The Comparative Evaluation of the Performance of Two Phytoremediation Systems for Domestic Wastewater Treatment.

The constructed wetlands as well engineered techniques have been used effectively for phytoremediation of wastewater and pollution control during the last decades. In these technologies, the naturally occurring processes of plants alongside micro-organisms present in the bio-film attached to the roots, soil substrate and water column degrade the organic pollutants. The study seeks to compare the potential use of Phragmites sp. reed bed and floating macrophyte water hyacinth (Eichhornia crassipes) system for domestic wastewater treatment. The sewage treatment performance is evaluated as 80% & 76% chemical oxygen demand (COD), 90% & 87% biological oxygen demand (BOD5), 24% & 18% total dissolved solids (TDS), 69% & 67% total suspended solids (TSS), 12% & 5% Chlorides, 73% & 69% ammonia nitrogen (NH3-N), 42% & 31% phosphate (PO4-P), 93% & 91% most probable number (MPN) and 95% & 92% total viable count (TVC) reduction at optimum hydraulic retention time (HRT) of 24 & 43 h in Phragmites sp. and water hyacinth systems, respectively. Likewise, the floating macrophyte pond contrary to reed bed process shows insignificant pollutant diminution at 24 h HRT. This paper also highlights the microbial population present through the wetland systems by estimation of total viable count (TVC). The botanical aspect with reference to the plant growth is shown a significant increase in vegetation yield. The overall studies indicate the better treatment efficiency by preferred Phragmites sp. root zone system at low foot print area for domestic wastewater.

Comparative evaluation on the performance of bio-rack and shallow pond systems for domestic wastewater treatment.

Constructed wetlands have been used successfully for treatment of wastewater during the last decades. The bio-rack and shallow pond systems are well engineered wetland process in wastewater treatment. The aim of this study is to compare the potential use of bio-rack and shallow pond systems for domestic wastewater treatment either in presence of high total dissolved solids (TDS) or heavy metal salts. The sewage treatment performance indicates 75.15% & 80.93% chemical oxygen demand (COD), 86.59% & 90.90% biological oxygen demand (BOD5), 27.54% & 15.98% total dissolved solids (TDS), 73.13% & 70.31% total suspended solids (TSS), 8.86% & 3.61% Chlorides, 70.22% & 74.18% ammonia nitrogen (NH3-N), 31.71% & 41.24% phosphate (PO4-P), 92.11% & 96.45% most probable number (MPN) and 93.05% & 98.24% total viable count (TVC) reduction at 10 & 21 h hydraulic retention time (HRT) in bio-rack and shallow pond system respectively. Likewise, the Phragmites sp. and water hyacinth can tolerate TDS up to 9000 and 2000 mg/L. The reduction in TDS is minor (14 & 19%) at the highest tolerable limit whereas the heavy metal reduction is 68 & 65%, 69 & 67%, 67 & 63%, 71 & 69% for Cd, Cu, Ni and Zn in bio-rack and shallow pond system respectively. The overall studies indicate the better treatment efficiency in bio-rack system at low foot print area (91 m2) compared to shallow pond system.

Coated stents: local pharmacology.

Despite excellent restoration of acute vessel perfusion, coronary stenting has been limited by subacute thrombosis within 3-10 days and by neointimal proliferation leading to restenosis by 6 months post-intervention. A variety of pharmacotherapeutics have been utilized in an attempt to prevent these sequelae. Drug regimens that reduce thrombosis have the potential for serious toxicities, and no regimen to date has been shown clinically to reduce the incidence of restenosis. Local drug delivery via stents coated with immobilized drug or coated with a drug-releasing polymer matrix offers the possibility of focal therapeutic drug effect within target tissues without serious side-effects arising from systemic drug administration. Before the promise of this treatment modality is realized, however, a more detailed understanding is needed of the local pharmacologic influences on drug activity. Drug-device parameters, such as stent surface area and mode of drug attachment, and drug-tissue parameters, including drug solubility in and non-specific binding to tissues, interact in a complex manner to determine local tissue drug dose, distribution and, consequently, effect.

The cardiac renin-angiotensin-aldosterone system and hypertensive cardiac hypertrophy.

Angiotensin-converting enzyme inhibitors have proven to be uniquely effective in inducing regression, or preventing the occurrence, of ventricular hypertrophy associated with systemic hypertension. This has pointed, for many years, to a possible direct involvement of the renin-angiotensin system in the pathogenesis of cardiac hypertrophy. Over the last 10 years further supporting evidence has been forthcoming about direct trophic effects of angiotensin II in several experimental systems. Additionally, we now have rather conclusive evidence for the existence of a local, intracardiac renin-angiotensin system, which is capable of synthesis of all components of the system, and of cleaving, via the classic pathway, angiotensin peptides from the precursor, angiotensinogen. Moreover, a number of studies have demonstrated the capacity of regulatory response and modulation of activity of the local system in response to a variety of pharmacologic perturbations as well as differential expression of specific components under pathologic conditions, including compensatory hypertrophy and remodeling after myocardial infarction, pressure overload hypertrophy, and volume overload hypertrophy. Continued research into the role of the cardiac renin-angiotensin system in the pathogenesis of cardiac hypertrophy and failure will provide us with the tools to devise more specific, targeted strategies for therapeutic intervention or prevention.

Immunoregulatory effects of superantigens: interactions of staphylococcal enterotoxins with host MHC and non-MHC products.

Staphylococcus aureus carries a highly conserved set of genes which encode a set of secreted enterotoxins. Although it is likely that these enterotoxins affect the host/parasite in favor of the bacterium, we do not understand the molecular basis of this interaction. We summarize recent evidence that defines two types of interaction between the bacterial toxin and host cellular receptors that may subvert the host immune response to S. aureus. An interaction between the toxin and class II products on APC can result in inhibition of costimulatory activity and thus impair clonal expansion of T cells specific for bacterial antigens. Studies using anti-class II antibodies suggest that this may reflect transmission of a negative signal to APC after ligation of class II products. A second interaction between a subset of toxins, including SEC, with non-MHC products stimulates both T-cell proliferation as well as toxin-specific cytotoxic T cells (CTL). We put forward the hypothesis that this interaction reflects binding of a VCAM-1-like subsequence of SEC to VLA-4 expressed by activated target cells. We suggest that this interaction may serve to inhibit the host response by subversion of lymphocyte homing to sites of infection by SEC-producing staphylococci and by local elimination of (VLA-4+) memory T cells.

Primary aortoenteric fistulas.

Aortoenteric fistulas were first reported in 1822. Primary aortoenteric fistulas are uncommon (less than 200 cases reported). Secondary aortoenteric fistulas are a well-recognized complication of prosthetic grafts (incidence from 0.4 to 2.4%). Atherosclerosis, gallstones, foreign bodies, carcinomas, and diverticular disease are the most common etiologies. Diagnosis is difficult with most studies being nondiagnostic. A high incidence of suspicion is required to successfully diagnosis preoperatively. Surgical repair is required for survival of the patients and should consist of the following: 1) primary closure of the intestinal defect, 2) either primary anatomical repair with a prosthetic graft or extra-anatomical vascular reconstruction, depending upon the presence or absence of infection, and 3) treatment with appropriate antibiotics. One of the largest series of primary aortoenteric fistulas from a single institution consisting of three cases secondary to aneurysmal and granulomatous disease is discussed.

Covalent crosslinking analysis of angiotensin receptors on differentiated NG108-15 cells.

Neuroblastoma x glioma hybrid cells (NG108-15) were used as a model system to characterize neuronal-glial type angiotensin (ANG) receptors by covalent crosslinking analysis. After differentiation with 1.5% DMSO and 0.5% fetal bovine serum for four to five days, saturation analysis revealed a single high affinity site with a Kd = 1.35 +/- 0.42 nM and a Bmax = 468 +/- 106 fmol/mg protein. Using the homobifunctional crosslinking reagent bis(sulfosuccinimidyl) suberate (BS3), a site with an estimated Mr of 78 kDa was specifically labeled with 125I-ANG II as determined by SDS-polyacrylamide gel electrophoresis. Both ANG II and ANG III (10(-6) M) inhibited specific labeling. The Ki for ANG III binding was similar by both pharmacologic (Ki = 3.33 +/- 0.98 nM) and gel densitometric (Ki = 2.65 +/- 0.32 nM) analyses. We conclude that the 78 kDa protein represents a high affinity ANG binding site with similar affinities for both ANG II and ANG III.

Effect of angiotensin II and III on inositol polyphosphate production in differentiated NG108-15 hybrid cells.

Neuroblastoma x glioma hybrid cells (NG108-15), differentiated by treatment with 1.5% dimethyl sulfoxide (DMSO) and 0.5% fetal bovine serum, were used to measure the effect of angiotensin II and III (ANG II and ANG III) on the generation of inositol polyphosphates. ANG II increased the synthesis of inositol monophosphates (IP1), inositol diphosphates (IP2), and inositol trisphosphates (IP3) with maximal responses observed at 300, 120, and 30 sec, respectively. The percent increases above basal values at the maximal responses were 140% +/- 9% (IP1), 142% +/- 4% (IP2), and 132% +/- 4% (IP3). This effect was not attenuated by pretreatment of the cells with pertussis toxin. Furthermore, both ANG II and ANG III increased the production of inositol polyphosphates in a dose-dependent manner with ED50 values of 145 nM and 11 nM, respectively. We conclude that differentiated NG108-15 cells express an ANG III selective receptor that mediates phosphatidylinositol breakdown through a pertussis toxin insensitive G-protein.

Traumatic diaphragmatic rupture involving the pericardium.

We have described a case of severe blunt injury to the thorax and abdomen causing an 8 cm laceration of the central tendon of the diaphragm, with extension into the pericardium. Herniation of the apex of the heart through this defect produced hypotension that was unresponsive to fluid resuscitation. Replacement of the heart into the mediastinum promptly restored the blood pressure to satisfactory levels.