Impact of antiretroviral therapy on decreasing hospitalization rates of HIV-infected patients in 2001

Effective antiretroviral therapy initially resulted in large decreases in hospitalization rates of HIV-infected patients. The goal of this study was to determine whether these gains were being maintained in 2001. A cross-sectional study of hospital admission characteristics during four time periods was performed. All patients receiving care at the HIV clinics of New York Presbyterian Hospital-Cornell Medical Center (NYPH) in New York City were included. In 1995, 883 outpatients were receiving care for HIV infection at NYPH; this increased to 1990 outpatients by 2001. Demographic and laboratory information was obtained for these outpatients, and diagnoses were recorded for all patients requiring hospitalization on at NYPH during the time periods January 1 through June 30, in 1995, 1997, 1999, and 2001. The incidence of hospital admission declined in all four time periods: 1995 (95 per 100 patient-years [pt-yr]), 1997 (48 per 100 pt-yr), 1999 (38 per 100 pt-yr, p < 0.05), and 2001 (25 per 100 pt-yr). The incidence of bacterial pneumonia and opportunistic infections (OIs) decreased in all four time periods. The median hospitalization were CD4(+) cell count for outpatients increased from 231 (1995) to 364 (2001). Important predictors of hospitalization were CD4(+) < 200, and IVDU as an HIV risk factor. Since 1995 and the introduction of highly active antiretroviral therapy, continuing increases in CD4(+) cell counts of outpatients has been reflected in persistent declines in hospitalization rates. Large decreases in OIs and pneumonia have been minimally offset by stable rates of hospital admissions for diagnoses such as hepatitis, cirrhosis, and cellulitis.     

New atrial arrhythmia occurrence in single chamber implantable cardioverter defibrillator patients: A real-world investigation

Introduction

A current limitation of single chamber implantable cardioverter defibrillators (ICDs) is the lack of an atrial lead to reliably detect atrial fibrillation (AF) episodes. A novel ventricular based atrial fibrillation (VBAF) detection algorithm was created for single chamber ICDs to assess R-R variability for detection of AF.

Methods

Patients implanted with Visia AF™ ICDs were prospectively enrolled in the Medtronic Product Surveillance Registry from December 15, 2015 to January 23, 2019 and followed with at least 30 days of monitoring with the algorithm. Time to device-detected daily burden of AF ≥ 6 min, ≥6 h, and ≥23 h were reported. Clinical actions after device-detected AF were recorded.

Results

A total of 291 patients were enrolled with a mean follow-up of 22.5 ± 7.9 months. Of these, 212 (73%) had no prior history of AF at device implant. However, 38% of these individuals had AF detected with the VBAF algorithm with daily burden of ≥6 min within two years of implant. In these 80 patients with newly detected AF by their ICD, 23 (29%) had a confirmed clinical diagnosis of AF by their provider. Of patients with a clinical diagnosis of AF, nine (39%) were newly placed on anticoagulation, including five of five (100%) patients having a burden >23 h.

Conclusions

Continuous AF monitoring with the new VBAF algorithm permits early identification and actionable treatment for patients with undiagnosed AF that may improve patient outcomes.     

Four new cases of stomatin-deficient hereditary stomatocytosis syndrome: association of the stomatin-deficient cryohydrocytosis variant with neurological dysfunction

This report concerns congenitally Na(+)-K(+) leaky red cells of the 'hereditary stomatocytosis' class. Three new isolated cases and one new pedigree are described, and one previously reported case is expanded. In all cases, Western blotting of red cell membranes revealed a deficiency in the 32 kDa membrane protein, stomatin. All showed pronounced cation leaks at 37 degrees C with markedly abnormal intracellular Na(+) and K(+) concentrations, like all other such stomatin-deficient cases. Consistent with recent findings in two previously described British pedigrees, immunocytochemistry demonstrated that the deficiency of stomatin was not complete. On typical blood films, some red cells showed positive stomatin immunoreactivity, while most were negative, although in one case only a minority were negative. All platelets and neutrophils were stomatin positive. The cases differed markedly between themselves with regard to the temperature dependence of the passive leak to K(+). Three showed a simple monotonic temperature dependence, while two showed a minimum at around 20-25 degrees C, such that the cells were extremely leaky at 0 degrees C, giving the phenotype known as 'cryohydrocytosis'. These patients are the only two known cases of stomatin-deficient cryohydrocytosis. Both showed a congenital syndrome of mental retardation, seizures, cataracts and massive hepatosplenomegaly, probably defining a new haemato-neurological syndrome.     

Gene expression profiling of bronchoalveolar lavage cells in acute lung rejection

Lung transplantation is effective for many diseases that are unresponsive to other therapy. However, long-term survival of recipients is limited by the development of bronchiolitis obliterans syndrome. Acute rejection is a major risk factor for bronchiolitis obliterans syndrome, but noninvasive biomarkers have not been identified. To address this deficiency, gene expression microarrays were performed using bronchoalveolar lavage cells of lung transplant recipients with acute rejection (n = 7) and with no rejection (n = 27). The cell and differential counts were similar. Signal values for genes between groups were compared using t tests. One hundred thirty-five genes were upregulated in the acute-rejection group, including genes involved in acute rejection, immune response genes with an unknown role in rejection, genes not known to have a role in rejection, and genes of unknown function. Two-dimensional hierarchical clustering grouped all acute rejection samples into one cluster and the majority of the no-rejection samples into a second cluster. The acute-rejection samples showed significant changes in gene expression for seven biological pathways. Bronchoalveolar lavage cells are a reliable RNA source for microarray analysis, which is powerful in identifying acute-rejection genes. The individual genes, patterns of gene expression, or biologic pathways identified may represent novel biomarkers for acute rejection.     

Microprocessor control of intra-aortic balloon pumping

An automatic control scheme for the control of intra-aortic balloon pumping has been implemented on a Digital Equipment Corporation LSI-11 micro-processor system and tested in experiments conducted on a mock circulatory loop as well as in a series of acute animal experiments. The control algorithm employed by the digital controller (LSI-11) is identical in form to that employed by Clark et al. (3), and consists of [1] the beat-by-beat evaluation of a performance index that reflects the objectives of balloon pumping, and [2] the adjustment of balloon inflation and deflation times within the diastolic period so as to maximize this performance index according to a steepest ascent algorithm. In order to reduce convergence time and minimize disturbances around the optimum operating point, a scheme that reduces search step size as the search proceeds from initial values is also incorporated in the algorithm. Importantly, this system obeys a bedside measurement constraint in that it requires only readily available physiologic signals for its operation; the ECG for timing purposes, and the central aortic pressure for evaluation of the system performance index. A number of conventional safety features are also implemented in the controller to, for example, guard against untimely balloon inflation in the occurrence of aberrant heart beats. Finally, the ability of this digital controller to reach an optimum independent of the dynamics of the particular pneumatic pumping system utilized, coupled with the flexibility in design capability and relatively low cost of implementation via the microprocessor system, provide a significant advance in the area of the automatic control of intra-aortic balloon pumping.     

Myocardial potassium balance associated with regional ischaemia in the pig: effects of beta-adrenoceptor blockade, duration of ischaemia and preceding ischaemic periods.

The effects of beta-adrenoceptor blockade, duration of ischaemia and preceding ischaemic periods on ischaemia-induced changes in myocardial K+ balance were studied in 12 open-chest pigs. Coronary venous blood was directed through a shunt from the coronary sinus to the right atrium. Continuous recordings of arterial, shunt blood [K+] and shunt flow enabled us to compute myocardial K+ balance during and after consecutive 2-, 2-, 5-, 10- and 2-min periods of regional ischaemia separated by 30 min of reperfusion. beta-adrenoceptor blockade (propranolol 1 mg kg-1 i.v.) given between the first and second ischaemic period did not alter the effects of 2 min ischaemia on myocardial K+ balance. Total K+ losses induced by 2, 5 and 10 min of ischaemia were 67.1 (40.6-93.3), 106.7 (69.4-176.8) and 192.2 (117.7-332.6) mumol 100 g-1, respectively. Thus, the plateau observed in extracellular [K+] between 2 and 10 min of regional ischaemia could, at least partly, be explained by continuous drainage of K+ from ischaemic myocardium into the surrounding normally perfused tissue. The total K+ loss induced by the second and last 2-min ischaemic period were 67.1 (40.6-93.3) and 35.6 (23.1-53.6) mumol 100 g-1 (P less than 0.001), respectively. This reduction shows that ion homeostasis during ischaemia was greatly changed in myocardium which had been 'preconditioned' and 'stunned' by 5 plus 10 min of ischaemia. Total amount, maximal rate and duration of post-ischaemic K+ reuptake increased with the duration of the preceding ischaemia. Moreover, K+ re-uptake after 2 min of ischaemia and the number of sarcolemmal Na/K pumps ([3H]ouabain binding), were normal in stunned myocardium. From these observations we conclude that progressive stimulation of the Na/K-pump occurred when ischaemia was prolonged from 2 to 10 min, and that Na/K-pump function was preserved in stunned myocardium.     

Acyclovir prophylaxis of varicella in children with renal disease receiving steroids

Varicella, or chickenpox, is very communicable and has been shown to be transmitted to nearly 90% of household contacts. Severe varicella infections with fatal complications have been noted in children receiving corticosteroids despite the administration of varicella-zoster immune globulin (VZIG). The use of post-exposure acyclovir prophylaxis in immunocompetent children exposed to a household contact with varicella has been shown to decrease the transmission rate of varicella significantly. We studied the safety and efficacy of acyclovir prophylaxis as an adjunctive preventive measure in 8 children (10 separate exposures) receiving corticosteroids for renal disease. Four children (6 separate exposures) served as controls. No adverse reactions were reported with the acyclovir prophylaxis. The maximum change between pre- and study serum creatinine levels was 0.1 mg/dl. None of the 8 patients who received acyclovir prophylaxis developed chickenpox. One of these 8 patients developed humoral immunity to varicella despite the absence of clinical infection. One of 4 patients who received VZIG prophylaxis alone developed chickenpox. These data support the use of acyclovir prophylaxis as an adjunctive measure to VZIG for the prevention of potentially serious varicella infection in children receiving steroids. Received: 12 February 1999 / Revised: 7 June 1999 / Accepted: 7 June 1999     

An efficient green protocol for the synthesis of 1,2,4,5-tetrasubstituted imidazoles in the presence of ZSM-11 zeolite as a reusable catalyst

In this study, we have synthesized a series of ZSM-11 zeolite catalysts using tetrapropyl ammonium hydroxide as a structure-directing agent through a highly efficient hydrothermal method. The series of catalysts were studied by different techniques such as FT-IR spectroscopy, XRD, FE-SEM, HR-TEM, EDS, pyridine-FT-IR spectroscopy, and BET analysis. We focused on varying reaction time intervals from 18 to 48 hours to investigate the effect on catalytic activities of the synthesized series of catalysts. The percentages of aluminum increased in the framework of zeolites with increasing crystallinity, surface area, external surface area, and acidity in the series of ZSM-11 zeolites by increasing the time from 18 to 48 h. Then, we studied the catalytic activity of a series of ZSM-11 zeolites and found that the ZSM-11 zeolite (48 h) possesses higher catalytic activity towards the synthesis of 1,2,4,5-tetrasubstituted imidazoles under solvent-free conditions. The present protocol scored well with excellent yield, short reaction time, clean reaction profiles, low catalyst loading, and no tedious workup. The catalyst (ZSM-11 zeolite 48 h) was recycled and reused in five runs without any considerable loss of activity and product yield.

We synthesized a series of ZSM-11 zeolite catalysts, investigating the effect of varying the reaction time interval from 18 to 48 h. The ZSM-11 zeolite (48 h) has higher catalytic activity for the synthesis of 1,2,4,5-tetrasubstituted imidazoles.