Biochemical and regulatory properties of a respiratory island encoded by a conjugative plasmid in the extreme thermophile Thermus thermophilus

In the present paper, we summarize the current knowledge on the first step of the denitrification pathway in the ancestral extreme thermophilic bacterium Thermus thermophilus. In this organism, nitrate respiration is performed by a mobilizable respiratory island that encodes a new type of respiratory NADH dehydrogenase as electron donor, a tetrameric membrane nitrate reductase as final electron acceptor, two nitrate/nitrite transporters and the transcription factors required for their expression in response to nitrate and anoxia.

Scedosporium apiospermum: changing clinical spectrum of a therapy-refractory opportunist*

Current knowledge on the opportunist Scedosporium apiospermum (teleomorph: Pseudallescheria boydii), generated over a period of more than 120 years, is reviewed. The natural environmental habitat of the fungus is unknown; nutrient-rich, brackish waters like river estuaria have been suggested. The fungus is strongly promoted by agricultural and particularly by industrial pollution.

HIV-associated lymphoma successfully treated with peripheral blood stem cell transplantation

OBJECTIVE

To evaluate feasibility, safety, and efficacy of peripheral blood stem cell collection (PBSCC) and autologous stem cell transplantation (ASCT), to treat patients diagnosed of high-risk or relapsed HIV-associated lymphoma (HIV+ Ly), responding to highly active antiretroviral therapy (HAART).

METHODS

Prospective and multicentric study in patients with high-risk or relapsed chemosensitive HIV+ Ly, candidate for consolidation with ASCT. Eligibility criteria were similar to those of HIV- lymphoma. HAART was aimed to be maintained during the procedure.

RESULTS

Fourteen patients were admitted. Adequate PBSCC was obtained from all patients (median CD34+ cells was 4.7 x 10(6)/kg). Three patients died before ASCT; two had disease progression and one died from VHC-liver failure. Eleven transplanted patients showed neutrophil engraftment after a median time of 16 days (range, 9-33 days), and nine patients showed platelet engraftment after a median time of 20 days (range, 11-36 days). CD4+ cell counts and HIV viral load (VL) were appropriately preserved along the procedure. No patients died from treatment-related complications. One patient died from lymphoma progression (day +19), and another died in complete remission (CR) with undetectable VL, 15 months after transplant, due to infection. One patient relapsed at 32 months after ASCT. The remaining eight patients are alive in CR with an event-free survival of 65% and a median follow-up of 30 months after ASCT (range, 7-36 months).

CONCLUSIONS

These results show that feasibility, safety, and efficacy of PBSCC and ASCT in HIV+ Ly patients responding to HAART are similar to those observed in the HIV- lymphoma setting.

Lipid disorders in antiretroviral-naive patients treated with lopinavir/ritonavir-based HAART: frequency, characterization and risk factors

OBJECTIVES

The aim of this study was to evaluate the frequency, characteristics and risk factors of lipid changes associated with lopinavir/ritonavir treatment in antiretroviral-naive patients.

METHODS

A prospective cohort of 107 antiretroviral-naive HIV-infected patients was followed for 12 months after starting lopinavir/ritonavir-based highly active antiretroviral therapy.

RESULTS

At 12 months, percentages of patients with hypercholesterolaemia and hypertriglyceridaemia were 17.4% and 40%, respectively. Mean increases in total cholesterol and triglycerides were 40.7 and 73.3 mg/dL. There was a significant increase in both low-density and high-density (HDL) cholesterol, and no increase in the total cholesterol/HDL ratio (from 4.16 at baseline to 4.49 after 12 months). Baseline cholesterol > 200 mg/dL and triglycerides > 150 mg/dL were independent risk factors for dyslipidaemia, while hepatitis C coinfection appeared to be protective.

CONCLUSIONS

Patients with elevated lipid values at baseline have the greatest risk of developing hypercholesterolaemia and hypertriglyceridaemia after starting lopinavir/ritonavir. Antiretroviral-naive patients coinfected with hepatitis C have a low risk of developing hyperlipidaemia after starting lopinavir/ritonavir.

Clinical and MRI outcome after autologous hematopoietic stem cell transplantation in MS

The authors report the outcome of 14 patients with severe multiple sclerosis treated with autologous hematopoietic stem cell transplantation (AHSCT) after a median follow-up period of 3 years. The 3-year actuarial probability of progression-free survival was 85.7% and that of disease activity-free survival was 46.4%. On MRI, no T1-enhanced lesions were detected after AHSCT. The mean change in T2 lesion volume from baseline to the third year was -20.2% and that of the corpus callosum area was -12.7%; 50% of this reduction was seen during the first year.

Recomendaciones de GESIDA/Plan Nacional sobre el Sida respecto al tratamiento antirretroviral en pacientes adultos infectados por el VIH (octubre 2004)

OBJECTIVE

This consensus document is an update of antiretroviral therapy (ART) recommendations for adult patients infected with the human immunodeficiency virus (HIV).

METHODS

To formulate these recommendations, a panel composed of members of the Grupo de Estudio de Sida (GESIDA; AIDS Study Group) and the Plan Nacional sobre el Sida (PNS; Spanish AIDS Plan) reviewed the advances in current understanding of the pathophysiology of HIV, the safety and efficacy findings from clinical trials, and the results from cohort and pharmacokinetic studies published in biomedical journals or presented at scientific meetings over the last years. Three levels of evidence were defined according to the source of the data: randomized studies (level A), cohort or case-control studies (level B), and expert opinion (level C). The decision to recommend, consider or not recommend ART was established in each of these situations.

RESULTS

ART consisting of at least three drugs is currently the initial treatment of choice for chronic HIV infection. These regimens should include 2 NRTI + 1 NNRTI or 2 NRTI + 1 PI. Initiation of ART is recommended in patients with symptomatic HIV infection. In asymptomatic patients, initiation of ART is recommended on the basis of CD4+ lymphocyte counts per L and plasma viral load, as follows: 1) Therapy should be started in patients with CD4+ counts of < 200 cells/microL; 2) Therapy should be started in most patients with CD4+ counts of 200-350 cells/microL, although it can be delayed when CD4+ count persists at around 350 cells/microL and viral load is low; and 3) Initiation of therapy can be delayed in patients with CD4+ counts of > 350 cells/microL. The initial objective of ART is to achieve an undetectable viral load. Adherence to therapy plays an essential role in maintaining the antiviral response. Because of the development of cross resistance, therapeutic options are limited when ART fails. Genotype studies are useful in these cases. Toxicity is a limiting factor in the use of ART, although the benefits outweigh the risks. In addition, the criteria for the use of ART are discussed in situations of acute infection, pregnancy, and post-exposure prophylaxis, and in the management of co-infection of HIV with HCV or HBV.

CONCLUSIONS

CD4+ lymphocyte count is the most important reference factor for initiating ART in asymptomatic patients. The large number of available drugs, the increased sensitivity of tests to monitor viral load, and the possibility to determine viral resistance is leading to a more individualized approach to therapy.

A New Type of NADH Dehydrogenase Specific for Nitrate Respiration in the Extreme Thermophile Thermus thermophilus

A four-gene operon (nrcDEFN) was identified within a conjugative element that allows Thermus thermophilus to use nitrate as an electron acceptor. Three of them encode homologues to components of bacterial respiratory chains: NrcD to ferredoxins; NrcF to iron-sulfur-containing subunits of succinate-quinone oxidoreductase (SQR); and NrcN to type-II NADH dehydrogenases (NDHs). The fourth gene, nrcE, encodes a membrane protein with no homologues in the protein data bank. Nitrate reduction with NADH was catalyzed by membrane fractions of the wild type strain, but was severely impaired in nrc::kat insertion mutants. A fusion to a thermophilic reporter gene was used for the first time in Thermus spp. to show that expression of nrc required the presence of nitrate and anoxic conditions. Therefore, a role for the nrc products as a new type of membrane NDH specific for nitrate respiration was deduced. Consistent with this, nrc::kat mutants grew more slowly than the wild type strain under anaerobic conditions, but not in the presence of oxygen. The oligomeric structure of this Nrc-NDH was deduced from the analysis of insertion mutants and a two-hybrid bacterial system. Attachment to the membrane of NrcD, NrcF, and NrcN was dependent on NrcE, whose cytoplasmic C terminus interacts with the three proteins. Interactions were also detected between NrcN and NrcF. Inactivation of nrcF produced solubilization of NrcN, but not of NrcD. These data lead us to conclude that the Nrc proteins form a distinct third type of bacterial respiratory NDH.

Evaluation of bone marrow and blood cultures for the recovery of mycobacteria in the diagnosis of disseminated mycobacterial infections

This study evaluated the validity of bone marrow (BM) and blood specimens for the diagnosis of disseminated mycobacterial infections (DMIs). From 1990 to February 1997, all specimens were processed with the lysis-centrifugation procedure; thereafter (until December 2001), they were processed with the BACTEC Myco/F Lytic system. Twenty-three paired BM-blood specimens with mycobacteria in at least one specimen were studied from 23 patients. The strains isolated were 14 Mycobacterium avium complex (MAC) and nine M. tuberculosis complex (MTBC). Blood specimens had a statistically significant greater sensitivity for the isolation of MAC than BM (100% vs. 57.1%, respectively), whereas sensitivity for the isolation of MTBC was equal for the two specimen types (66.7%). Although not statistically significant, the times required to detect mycobacteria from blood specimens were lower than those from BM in the MycoF/Lytic system. Overall, blood cultures represented a more sensitive and less invasive alternative to BM cultures for the diagnosis of disseminated mycobacteriosis caused by MAC, especially when the MycoF/Lytic system was used, but provided no advantage for the diagnosis of DMI caused by MTBC.

Parapharyngeal angiolipoma causing obstructive sleep apnoea syndrome

Obstructive sleep apnoea syndrome (OSAS) is the cessation of airflow with the continuance of respiratory effort during sleep. OSAS associated with a neck mass is extremely rare. Angiolipoma is a rare, benign, fatty tumour composed of mature lipocytes and multiple areas containing angiomatous elements. The treatment for an angiolipoma is surgical excision. We report the case of a 47-year-old male who presented with a history of loud snoring associated with sleep apnoea. A polysomnographic study demonstrated an apnoea-hypopnoea index of 72/h. CT showed a 3.5 x 3 x 8 cm3 hypoattenuated mass of fat density in the left parapharyngeal space causing an impression on the nasopharynx and oropharynx with a peripheral hyperintense area. A cervical transparotid surgical approach was used. A histological study led to the definitive diagnosis of angiolipomal without evidence of malignancy. After surgery, the snoring disappeared and the patient remained tumour-free after 54 months of follow-up. This is the first case in the literature of a patient with nocturnal polysomnographic-documented OSAS caused by a left parapharyngeal angiolipoma.

Prevention of opportunistic infections in adult and adolescent patients with HIV infection. GESIDA/National AIDS Plan guidelines, 2004 [correction]

OBJECTIVE

To provide an update of guidelines from the Spanish AIDS Study Group (GESIDA) and the National AIDS Plan (PNS) committee on the prevention of opportunistic infections in adult and adolescent HIV-infected patients.

METHODS

These consensus recommendations have been produced by a group of experts from GESIDA and/or the PNS after reviewing the earlier document and the scientific advances in this field in the last years. The system used by the Infectious Diseases Society of America and the United States Public Health Service has been used to classify the strength and quality of the data.

RESULTS

This document provides a detailed review of the measures for the prevention of infections caused by viruses, bacteria, fungi and parasites in the context of HIV infection. Recommendations are given for preventing exposure and for primary and secondary prophylaxis for each group of pathogens. In addition, criteria are established for the withdrawal of prophylaxis in patients who respond well to highly active antiretroviral therapy (HAART).

CONCLUSIONS

HAART is the best strategy for the prevention of opportunistic infections in HIV-positive patients. Nevertheless, prophylaxis is still necessary in countries with limited economic resources, in highly immunodepressed patients until HAART achieves beneficial effects, in patients who refuse to take or who cannot take HAART, in those in whom HAART is not effective, and in the small group of infected patients with inadequate recovery of CD4+ T lymphocyte counts despite good inhibition of HIV replication.

Budd-Chiari syndrome caused by membranous obstruction of the inferior vena cava associated with coeliac disease

Ten cases of Budd-Chiari syndrome associated with coeliac disease have been reported in the literature, most of them in North African subjects. Supporting this association, we report a new case in a young Spanish Caucasian man in whom the cause of the syndrome was the membranous obstruction of the inferior vena cava, an infrequent cause of Budd-Chiari syndrome in Western countries. A percutaneous balloon angioplasty was performed, with satisfactory outcome.

Vanguardia en el estudio del córtex auditivo. demostración de su activación mediante resonancia magnética funcional

PURPOSE

The purpose of this preliminary study has been to demonstrate and investigate the activation patterns of the primary auditory cortex (Heschl's gyrus = HG) using functional magnetic resonance imaging (fMRI).

MATERIAL AND METHODS

A 2500 Hz tone stimulus was delivered monoaurally to the right and left ear of 15 normal-hearing right-handed volunteers in 20-second on-off cycles. FMRI data were obtained using a 1.5-Tesla scanner and processed with SPM2.

RESULTS

Activated pixels were identified in the transverse temporal gyrus (Heschl's gyrus) of both hemispheres in response to pure tone stimuli using cross-correlation analysis (P < 0.001). Bilateral hemispheric activation was observed in all subjects and there was a trend towards contralateral HG activation to the stimulated ear.

CONCLUSION

These results demonstrate directly that fMRI is a new and useful imaging technique to study the complex auditory cortex and it will have potential clinical applications in the next future.

Consensus conference on chronic viral hepatitis and HIV infection: updated Spanish recommendations

Chronic hepatitis B and C represent a leading cause of morbidity and mortality among human immunodeficiency virus (HIV)-infected patients worldwide. New treatment options against both hepatitis B (HBV) and C (HCV) viruses have prompted us to update previous recommendations for the management of coinfected individuals. Fifteen topics (nine related to HCV, five to HBV and one to both viruses) were selected for this purpose. A panel of Spanish experts in the field was invited to review these areas and propose specific recommendations, which were scored according to the Infectious Disease Society of America (IDSA) grading system. These guidelines represent a comprehensive and updated overview on the management of hepatitis B and C in HIV-infected patients.

Incidence and predictors of severe liver fibrosis in human immunodeficiency virus-infected patients with chronic hepatitis C: a European collaborative study

A study was performed in 10 European health care centers in which 914 patients coinfected with hepatitis C virus (HCV) and human immunodeficiency virus (HIV) who had elevated serum alanine aminotransferase (ALT) levels underwent liver biopsy during the period of 1992 through 2002. Overall, the METAVIR liver fibrosis stage was F0 in 10% of patients, F1 in 33%, F2 in 22%, F3 in 22%, and F4 in 13%. Predictors of severe liver fibrosis (METAVIR stage, F3 or F4) in multivariate analysis were age of >35 years (odds ratio [OR], 2.95; 95% confidence interval [CI], 2.08-4.18), alcohol consumption of >50 g/day (OR, 1.61; 95% CI, 1.1-2.35), and CD4+ T cell count of <500 cells/mm3 (OR, 1.43; 95% CI, 1.03-1.98). Forty-six percent of patients aged >40 years had severe liver fibrosis, compared with 15% of subjects aged <30 years. The use of antiretroviral therapy was not associated with the severity of liver fibrosis. In summary, severe liver fibrosis is frequently found in HCV-HIV-coinfected patients with elevated serum ALT levels, and its severity increases significantly with age. The rate of complications due to end-stage liver disease will inevitably increase in this population, for whom anti-HCV therapy should be considered a priority.

HLA antigens and anti-neutrophil cytoplasmic antibodies (ANCA) in inflammatory bowel disease

HYPOTHESIS AND OBJECTIVES

the hypothesis of this study is that genes involved in the regulation of the immune system, expressed by HLA antigens and anti-neutrophil cytoplasmic antibodies (ANCA), could be determinants of disease susceptibility and behavior in inflammatory bowel disease (IBD).

MATERIAL AND METHOD

seventy patients with a diagnosis of inflammatory bowel disease, 46 with ulcerative colitis and 24 with Crohn"s disease were included. HLA class I (A and B) and II (DR) antigens were studied by serological techniques. Detection of ANCA was carried out in all patients by an indirect immunofluorescence method. The relative frequencies of HLA antigens were compared with a control group made up of 156 blood donors. The control group for the ANCA study was made up of 100 individuals.

RESULTS

we found a significant increased frequency of HLA-DR2 in patients with ulcerative colitis. No significant differences were found between patients with Crohn"s disease and controls regarding HLA typing. We detected a significant increase of HLA-DR3 in extensive forms of ulcerative colitis. Detection of ANCA was positive in 46% of the patients with ulcerative colitis and in 12% of the patients with Crohn"s disease (p <0.05). We observed an increased frequency of ANCA in patients with UC and HLA-DR2 (p = 0.15).

CONCLUSIONS

the association found between HLA-DR3 and extensive forms of ulcerative colitis provides evidence of genetic heterogeneity. The relationship between ANCA and HLA phenotype (although not significant) supports this concept.

[Defining AIDS terminology. A practical approach]

Since the appearance of AIDS, the study of this disease has generated a large amount of information and an extensive related vocabulary comprised of new terms or terms borrowed from other scientific fields. The urgent need to provide names for newly described phenomena and concepts in this field has resulted in the application of terms that are not always appropriate from the linguistic and scientific points of view. We discuss the difficulties in attempting to create adequate AIDS terminology in the Spanish language, considering both the general problems involved in building any scientific vocabulary and the specific problems inherent to this activity in a field whose defining illness has important social connotations. The pressure exerted by the predominance of the English language in reporting scientific knowledge is considered, and the inappropriate words most often found in a review of current literature are examined. Finally, attending to the two most important criteria for the creation of new scientific terms, accuracy and linguistic correction, we propose some well thought-out alternatives that conform to the essence of the Spanish language.

Clinical course and prognostic factors of progressive multifocal leukoencephalopathy in patients treated with highly active antiretroviral therapy

We analyzed survival rates, neurologic function, and prognostic factors for 118 consecutive patients with acquired immunodeficiency syndrome-associated progressive multifocal leukoencephalopathy (PML) treated with highly active antiretroviral therapy (HAART) in 11 hospitals throughout Spain. Seventy-five patients (63.6%) remained alive for a median of 114 weeks (2.2 years) after diagnosis of PML. Neurologic function of the survivors was categorized as cure or improvement in 33, stabilization or worsening in 40, and unknown in 2. The baseline CD4+ cell count was the only variable found with prognostic significance. The odds ratio of death was 2.71 (95% confidence interval, 1.19-6.15) for patients with CD4+ cell counts of <100 cells/microL, compared with patients who had CD4+ cell counts of > or =100 cells/microL. One-third of patients with PML died despite receipt of HAART; neurologic function improved in approximately one-half of the survivors. A CD4+ cell count of <100 cells/microL was associated with higher mortality.

[Endoscopic treatment of pancreatitis and its complications]

OBJECTIVES

To study the long- and short-term safety and efficacy of endoscopic treatment of pancreatitis and its complications in our environment.

PATIENTS AND METHODS

We performed a retrospective analysis of 43 patients with chronic pancreatitis, acute pancreatitis complicated with pseudocyst, and pancreatic fistula diagnosed by endoscopic retrograde cholangiopancreatography who were suitable for endoscopic treatment.

RESULTS

Endoscopic treatment was attempted in 35 patients. The indication for treatment was pain in 17 patients (48.5%), jaundice in 7 (20%), pseudocyst in 10 (28.5%) and suspected external fistula in 1 (3%). The technique was successfully performed in 28 (80%). Of the patients with pain, pancreatic prosthesis was inserted in 13 and extracorporeal lithotripsy was applied in 6. Sixty-five percent of the patients improved. Of the 7 patients with jaundice, all had secondary stenosis of the biliary tract. Treatment was applied in 2, who showed partial improvement. Of the 15 patients with pseudocyst, endoscopic treatment was indicated in 10; the technique was successfully performed in 8 and complete resolution was achieved in 7 (87.5%). The patient with external fistula was treated with transpapillary prosthesis and complete resolution of disruption of Wirsung's duct was achieved. Overall improvement in successfully treated patients was: complete in 19 (68%), partial in 3 (18%), no improvement in 4 (14%) and 2 patients were lost to treatment. There were 4 short-term complications. There were 4 deaths and one was related to the technique.

CONCLUSIONS

Endoscopic treatment of chronic pain in chronic pancreatitis, pseudocysts and fistulas was effective in our environment with a low rate of complications.

[Endoscopic treatment combined with extracorporeal shock wave lithotripsy of difficult bile duct stones]

OBJECTIVES

The aim of this study was to determine the safety and effectiveness of extracorporeal shock wave lithotripsy (ESWL) in difficult bile duct stones resistant to endoscopic extraction.

PATIENTS AND METHOD

From January 1997 to February 2002, combined treatment with endoscopy and ESWL was used in 19 patients who had undergone unsuccessful endoscopic bile duct stone extraction after sphincterotomy. The procedure was carried out using analgesic and sedative drugs or deep sedation, prophylactic antibiotic therapy, and monitoring of vital signs. Bile duct stone localization was performed by contrast injection through nasobiliary drainage and fluoroscopy. After each ESWL session, lavage was performed through drainage and stone fragments were extracted endoscopically.

RESULTS

The 19 patients presented high surgical risk due to advanced aged and/or concomitant diseases. All presented jaundice and pain and nine (47.3%) presented associated cholangitis. Thirty ESWL sessions were performed (1.57 sessions per patient), with a mean of 2,120 shock waves per session. In 16 of the 19 patients (84.2%), combined treatment with ESWL and subsequent instrumental endoscopic extraction achieved complete clearance of the biliary tract. The treatment failed in 3 patients who were referred for surgical treatment. No early or late complications were observed, except in one patient who presented a self-limiting febrile syndrome.

CONCLUSIONS

Therapeutic endoscopy combined with ESWL is safe and effective in patients with difficult bile duct stones. It represents a therapeutic alternative in patients at high surgical risk.

Resistance mutations in HIV-infected patients experiencing early failure with nelfinavir-containing triple combinations

BACKGROUND

The purpose of our study was to assess the presence of nelfinavir (NFV)-associated resistance mutations at the time of early virological failure in subjects receiving NFV as part of a first protease inhibitor (PI)-based triple regimen.

MATERIAL/METHODS

Subjects failing their first PI-based NFV-containing triple regimen were identified in six Spanish hospitals. HIV genotyping was carried out in plasma samples collected at the time of the first viral rebound.

RESULTS

Upon initiation of NFV-based therapy, 19 of the 30 subjects (63%) were naïve; 11 (37%) had been exposed to nucleoside analogues. Median HIV-RNA at the time of viral rebound was 4, 180 copies/ml. PCR-amplified products were obtained in 22 subjects (73%). These products were sequenced and primary PI resistance mutations were recognized in 6 patients (27%). All six individuals harbored the D30N mutation, and none presented the L90M mutation. Other PI resistance mutations were present in 5 subjects (at codons 36, 63, 71, 77, 82 and/or 88). Secondary PI resistance mutations were present in another 9 subjects. By contrast, mutations conferring resistance to reverse transcriptase inhibitors were present in 50% of the patients, and the M184V substitution was the most frequently seen.

CONCLUSIONS

Nearly 75% of patients failing their first PI-based triple regimen containing NFV do not harbor PI resistance mutations. The D30N substitution, rather than L90M, is the most frequently recognized, which does not challenge the efficacy of further rescue interventions with other PIs. This observation supports the use of nelfinavir as first protease inhibitor.

JC virus load in progressive multifocal leukoencephalopathy: analysis of the correlation between the viral burden in cerebrospinal fluid, patient survival, and the volume of neurological lesions

JC virus (JCV) is the causative agent of progressive multifocal leukoencephalopathy (PML), a demyelinating central nervous system infection that mainly affects patients with acquired immunodeficiency syndrome. The diagnostic value of the detection of JCV DNA in cerebrospinal fluid (CSF) has been proved. A correlation between the JCV burden in CSF and the PML prognosis has been proposed. To our knowledge, the present study is the first to examine JCV burden in CSF in relation to the magnitude of neurological damage. An in-house quantitative polymerase chain reaction assay was used for measurement of the JCV burden in CSF samples from 12 patients with PML. A wide variation in JCV load (6.4 log) was found among the patient CSF samples, a finding that makes JCV load measurements worthwhile. Virus load values of >4.68 log were associated with shorter patient survival time. No correlation was found between the virus load values and the global volume of brain tissue damaged. Our data suggest that factors other than the volume of neurological lesions influence the shedding of JCV in the CSF.