Prolonged infusion of diazoxide in the management of premature labor in the baboon.

The management of premature labor by the prolonged infusion of diazoxide was evaluated in 33 pregnant baboons. The drug was administered intravenously to the mother with an average rate of 0.065 mg/kg/min for 4 hours. Mild to moderate spontaneous labors were significantly inhibited by diazoxide without jeopardizing the fetus. Diazoxide produced a significant increase in maternal heart rate, but its effect on fetal circulation was minimal. Fetal acid-base state and arterial oxygenation remained essentially unchanged throughout the period of observation. Intravenous administration of this drug to the fetuses caused only mild cardiovascular changes irrespective of its preexisting conditions. Thus, a slow intravenous infusion of diazoxide to the mother in a low dosage appears to be of value for inhibiting the uterine activity in early labor, without interfering with the fetal well-being.     

Interim analysis of a prospective,randomized trial of vacuum-assisted closure versus the healthpoint system in the management of pressure ulcers

Twenty-eight patients with 41 full-thickness decubitus ulcers were randomized to compare the Vacuum-Assisted Closure device (VAC) with the Healthpoint System (HP) of wound gel products in promoting ulcer healing. A total of 22 patients with 35 full-thickness ulcers completed the 6-week trial of treatment, during which time 2 patients (10%) in the VAC group (N =20) and 2 patients (13%) in the HP group (N = 15) healed completely. The mean percent reduction in ulcer volume was 42.1% with HP and 51.8% with VAC (p = 0.46). The mean number of PMNs and lymphocytes per high-power field decreased in the VAC group and increased in the HP group (p = 0.13, p = 0.41 respectively). The mean number of capillaries per high-power field was greater in the VAC group (p = 0.75). There were 15 cases of biopsy-proven osteomyelitis underlying the ulcers; three (37.5%) improved with VAC and none improved with HP (p = 0.25). VAC promotes an increased rate of wound healing and favorable histological changes in soft tissue and bone compared with HP.     

Monoclonal antibodies to human amnion

Mouse hybridoma cell lines secreting monoclonal antibodies to human amnion were established. The reactivities of eight of these monoclonal antibodies (GB1, GB3, GB4, GB5, GB6, GB9, GB10 and GB11) on human skin and term extra-embryonic tissues, which included reflected amniochorions, basal plates, placentae, chorionic plates and umbilical cords, are reported. GB1, GB4, GB5, GB6, GB9 and GB11 showed various reactivity patterns on the epithelial cells of amnion, chorion and skin at different stages of differentiation. In addition, GB9 and GB11 showed extracellular reactivities; GB9 detected chorionic villi which were usually surrounded by fibrinoid and GB11 reacted with fibrinoid structures in the placentae and chorion laeve. GB10 recognized connective tissues in fetal mesenchyme and adult dermis. This study demonstrates the expression of many shared antigens between tissues derived from the extra-embryonic ectoderm and adult skin. These monoclonal antibodies will provide useful tools for further investigations of epithelial differentiation and transformation.     

Na+,K+-ATPase and Ca2+-ATPase activities in the cochlear lateral wall following surgical induction of hydrops

Na+,K+-ATPase and Ca2+-ATPase activities have not been studied quantitatively in the cochlea affected by endolymphatic hydrops. The present study was designed to measure quantitatively the Na+,K+-ATPase and Ca2+-ATPase activities in the cochlear lateral wall and the threshold of auditory brainstem response (ABR) for guinea pigs in the early stages (=2 months) of experimentally induced endolymphatic hydrops. A significant negative association was demonstrated between Ca2+-ATPase activity and the change in ABR threshold for hydropic cochleae (P=0.014), but not for control cochleae (P=0.123), although no such significant association was revealed between Na+,K+-ATPase activity and any change in ABR threshold for both hydropic cochleae (P=0.751) and control cochleae (P=0.352). A significant increase in Ca2+-ATPase activity in the cochlear lateral wall was observed for the hydropic ear, in which normal ABR thresholds were maintained, as compared to the control ear. On the contrary, a mild decrease in Ca2+-ATPase activity in the cochlear lateral wall was observed for the hydropic ear, in which ABR thresholds increased significantly. The present findings suggest that alterations of Ca2+-ATPase activity in the cochlear lateral wall may implicate disturbed calcium-homeostasis in the inner ear, resulting in hearing dysfunction in the early stages of experimentally induced endolymphatic hydrops.     

Exploring the effects of psychosocial and acculturation factors on drinking behavior among aboriginal adolescents in Taiwan

The purpose of this study was to examine the effects of psychosocial and acculturation factors on drinking behavior among Taiwanese aboriginal teenagers. Stratified random sampling was used to select six of the 19 aboriginal schools in Taipei, Pingtung, Hualien, and Taitung counties. A total of 495 student subjects were enrolled in the study, including 290 boys and 205 girls, with classification by tribe of 206 Amis, 97 Atayal, 94 Paiwan, 47 Bunun, 19 Rukai, 15 Yami, 10 Puyuma, two Saisiyat, one Tsou, and four unknown. The analysis indicated that the psychosocial and acculturation factors that directly influenced drinking behaviors of aboriginal teenagers were: self-efficacy, drinking behaviors of parents, peer alcohol use, social assimilation, social attitude, and territorial attitude. In this model, peer alcohol use had the most prominent impact on drinking behavior among aboriginal teenagers. The findings suggest that parents' behaviors play a significant role in the development of problematic drinking behavior in the aboriginal teenager through observation and imitation, and also that self-efficacy and the level of acculturation influences drinking behavior in aboriginal teenagers.     

Peritoneal calcification: causes and distinguishing features on CT

OBJECTIVE: We undertook this study to determine the causes of peritoneal calcification seen on CT and to investigate which CT features distinguish benign from malignant peritoneal calcification. MATERIALS AND METHODS: Seventeen patients with peritoneal calcification were identified through retrospective review of reports from 74765 abdominopelvic CT examinations performed during a 7-year period. We determined the cause of peritoneal calcification by examining medical and histopathologic records. Calcification morphology was classified as nodular or sheetlike on the basis of the consensus interpretation by two independent radiologists. The radiologists also recorded the presence or absence of associated soft-tissue components or lymph node calcification. The association between the CT findings and the cause of calcification was assessed using chi-square analysis. RESULTS: Peritoneal calcification was due to peritoneal dialysis (n = 4), prior peritonitis (n = 3), cryptogenic origin (n = 1), or peritoneal spread of ovarian carcinoma (n = 9). Sheet-like calcification was more common in patients with benign calcification (seven of eight patients) than in those with malignant calcification (two of nine patients, p < 0.05). Nodal calcification was seen only in patients with malignant calcification (five of nine patients vs none of eight, p < 0.05). CONCLUSION: Common causes of peritoneal calcification are dialysis, prior peritonitis, or ovarian cancer; sheetlike calcification indicates a benign cause, whereas associated lymph node calcification strongly suggests malignancy.     

Cerebrospinal fluid rhinorrhea after thermometer insertion through the nose

Cerebrospinal fluid (CSF) rhinorrhea is a rare clinical condition. Most leaks either are caused by traumatic head injury or are a complication of surgical procedures on the base of the skull. CSF rhinorrhea from nasal tube placement has been reported previously. We report a case of nasal thermometer placement during anesthesia complicated by a CSF leakage. We reemphasize that any material--including thermometers, nasogastric tubes, and endotracheal tubes--should be directed posteriorly after introduction into the external naris.     

Halothane and propofol modulation of gamma-aminobutyric acidA receptor single-channel currents

Halothane and propofol enhance the activity of the gamma-aminobutyric acid (GABA) system, which is one of the most important systems in the mechanism of anesthesia. To determine whether halothane and propofol enhance GABAergic responses by the same mechanism, we performed single-channel patch-clamp experiments with rat cortical neurons in primary culture. Each of the open-time and closed-time distributions of GABA(A) receptor single channels was expressed by a sum of fast and slow time constants. Neither halothane nor propofol changed the single-channel conductance. Halothane increased the probability of the channel being open via a prolongation of the slow phase of open time, whereas propofol increased the channel open probability via a shortening of the slow phase of closed time. Thus, although both halothane and propofol augmented the channel open probability, thereby causing an increase in charge transfer during inhibitory transmitter action, they acted by different mechanisms.     

Liver fibrosis grade classification with B-mode ultrasound

B-mode images of 20 fresh postsurgical human liver samples were obtained to evaluate ultrasound ability in determining the grade of liver fibrosis. Image features derived from gray level concurrence and nonseparable wavelet transform were extracted to classify fibrosis with a classifier known as the support vector machine. Each liver sample subsequently underwent histologic examination and liver fibrosis was graded from 0 to 5 (i.e., six grades total). The six grades were then combined into two, three, four and six classes. Classifications with the extracted image features by the support vector machine were tested and correlated with histology. The results revealed that the best classification accuracy of two, three, four and six classes were 91%, 85%, 81% and 72%, respectively. Thus, liver fibrosis can be noninvasively characterized with B-mode ultrasound, even though the performance declines as the number of classes increases. The elastic constants of 16 samples out of a total of 20 were also correlated with the image features. The Pearson correlation coefficients indicated that the image features are more strongly correlated with the fibrosis grade than with the elastic constant.