designated because its sequence was identical to a partial sequence entry named as ALK8 in the Candida database (http://alces.med.umn.edu/candida.html). CaALK8 encodes for a putative 515 amino acid protein highly homologous to alkane-inducible cytochromes P450 (CYP52 gene family) of C. maltosa and C. tropicalis. The ability of CaALK8 to confer drug resistance was also established by its expression in another drug-hypersensitive strain of S. cerevisiae (AD 1234568), which was deleted in seven ABC efflux pumps. The homozygous disruption of CaALK8 in a wild-type C. albicans strain (CAI4) did not result in altered drug susceptibilities. The overexpression of CaALK8 in CAI4 resulted in only FCZ resistance. However, a distinct MDR phenotype was evident when CaALK8 was overexpressed in a drug-hypersensitive C. albicans strain disrupted in both CDR1 and CDR2 (ABC drug extrusion pumps of C. albicans). Alk8p, similar to other Alk proteins from C. maltosa and C. tropicalis, could hydroxylate alkanes and fatty acids. In this study we demonstrate that several drugs could compete with the hydroxylation activity by directly interacting with CaAlk8p. Taken together, our results suggest that a member of the CYP52 gene family could mediate MDR in C. albicans, although it does not seem to be involved in the development of azole resistance in clinical isolates. The nucleotide sequence reported in this paper has been submitted to GenBank under Accession No. Y14766.

Multiple Yap1p-binding sites mediate induction of the yeast major facilitator FLR1 gene in response to drugs, oxidants, and alkylating agents.

The bZip transcription factor Yap1p plays an important role in oxidative stress response and multidrug resistance in Saccharomyces cerevisiae. We have previously demonstrated that the FLR1 gene, encoding a multidrug transporter of the major facilitator superfamily, is a transcriptional target of Yap1p. The FLR1 promoter contains three potential Yap1p response elements (YREs) at positions -148 (YRE1), -167 (YRE2), and -364 (YRE3). To address the function of these YREs, the three sites have been individually mutated and tested in transactivation assays. Our results show that (i) each of the three YREs is functional and important for the optimal transactivation of FLR1 by Yap1p and that (ii) the three YREs are not functionally equivalent, mutation of YRE3 being the most deleterious, followed by YRE2 and YRE1. Simultaneous mutation of the three YREs abolished transactivation of the promoter by Yap1p, demonstrating that the three sites are essential for the regulation of FLR1 by Yap1p. Gel retardation assays confirmed that Yap1p differentially binds to the three YREs (YRE3 > YRE2 > YRE1). We show that the transcription of FLR1 is induced upon cell treatment with the oxidizing agents diamide, diethylmaleate, hydrogen peroxide, and tert-butyl hydroperoxide, the antimitotic drug benomyl, and the alkylating agent methylmethane sulfonate and that this induction is mediated by Yap1p through the three YREs. Finally, we show that FLR1 overexpression confers resistance to diamide, diethylmaleate, and menadione but hypersensitivity to H(2)O(2), demonstrating that the Flr1p transporter participates in Yap1p-mediated oxidative stress response in S. cerevisiae.

Molecular cloning of the CRM1 gene from Candida albicans.

In a screen for Candida albicans genes capable of supressing a ste20Delta mutation in Saccharomyces cerevisiae, a homologue of the exportin-encoding gene CRM1 was isolated. The CaCRM1 gene codes for a protein of 1079 amino acids with a predicted molecular weight of 124 029 and isoelectric point of 5.04. Crm1p from C. albicans displays significant amino acid sequence homology with Crm1p from Saccharomyces cerevisiae (65% identity, 74% similarity), Schizosaccharomyces pombe (55% identity, 66% similarity), Caenorhabditis elegans (45% identity, 57% similarity), and Homo sapiens (48% identity, 59% similarity). Interestingly, CaCRM1 encodes a threonine rather than a cysteine at position 533 in the conserved central region, suggesting that CaCrm1p is leptomycin B-insensitive, like S. cerevisiae Crm1p. CaCRM1 on a high copy vector can complement a thermosensitive allele of CRM1 (xpo1-1) in S. cerevisiae, showing that CaCrm1p and S. cerevisiae Crm1p are functionally conserved. Southern blot analysis suggests that CaCRM1 is present at a single locus within the C. albicans genome. The nucleotide sequence of the CaCRM1 gene has been deposited at GenBank under Accession No. AF178855.

The bZip transcription factor Cap1p is involved in multidrug resistance and oxidative stress response in Candida albicans.

Candida albicans is an opportunistic pathogenic yeast which frequently develops resistance to the antifungal agent fluconazole (FCZ) in patients undergoing long-term therapy. FCZ-resistant strains often display a reduced intracellular FCZ accumulation which correlates with the overexpression of the ATP-binding cassette transporters CDR1 and CDR2 or the major facilitator (MF) MDR1. We have recently cloned a C. albicans gene, named CAP1, which codes for a bZip transcription factor of the AP-1 family homologous to the Yap1 protein involved in multidrug resistance and response to oxidative stress in Saccharomyces cerevisiae. CAP1 was found to confer FCZ resistance in S. cerevisiae by transcriptionally activating FLR1, a gene coding for an MF homologous to the C. albicans MDR1 gene product (A.-M. Alarco, I. Balan, D. Talibi, N. Mainville, and M. Raymond, J. Biol. Chem. 272:19304-19313, 1997). To study the role of CAP1 in C. albicans, we constructed a CAI4-derived mutant strain carrying a homozygous deletion of the CAP1 gene (CJD21). We found that deletion of CAP1 did not affect the susceptibility of CJD21 cells to FCZ, cerulenin, brefeldin A, and diamide but caused hypersensitivity to cadmium, 4-nitroquinoline N-oxide, 1,10-phenanthroline, and hydrogen peroxide, an effect which was reverted by reintroduction of the CAP1 gene in these cells. Introduction of a hyperactive truncated allele of CAP1 (CAP1-TR) in CJD21 resulted in resistance of the cells to all of the above compounds except hydrogen peroxide. The hyperresistant phenotype displayed by the CJD21 CAP1-TR transformants was found to correlate with the overexpression of a number of potential CAP1 transcriptional targets such as MDR1, CaYCF1, CaGLR1, and CaTRR1. Taken together, our results demonstrate that CAP1 is involved in multidrug resistance and oxidative stress response in C. albicans. Finally, disruption of CAP1 in strain FR2, selected in vitro for FCZ resistance and constitutively overexpressing MDR1, did not suppress but rather increased the levels of MDR1 expression, demonstrating that CAP1 acts as a negative transcriptional regulator of the MDR1 gene in FR2 and is not responsible for MDR1 overexpression in this strain.

The terminal O-acetyltransferase involved in vindoline biosynthesis defines a new class of proteins responsible for coenzyme A-dependent acyl transfer.

The gene encoding acetyl CoA:deacetylvindoline 4-O-acetyltransferase (DAT) (EC 2.3.1.107) which catalyzes the last step in vindoline biosynthesis was isolated and characterized. The genomic clone encoded a 50 kDa polypeptide containing the sequences of nine tryptic fragments derived from the purified DAT heterodimer. However, cleavage of DAT protein to yield a heterodimer appears to be an artifact of the protein purification procedure, since the size of the protein (50 kDa) cross-reacting with anti-DAT antibody in seedlings and in leaves of various ages also corresponds to the size of the active recombinant enzyme. Studies with the intact plant and with developing seedlings showed that induction of DAT mRNA, protein accumulation and enzyme activity occurred preferentially in vindoline producing tissues such as leaves and cotyledons of light-treated etiolated seedlings. The ORF of DAT showed significant sequence identity to 19 other plant genes, whose biochemical functions were mostly unknown. The Mr of approximately 50 kDa, a HXXXDG triad, and a DFGWGKP consensus sequence are highly conserved among the 20 plant genes and these criteria may be useful to identify this type of acyltransferase. The involvement of some of these genes in epicuticular wax biosynthesis, fruit-ripening and in benzoyltransfer reactions indicates that the plant kingdom contains a superfamily of multifunctional acyltransferases which operate by a reaction mechanism related to the ancient chloramphenicol O-acetyltransferase and dihydrolipoyl acetyltransferase class of enzymes.

A Ste6p/P-glycoprotein homologue from the asexual yeast Candida albicans transports the a-factor mating pheromone in Saccharomyces cerevisiae.

In Saccharomyces cerevisiae MATa cells, export of the a-factor mating pheromone is mediated by Ste6p, a member of the ATP-binding cassette (ABC) superfamily of transporters and a close homologue of mammalian multidrug transporter P-glycoproteins (Pgps). We have used functional complementation of a ste6delta mutation to isolate a gene encoding an ABC transporter capable of a-factor export from the pathogenic yeast, Candida albicans. This gene codes for a 1323-amino acid protein with an intramolecular duplicated structure, each repeated half containing six potential hydrophobic transmembrane segments and a hydrophilic domain with consensus sequences for an ATP-binding fold. The predicted protein displays significant sequence similarity to S. cerevisiae Ste6p and mammalian Pgps. The gene has been named HST6, for homologue of STE6. A high degree of structural conservation between the STE6 and the HST6 loci with respect to DNA sequence, physical linkage and transcriptional arrangement indicates that HST6 is the C. albicans orthologue of the S. cerevisiae STE6 gene. We show that the HST6 gene is transcribed in a haploid-specific manner in S. cerevisiae, consistent with the presence in its promoter of a consensus sequence for Mata1p-Matalpha2p binding known to mediate the repression of haploid-specific genes in S. cerevisiae diploid cells. In C. albicans, HST6 is expressed constitutively at high levels in the different cell types analysed (yeast, hyphae, white and opaque), demonstrating that HST6 transcription is not repressed in this diploid yeast, unlike in diploid S. cerevisiae, and suggesting a basic biological function for the Hst6p transporter in C. albicans. The strong similarity between Hst6p and the multidrug transporter Pgps also raises the possibility that Hst6p could be involved in resistance to antifungal drugs in C. albicans.

The Candida albicans CDR3 gene codes for an opaque-phase ABC transporter.

We report the cloning and functional analysis of a third member of the CDR gene family in Candida albicans, named CDR3. This gene codes for an ABC (ATP-binding cassette) transporter of 1,501 amino acids highly homologous to Cdr1p and Cdr2p (56 and 55% amino acid sequence identity, respectively), two transporters involved in fluconazole resistance in C. albicans. The predicted structure of Cdr3p is typical of the PDR/CDR family, with two similar halves, each comprising an N-terminal hydrophilic domain with consensus sequences for ATP binding and a C-terminal hydrophobic domain with six predicted transmembrane segments. Northern analysis showed that CDR3 expression is regulated in a cell-type-specific manner, with low levels of CDR3 mRNA in CAI4 yeast and hyphal cells, high levels in WO-1 opaque cells, and undetectable levels in WO-1 white cells. Disruption of both alleles of CDR3 in CAI4 resulted in no obvious changes in cell morphology, growth rate, or susceptibility to fluconazole. Overexpression of Cdr3p in C. albicans did not result in increased cellular resistance to fluconazole, cycloheximide, and 4-nitroquinoline-N-oxide, which are known substrates for different transporters of the PDR/CDR family. These results indicate that despite a high degree of sequence conservation with C. albicans Cdr1p and Cdr2p, Cdr3p does not appear to be involved in drug resistance, at least to the compounds tested which include the clinically relevant antifungal agent fluconazole. Rather, the high level of Cdr3p expression in WO-1 opaque cells suggests an opaque-phase-associated biological function which remains to be identified.

Molecular cloning and characterization of desacetoxyvindoline-4-hydroxylase, a 2-oxoglutarate dependent-dioxygenase involved in the biosynthesis of vindoline in Catharanthus roseus (L.) G. Don.

A 2-oxoglutarate-dependent dioxygenase (EC 1.14.11.11) which catalyzes the 4-hydroxylation of desacetoxyvindoline was purified to homogeneity. Three oligopeptides isolated from a tryptic digest of the purified protein were microsequenced and one oligopeptide showed significant homology to hyoscyamine 6 beta-hydroxylase from Hyoscyamus niger. A 36-mer degenerate oligonucleotide based on this peptide sequence was used to screen a Catharanthus roseus cDNA library and three clones, cD4H-1 to -3, were isolated. Although none of the three clones were full-length, the open reading frame on each clone encoded a putative protein containing the sequence of all three peptides. Primer extension analysis suggested that cD4H-3, the longest cDNA clone, was missing 156 bp at the 5' end of the clone and sequencing of the genomic clone, gD4H-8, confirmed these results. Southern blot analysis suggested that d4h is present as a single-copy gene in C. roseus which is a diploid plant, and the significant differences in the sequence of the 3'-UTR between cD4H-1 and -3 suggest that they represent dimorphic alleles of the same hydroxylase. The identity of the clone was further confirmed when extracts of transformed Escherichia coli expressed D4H enzyme activity. The D4H clone encoded a putative protein of 401 amino acids with a calculated molecular mass of 45.5 kDa and the amino acid sequence showed a high degree of similarity with those of a growing family of 2-oxoglutarate-dependent dioxygenases of plant and fungal origin. The similarity was not restricted to the dioxygenase protein sequences but was also extended to the gene structure and organization since the 205 and 1720 bp introns of d4h were inserted around the same highly conserved amino acid consensus sequences as those for e8 protein, hyoscyamine-6 beta-hydroxylase and ethylene-forming enzyme. These results provide further support that a common ancestral gene is responsible for the appearance of this family of dioxygenases. Hydroxylase assays and RNA blot hybridization studies showed that enzyme activity followed closely the levels of d4h transcripts, occurring predominantly in young leaves and in much lower levels in stems and fruits. In contrast, etiolated seedlings which contained considerable levels of d4h transcripts had almost undetectable hydroxylase activity, whereas exposure of seedlings to light resulted in a rapid increase of enzyme activity without a significant further increase in d4h transcripts over those detected in dark-grown seedlings. These results suggest that the activating effect of light may occur at a point downstream of transcription which remains to be elucidated.

AP1-mediated multidrug resistance in Saccharomyces cerevisiae requires FLR1 encoding a transporter of the major facilitator superfamily.

We have isolated a Candida albicans gene that confers resistance to the azole derivative fluconazole (FCZ) when overexpressed in Saccharomyces cerevisiae. This gene encodes a protein highly homologous to S. cerevisiae yAP-1, a bZip transcription factor known to mediate cellular resistance to toxicants such as cycloheximide (CYH), 4-nitroquinoline N-oxide (4-NQO), cadmium, and hydrogen peroxide. The gene was named CAP1, for C. albicans AP-1. Cap1 and yAP-1 are functional homologues, since CAP1 expression in a yap1 mutant strain partially restores the ability of the cells to grow on toxic concentrations of cadmium or hydrogen peroxide. We have found that the expression of YBR008c, an open reading frame identified in the yeast genome sequencing project and predicted to code for a multidrug transporter of the major facilitator superfamily, is dramatically induced in S. cerevisiae cells overexpressing CAP1. Overexpression of either CAP1 or YAP1 in a wild-type strain results in resistance to FCZ, CYH, and 4-NQO, whereas such resistance is completely abrogated (FCZ and CYH) or strongly reduced (4-NQO) in a ybr008c deletion mutant, demonstrating that YBR008c is involved in YAP1- and CAP1-mediated multidrug resistance. YBR008c has been renamed FLR1, for fluconazole resistance 1. The expression of an FLR1-lacZ reporter construct is strongly induced by the overexpression of either CAP1 or YAP1, indicating that the FLR1 gene is transcriptionally regulated by the Cap1 and yAP-1 proteins. Taken collectively, our results demonstrate that FLR1 represents a new YAP1-controlled multidrug resistance molecular determinant in S. cerevisiae. A similar detoxification pathway is also likely to operate in C. albicans.

[The bioavailability of drugs administered via a minimal jejunostomy catheter. A clinico-experimental study]. / Biodisponibilidad de los fármacos administrados por yeyunostomía mínima a catéter. Estudio clínico-experimental.

For the evaluation of the bioavailability of drugs administered through a minimal jejunostomy catheter (MJC) postoperatively, ampicillin and metronidazol were administered via this route. The study with ampicillin consisted of a first cross-over experimental trial, in which six dogs were used, and a second based on the experience with four human volunteers. As a measure of the absorption of the drug, the serum levels of the lower plasma area are monitored. The statistical analysis was done by means of logarithmic transformation of the areas, and two-way analysis of variance. The posterior distribution of the relative bioavailability of the drug was obtained by applying a bayesian method. The results showed an important decrease of the ampicillin absorption, while the expected bioavailability when administered through MJC was 0.24, and the 95% interval (0.19, 0.30). The expected bioavailability of metronidazol when administered through MJC was 0.84, and the 95% interval (0.66, 1.07). This new route of drug administration in patients who undergo abdominal surgery, is shown to be of great importance from a clinical point of view, and should be kept in mind.

[Gastric cavernous hemangioma as a cause of upper digestive hemorrhage]. / Hemangioma cavernoso gástrico como causa de hemorragia digestiva alta.

Upper digestive bleeding caused by an isolated gastric hemangioma is a rather rare occurrence, even in cases of Osler-Weber-Rendu syndrome. The case reported here, which brings to 40 the number reported in the world literature, is that of a 68-year-old patient who presented with upper digestive bleeding. Endoscopy led us to suspect a hemangioma due to the abnormally large lesion, a suspicion that was confirmed preoperatively through arteriography, which detected a hypervascular mass of 6 x 4 cm dependent on the gastroduodenal artery. This finding was in turn confirmed by the surgical intervention. Diagnostic difficulties based on barium studies, endoscopy and surgical exploration have meant that preoperative diagnosis has been rare in the cases published to date. We consider that a more liberal use of arteriography could reverse this tendency, as indeed our case has shown. Furthermore, we feel that arteriography is indicated in cases of upper digestive bleeding of obscure origin, which might be due to small angiomas that may be overlooked in other diagnostic tests.

[Volvulus of the transverse colon: a rare cause of intestinal obstruction]. / Vólvulo de colon transverso: una causa poco frecuente de obstrucción intestinal.

Volvulus of the transverse colon is rare, given its short and fixed mesentery and the normal fixation of the hepatic and splenic flexures of the colon. The case reported herein brings the total of reported cases to 72. Various predisposing factors have been identified, most notably congenital abnormalities, physiologic disturbances and mechanical obstruction; in our case these three factors were present. The possible role of colonoscopy in diagnosis and/or therapy is unclear. In our patient, colonoscopy proved to be of no use for diagnosis or treatment.

Auxins induce tryptophan decarboxylase activity in radicles of catharanthus seedlings.

Germinating seedlings of Catharanthus roseus produce monoterpenoid indole alkaloids as a result of a transient increase of tryptophan decarboxylase (TDC) activity. The influence of auxins on this transient rise of TDC activity was studied. External application of indolebutyric acid or 2,4-dichlorophenoxyacetic acid at a concentration of 20 to 40 mum enhanced and prolonged the rise in TDC activity in developing seedlings. Auxin treatment also influenced the morphology of the seedlings; it induced a shortening and thickening of the hypocotyl and the radicle and promoted the initiation of lateral roots in the radicle. During development, the radicles of auxin-treated seedlings displayed a gradual increase in TDC activity that was absent in the radicles of untreated controls. Examination of immunoblots revealed anti-TDC reactive proteins in extracts from radicles of auxin-treated seedlings, but none in extracts from radicles of control seedlings. In contrast, TDC activity and immunoreactive protein levels in the aerial parts of controls and auxin-treated seedlings were comparable. Our results indicate that externally applied auxins induce both abnormal development and TDC activity in the radicles of Catharanthus seedlings. Although auxins slightly delayed the light-mediated induction of the cotyledon-specific last step in vindoline biosynthesis (i.e. acetylcoenzyme A: deacetylvindolin-O-acetyltransferase activity), seedlings still synthesized vindoline, one of the major alkaloid end products.

Intercostal pedicled flap in esophageal atresia.

Since 1974 we have used an intercostal pedicled flap (IPF) between the esophageal anastomosis and the sutured trachea in a single case of recurrent tracheoesophageal fistula (TEF) and in four cases of primary repair of esophageal atresia (EA) and TEF in which the distance between both ends was greater than 2.5 cm and with a certain degree of tension in the anastomotic line. Furthermore, in the last two cases reported in this article, we have been able to use the IFP in an extrapleural approach in a way not previously reported. The short-term and long-term follow-ups have been excellent without any complications relating to the esophagus itself or to the pedicle flap of intercostal muscle. The method is considered particularly useful in recurrent fistulas.