39 research outputs found
Assessing Arrhythmia Risk in Diabetic and Ischemic-preconditioned Rat Hearts
The purpose of this study is to understand the extent of protection against arrhythmia that Streptozotocin (STZ) induced diabetes and ischemic-preconditioning (IPC) on Sprague-Dawley rat hearts subjected to ischemia-reperfusion injury. Hearts were extracted and perfused using the langendorff method with aerated Krebs Henseleit solution. ECG recordings were recoded as the hearts were subjected to 35 minute baseline, 30 minute of no flow (ischemia) followed by 1 hour of reperfusion. The four groups investigated were vehicle control, Streptozotocin (STZ) induced diabetic rats (65mg/kg STZ), ischemic preconditioned hearts (IPC) that were subjected to two 3 minute ischemic intervals followed by 5 and 10 minute reperfusion intervals respectively), and finally diabetic hearts that underwent ischemic preconditioning (STZ+IPC). The time elapsed during ischemia until all ventricular activation stops for control hearts is 7.1±0.8 minutes, while STZ, IPC, and IPC + STZ are 15.5± 3.7, 8.6± 0.9 and 9.9± 1.6 minutes respectively. The STZ group was significantly different from the control group. When the time spent by each heart in the normal sinus rhythm state was analyzed during the 60-minute reperfusion period, control animals maintained normal rhythm for 20.9±9 minutes while STZ, IPC, and IPC + STZ maintained 29.6± 12.4, 31.7± 10.2, and 40.94+ 9.6 minutes respectively. Furthermore, the time spent in ventricular fibrillation (VF) was analyzed, and the IPC+STZ group spent 0.24± 0.2 minutes while control hearts spent 11.28± 9.2 minutes in VF. The data suggests a trend of improved arrhythmia protection when treated with STZ, IPC, or both. The IPC+STZ group is potentially displaying an additive cardioprotective effect
Recommended from our members
Nursing considerations to complement the Surviving Sepsis Campaign guidelines
Objectives: To provide a series of recommendations based on the best available evidence to guide clinicians providing nursing care to patients with severe sepsis.
Design: Modified Delphi method involving international experts and key individuals in subgroup work and electronic-based discussion among the entire group to achieve consensus.
Methods: We used the Surviving Sepsis Campaign guidelines as a framework to inform the structure and content of these guidelines. We used the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) system to rate the quality of evidence from high (A) to very low (D) and to determine the strength of recommendations, with grade 1 indicating clear benefit in the septic population and grade 2 indicating less confidence in the benefits in the septic population. In areas without complete agreement between all authors, a process of electronic discussion of all evidence was undertaken until consensus was reached. This process was conducted independently of any funding.
Results: Sixty-three recommendations relating to the nursing care of severe sepsis patients are made. Prevention recommendations relate to education, accountability, surveillance of nosocomial infections, hand hygiene, and prevention of respiratory, central line-related, surgical site, and urinary tract infections, whereas infection management recommendations related to both control of the infection source and transmission-based precautions. Recommendations related to initial resuscitation include improved recognition of the deteriorating patient, diagnosis of severe sepsis, seeking further assistance, and initiating early resuscitation measures. Important elements of hemodynamic support relate to improving both tissue oxygenation and macrocirculation. Recommendations related to supportive nursing care incorporate aspects of nutrition, mouth and eye care, and pressure ulcer prevention and management. Pediatric recommendations relate to the use of antibiotics, steroids, vasopressors and inotropes, fluid resuscitation, sedation and analgesia, and the role of therapeutic end points.
Conclusion: Consensus was reached regarding many aspects of nursing care of the severe sepsis patient. Despite this, there is an urgent need for further evidence to better inform this area of critical care
Tumor-associated antigens in bilateral breast cancer.
The purpose of our present study is to determine whether monoclonal antibodies can define an antigenic phenotype which expresses itself in a concordant fashion in synchronous bilateral breast cancer. The monoclonal antibodies DF.3 and B72.3 were reacted (ABC immunoperoxidase) with formalin-fixed, paraffin-embedded sections of bilateral synchronous breast cancers from 19 patients. MAb DF.3 demonstrated a P less than .01 correlation of right-sided vs left-sided reactivity. This suggested that MAb DF.3 could be used as a biologic marker for synchronous bilateral breast cancer. We hypothesized that the majority of clinically asynchronous breast cancers are really biologically synchronous. We used the immunoperoxidase technique in a similar fashion on bilateral metachronous tumors in 17 patients. DF.3 antigen expression correlated (right to left side) at P less than .01 value. This data, supported by previous information, suggests that the term metachronous breast cancer is a clinically arbitrary definition but that biologically most metachronous cancers may well be synchronous
Reactivity of the monoclonal antibody B72.3 with fetal antigen: correlation with expression of TAG-72 in human carcinomas.
The monoclonal antibody (MAb) B72.3 recognizes a mucin-like glycoprotein, TAG-72, which has been detected in a spectrum of human carcinomas, but not in the normal tissue counterparts. Using avidin-biotin-peroxidase complex (ABC) immunohistochemical techniques, MAb B72.3 was reacted with formalin-fixed, paraffin-embedded fetal and pediatric tissue sections to determine the extent of expression of the recognized antigen in these tissues. First trimester fetal tissues failed to express detectable antigen. Gastrointestinal epithelia from 13 to 34 weeks gestation demonstrated the most immunoreactivity with B72.3 although bronchial respiratory epithelium of the lung, transitional epithelium from the kidney, Hassall\u27s corpuscles of the thymus, and gonadal tissues from fetuses of both sexes were also reactive. The TAG-72 antigen was not detected in fetal breast, pancreas, liver, spleen, adrenal, or heart. Expression of the TAG-72 antigen in malignancy appears to correlate well with fetal tissue reactivity with B72.3
A tumor-associated antigen in carcinoma of the pancreas defined by monoclonal antibody B72.3.
A retrospective analysis of 25 primary adenocarcinomas of the pancreas, 16 metastatic pancreatic tumors, 8 cases of chronic pancreatitis, and 3 adult normal pancreas was performed to ascertain the reactivity of monoclonal antibody (MAb) B72.3 to malignant and nonneoplastic pancreatic lesions. Formalin-fixed, paraffin-embedded sections of pancreas were evaluated by immunohistochemical techniques (avidin-biotin-peroxidase complex [ABC] method). Twenty-one of 25 malignant primary tumors were reactive, and all 16 metastatic sites expressed the B72.3 antigen. In contrast, all cases of pancreatitis and normal pancreas were either weakly reactive or nonreactive. Ten malignant and two benign pancreatic fine-needle aspirates provided results similar to those seen with fixed tissues. Because MAb B72.3 has selective reactivity for primary and metastatic pancreatic cancer, it may be of value as a diagnostic adjunct in cytologic examination or for radioimmunodetection of regional and/or distant metastases of adenocarcinoma of the pancreas
A comparison of tumor-related antigens in male and female breast cancer.
A retrospective analysis was undertaken in which 15 female and 15 male breast cancers were matched by age, stage, estrogen receptor status, and histologic type. Our protocol compares male and female breast cancers for reactivity with antibodies against tumor-associated antigens known to be present on female breast cancer cells. Formalin-fixed sections of each primary tumor were reacted in the ABC immunoperoxidase assay against antibodies B72.3 and DF.3 and an antibody to the ras p21 antigen. Reactivity to B72.3 and DF.3 was similar. However, the ras p21 antigen was expressed to a significantly greater extent in female breast cancers (p = .0008). Thus, although there are similarities in antigenic phenotype of male and female breast cancers, some female breast cancers may have a different pathogenesis as demonstrated by increased amounts of a specific oncogene product
Rapid Magnetic 3D Printing of Cellular Structures with MCF-7 Cell Inks
A contactless label-free method using a diamagnetophoretic ink to rapidly print three-dimensional (3D) scaffold-free multicellular structures is described. The inks consist of MCF-7 cells that are suspended in a culture medium to which a paramagnetic salt, diethylenetriaminepentaacetic acid gadolinium (III) dihydrogen salt hydrate (Gd-DTPA), is added. When a magnetic field is applied, the host fluid containing the paramagnetic salt is attracted towards regions of high magnetic field gradient, displacing the ink towards regions with a low gradient. Using this method, 3D structures are printed on ultra-low attachment (ULA) surfaces. On a tissue culture treated (TCT) surface, a 3D printed spheroid coexists with a two-dimensional (2D) cell monolayer, where the composite is termed as a 2.5D structure. The 3D structures can be magnetically printed within 6 hours in a medium containing 25 mM Gd-DTPA. The influence of the paramagnetic salt on MCF-7 cell viability, cell morphology, and ability of cells to adhere to each other to stabilize the printed structures on both ULA and TCT surfaces is investigated. Gene expressions of hypoxia-inducible factor 1-alpha (HIF1α) and vascular endothelial growth factor (VEGF) allow comparison of the relative stresses for the printed 3D and 2.5D cell geometries with those for 3D spheroids formed without magnetic assistance. This magnetic printing method can be potentially scaled to a higher throughput to rapidly print cells into 3D heterogeneous cell structures with variable geometries with repeatable dimensions for applications such as tissue engineering and tumour formation for drug discovery