The kinetics of platelet production and destruction in man

Platelets are derived from the cytoplasm of mature marrow megakaryocytes through cytoplasmic demarcation by invaginating plasma membrane and fragmentation of cytoplasmic protrusions into marrow sinusoids. Thereafter, platelets survive in the circulation for about 9 to 10 days. Platelet production is regulated to meet the demands for circulating platelets by means of humoral stimulation. Mean platelet volume, about 10 fl, remains constant over a wide range of survival times and production rates. In normal individuals platelets are produced at a rate of 35 X 10(9)/1/day (or 2.5 X 10(10) fl/kg body wt.) and reflect directly the marrow megakaryocyte cytoplasmic mass. Platelets have important roles in haemostasis, arterial thrombogenesis, wound healing and atherogenesis. Measurements of platelet survival are useful as an in vivo indicator of platelet participation in pathogenesis and pharmacological prevention of these processes. At present platelet survival is most reliably determined by in vitro radiochromium population labelling. 51Cr-platelet disappearance curves require objective unbiased analysis, preferably by non-linear gamma function least squares computer fitting procedures.     

Indications for thoracotomy following penetrating thoracic injury

The treatment of penetrating thoracic injuries has been reviewed in both civilian and military series. Although most surgeons agree that closed that closed thoracostomy drainage is the initial treatment of choice, the timing of early thoracotomy and perhaps cardiorrhaphy upon patients with penetrating thoracic injuries remains controversial. The purpose of this study was to determine which patients will require immediate thoractomy or cardiorrhaphy following penetrating chest injury. Over a two-year period 190 patients with penetrating thoracic injuries were treated. Of 53 patients who required immediate thoracotomy, 31 suffered cardiac wounds. Seventy-nine patients required laparotomy for associated intra-abdominal injuries. The mortality rate was related to exsanguinating hemorrhage or postoperative intra-abdominal sepsis. Cardiopulmonary complications were rare in the absence of intra-abdominal sepsis and could not be attributed to the thoracic injury or thoracotomy. Indications for immediate cardiorrhaphy or thoracotomy are: 1) location of the entrance wound (70% in upper mediastinum); 2) blood pressure on admission less than 90; 3) initial thoracostomy blood loss greater than 800 cc; 4) radiographic evidence of retained hemothorax; and/or 5) clinical evidence of pericardial tamponade.     

Anesthesia for a child with complex I respiratory chain enzyme deficiency

Computed tomography (CT) excretory urography was performed in five adult female dogs after intravenous injection of a bolus of four different doses of water-soluble iodinated contrast medium (100, 200, 400, and 800 mgI/kg). CT images centered over the urinary bladder were performed before injection and 1, 3, 5, 7, 9, 11, 15, 20, 25, 30, 40, 50, and 60 minutes after injection. Opacification of both ureters was evaluated by measuring maximum CT number of individual ureters at each time. Time opacification curves were generated for each dose. Best opacification of the ureters was obtained with 400 and 800 mgI/kg, with a constant peak at 3 minutes and durable opacification for 1 hour. Insufficient opacification was obtained with lower dose of 100 and 200 mgI/kg.     

Biocenotic dynamics of liquid sewage in the process of its biological purification at aeration stations

A study was made of biological purification of sewage at the aeration stations on the quantitative composition of the main indicator microbes--of bacteria of the coliform group and of the fecal coliform bacilli, enterococci, Proteus, and also pathogenic enterobacteria. There was found a difference in the behaviour of different species of Proteus, i.e. reduction in the process of purification in the numbers of Pr. mirabilis, and a sharp elevation of Pr. morganii content. There was noted an insignificant amount of Pr. vulgaris both before and after the biological purification. It was found that dynamics of biocenosis was influenced by air temperature at the time of collection of the samples. A possibility of reproduction of coliform bacilli serving as one of the factors of autopurification of sewage during the biological purification was confirmed.     

Effect of Addition of Chloride Salts on Rancidity of Ground Pork Inoculated with a Moraxella or a Lactobacillus Species

Two experiments were conducted to determine rancidity development in raw-refrigerated ground pork treated with different types and levels of chloride salts. In the first experiment, raw ground pork was inoculated with either a Moraxella or a Lactobacillus species. In the second experiment, samples were not inoculated. In both experiments, samples were treated with either NaCl, KCl, or MgCl₂ at ionic strength of either 0.73 or 0.37 and stored at 5°C. Regardless of inoculation, in both experiments addition of any chloride salt increased (P < 0.05) TBA values over those values for controls (no added salt). Addition of NaCl resulted in the highest (P < 0.05) TBA values among inoculated samples, but these differences were not apparent for noninoculated samples.     

A quantitative structural model of the testis of fertile males with normal sperm counts

The morphology of testicular biopsies of 8 healthy fertile men with proven normal sperm counts was studied using stereological techniques. Quantitative estimations were made of different cellular compartments in the testicular biopsies. The experimental errors of observation, homogeneity of the section, accuracy of the measurements and errors caused during the preparation of the sections were studied. A stereological model of the human testis comprising all compartments was designed. The present observations on the stereological parameters were compared with the results in literature; generally a good agreement was found. This stereological model enabled the authors to establish the quantitative correlations that exist between the separate compartments of the human testis. The tubular length density was positively correlated with the tubular surface density. The tubular surface density showed a negative correlation with the volume density of the germinal cell nuclei. The tubular volume density showed a negative correlation with the volume density of the Leydig cells. The intra-tubular volume density correlated negatively with the volume density of the Leydig cells and with the volume density of the remaining extra-tubular tissue. The intra-tubular tissue density correlated negatively with the volume density of the intra-tubular space.     

Enteroviral persistence in eye infections in monkeys (postuveitis syndrome)

Follow-up (5.5 years) of monkeys with a history of acute enterovirus uveitis (AEU) after intraocular infection with ophthalmotropic ECHO 11 and ECHO 19 strains showed progressive changes in the infected eye; destruction of the iris, formation of films in the anterior chamber of the eye, deformation of the pupil, and signs of cataract and glaucoma. A short (1-30 days) stage of active reproduction of infective virus (up to 10(10) TCD50/g tissue in the first days postinfection) was followed by the second very long stage of limited specific multiplication of virus in ocular tissues. The virus was not detected during the second stage, but its components (virusspecific antigen and crystalloid accumulations of virions) were found in ophthalmic and conjunctival tissues; moreover, high levels of neutralizing antibodies were detected in the blood. The results indicate AEU transformed into a stubborn persistent infection of the eye in monkeys. The findings of this follow-up and published reports about many-year follow-up of children with AEU permit us to classify a post-uveitis disease as a special nosological form of a persistent enterovirus infection and denote it as enterovirus post-uveitis syndrome. The main signs of this syndrome are a history of AEU, progressive destructive changes in the anterior segment of the eye, presence of virus components in ocular tissues in remote periods after infection, and high antibody level in the blood.