Changes in protein synthesis and acid tolerance in Clostridium perfringens type A in response to acid shock

The induction of acid-shock proteins and the degree of acid resistance conferred on Clostridium perfringens by acid shock, and the kinetics of this resistance were determined. A sublethal acid shock at pH 4.5 for 20 min increased the acid tolerance of cells at least fifteenfold. The acquired tolerance was maintained for 3 h after acid treatment. The response of the microorganism to acid shock was also examined by analysis of pulse-labeled proteins. Five acid-shock proteins (molecular weights 120, 84, 58, 45 and 17 kDa) were identified by polyacrylamide gel electrophoresis.

Compression of the ulnar nerve in Guyon's canal by uremic tumoral calcinosis

We describe the case of a 70-year-old woman with chronic renal failure on haemodialysis presenting with an ulnar nerve compression in Guyon's canal secondary to uremic tumoral calcinosis. Excision of calcium deposits and external neurolysis of the ulnar nerve were successfully performed. Simultaneously, the hyperphosphatemia and hypercalcemia were corrected. The pathogenesis of this condition is different from primary tumoral calcinosis. Clinical and radiological features and therapy are discussed. Uremic tumoral calcinosis is an unusual etiology of ulnar nerve compression in Guyon's canal not previously reported in dialysis patients.

Involvement of Fcgamma receptor IIIA genotypes in susceptibility to rheumatoid arthritis

OBJECTIVE

To investigate a possible association of Fcgamma receptor IIIA (FcgammaRIIIA) gene polymorphism at position 158 with susceptibility to, and the outcome of, rheumatoid arthritis (RA).

METHODS

One hundred seventeen RA patients and 142 unrelated healthy control subjects from the same geographic area were studied. Genotyping for FcgammaRIIIA-158V/F was performed by a method based on polymerase chain reaction (PCR) and restriction fragment length polymorphism analysis using amplification-created restriction sites. HLA-DRB1 typing by PCR-sequence-specific oligonucleotide hybridization (reverse hybridization) was also performed.

RESULTS

Allele and genotype distributions in healthy controls were similar to those reported in other populations. The overall distribution of genotypes in the patients was significantly different from that in the controls (P = 0.023, by chi-square test from 3 x 2 contingency table). An overrepresentation of the FcgammaRIIIA-158FF genotype in the patients was observed (for 158FF versus non-158FF P = 0.01, odds ratio [OR] 1.98, 95% confidence interval [95% CI] 1.16-3.4). However, the FcgammaRIIIA-158VF genotype was increased in controls (for 158VF versus non-158VF P = 0.021, OR 0.54, 95% CI 0.32-0.92). No associations were found with any of a series of clinical parameters. Analysis of FcgammaRIIIA-158FF along with shared epitope showed that the presence of both factors increased the susceptibility to RA (P = 0.0009, OR 3.6, 95% CI 1.63-8.01); however, they probably do not interact to produce this effect.

CONCLUSION

These results indicate that the FcgammaRIIIA-158 genotypes confer differential susceptibility to RA in our study population. Further studies to elucidate the role of this polymorphism in the pathogenesis of RA and other autoimmune diseases are warranted.

[Meningoencephalitis caused by Herpesviridae family virus in Cuba. 1996-1998]

Herpesvirus isolation from cerebrospinal fluid (CSF) has proven not to be very useful because of its low sensitivity; that is the reason why PCR has considerably improved the diagnosis of several viral infections of the central nervous system. We studied, by means of PCR, 253 CSF received in our laboratory from 1996 to 1998, which had a suspected diagnosis of herpesviral-associated neurologic disease (encephalitits or meningoencephalitis). Of these, 182 were from HIV seropositive patients and the other 71 were from HIV seronegative. The percentage of all positive cases was 22.5% in AIDS patients and CMV was the virus most frequently detected (13.7%). We detected a percentage of 29.5 of positive cases in immunocompetent individuals, being HSV the virus most frequently found. Other herpesviruses (varicella-zoster virus, Epstein-Barr virus, human herpesvirus 6) were also detected in some cases in both groups. Finally, we obtained clinical data from all positive patients and established a relationship with PCR results.

Is 1-week treatment for peptic ulcer healing sufficient and safe?

OBJECTIVE

To confirm whether 1-week anti-Helicobacter therapy to achieve ulcer healing is sufficient and safe.

METHODS

We retrospectively analyzed patients with peptic ulcer who were infected with Helicobacter pylori and treated with 3 different 7-day regimens, according to predefined protocols in 3 different centers in the same geographical area (Aragón, Spain). Three combinations commonly described in the literature were used: a) omeprazole (40 mg/24 h), tetracycline hydrochloride (2 g/24 h), colloidal bismuth subcitrate (480 mg/24 h) and metronidazole (750 mg/24 h) (OBTM, n = 105); b) omeprazole (40 mg/24 h), clarithromycin (1.5 g/24 h) and amoxicillin (3 g/24 h) (O40C1.5A3, n = 13); and c) omeprazole (40 mg/24 h), clarithromycin (1 g/24 h) and amoxicillin (2 g/24 h) (O40C1A2, n = 4). In all patients the diagnosis of peptic ulcer disease was confirmed endoscopically, and H. pylori infection was verified with urease testing and histological analysis. After treatment ended, no other antacids were allowed until after endoscopic examination to check eradication and ulcer healing.

RESULTS

122 patients were included (107 with duodenal ulcer, 12 with gastric ulcer and 3 with both). Compliance was good and side effects infrequent and mild. Eradication rates were 88.5% (93/105) in the OBTM group, 100% (13/13) with O40C1.5A3, and 75% (3/4) with O40C1A2. Healing was achieved in 98.16% (107/109) of the patients in whom the bacterial infection was eradicated, and in 23.07% (3/13) of those in whom it was not (p < 0.0001). No patient had any complications during the period without treatment.

CONCLUSIONS

1-week eradication therapy with previously described combinations commonly used in clinical practice achieves high ulcer healing rates with no complications in the period without antacid treatment. We consider that it is not necessary, at least in most patients, to prolong antacid therapy.

The procurement team as a factor of bone allograft contamination

We studied the effect of the procurement team on the risk of contamination in 270 large bone allografts retrieved from 53 non-living donors under strictly aseptic conditions.The overall contamination rate was 8.1%. When the procurement team was constituted by three or less members the contamination rate was 5.6%, while if there were four or more members the rate was 12.9%; this difference was significant in the statistical analysis.We conclude that a procurement team constituted by three or less trained members is a determinant factor in decreasing the bacterial contamination rate of bone allografts.

Determination of six metals in galician red wines (in northwestern Spain) by capillary electrophoresis

A simple technique is described for the routine simultaneous capillary electrophoretic determination of 6 cations in wine. Separation was achieved on a fused silica capillary column with a UV-Cat-1, alpha-hydroxysobutyric acid and 18-crown-6-ether buffer at pH 4.5 and indirect UV detection at 214 nm. The content of magnesium, sodium, potassium, calcium, manganese, and lithium was determined. The method is quantitative, with recoveries in the 92-102% range, and linear over more than one order of magnitude. The precision is better than 2.5-3.4%. The method is sensible, with detection limits between 0.01 and 0.06 mg/L. Twenty-five red wines with a Certified Brand of Origin from Galicia (north-western Spain) were analyzed by the proposed method. Various wines showed very similar electrophoretic profiles, but significant quantitative differences were observed.

Genetic analysis of HIV-1 samples from Spain

To characterize the viruses responsible for the HIV-1 epidemic in Spain, we genetically characterized 79 samples obtained from Spanish patients with different risk practices (injecting drug users and male homosexuals) in two regions (Madrid and Navarra). Genetic characterization was carried out by nucleotide sequencing in the C2-V3-C3 region and by phylogenetic analysis. All samples were of subtype B except one that clustered with clade F. Because no segregation of samples was determined according to the risk group of patients nor to their geographic origin, the Spanish samples analyzed constitute a single group of viruses. These data, along with the starlike topology of the phylogenetic tree, support the existence of a single introduction of HIV-1 subtype B in Spain. The mean genetic distance among subtype B sequences was of 13.9%+/-0.06% (range, 5%-25%), suggesting an epidemic of long evolution. Analysis of sequences in relation to isolation dates revealed an increase in the heterogeneity of the nucleotide sequences with time. According to these data, a divergence rate of 0.49%+/-0.11% per year was calculated for the Spanish samples during the period analyzed.

Chromosome 11 abnormalities in myelodysplastic syndromes

Cytogenetic studies were performed in 140 patients with myelodysplastic syndrome (MDS) at diagnosis. Chromosome 11 anomalies were found in 7 cases (5%); 2 of these patients had refractory anemia (RA), 2 had refractory anemia with excess of blasts (RAEB), 1 had RAEB in transformation (RAEB-t), and 2 had chronic myelomonocytic leukemia (CMMoL) according to the French-American-British (FAB) Cooperative Group criteria. The chromosome 11 abnormalities comprised trisomy 11 (2 patients), monosomy 11 (1 patient), del(11)(q23) (2 patients), add(11)(p15) (1 patient), and der(11) t(3;11)(p21;q23) (1 patient). Abnormalities involving band q23 of chromosome 11 occurred in 3 cases and were the most common alteration. However, specific chromosomal alterations were not associated with any FAB classification group. These findings and their implications in the biology of MDS are discussed.

Osteomyelitis of the clavicle. A case report

Osteomyelitis of the clavicle is a rare complication of subclavian vein catheterization. The authors report the case of a patient with osteomyelitis in the right clavicle after subclavian venipuncture.

[Prevalence of antibodies against herpes simplex virus, Epstein-Barr virus and cytomegalovirus in a group of patients after hemodialysis]

Infections from herpes virus play a key role in post-transplantation pathology, so it is indispensable to characterize the group of would-be renal transplant recipients. IgG antibody titers were detected by indirect immunofluorescence to Herpes simplex virus, Epstein Barr virus (EBV) and cytomegalovirus (CMV) in 100 patients treated with hemodialysis in the Nephrology Institute. The prevalence of antibodies to cytomegalovirus and to Herpes simplex and Epstein Barr viruses was 100% and 95% respectively. Average geometric titers (AGT) of antibodies to CMV were significantly higher. There was no correlation between AGT and sex, age, time of disease remission, number of blood transfusions and number of transplants.

Control of filament formation in Candida albicans by polyamine levels

Candida albicans, the most common fungal pathogen, regulates its cellular morphology in response to environmental conditions. The ODC gene, which encodes ornithine decarboxylase, a key enzyme in polyamine biosynthesis, was isolated and disrupted. Homozygous null Candida mutants behaved as polyamine auxotrophs and grew exclusively in the yeast form at low polyamine levels (0.01 mM putrescine) under all conditions tested. An increase in the polyamine concentration (10 mM putrescine) restored the capacity to switch from the yeast to the filamentous form. The strain with a deletion mutation also showed increased sensitivity to salts and calcofluor white. This Candida odc/odc mutant was virulent in a mouse model. The results suggest a model in which polyamine levels exert a pleiotrophic effect on transcriptional activity.

[Herpesvirus detection in immunocompromised patients with meningoencephalitis by the polymerase chain reaction technic]

The multiple polymerase chain reaction technique was used to detect in a single assay tube the presence of herpes simplex virus (HSV), Cytomegalovirus (CMV). Epstein Barr virus (EBV), varicella zoster virus (VZV), and/or human herpes virus-6 (HHV6). 50 cerebrospinal fluids from patients with AIDS and clinically suspected to have meningoencephalitis due to HSV were received and analyzed at the laboratories of Sexually Transmitted Diseases of the Virology Department of the "Pedro Kourí" Tropical Medicine Institute from 1993 to 1996. 4 of them were positive to HSV, 3 to CMV, 2 to VZV, and 1 to HHV6 for a positivity of 20%. The results of the PCR were correlated to the clinical findings presented by the patients at the time of the lumbar puncture. The introduction of this technique in the laboratory allows to have an easy, fast and useful tool for the diagnosis of meningoencephalitis due to herpesvirus.

Heterosexual transmission of HIV-1 is associated with high plasma viral load levels and a positive viral isolation in the infected partner

Risk factors for heterosexual HIV transmission are not fully understood. In fact, a proportion of people with sexual exposure to HIV remain uninfected despite multiple and continuous intercourse with HIV-infected partners. In this work, we have analyzed those virologic parameters potentially involved in the transmission of HIV through heterosexual contact. Thirty-eight couples with continuous unprotected sexual intercourse were included. HIV transmission occurred in 10 of 38 couples. No differences in clinical characteristics, exposure time, sexual practices, CD4 counts, or polymorphism in CCR5 were found between transmitter and nontransmitter groups. In contrast, virologic data were different between both groups; median values of viral load were 21.139 and 5.484 RNA copies/ml of plasma in the transmitter and nontransmitter groups, respectively, and a significant difference was found in mean viral load values (p = .03, Mann-Whitney test). Viral isolation was obtained in 90% of transmitters, but in only 44% of nontransmitter subjects (p = .02, Fisher's exact test). These data show that viral load levels and a positive viral isolation in culture must be considered as risk factors for heterosexual transmission of HIV-1.

[Angioplasty in acute myocardial infarction. Early and late results]

BACKGROUND

The usefulness of angioplasty in the first hours of an acute myocardial infarction is widely demonstrated. However, its long term effects are less well known.

AIM

To report the effects of coronary angioplasty on early and late outcome of patients with acute myocardial infarction.

PATIENTS AND METHODS

A non-randomized, consecutive and retrospective analysis of the hospital and late outcome of 70 patients, aged 35 to 85 years, subjected to coronary angioplasty during an acute myocardial infarction. Patients were followed during 12 to 60 months.

RESULTS

Angioplasty was performed 5.3 +/- 5 hours after the initial symptoms. Anterior descendent artery was occluded in 63% of patients with a 99.5% luminal occlusion and TIMI 0-1 anterograde flow. An angiographic success was achieved in 83% of procedures with a residual stenosis of 32.3%. Recurrent ischemia was observed in 6% of patients, that were treated with a new revascularization procedure. Thirteen percent of patients died, all due to cardiogenic shock. Severe ventricular failure and failure of revascularization influenced mortality. During the first year of follow up there was a 3.3% mortality and 3.3% of patients required a new revascularization procedure. Eighty percent of patients were asymptomatic and event-free.

CONCLUSION

Angioplasty was a useful therapeutic procedure in this group of patients.

Prevalence and characteristics of necrotoxigenic Escherichia coli (NTEC) strains isolated from diarrhoeic dairy calves

Fecal samples from 246, 1-90-days old diarrhoeic dairy calves in 72 herds were screened for the presence of cytotoxic necrotizing factors (CNF)-producing Escherichia coli (NTEC). NTEC were detected by tissue culture assays and PCR in 39 (15.8%) of the diarrheic calves, and the majority of these animals (34 of 39, ca. 87.2%) were infected by NTEC producing CNF2. Calves were grouped according to their age (1-7 days, 8-14 days, 15-21 days, 22-30 days and 31-90 days) and analyses of prevalence were done by the Mantel-Haenzsel chi2-test for trend. A significant age-associated increase in the prevalence of NTEC producing CNF2 (p<0.0001) was found. Eighty-one (8.4%) of the 958 E. coli isolates from the 246 diarrheic calves were positive for CNF in the tissue culture assays. These strains were analyzed by PCR and this technique showed that three (3.7%) strains were CNF1-positive and 75 (92.6%) were CNF2-positive. Moreover, three of the strains positive in the tissue culture assays were negative by PCR. These strains were subsequently assayed in several biological tests (rabbit skin test, mouse intraperitoneal test and mouse footpad test) which showed that they were really NTEC, probably producing CNF2, but with some different properties to classical strains producing CNF2. NTEC strains producing CNF2 belonged to different serogroups (O2, O7, O9, O14, O15, O41, O43, O45, O55, O76, O86, O88, O109, O115, O123, O128, O153 and O159) than strains producing CNF1 (O11 and O32) or PCR-negative strains (O111). Moreover, a strong association between CNF2 and F17 fimbriae was found (78.6% of CNF2-positive strains were F17-positive, whereas only 22.9% of CNF2-negative strains were F17-positive).

[High-frequency jet ventilation with a proximal injector in a case of surgery of the tracheal carina]

A 44-year-old man underwent surgery requiring medial sternotomy of resection of a tracheal carcina tumor. High frequency jet ventilation was used during tumor resection and reconstruction of the carina in order to shorten the time of surgery and to provide a nearly immobile and unobstructed surgical field. The only noteworthy complication was a tendency to respiratory acidosis that resolved without sequelae in the operating room once the trachea was closed. The anesthetic challenges presented by the various techniques used throughout history for such an interesting and complex type of surgery are briefly summarized. We also discuss the role of high frequency jet ventilation on surgery involving the major airways.

Distribution of lithium in different CNS areas and other tissues of adult male and female vizcacha (Lagostomus maximus maximus)

In a previous study (1) we demonstrated that lithium administration (1.0 mmol/kg b.wt., per day for 4 weeks) in intact vizcacha (Lagostomus maximus maximus) leads to significant histological alterations in the kidneys, ovarie and testicles, while these three tissues were not damaged in rats. Male vizcachas died within 4 days when administered LiCl 3 mmol/kg b.wt., while females were not affected. The lithium renal clearance presented no changes in either males or females. The 1.0 mmol/kg b.wt. dose was used in the experiments (2). In this study we examined the distribution of lithium in various tissues of male and female vizcacha (Lagostomus maximus maximus) administered LiCl by injection (1 mmol/kg b.wt.) for one day (Group I) and thirty days (Group II). Blood sample was obtained after 24 hours (Group I) and 30 days (Group II). The tissues investigated were: pituitary, hypothalamus, cerebral cortex, cerebellum, corpus callous, small and large intestine, kidney and suprarenal. The concentration of lithium in tissues and serum was determined by atomic absortion spectrometry (3,4). In Group I a significant lithium concentration increment (mumol/g of tissue) was observed in all the tissues of male vizcachas as compared to female vizcacha. A similar distribution was obtained in animals treated for 30 days. In the pituitary, however this difference between males and females was not significant. The male lithium serum levels were significantly higher than those of female animals. In conclusion, we suggest that the particular structure of the cell membrane (e.g., number and characteristic of sodium channels) of each tissue and/or the intracellular mechanisms of transport, elimination and metabolism might explain the unequal lithium distribution and the difference recovery from the damage produced. The results suggest that the vizcacha could be a useful model for the study of lithium toxicity.

In vitro activities of cephalosporins and quinolones against Escherichia coli strains isolated from diarrheic dairy calves

The in vitro activities of several cephalosporins and quinolones against 195 strains of Escherichia coli isolated from diary calves affected by neonatal diarrhea were determined. One hundred thirty-seven of these strains produced one or more potential virulence factors (F5, F41, F17, cytotoxic necrotizing factor, verotoxin, and the eae gene), but the remaining 58 strains did not produce any of these factors. From 11 to 18% of the E. coli strains were resistant to cephalothin, nalidixic acid, enoxacin, and enrofloxacin. However, cefuroxime, cefotaxime, and cefquinome were highly effective against the E. coli isolates tested. Some significant differences (P < 0.05) in resistance to quinolones between the strains producing potential virulence factors and nonfimbriated, nontoxigenic, eae-negative strains were found. Thus, eae-positive, necrotoxigenic, and verotoxigenic (except for nalidixic acid) E. coli strains were significantly more sensitive to nalidixic acid, enoxacin, and enrofloxacin than nonfimbriated, nontoxigenic, eae-negative strains. Moreover, eae-positive strains were significantly more sensitive to enoxacin and enrofloxacin than F5-positive strains. Thus, the result of this study suggest that the bovine E. coli strains that produce some potential virulence factors are more sensitive to quinolones than those that do not express these factors.

Bone allograft contamination in multiorgan and tissue donors

Multiorgan and tissue donors offer a larger quantity and high quality of bone allograft that cannot be obtained from living donors. The risk of bone contamination must be borne in mind if secondary sterilization is not performed. The bacteriological cultures of 270 bone segments obtained from 53 multiorgan or tissue donors were analysed to study the relationship between previous organ and tissue procurements and bone retrieval contamination. We concluded that no significant differences in bacterial contamination percentage were found for each type of previous organ and tissue procurement, nor in the number of teams per donor.