Left ventricular volume and cardiac output of the canine heart

This paper describes a mathematical model of some of the circulatory properties of the heart, and it is demonstrated how information about the volume of the ventricle can be retrieved from dye dilution curves using the value of the volume flow rate, the time for maximum dye concentration to appear at the sampling site, and the mean transit time of the dye. A nomograph has been developed in order to eliminate the need for mathematical calculations. The validity of the model described is assessed in seven dog experiments by comparing results obtained using the dye dilution technique with results from cineangiocardiographic films taken almost simultaneously of dispersed radiographic contrast fluid. The flow measurements have been checked using a new method employing a suspension of radio-opaque particles.     

Gallstone ileus: An analysis of 20 patients

An analysis of 20 patients with gallstone ileus treated at the University Hospital in Linköping during a 10-year period is presented. The patients had a median age of 75 years and 70% were women. The symptomatology was usually vague and consisted of diffuse abdominal pain, often accompanied by vomiting. The delay before admission to the hospital averaged 4 days. Radiography with both plain abdominal x-rays and a barium meal showed mechanical intestinal obstruction in all but 1 patient and gallstone ileus was diagnosed before laparotomy in 60% of patients. Enterolithotomy was performed in all patients but there was no surgery on the gallbladder and/or the fistula. The frequency of postoperative wound infection was 25%. There was only 1 death, a mortality rate of 5%. It is our opinion that the low mortality was due to early diagnoses, careful preoperative preparation, an operative procedure aiming only at relief of the obstruction, and improved anesthesia and prophylactive short-term antibiotics. The only indication for an elective cholecystectomy is persistent symptoms of gallbladder disease.     

The biological differences between ovarian serous carcinoma and diffuse peritoneal malignant mesothelioma

Recent improvements in immunohistochemistry panels used for differentiating ovarian serous carcinoma/primary peritoneal carcinoma (OC/PPC) from diffuse malignant peritoneal mesothelioma (DMPM) have resulted in improved diagnostic rates for these tumors in both cytological and histological material. However, little is known about the biological characteristics that differentiate these two cancer types. We performed a comparative analysis of cancer-associated molecule expression data for a cohort consisting of up to 270 serous OC/PPC specimens (only peritoneal lesions) and 32 peritoneal MM. The molecules studied were nerve growth factor receptors (p75, p-TrkA), angiogenic factors (VEGF, IL-8, bFGF, heparanase), laminin receptors (the 67-kDa receptor and the alpha 6 integrin subunit), proteases (MMP-2), immune response mediators (HLA-G), and signaling molecules (the MAPK members ERK, JNK, and p38). The methods used were immunohistochemistry, Western blotting, and RT-PCR. DMPM specimens showed significantly higher expression of p75 (P < 0.001), p-TrkA (P < 0.001), and bFGF (P < 0.001), and significantly lower expression of the 67-kDa receptor (P < 0.001), alpha 6 integrin subunit (P = 0.025), VEGF (P < 0.001), IL-8 (P < 0.001), and HLA-G (P = 0.039) compared with OC/PPC. DMPM specimens showed higher activation ratio (phosphorylated/total enzyme ratio) of all three MAPK members (ERK, P = 0.017; JNK, P < 0.001; p38, P = 0.009) compared with OC/PPC. These data document significant differences in the expression of cancer- and metastasis-associated molecules in MM compared with ovarian carcinoma, and suggest that different biological pathways are involved in tumorigenesis and disease progression in these two tumors.     

Mechanical properties of bacterial cellulose and interactions with smooth muscle cells

Tissue engineered blood vessels (TEBV) represent an attractive approach for overcoming reconstructive problems associated with vascular diseases by providing small calibre vascular grafts. The aim of this study has been to evaluate a novel biomaterial, bacterial cellulose (BC), as a potential scaffold for TEBV. The morphology of the BC pellicle grown in static culture was investigated with SEM. Mechanical properties of BC were measured in Krebs solution and compared with the properties of porcine carotid arteries and ePTFE grafts. Attachment, proliferation and ingrowth of human smooth muscle cells (SMC) on the BC were analysed in vitro. The BC pellicle had an asymmetric structure composed of a fine network of nanofibrils similar to a collagen network. The shape of the stress-strain response of BC is reminiscent of the stress-strain response of the carotid artery, most probably due to the similarity in architecture of the nanofibrill networks. SMC adhered to and proliferated on the BC pellicle; an ingrowth of up to 40 microm was seen after 2 weeks of culture. BC exhibit attractive properties for use in future TEBV.     

Communicating alcohol narratives: creating a healthier relationship with alcohol

Alcohol, like mental health, is a neglected topic in public health discussions. However, it should be defined as a priority public health area because the evidence available to support this is very persuasive. Although only half the world's population drinks alcohol, it is the world's third leading cause of ill health and premature death, after low birth weight and unsafe sex, and the world's greatest cause of ill health and premature death among individuals between 25 and 59 years of age. This article aims to outline current global experiences with alcohol policies and suggests how to communicate better evidence-based policy responses to alcohol-related harm using narratives. The text summarizes 6 actions to provide incentives that would favor a healthier relationship with alcohol in contemporary society. Actions include price and availability changes, marketing regulations, changes in the format of drinking places and on the product itself, and actions designed to nudge people at the time of their purchasing decisions. Communicating alcohol narratives to policymakers more successfully will likely require a discourse emphasizing the reduction of heavy drinking occasions and the protection of others from someone else's problematic drinking.     

Measurement of regional blood flow by the 133xenon inhalation method with an on-line computer.

A computer based multidetector system was developed for the measurement of regional cerebral blood flow (rCBF) by the ¹³³Xenon inhalation technique. The computer portion of the system is characterized by on-line data acquisition, rapid data analysis and presentation of results. Special system features include programs which automatically determine end-tidal Xenon concentrations during the saturation and desaturation phases of the flow measurement and which provide for automatic background subtraction, and a special purpose counter-digital multiplexor-computer interface. The system provides convenience in handling acutely ill patients, and assures reproducible positioning for serial measurements. Typical output format and partial results from 150 patient and normal subject measurements are presented.