Hand-held, dynamic indentation system for measuring myocardial transverse stiffness.

Primary muscle abnormalities and/or alterations in regional loading may be critical in myocardial infarct expansion and remodeling, cardiomyopathy progression, and arrhythmia generation. To differentiate muscle abnormalities from loading abnormalities, an estimation of regional wall stress is needed. Researchers have previously relied on geometric models and finite element analysis to estimate wall stress, but these estimations have not been validated. It has been shown that the transverse stiffness (the ratio of indentation stress to indentation strain during transverse indentations) of a cardiac muscle can be used to estimate the myocardial wall stress. The authors designed and tested a hand-held dynamic indentation system that can determine the regional transverse stiffness of an intact heart in as little as 15 milliseconds, allowing multiple estimations of wall stress over a single contraction cycle. The sensor was validated with a finite-element analysis of the indentation process, as well as with direct measurements on isolated heart muscle, and on soft, nonbiologic materials. The validations confirmed that the dynamic indentation system does accurately estimate myocardial wall stress. This regional-wall-stress sensor could help to enhance the understanding of cardiac pathophysiology, guide therapy, and assist surgeons in planning cardiac surgeries.

Cardiac emergencies.

Learning to effectively treat cardiac emergencies is not an easy task. It is my opinion that mastery of material presented herein will ensure minimal competency. Finding practical experiences to help develop the necessary medical skills will require imagination and creativity. The following are offered as possible resources:1. Attend the American Heart Association's basis and advanced life support classes. (CPR training must be repeated at six-month intervals.) 2. Spend several days and/or nights in the emergency room at a local hospital observing (helping with(emergency care. #. Spend time with a mobile coronary care unit if available in your community. 4. Watch and do venipunctures at the local blood bank or donor center. 5. Observe in the intensive care unit at a local hospital. 6. Assist an oral surgeon in preparing intravenous lines and monitor a patient during sedation. 7. Observe administration of oxygen by an anesthesiologist in the operating room at a local hospital.

Studies in fentanyl-supplemented anaesthesia: awareness and effect of naloxone on early post-operative recovery.

Ninety-nine unselected patients were given a standardized general anaesthetic with fentanyl 1.5 microgram . kg-1 every 30 minutes and were randomly divided into three equal groups; Group I patients received naloxone 0.1 mg. Group II naloxone 0.2 mg and Group III naloxone 0.4 mg intravenously at the end of the operation and after the reversal of neuromuscular blockade. After naloxone the level of consciousness lightened and the response to stimulus increased: the changes were significant in all three groups and the actual changes were significantly greater in Groups II and III compared with Group I. In the Recovery Room there was no significant difference among the Groups for shivering, nausea, vomiting or pain. The incidence of operative awareness was one per cent and that of dreaming eight per cent and this was unrelated to naloxone dosage. Patient acceptance was high, seven patients not wanting this type of anaesthesia again due to (a) light premedication (inherent in the study design), two patients; (b) nausea and vomiting, four patients; and (c) slow awakening, one patient.

Scanning electron microscopy of L-929 cells exposed to interferon and reovirus.

L-929 cells were studied under the scanning electron microscope (SEM) in the course of reovirus infection with and without prior interferon treatment. Two major stages in the cytopathic effect (CPE) were identified on the basis of fine surface morphology as revealed by SEM. Uninfected control cells were spindle-shaped with microvilli and numerous filopodia and were firmly attached to the substratum. In stage 1 of CPE, the cells lose filopodia and develop large blebs. Stage 2 is characterized by undulating surface and pits on the nearly spherical cells which are devoid of microvilli and filopodia. At all time intervals observed post infection, interferon-treated reovirus-infected cells showed more advanced CPE than the non-interferon-treated reovirus-infected counterpart controls.

Dose-finding trials of oral oxamniquine in Rhodesia.

Oral oxamniquine at a total dose of 60 mg/kg (given in 4 equal doses morning and evening over 2 days, after food) is an efficient and apparently very safe drug for the treatment of Schistosoma mansoni infections. Lower doses, or shorter schedules of treatment, are less efficient. The drug has little or no effect on S. haematobium infections. Side-effects are mild and infrequent.

Distribution and extent of schistosomiasis in female pelvic organs, with special reference to the genital tract, as determined at autopsy.

PIP: Tissue samples were taken in a series of 64 consecutive autopsies of African women aged 16-70 years. These were block-dissected and studied to determine the frequency of schistosome eggs in tissues of the uterus, and its adnexa, and in the vagina, as well as to determine the numbers of eggs in these tissues. In addition, by histological examination, it was hoped that the frequency and degree of inflammation accompanying the eggs' presence could be learned. 37 of 64 autopsy specimens showed evidence of schistosomiasis. In terms of the mean number of eggs per gram of tissue, the heaviest deposition of eggs was in the bladder. The cervix, uteri, fallopian tubes, and ovaries had eggs to much the same degree, leaving the myometrium and parametrium with the fewest eggs resident. Rectal tissue was relatively clean, surprizingly. Tissues of pelvic organs were positive for schistosome eggs in a total of 37: 33 by digestion technique, 24 by histology, and 20 by both. Inflammatory changes associated with schistosome eggs were found in 12 of 24 infections discovered histologically. Inflammation in the gential tract was only found in 3 cervixes and 2 vaginal walls; in bladders for example, infectious inflammation was seen in 7. Eggs of S. haematobium were identified in 19 of 24 histologically discovered infections. Eggs of S. haematobium were found in all 33 instances identified by the digestion technique, and in 9 of these instances, eggs of S. mansoni were also found. 7 of 9 infections with S. mansoni were of the rectum and 2 were of the bladder.^ieng

Schistosomiasis of the male pelvic organs. Severity of infection as determined by digestion of tissue and histologic methods in 300 cadavers.

PIP: In order to assess the effects of schistosomiasis in the prostate gland, seminal vesicles, and the intraabdominal portion of the vas deferens, we examined these organs at 200 consecutive autopsies of African males. Portions of these organs as well as of the bladder, were digested in KOH; the proportion of eggs of Schistosoma haematobium found in these organs was: seminal vesicles, 54.5%, spermatic duct, 39.9%, and prostate gland, 20.5%. Eggs of Schistosoma mansoni were rarer in these tissues (bladder, 1%; seminal vesicles, 15.5%; spermatic duct, 8%; and prostate gland, 1%). The mean number of S. haematobium eggs/gm of tissue was substantially greater than for S. mansoni. To compare the histologic technique with that of digestion of tissue, we studied a further 100 consecutive autopsies--77% showed evidence of schistosomiasis by 1 or the other method. The bladder was affected in 65%; prostate gland, 21%, seminal vesicle, 70%; and the vas deferens in 42%. The detection of schistosomiasis was almost as good by the traditional histologic as by the digestion technique. Neither method revealed all infections. The frequency and severity of the lesions in these tissues was studied by standard histologic technique: tissues from the last 100 consecutive cases showed definite inflammatory lesions especially in the seminal vesicles, but less than in the prostate gland. In none, however, was the reaction marked. There was good correlation between the mean number of eggs by the histologic and digestion methods, the exception being the prostate gland. No correlation could be shown between the number of eggs and inflammation; only a few eggs may provoke a marked response or the reverse may occur. Eggs were found mainly in the muscle layer of the seminal vesicles, but also in the mucosa and even the lumen. The number of eggs did not vary much with age of infected person; however after age 60 the mean number of eggs in the bladder and seminal vesicles dropped markedly.^ieng