Targeting bacterial growth in biofilm conditions: rational design of novel inhibitors to mitigate clinical and food contamination using QSAR

Antimicrobial resistance (AMR) is a pressing global issue exacerbated by the abuse of antibiotics and the formation of bacterial biofilms, which cause up to 80% of human bacterial infections. This study presents a computational strategy to address AMR by developing three novel quantitative structure-activity relationship (QSAR) models based on molecular topology to identify potential anti-biofilm and antibacterial agents. The models aim to determine the chemo-topological pattern of Gram (+) antibacterial, Gram (-) antibacterial, and biofilm formation inhibition activity. The models were applied to the virtual screening of a commercial chemical database, resulting in the selection of 58 compounds. Subsequent in vitro assays showed that three of these compounds exhibited the most promising antibacterial activity, with potential applications in enhancing food and medical device safety.

An update on tolvaptan for autosomal dominant polycystic kidney disease

Tolvaptan is an orally active antagonist of vasopressin (antidiuretic hormone [ADH]) V2 receptors. By blocking water reabsorption in kidney collecting ducts, it prompts renal free-water excretion and has been used for the treatment of hyponatremia, both euvolemic due to the syndrome of inappropriate ADH secretion, and hypervolemic due to liver cirrhosis and congestive heart failure. In the past few years, it has been shown that vasopressin and its second messenger cyclic adenosine monophosphate (cAMP) play an important role in the pathogenesis of autosomal dominant polycystic kidney disease (ADPKD). This has been the rationale for the use of tolvaptan to halt the progression of ADPKD, mainly through slowing kidney growth and decline in renal function. Two major randomized clinical trials have demonstrated the benefits of tolvaptan in slowing the progression of ADPKD in terms of kidney growth and decline in renal function at 1 and 3 years (REPRISE and TEMPO). However, the long-term effectiveness of treatment with tolvaptan remains to be determined.

Acute tubulointerstitial nephritis associated with atezolizumab, an anti-programmed death-ligand 1 (pd-l1) antibody therapy

Direct stimulation of the antitumor activity of immune system through checkpoint inhibitors (ICIs) has demonstrated efficacy in the treatment of different cancer types. The activity of these antibodies takes place in the immunological synapse blocking the binding of the negative immunoregulatory proteins, thus leading to the finalization of the immune response. Despite having a favorable toxicity profile, its mechanism of action impedes the negative regulation of the immune activity which can potentially favor autoimmune attacks to normal tissues. Renal toxicity has been described in several ICI but not with atezolizumab, an IgG1 monoclonal antibody targeting PD-L1 (programmed death ligand 1), approved by FDA as a second-line therapy for advanced urothelial carcinoma. Here we present a patient with a single kidney and metastatic renal cell carcinoma treated with atezolizumab and bevacizumab combination, with biopsy-proven acute interstitial nephritis, who had a complete resolution of renal dysfunction after steroid therapy.

Influencia del cruce industrial en los rendimientos productivos y la calidad de la canal de corderos de la raza ovina Segureña

<p>Se han estudiado los rendimientos productivos (peso al nacimiento, peso al sacrificio, y ganancia media diaria), así como los parámetros de calidad de la canal (conformación, engrasamiento, índices de compacidad de la canal y de la pierna, y composición tisular) de corderos provenientes de la raza Segureña y del cruce industrial de ésta con la raza Texel. Se han observado mejoras en los animales cruzados, tanto en la productividad: mayor peso al nacimiento y al sacrificio y una mayor ganancia media diaria de peso, como en la calidad de la canal: mejor conformación, menor engrasamiento, y una mayor composición muscular en contraposición a un menor porcentaje de grasa. Los resultados obtenidos indican que el cruce entre estas dos razas podría ser una herramienta recomendable a desarrollar y utilizar en determinadas explotaciones y especificaciones de producción.</p>

Effect of Blanching and Air Flow Rate on Turmeric Drying

Turmeric processing involves two main steps, blanching and drying. Blanching is a common step in the traditional processing of rhizomes, and hot air drying is an alternative to traditional solar drying. For this study, drying kinetics were performed at different air flow rates (0.2, 0.5, 0.7, 1.2, 2.1, 2.6, 3 and 4m/s) to determine the effect of air flow on the process. To examine the blanching effect, drying kinetics were carried out with blanched and unblanched rhizomes at different temperatures (60, 70, 80, 90 and 100ºC). A diffusion model and two empirical models (Weibull and Peleg) were used to describe mass transfer during drying. The effect of air flow rate on external resistance was observed, and the air velocity transition zone between the external and internal resistance control zone was identified (1–2m/s). Blanching previous to drying increased the process rate at all the temperatures tested, although its effect was reduced when the air drying temperature increased. Empirical models fitted better drying kinetics than the diffusion model, however, the diffusion model provides valuable information about the phenomenon of water removal and scaling up.

Desensitization in ABO-Incompatible Kidney Transplantation With Low ABO Iso-Agglutinin Titers

BACKGROUND

In ABO-incompatible (ABOi) kidney transplantation (KT) with low iso-agglutinin (IG) titers (IGT), standard pre-conditioning treatment might be excessive. To try to answer this question, we evaluated the pre-conditioning requirements of a group of ABOi KT with low ABO IGT in our center. Our main objective was to assess desensitization requirements for ABOi KT with low IGT (<16) at Hospital Clinic of Barcelona from 2006 to 2014.

METHODS

A retrospective study of desensitization (rituximab and plasma exchange [PE]) requirements for ABOi KT with IGT <16 was conducted.

RESULTS

One and 5 years after KT, patient survival was 100%. Renal graft survival was 90% at 1 and 5 years after KT. Mean PE performed before KT was 1.7 (standard deviation [SD], 1.703); 50% of the patients did not receive PE after transplantation, 30% received 2 sessions of PE, and 20% received only 1. The average is 0.8 (SD, 0.91).Follow-up IG determinations remained with low titers (≤8/8). No rebounds of titers were observed during the first 4 to 6 months after transplantation.

CONCLUSIONS

Recipients with IGT ≤8 required none or only 1 PE session to reach acceptable titers (titers ≤4) to perform ABOi KT safely. This information is useful to assess the possibility of a minimized desensitization protocol in ABOi KT donors with low titers of IG to reduce adverse effects, reduce cost, and simplify pre-transplant logistics.

Polonium behaviour in reservoirs potentially affected by acid mine drainage (AMD) in the Iberian Pyrite Belt (SW of Spain)

The province of Huelva is one of the areas most affected by acid mine drainage (AMD) in the world, which can produce big enhancements and fractionations in the waters affected by AMD. There are very few studies on this issue, and none on polonium-210. Twenty-two water reservoirs were sampled, and the (210)Po was measured in both dissolution and particulate phases. The (210)Po concentrations in the waters were in the same order of magnitude to those ones for unperturbed systems, although the data published to particulate matter are very scarce. A mean value and standard uncertainty for (210)Po of 0.25 ± 0.03 mBq L(-1) in the dissolved matter, and 62 ± 9 mBq g(-1) in the particulate matter can be established as base line for the reservoirs of the Huelva area. The distribution coefficients (kd) range from 10(4) to 10(6) L kg(-1), in agreement to the found ones by other authors for the case of neutral waters, but being the lowest values for the more acidic reservoirs. It has been also found that (210)Po has a high tendency to be associated to the particulate matter for neutral-alkaline waters, however, under extreme acid conditions (pH < 3), increases the Po tendency to be associated to the dissolved phase. Therefore, the main conclusion obtained in this work is that AMD has no a significant influence on the total activity concentration of (210)Po in the waters of reservoirs, but the acidity has a clear influence on its distribution between both dissolved and the particulate phases.

Retinal development in the gilthead seabream Sparus aurata

The retinal development of the gilthead seabream Sparus aurata has been analysed from late embryonic development to juvenile stages using classical histological and immunohistological methods. Five significant phases were established. Phases 1 and 2 comprise the late embryonic and hatching stages, respectively. The results indicate that during these early stages the retina is composed of a single neuroblastic layer that consists of undifferentiated retinal progenitor cells. Phase 3 (late prolarval stage) is characterized by the emergence of the retinal layers and the appearance of neurochemical profiles in differentiating photoreceptors, amacrine and ganglion cells. Phases 4 and 5 comprise the late larval and juvenile stages. In these stages, all the retinal cell types can be detected immunohistochemically. All the maturational events described are first detected in the central retina and, as development progresses, spread to the rest of the retina following a central-to-peripheral gradient. The results of this study suggest that S. aurata is an altricial teleost species that hatches with a morphologically undifferentiated retina. The most relevant processes involved in retinogenesis occur during the late prolarval stage (phase 3).

Viral infections of the central nervous system in Spain: a prospective study

The aim of the study was to determine the incidence of viruses causing aseptic meningitis, meningoencephalitis, and encephalitis in Spain. This was a prospective study, in collaboration with 17 Spanish hospitals, including 581 cases (CSF from all and sera from 280): meningitis (340), meningoencephalitis (91), encephalitis (76), febrile syndrome (7), other neurological disorders (32), and 35 cases without clinical information. CSF were assayed by PCR for enterovirus (EV), herpesvirus (herpes simplex [HSV], varicella-zoster [VZV], cytomegalovirus [CMV], Epstein-Barr [EBV], and human herpes virus-6 [HHV-6]), mumps (MV), Toscana virus (TOSV), adenovirus (HAdV), lymphocytic choriomeningitis virus (LCMV), West Nile virus (WNV), and rabies. Serology was undertaken when methodology was available. Amongst meningitis cases, 57.1% were characterized; EV was the most frequent (76.8%), followed by VZV (10.3%) and HSV (3.1%; HSV-1: 1.6%; HSV-2: 1.0%, HSV non-typed: 0.5%). Cases due to CMV, EBV, HHV-6, MV, TOSV, HAdV, and LCMV were also detected. For meningoencephalitis, 40.7% of cases were diagnosed, HSV-1 (43.2%) and VZV (27.0%) being the most frequent agents, while cases associated with HSV-2, EV, CMV, MV, and LCMV were also detected. For encephalitis, 27.6% of cases were caused by HSV-1 (71.4%), VZV (19.1%), or EV (9.5%). Other positive neurological syndromes included cerebellitis (EV and HAdV), seizures (HSV), demyelinating disease (HSV-1 and HHV-6), myelopathy (VZV), and polyradiculoneuritis (HSV). No rabies or WNV cases were identified. EVs are the most frequent cause of meningitis, as is HSV for meningoencephalitis and encephalitis. A significant number of cases (42.9% meningitis, 59.3% meningoencephalitis, 72.4% encephalitis) still have no etiological diagnosis.

[How much should dialysis time be increased when catheters are used?]

The use of central catheters in hemodialysis patients as a permanent vascular access has increased during the last years, reaching numbers of around 7% of prevalent patients and between 25% of incident patients. Although the current catheters allow higher sanguineous flows with smaller incidence of infectious complications and dysfunction, the dose of dialysis that is reached is still inferior to that obtained with native arterio-venous fistula (AVF) and grafts. The aim of the present study was to evaluate the possible additional time supposed by dialysis using central venous catheters with respect to habitual vascular access as a consequence of the lesser blood flow (Qb) and the irregularity of its function (frequent lowering of the Qb and necessity of inverting the lines on many occasions). A total of 48 patients (31 men/17 women) with an average age of 61,6 +/- 14 years old (rank: 28-83), 20 with tunnelled catheter and the remaining with AVF, were included in the study. All the patients were dialyzed in the modality of high flux hemodialysis with a polisulphone of 1,9 m2 dialyzer, dialysis time of 240 minutes, dialysate flow 500 ml/min and monitors equipped with ionic dialysance (ID) with the objective of obtaining a Kt of 45 litres with each one of the different vascular accesses. The patients with AVF received 3 sessions, with variations of Qb to 300, 350 and 400 ml/min. The patients with tunnelled catheter received two sessions, to the maximum Qb, one with normal connection and other with inverted one. In the results obtained it is possible to emphasize that only the patients with AVF and 400 ml/min reached the objective of 45 L of Kt. The patients with AVF needed to increase 12 minutes of hemodialysis with a Qb of 350 ml/min and 28 minutes with a Qb of 300 ml/min; the catheters on normal position needed to increase 24 minutes and finally in the inverted catheters an increase of 59 minutes was necessary to reach the same Kt objective. We concluded that the patients dialyzed with central catheters on average needed to increase by 30 minutes the time of dialysis if the catheter worked in a normal position but 60 minutes if the arterio-venous lines were inverted so as to reach the minimum dose of dialysis.

[Kt as control and follow-up of the dose at a hemodialysis unit]

To ensure our patients are receiving an adequate dose in every dialysis session there must be a target to achieve this in the short or medium term. The incorporation during the last years of the ionic dialysance (ID) in the monitors, has provided monitoring of the dialysis dose in real time and in every dialysis session. Lowrie y cols., recommend monitoring the dose with Kt, recommending at least 40 L in women and 45 L in men or individualizing the dose according to the body surface area. The target of this study was to monitor the dose with Kt in every dialysis session for 3 months, and to compare it with the monthly blood test. 51 patients (58% of our hemodialysis unit), 32 men and 19 women, 60.7+/-14 years old, in the hemodialysis programme for 37.7+/-52 months, were dialysed with a monitor with IC. The etiology of their chronic renal failure was: 3 tubulo-interstitial nephropathy, 9 glomerulonephritis, 12 vascular disease, 7 polycystic kidney disease, 7 diabetic nephropathy and 13 unknown. 1,606 sessions were analysed during a 3 month period. Every patient was treated with the usual parameters of dialysis with 2.1 m2 cellulose diacetate (33.3%), 1.9 m2 polisulfone (33.3%) or 1.8 m2 helixone, dialysis time of 263+/-32 minutes, blood flow of 405+/-66, with dialysate flow of 712+/-138 and body weight of 66.7+/-14 kg. Initial ID, final ID and Kt were measured in each session. URR and Kt/V were obtained by means of a monthly blood test. The initial ID was 232+/-41 ml/min, the final ID was 197+/-44 ml/min, the mean of Kt determinations was 56.6+/-14 L, the mean of Kt/V was 1.98+/-0.5 and the mean of URR was 79.2+/-7%. Although all patients were treated with a minimum recommended dose of Kt/V and URR when we used the Kt according to gender, we observed that 31% of patients do not get the minimum dose prescribed (48.1+/-2.4 L), 34.4% of the men and 26.3% of the women. If we use the Kt individualized for the body surface area, we observe that 43.1% of the patients do not get the minimum dose prescribed with 4.6+/-3.4 L less than the dose prescribed. We conclude that the monitoring of dialysis dose with the Kt provides a better discrimination detecting that between 30 and 40% of the patients perhaps do not get an adequate dose for their gender or body surface area.

A measles outbreak in children under 15 months of age in La Rioja, Spain, 2005-2006

This paper describes a measles outbreak in La Rioja, Spain, which began in December 2005 and mainly affected children under 15 months of age who were not yet immunised with MMR vaccine. The measles cases were detected by the mandatory reporting system, under which laboratories must report every confirmed measles case. Cases were classified in accordance with the National Measles Elimination Plan: suspected and laboratory-confirmed. In the period 14 December 2005 to 19 February 2006, 29 suspected cases of measles were investigated, and 18 were confirmed. The mean incubation period was 13.8 days (range: 9 to 18). Of the 18 confirmed cases, only two were in adults. MMR vaccination was recommended for all household contacts, as well as for children aged 6 to 14 months who attended the daycare centres where the cases had appeared. At these centres, the second dose of MMR was administered ahead of schedule for children under three years of age. It was recommended that the first dose of MMR vaccine be administered ahead of schedule for all children aged 9 to 14 months. During an outbreak of measles, children aged 6 months or older, who have not previously been vaccinated against measles, mumps and rubella, should receive a first dose as soon as possible, and those who have had a first dose should receive a second dose as soon as possible, provided that a minimum of one month has elapsed between the two doses

Modification of pepsinogen I levels and their correlation with gastrointestinal injury after administration of dexibuprofen, ibuprofen or diclofenac: a randomized, open-label, controlled clinical trial

OBJECTIVE

To assess the effect of a 2-week treatment with dexibuprofen, in comparison with ibuprofen and diclofenac, on pepsinogen plasma concentrations and gastrointestinal mucosa, as well as the correlation of these changes with gastrointestinal mucosal injury.

METHODS

60 patients with rheumatologic disease in chronic therapy with NSAID, were included. After a 7-day run-in period patients were randomly assigned to receive a 14-day treatment with dexibuprofen (Group A; Day 1 - 3 = 400 mg t.i.d; Day 4 - 14 = 400 mg b.i.d.), ibuprofen (Group B; Day 1 - 3 = 800 mg t.i.d; Day 4 -14 = 800 mg b.i.d.) or diclofenac (Group C; Day 1 - 3 = 50 mg t.i.d; Day 4 - 14 = 50 mg b.i.d.). Upper gastrointestinal endoscopy (Day 15), capsule-endoscopy (Day 16, 7 patients of each group) and determination of pepsinogen plasma concentrations were performed (basal and Day 15). A semiquantitative scale was designed for the assessment of the gastrointestinal mucosa.

RESULTS

No differences in plasma pepsinogen were found between treatment groups or gastrointestinal injury grades or between basal and post-therapy determinations. Dexibuprofen showed gastroduodenal mucosal injury in fewer patients (42.1%) than was the case with ibuprofen (5%; p = 0.003) and diclofenac (30%; p = N.S.). Dexibuprofen administration was also associated with more patients having no intestinal mucosal damage (42.86% vs. 28.7% in the diclofenac group and 14.29% in the ibuprofen group; p = 0.0175). The rate of clinical adverse events was similar in Groups A, B and C (28%, 38% and 34%).

CONCLUSIONS

Dexibuprofen showed a lower rate of gastroduodenal and intestinal mucosal injury. This effect was not mediated by modifications of plasma pepsinogen levels.

A measles outbreak in children under 15 months of age in La Rioja, Spain, 2005-2006

This paper describes a measles outbreak in La Rioja, Spain, which began in December 2005 and mainly affected children under 15 months of age who were not yet immunised with MMR vaccine. The measles cases were detected by the mandatory reporting system, under which laboratories must report every confirmed measles case. Cases were classified in accordance with the National Measles Elimination Plan: suspected and laboratory-confirmed. In the period 14 December 2005 to 19 February 2006, 29 suspected cases of measles were investigated, and 18 were confirmed. The mean incubation period was 13.8 days (range: 9 to 18). Of the 18 confirmed cases, only two were in adults. MMR vaccination was recommended for all household contacts, as well as for children aged 6 to 14 months who attended the daycare centres where the cases had appeared. At these centres, the second dose of MMR was administered ahead of schedule for children under three years of age. It was recommended that the first dose of MMR vaccine be administered ahead of schedule for all children aged 9 to 14 months. During an outbreak of measles, children aged 6 months or older, who have not previously been vaccinated against measles, mumps and rubella, should receive a first dose as soon as possible, and those who have had a first dose should receive a second dose as soon as possible, provided that a minimum of one month has elapsed between the two doses.

Sepsis and SOFA score: related outcome for critically ill renal patients

AIMS

To evaluate the influence of sepsis in critically ill patients with acute renal failure (ARF), and to analyze the value of the sequential organ failure assessment (SOFA) score for assessing the morbidity and related mortality of these patients.

MATERIAL AND METHODS

A prospective observational study developed in a medical intensive care unit (ICU) of a tertiary care university hospital. Data were collected from January 1, 2001 - July 31, 2002. The inclusion criterion was either a creatinine plasma level > or = 2 mg/dl on ICU admission or increases > or = 30% from its initial value. Sepsis was evaluated at the time of study inclusion, and patients were distributed into 2 groups (septic and nonseptic patients).

RESULTS

Two hundred patients with ARF were prospectively enrolled in the study (91 (45.5%) septic and 109 (54.5%) nonseptic patients). Median age was 68 years in septic patients and 72 in nonseptic ones while the percentage of males in both groups was 66% vs 69%, respectively. Septic patients showed more organ failures and more respiratory, cardiovascular and coagulation failures at the time of study admission as well as a worse mean SOFA score during the first 4 days after inclusion (p < 0.01). Mortality rate at the ICU was significantly higher in the septic group when compared to the nonseptic one (55% vs 19.3%, OR = 2.21 (1.65 - 2.97)). Using stepwise logistic regression, acute tubular necrosis and oliguria in septic patients as well as cardiovascular failure (evaluated by SOFA score) in nonseptic patients were identified as independent risk factors for mortality.

CONCLUSIONS

Septic and nonseptic ICU patients with ARF have an increased risk of ICU mortality depending on the type of organ failure. Although SOFA score does not predict outcome, it is a useful tool to categorize these patients and to describe a sequence of complications in critically ill patients.

Mass transfer enhancement in supercritical fluids extraction by means of power ultrasound

The use of high-intensity ultrasound represents an efficient manner of producing small scale agitation, enhancing mass transfer on supercritical fluids (SF) extraction processes. In this way, a supercritical CO(2) extraction of oil from particulate almonds using power ultrasound was studied. To examine the effect of the acoustic waves all experiments were performed with and without ultrasound. A power ultrasonic transducer for a working frequency of about 20 kHz was constructed and installed inside a high-pressure 5 l SF extractor. The experimental tests were carried out with CO(2) at 280 bar and 55 degrees C. Grounded almonds with an oil content of about 55%, in an amount of 1500 g were deposited inside the SF reactor where the solvent was introduced at a flow rate of 20 kg/h. The results show that the kinetics and the extraction yield of the oil were enhanced by 30% and 20% respectively, when a power of about 50 W was applied to the transducer. The average time of each extraction process was of about 8 h and 30 min. In addition, the transducer was also used as a sensitive probe capable to detect the phase behavior of supercritical fluids when it was driven with low power signals.

[Acute renal failure in critically ill patients. A prospective epidemiological study]

AIMS

To determine factors which may predict mortality in patients admitted to intensive care unit who present acute renal failure.

METHODS

Prospective observational study of the patients admitted to a multidisciplinary intensive care unit over a year. The inclusion criteria were a creatinine plasmatic value > or = 2 mg/dl (177 micromol/l) or an increase (30% or higher) of its basal value on admittance.

RESULTS

One hundred and twenty-seven patients (age = 65.83 +/- 15.06 years; 38% male) with acute renal failure, were prospectively enrolled in the study (13% of intensive care unit admissions). The univariate analysis showed that hospital origin, acute tubular necrosis, late ARF, oliguria, maintained hypotension, sedation or coma, oncological disease and need of mechanical ventilation were significantly associated with mortality (p < 0.05). This association was also found for sepsis (OR: 41.5), multiorganic failure (OR: 3.58) and respiratory, cardiovascular or haematological failure according to the SOFA score. The multivariate analysis found that four clinical variables had an independent predictive value for mortality risk: acute tubular necrosis [OR: 4.57 (2.32-9.00)], use of vasoactive drugs [OR: 2.32 (1.22-4.40)], oliguria [OR: 2.15 (1.12-4.13)] and the acute renal failure starting during admission [OR: 2.06 (1.09-3.88)].

CONCLUSION

Data related to renal failure have worse prognosis than other demographic or clinical data in critically ill patients with acute renal failure. Multicentric studies with unified criteria are needed to analyse the most important prognostic factors.

Effects of supercritical carbon dioxide (SC-CO(2)) oil extraction on the cell wall composition of almond fruits

Extraction of oil from almond fruits using supercritical carbon dioxide (SC-CO(2)) was carried out at 50 degrees C and 330 bar on three sets of almonds: raw almond seeds, raw almond kernels, and toasted almond seeds. Three different oil extraction percentages were applied on each set ranging from approximately 15 to 16%, from approximately 27 to 33%, and from approximately 49 to 64%. Although no major changes were detected in the fatty acid composition between fresh and partially defatted samples, carbohydrate analysis of partially defatted materials revealed important changes in cell wall polysaccharides from almond tissues. Thus, at low extraction percentages (up to approximately 33%), pectic polysaccharides and hemicellulosic xyloglucans were the main type of polymers affected, suggesting the modification of the cell wall matrix, although without breakage of the walls. Then, as supercritical fluid extraction (SCFE) continues and higher extraction rates are achieved (up to approximately 64%), a major disruption of the cell wall occurred as indicated by the losses of all major types of cell wall polysaccharides, including cellulose. These results suggest that, under the conditions used for oil extraction using SC-CO(2), fatty acid chains are able to exit the cells through nonbroken walls; the modification of the pectin-hemicellulose network might have increased the porosity of the wall. However, as high pressure is being applied, there is a progressive breakage of the cell walls allowing the free transfer of the fatty acid chains from inside the cells. These findings might contribute to providing the basis for the optimization of SCFE procedures based on plant food sources.

High frequency of constitutive alkali-labile sites in mouse major satellite DNA, detected by DNA breakage detection-fluorescence in situ hybridization

DNA breakage detection-fluorescence in situ hybridization (DBD-FISH) is a new procedure for detecting and quantifying DNA breaks and alkali-labile sites in single cells. Cells trapped within an agarose matrix are deproteinized and treated with an alkaline unwinding solution that transforms DNA breaks and alkali-labile sites into single-strand DNA (ssDNA) motifs starting from the end of the break. These ssDNA motifs are susceptible to being hybridized with whole genome or specific DNA probes, and detected using current FISH procedures. As DNA breaks increase in a target region, more ssDNA is produced and more DNA probe hybridizes, thus increasing the FISH signal, which may be captured and analyzed using a digital image analysis system. This increase can be reflected in the surface area, mean and whole fluorescence intensity of the signal. When intact mouse splenocytes were processed with this technique using a whole genome probe, a very strong background signal was evident when compared with human blood leukocytes. In fact, when using 0.03M NaOH as the alkaline unwinding solution at 22 degrees C for 2.5min, the whole fluorescence intensity from mice cells was 50 times higher than that from human cells, thus suggesting the existence of a high frequency of constitutive alkali-labile sites in the DNA from mouse cells. Furthermore, when alkaline unwound mouse cells were simultaneously hybridized with the whole genome probe (FITC-revealed, green) and a major satellite DNA probe (Cy-3-labeled, red) both signals appeared co-localized. This result demonstrates that the high frequency of constitutive alkali-labile sites detected in the mouse genome is mainly located in the major satellite DNA sequences, resembling the findings from human 5bp classical satellite DNA sequences.

Prosthetic valve endocarditis caused by Mycoplasma hominis

Mycoplasma hominis endocarditis is extremely uncommon and difficult to diagnose. Atypical growth characteristics in routine bacterial culture and an inability to demonstrate the organism using Gram staining can lead to a delayed diagnosis of Mycoplasma hominis infections, and the organism is often missed. This report describes a patient with Mycoplasma hominis prosthetic valve endocarditis. The microorganism was recovered from the mitral prosthesis but was missed in blood cultures. This finding suggests that Mycoplasma hominis should be considered in the differential diagnosis of culture-negative endocarditis.

[UTIscreen versus UROQUICK: two semiautomatic systems for bacteriuria detection]

BACKGROUND

The aim of the study is to find a rapid and reliable method for urine screen. With this purpose two semiautomatic systems have been evaluated: UTIscreen and UROQUICK.

MATERIAL AND METHODS

We have carried out a prospective study of a total 1,070 urine specimens from patients with suspected urinary infection. Each sample has been inoculated in the two semiautomatic systems and compared with the semiquantitative plate culture as the reference method.

RESULTS

Both semiautomatic systems showed similar specificity and sensitivity at an interpretative breakpoint of 30,000 CFU/ml, with a low number of false positives. Uninfected specimens can be reported the same day of reception.

CONCLUSIONS

Both UTIscreen and UROQUICK systems seem to be adequate for urinary tract infection screening. They are reliable and easy to perform, but in our particular case we find advantage in using UTIscreen because the faster reading of this system makes posible to report the negative results in the same morning of reception of the specimen and do the culture of all the positive samples during our usual working schedule.

Longevity, stress response, and cancer in aging telomerase-deficient mice

Telomere maintenance is thought to play a role in signaling cellular senescence; however, a link with organismal aging processes has not been established. The telomerase null mouse provides an opportunity to understand the effects associated with critical telomere shortening at the organismal level. We studied a variety of physiological processes in an aging cohort of mTR-/- mice. Loss of telomere function did not elicit a full spectrum of classical pathophysiological symptoms of aging. However, age-dependent telomere shortening and accompanying genetic instability were associated with shortened life span as well as a reduced capacity to respond to stresses such as wound healing and hematopoietic ablation. In addition, we found an increased incidence of spontaneous malignancies. These findings demonstrate a critical role for telomere length in the overall fitness, reserve, and well being of the aging organism.

[Control of respiratory monitoring in the critical patient]

This study of the safety of patients undergoing mechanical ventilation was undertaken to ensure correct ventilation and to find quality-control elements for patients and nursing staff. Differences in mode programming and ventilation parameters and their registry at the change of nursing shifts, and correct programming of the sensitivity and minimum minute volume alarms and maximum airway pressure alarms were examined. In a two-month period, 8 cross-sectional studies were made of G1 prevalence in each of three nursing shifts. The status of the alarms and sensitivity were recorded when incorrect, as well as whether the ventilation mode and parameters coincided with the change of nursing shift. An analysis was made of: FiO2, PEEP, respiratory rate, minute volume, tidal volume, support pressure level, and control pressure level depending on the ventilation mode. Corrective measures were applied for a month. The effectiveness of these measures was evaluated by making 8 new G2 cross-sectional studies of the same type. Two hundred forty-eight G1 and 250 G2 recordings were made. The G2 studies revealed a generalized reduction in errors for all parameters. We concluded that the corrective measures were effective so these indicators were included in the monitoring of risk areas in the unit quality control program.

[Survival in patients with sick sinus syndrome and artificial pacemaker. Determining clinical factors]

INTRODUCTION AND OBJECTIVE

The hypothesis that ventricular pacing is the most important factor in the survival of patients with Sick Sinus Syndrome remains controversial. The aim of this report was to determine independent clinical variables to predict survival in paced SSS patients.

METHODS

Retrospective, nonrandomized study of 153 patients with a mean age of 69 +/- 11 years, who received an initial pacemaker for Sick Sinus Syndrome between 1980 and 1994: 65 physiologic pacing (32 dual chamber, 33 atrial) and 88 ventricular pacing mode. After a maximum follow up of 177 months (median 57 months) the end point was total mortality.

RESULTS

Total mortality was 21%. Using univariate analysis, single chamber ventricular pacing, age > or = 70 years and NYHA > or = 2, was associated with a higher risk for total mortality (4 times increased risk for ventricular pacing compared to other pacing modalities). Independent predictors using multivariate analysis were: 1) NYHA > or = 2 (p < 0.05). 2) Coronary artery disease (p < 0.01). 3) Chronic obstructive pulmonary disease (p < 0.05) and 4) Gender (p < 0.05).

CONCLUSIONS

Mortality in patients with the Sick Sinus Syndrome is strongly predicted by preimplant baseline clinical variables. Our data indicate that the role of ventricular pacing mode remains inconclusive. A large, randomized study is necessary to confirm these results.