Norfloxacin prophylaxis effect on multidrug resistance in patients with cirrhosis and bacterial infections

It is unclear whether norfloxacin predisposes to infections by multidrug-resistant organisms (MDROs). We aimed to evaluate if patients with cirrhosis receiving norfloxacin prophylaxis at the time of the diagnosis of bacterial infections were more likely to present a multidrug-resistant isolate than those without prophylaxis. This is a cross-sectional study of hospitalized patients with cirrhosis and bacterial infections from Argentina and Uruguay (NCT03919032) from September 2018 to December 2020. The outcome variable was a multidrug-resistant bacterial infection. We used inverse probability of treatment weighting to estimate the odds ratio (OR) of norfloxacin on infection caused by MDROs considering potential confounders. Among the 472 patients from 28 centers, 53 (11%) were receiving norfloxacin at the time of the bacterial infection. Patients receiving norfloxacin had higher MELD-sodium, were more likely to have ascites or encephalopathy, to receive rifaximin, beta-blockers, and proton-pump inhibitors, to have a nosocomial or health-care-associated infection, prior bacterial infections, admissions to critical care units or invasive procedures, and to be admitted in a liver transplant center. In addition, we found that 13 (24.5%) patients with norfloxacin and 90 (21.5%) of those not receiving it presented infections caused by MDROs (adjusted OR 1.55; 95% CI: 0.60-4.03; p = 0.360). The use of norfloxacin prophylaxis at the time of the diagnosis of bacterial infections was not associated with multidrug resistance. These results help empiric antibiotic selection and reassure the current indication of norfloxacin prophylaxis in well-selected patients.Study registration number: NCT03919032.

Background elimination and interferometric capability in optical coherence tomography by a nonlinear optical gating based on type-II second-harmonic generation

A novel method that uses nonlinear optical gating to control background illumination in optical coherence tomography is presented. With this method, the user can adjust the amount of undesired backscattering or eliminate it completely, which enables dark-field measurements. The interferometric capability of the method in a nonlinear optical regime is demonstrated with the coupling of three overlapping input waves to yield Fizeau fringes. The measurement of a 265 nm step is performed to validate this method, which was originally conceived for 3D MEMS characterization.

Orthotopic liver transplantation without venovenous bypass: 125 cases from a single center

AIM

This study analyzed a 10-year single-center experience in orthotopic liver transplantation (OLT) without venovenous bypass (VVB).

METHODS

We retrospectively analysed a nonrandomized series (1999-2008) of 125 adult OLT patients without VVB.

RESULTS

The main causes of liver failure were viral hepatitis (n = 39), alcoholic liver disease (n = 22), and liver cancer (n = 17). One-year survival was 76.4%. The most common postoperative complications were bile duct stenosis (n = 12), postoperative bleeding (n = 8), hepatic artery thrombosis (n = 7), and primary liver failure (n = 6). Twelve patients required hemodialysis and four underwent retransplantations of the liver. Fourteen patients died before postoperative day 30(th). Univariate analysis showed significant differences between patients who did and did not survive 30 days among donor death diagnoses (P = .05), red blood cell units transfused (P = .03), aspartate aminotranferase on the first postoperative day (P = .002), ABO type (P = .04), time of orotracheal intubation (P = .001), hemodialysis (P = .001), and period of postoperative vasoactive drug use (P = .006). The total length of orotracheal tube intubation showed a significant independent association with mortality before 30 days (P < .001).

CONCLUSION

OLT without VVB can be safely performed even in severe cases of chronic liver failure.

Effects of neonatal treatment with valproic acid on vasopressin immunoreactivity and olfactory behaviour in mice

Recent findings demonstrate that epigenetic modifications are required for the sexual differentiation of the brain. For example, neonatal administration of the histone deacetylase inhibitor, valproic acid, blocks masculinisation of cell number in the principal nucleus of the bed nucleus of the stria terminalis (BNST). In the present study, we examined the effects of valproic acid on neurochemistry and behaviour, focusing on traits that are sexually dimorphic and linked to the BNST. Newborn mice were treated with saline or valproic acid and the effect on vasopressin immunoreactivity and olfactory preference behaviour was examined in adulthood. As expected, males had more vasopressin immunoreactive fibres than females in the lateral septum and medial dorsal thalamus, which are two projection sites of BNST vasopressin neurones. Neonatal valproic acid increased vasopressin fibre density specifically in females in the lateral septum, thereby reducing the sex difference, and increased vasopressin fibres in both sexes in the medial dorsal thalamus. The effects were not specific to BNST vasopressin projections, however, because valproic acid also significantly increased vasopressin immunoreactivity in the anterior hypothalamic area in both sexes. Subtle sex-specific effects of neonatal valproic acid treatment were observed on olfactory behaviour. As predicted, males showed a preference for investigating female-soiled bedding, whereas females showed a preference for male-soiled bedding. Valproic acid did not significantly alter olfactory preference, per se, although it increased the number of visits females made to female-soiled bedding and the overall time females spent investigating soiled versus clean bedding. Taken together, these results suggest that a transient disruption of histone deacetylation at birth does not have generalised effects on sexual differentiation, although it does produce lasting effects on brain neurochemistry and behaviour.

Complete correction of enzymatic deficiency and neurochemistry in the GM1-gangliosidosis mouse brain by neonatal adeno-associated virus-mediated gene delivery

GM1-gangliosidosis is a glycosphingolipid (GSL) lysosomal storage disease caused by autosomal recessive deficiency of lysosomal acid beta-galactosidase (betagal), and characterized by accumulation of GM1-ganglioside and GA1 in the brain. Here we examined the effect of neonatal intracerebroventricular (i.c.v.) injection of an adeno-associated virus (AAV) vector encoding mouse betagal on enzyme activity and brain GSL content in GM1-gangliosidosis (betagal(-/-)) mice. Histological analysis of betagal distribution in 3-month-old AAV-treated betagal(-/-) mice showed that enzyme was present at high levels throughout the brain. Biochemical quantification showed that betagal activity in AAV-treated brains was 7- to 65-fold higher than in wild-type controls and that brain GSL levels were normalized. Cerebrosides and sulfatides, which were reduced in untreated betagal(-/-) mice, were restored to normal levels by AAV treatment. In untreated betagal(-/-) brains, cholesterol was present at normal levels but showed abnormal cellular distribution consistent with endosomal/lysosomal localization. This feature was also corrected in AAV-treated mice. The biochemical and histological parameters analyzed in this study showed that normal brain neurochemistry was achieved in AAV-treated betagal(-/-) mice. Therefore we show for the first time that neonatal AAV-mediated gene delivery of lysosomal betagal to the brain may be an effective approach for treatment of GM1-gangliosidosis.

[Embolism predictors of infective endocarditis]

The embolic event (EE) increases the morbidity and mortality of infective endocarditis (IE). Prevalence of EE ranges between 22% and 50%, death rates being up to 25% of patients. EE may occur prior to diagnosis, during treatment or afterwards. The objective of this study was to evaluate the demographic, clinical, microbiological, echocardiographic and therapeutic characteristics in patients suffering from IE (with or without emboli) in order to determine predictors for EE. A descriptive study based on observations of patient population diagnosed with IE was conducted at the Hospital Italiano of La Plata during the period March 1996 - December 2004. Fifty-three patients with IE were analyzed (35 without EE and 18 with EE) in retrospect. We found that the presence of vegetations in the transthoracic (TTE) and/or transesophagic (TEE) echocardiographies at the time of diagnosis, the size > or = 10 mm and the compromise of the native mitral valve were the variables that showed significant statistical association with EE to be considered as predictors. The size _ 10 mm was the only variable associated with EE in the logistic regression analysis. During the elective antibiotic treatment, there was a reduction in EE, without their being present from the second week onwards.

Evaluation of the MB/BacT system compared with Middlebrook 7H11 and Lowenstein-Jensen media for detection and recovery of mycobacteria from clinical specimens

MB/BacT vials (an automated system), Middlebrook 7H11 agar plates with the microcolony method for growth detection, and conventional Lowenstein-Jensen egg-based medium were assessed for their rates of recovery, time to detection and ease in aiding the identification of mycobacterial isolates. Of the 2101 consecutive, non-selected specimens for tuberculosis analysed in the laboratory, 158 (7.5%) yielded growth of 159 mycobacteria on at least one of the three media, comprising 111 Mycobacterium tuberculosis and 48 non-tuberculous mycobacteria. Of the 111 specimens positive for M. tuberculosis, 100 isolates were recovered from MB/BacT vials, 99 from M7H11 agar plates, and 86 from Lowenstein-Jensen tubes. The combination of MB/BacT and M7H11 recovered 110 isolates of M. tuberculosis, 107 from M7H11 and Lowenstein-Jensen, and 105 from MB/BacT plus Lowenstein-Jensen. The average time to detection of M. tuberculosis was 11 days with M7H11 using the microcolony method, 16 days with MB/BacT, and 19.5 days with the conventional Lowenstein-Jensen method. The MB/BacT vials recovered greater numbers of non-tuberculous mycobacteria than either of the other two media, but these were considered mostly to be saprophytes. It was concluded that a combination of media was better than a single medium. None of the media combinations showed statistical differences. Use of M7H11 with the microcolony method, which shortens the detection time for mycobacteria and facilitates the detection of mixed cultures, together with the Lowenstein-Jensen tube, was a useful combination.

Does diagnosis determine delivery? The Islington study of older people's needs and health care costs

BACKGROUND

Little is known about the factors associated with the receipt of care by older people. This study investigates the use. costs and factors associated with service usage among people aged 65 or older living in inner London.

METHOD

A community-based survey, using questionnaires, examined psychiatric and physical morbidity, formal and informal care. The relationships between demographic, pathological features and the costs of health and social care were explored using multivariate regression.

RESULTS

A total of 1085 people were interviewed at home of these 18% did not receive any service at all. The total cost of services per week for people with dementia was pound 109, with activity limitation pound 14 and with depression pound 12. The greatest effect of physical limitation was on the receipt of social care. Dementia had the strongest effect on receipt of social care services. Depression increased health care costs to a much greater degree than social care costs. Despite presenting to services, black elders received significantly less health care than other people with the same needs. Older people living alone were more likely to receive social care support and appeared less likely to use health services.

CONCLUSIONS

Physical dependency significantly affects both health and social care costs. Increasing cognitive impairment mainly leads to increasing social care costs. Overall costs are increased by physical dependency, dementia, depression, subjective health problems, living alone and are negatively affected by being black.

Oxygen Is Electroreduced to Water on a “Wired” Enzyme Electrode at a Lesser Overpotential than on Platinum

The first enzyme-based catalyst that is superior to platinum in the four-electron electroreduction of oxygen to water is reported. The smooth Pt cathode reached half and 90% of the mass transport-limited current density at respective overpotentials of -0.4 and -0.58 V in 0.5 M sulfuric acid, and only at even higher overpotentials in pH 7.2 phosphate buffer. In contrast, the smooth "wired" bilirubin oxidase cathode reached half and 90% of the mass transport-limited current density at respective overpotentials as low as -0.2 and -0.25 V. The mass transport-limited current density for the smooth "wired" enzyme cathode in PBS was twice that with smooth Pt in 0.5 M sulfuric acid. Under 1 atm O2 pressure, O2 was electroreduced to water on a polished carbon cathode, coated with the "wired" BOD film, in pH 7.2 saline buffer (PBS) at an overpotential of -0.31 V at a current density of 9.5 mA cm-2. At the same overpotential, the current density of the polished platinum cathode in 0.5 M H2SO4 was 16-fold lower, only 0.6 mA cm-2.

Hepatitis G virus infection in hemodialysis patients and its relationship with hepatitis C virus infection

Our aim was to study the characteristics of hepatitis G virus (HGV) infection in hemodialysis (HD) patients. We evaluated 108 patients from two different units (A: 67 patients; B: 41 patients). HGV RNA and HCV RNA were detected by PCR. Nineteen patients (17.6%) were HGV RNA positive (20.9% in unit A and 12.2% in unit B (NS)). HCV RNA was positive in 19 patients (17.6%) (28.4% in unit A and 0 in unit B (p < 0.01)). Eight patients were HGV RNA and HCV RNA positive (group I), 11 HGV RNA positive (group II), 11 HCV RNA positive (group III), and 78 negative for both viruses (group IV). Time on HD was 51.3 +/- 37.0 months for group I, 36.0 +/- 27.9 months for group II, 63.5 +/- 40.2 months for group III, and 26.4 +/- 27.1 months for group IV (p < 0.01 for I and III). Seven patients (87.5%) from group I, 9 (81.8%) from group II, 10 (90.9%) from group III, and 44 (56.4%) from group IV had a history of transfusion (p < 0.03 for I, II and III). Two patients (25%) from group I, none from group II, 5 (45.4%) from group III, and 6 (7.7%) from group IV had chronic ALAT elevation (p < 0.01 for I and III). We conclude that HGV infection was frequent in our HD patients, related to transfusions and independent of HCV prevalence, and that HGV infection itself was not a cause of ALAT elevation suggesting chronic hepatitis.

CarboMedics and Monostrut valves: clinical and hemodynamic outcomes in a randomized study

BACKGROUND AND AIM OF THE STUDY

Our aim was to compare the CarboMedics (CM) and Monostrut (M) mechanical heart valve prostheses in the aortic position. These prostheses have been studied extensively in the past, both have well-defined characteristics, and have not been modified for many years.

METHODS

This randomized, prospective study included 200 consecutive patients; 100 received the CM prosthesis and 100 the M prosthesis. Both groups were statistically similar in terms of age, aortic valve lesion, and preoperative clinical and surgical characteristics. Mean follow up was 5.58 years (range: 2 months to 11 years); total follow up was 1095 patient-years (pt-yr) (CM 5.33 years, 528 pt-yr; M 5.85 years, 567 pt-yr).

RESULTS

Early mortality rates were 1% in the CM group and 3% in the M group. Late mortality rates were 7% and 9%, respectively. Mean (+/- SD) survival rates at 11 years were 80.51 +/- 7.36% for the CM group and 79.62 +/- 5.59% for the M group. There were no cases of mechanical valve failure in either group. The linearized rates of major thromboembolism were 1.03% and 0.20% per pt-yr for the CM and M groups, respectively; the rates of major bleeding-events were 0.71% and 0.61% per pt-yr, respectively. The rate of paravalvular leak was 0.35% and 0% per pt-yr in the CM and M groups, respectively. Postoperative NYHA class was I-II in 95.83% of CM patients, and in 94.37% of M patients.

CONCLUSION

Clinical results with CarboMedics and Monostrut prostheses are highly satisfactory, but no superiority of one valve over the other can be identified.

Annulling parasitic fringes in real time holographic interferometry: a new method

A method for annulling parasitic fringes in real time holographicin terferometrya nd its theoreticalj ustification is presented. The main advantage relates to cancellation of nondesired object motions or deformations with experimental simplicity.

CBXC: a set of recombinant inbred strains between CBA/Ca and BALB/c

A new set of nine recombinant inbred strains designated CBXC-1 to CBXC-9 has been developed from a cross between CBA/Ca female and BALB/c male mice. All of the strains have been brother x sister mated for more than 20 generations, and have been characterized at eight electrophoretic, one immunological and two coat colour loci at which the progenitor strains differ. This set of strains should be useful in investigating the genetics of any characters which differ between the two progenitor strains.

Genetic monitoring of rat strains using monoclonal antibodies specific for polymorphic class I and class II MHC antigens

An enzyme-linked immunoassay using monoclonal antibodies, specific for polymorphic class I and class II MHC antigens distributed among inbred, congenic and hybrid strains of rats, was developed, in order to provide an easy means of identifying different strains of rats by typing their blood cells.

Genetic monitoring of inbred strains of mice using monoclonal antibodies to major histocompatibility haplotypes and lymphocyte alloantigens

An enzyme immunoassay procedure is described for the identification of major histocompatibility haplotypes and lymphocyte alloantigens in 19 inbred mouse strains. The assay was found to be useful for the genetic monitoring of such mice.

A comparison of the analytical ultracentrifuge and high-performance liquid chromatography for the determination of molecular weight distributions of plasma protein fraction (human)

The use of high-performance liquid chromatography (HPLC) with size exclusion column packings is investigated as an alternate assay method to the analytical ultracentrifuge, when assaying for the high molecular weight components of human plasma protein fraction. Results indicate that HPLC is a more accurate and precise method for assaying high molecular weight components in plasma protein fraction, even when present in small amounts.

Highly purified sarcoplasmic reticulum vesicles are devoid of Ca2+-independent ('basal') ATPase activity

On solubilization with Triton X-100 of sarcoplasmic reticulum vesicles isolated by differential centrifugation, the Ca2+-ATPase is selectively extracted while approximately half of the initial Mg2+-, or 'basal', ATPase remain in the Triton X-100 insoluble residue. The insoluble fraction, which does not contain the 100 000 dalton polypeptide of the Ca2+-ATPase, contains high levels of cytochrome c oxidase. Furthermore, its Mg2+-ATPase activity is inhibited by specific inhibitors of mitochondrial ATPase, indicating that the 'basal' ATPase separated from the Ca2+-ATPase by detergent extraction originates from mitochondrial contaminants. To minimize mitochondrial contamination, sarcoplasmic reticulum vesicles were fractionated by sedimentation in discontinuous sucrose density gradients into four fractions: heavy, intermediate and light, comprising among them 90-95% of the initial sarcoplasmic reticulum protein, and a very light fraction, which contains high levels of Mg2+-ATPase. Only the heavy, intermediate and light fractions originate from sarcoplasmic reticulum; the very light fraction is of surface membrane origin. Each fraction of sarcoplasmic reticulum origin was incubated with calcium phosphate in the presence of ATP and the loaded fractions were separated from the unloaded fractions by sedimentation in discontinuous sucrose density gradients. It was found that vesicles from the intermediate fraction had, after loading, minimal amounts of mitochondrial and surface membrane contamination, and displayed little or no Ca2+-independent basal ATPase activity. This shows conclusively that the basal ATPase is not an intrinsic enzymatic activity of the sarcoplasmic reticulum membrane, but probably originates from variable amounts of mitochondrial and surface membrane contamination in sarcoplasmic reticulum preparations isolated by conventional procedures.

Effects of somatostatin on gastric mucosal histamine and serotonin content in restrained rats

The effects of continuous intravenous perfusion of somatostatin on the incidence of ulcers and the histamine and serotonin gastric mucosal content in rats subjected to 12 h of restraint were studied. 51 sets of Sprague-Dawley male rats (102 animals) were divided at random into two groups. Those in group I were immobilized and treated with an intravenous infusion of isotonic saline solution. Animals in group II were also immobilized and given intravenous cyclic somatostatin dissolved in isotonic saline solution; the initial dose was 25 microgram and a continuous infusion of 2.5 microgram/kg/h was administered thereafter. A decrease in the ulcer index was observed in the rats perfused with somatostatin (p less than 0.01) as well as a decrease in the histamine (p less than 0.001) and serotonin (p less than 0.01) gastric mucosal contents. These effects of somatostatin on restraint-induced stress ulcer in rats are probably to be explained by microcirculatory changes in the gastric mucosa determined by the vasoactive amines (histamine and serotonin). They constitute an important factor in the pathogenesis of these lesions.