Chemical resistance of the gram-negative bacteria to different sanitizers in a water purification system

Background  

Purified water for pharmaceutical purposes must be free of microbial contamination and pyrogens. Even with the additional sanitary and disinfecting treatments applied to the system (sequential operational stages), Pseudomonas aeruginosa, Pseudomonas fluorescens, Pseudomonas alcaligenes, Pseudomonas picketti, Flavobacterium aureum, Acinetobacter lowffi and Pseudomonas diminuta were isolated and identified from a thirteen-stage purification system. To evaluate the efficacy of the chemical agents used in the disinfecting process along with those used to adjust chemical characteristics of the system, over the identified bacteria, the kinetic parameter of killing time (D-value) necessary to inactivate 90% of the initial bioburden (decimal reduction time) was experimentally determined.     

Surgical delivery of drug releasing poly(lactic-co-glycolic acid)/poly(ethylene glycol) paste with in vivo effects against glioblastoma

Introduction

The median survival of patients with glioblastoma multiforme (astrocytoma grade 4) remains less than 18 months despite radical surgery, radiotherapy and systemic chemotherapy. Surgical implantation of chemotherapy eluting wafers into the resection cavity has been shown to improve length of survival but the current licensed therapy has several drawbacks. This paper investigates in vivo efficacy of a novel drug eluting paste in glioblastoma.

Methods

Poly(lactic-co-glycolic acid)/poly(ethylene glycol) (PLGA/PEG) self-sintering paste was loaded with the chemotherapeutic agent etoposide and delivered surgically into partially resected tumours in a flank murine glioblastoma xenograft model.

Results

Surgical delivery of the paste was successful and practical, with no toxicity or surgical morbidity to the animals. The paste was retained in the tumour cavity, and preliminary results suggest a useful antitumour and antiangiogenic effect, particularly at higher doses. Bioluminescent imaging was not affected significantly by the presence of the paste in the tumour.

Conclusions

Chemotherapy loaded PLGA/PEG paste seems to be a promising technology capable of delivering active drugs into partially resected tumours. The preliminary results of this study suggest efficacy with no toxicity and will lead to larger scale efficacy studies in orthotopic glioblastoma models.     

Predictors of developmental disabilities after open heart surgery in young children with congenital heart defects

OBJECTIVES: To determine the prevalence of persistent developmental impairments in children with congenital heart defects and to identify factors that enhance risk for an adverse outcome. STUDY DESIGN: Eligible infants (n = 131) <2 years of age requiring open heart surgery were recruited prospectively. Subjects were assessed during surgery and again 12 to 18 months later with standardized developmental assessments and formal neurologic examinations. RESULTS: Mean age at follow-up testing was 19.1 +/- 6.6 months. Assessments indicated that 41% had abnormal neurologic examinations. Gross and/or fine motor delays were documented in 42%, and 23% demonstrated global developmental delay. Univariate and multiple regression models identified the following factors increasing the risk for persistent developmental deficits: preoperative and acute postoperative neurodevelopmental status and microcephaly, type of heart lesion, length of deep hypothermic circulatory arrest, age at surgery, and days in the intensive care unit (P <.05). CONCLUSIONS: Children with congenital heart defects commonly have ongoing neurologic, motor, and developmental deficits well after surgical correction. The cause is multifactorial and includes brain injury before, during, and after heart surgery.     

Noncardiogenic pulmonary edema caused by decompression sickness: rapid resolution following hyperbaric therapy

Noncardiogenic pulmonary edema is a recognized but uncommon manifestation of type 2 decompression sickness. It typically occurs within 6 hours of a dive. Because the adult respiratory distress syndrome in this setting is believed to be due to microbubbles in the pulmonary vasculature, recompression in a hyperbaric chamber has been recommended as a form of therapy. A patient developed noncardiogenic pulmonary edema following a seawater dive to 75 feet. There was complete radiologic and clinical resolution within 5 hours of hyperbaric therapy.     

Cardiovascular response to acute hypoxemia in adult rats hypoxemic neonatally.

OBJECTIVE: To determine the effects of chronic hypoxemia neonatally on the cardiovascular response to acute hypoxemia in adulthood. METHODS: Experiments were conducted on adult rats (82+/-2 days) which had been made chronically hypoxemic (hypobaric hypoxia equivalent to FiO(2)=0.14) during the first ten days of life but raised in room air (Neonatally Hypoxemia) as well as on adult rats never previously hypoxemic (Control). The animals were instrumented with catheters in the right common carotid artery and superior vena cava for measurements of mean systemic arterial pressure (MAP), central venous pressure, heart rate (HR), arterial blood gases, and arterial as well as mixed venous O(2) saturation. Oxygen consumption (VO(2)) was measured allowing calculation of cardiac index (CI), stroke volume index (SVI) and systemic vascular resistance index (SVRI). The rats were made acutely hypoxemic by exposure to FiO(2)=0.10 for 20 min. RESULTS: HR increased and MAP decreased to similar extents in both groups during acute hypoxemia. However, SVI and CI increased significantly (P<0.05) during acute hypoxemia in the Neonatally Hypoxemic group (24+/-6%, 41+/-8%) but respectively decreased and did not change in the Control animals (-13+/-6%, 2+/-6%). SVRI fell significantly more during hypoxemia in the Neonatally Hypoxemic animals than in the Control group (36+/-4% vs. 14+/-5%). CONCLUSIONS: Hypoxemia experienced in early life has long-term effects on the cardiovascular response to acute hypoxemia at maturity. This may have important implications for individuals hypoxemic in early life due to congenital cyanotic heart defects or pulmonary disease secondary to prematurity.