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Complex signal transduction pathways underlie the myriad plant responses to attack by pathogens. Ca(2+) is a universal second messenger in eukaryotes that modulates various signal transduction pathways through stimulus-specific changes in its intracellular concentration. Ca(2+)-binding proteins such as calmodulin (CaM) detect Ca(2+) signals and regulate downstream targets as part of a coordinated cellular response to a given stimulus. Here we report the characterization of a tomato gene (APR134) encoding a CaM-related protein that is induced in disease-resistant leaves in response to attack by Pseudomonas syringae pv. tomato. We show that suppression of APR134 gene expression in tomato (Solanum lycopersicum), using virus-induced gene silencing (VIGS), compromises the plant's immune response. We isolated APR134-like genes from Arabidopsis, termed CML42 and CML43, to investigate whether they serve a functionally similar role. Gene expression analysis revealed that CML43 is rapidly induced in disease-resistant Arabidopsis leaves following inoculation with Pseudomonas syringae pv. tomato. Overexpression of CML43 in Arabidopsis accelerated the hypersensitive response. Recombinant APR134, CML42, and CML43 proteins all bind Ca(2+ )in vitro. Collectively, our data support a role for CML43, and APR134 as important mediators of Ca(2+)-dependent signals during the plant immune response to bacterial pathogens.

Background: Some people in states of excited delirium die while in police custody. Emerging evidence suggests that physical restraint in certain positions may contribute to such deaths. In this study the authors determined the frequency of physical restraint among people in a state of excited delirium who died unexpectedly., Methods: The authors reviewed the records of 21 cases of unexpected death in people with excited delirium, which were investigated by the Office of the Chief Coroner for Ontario between 1988 and 1995. Eyewitness testimony, findings during postmortem examinations, clinical history, toxicological data and other official documents describing the events surrounding the deaths were analyzed. Specific reference was made to documented eyewitness testimony of restraint method, body position and use of capsicum oleoresin (pepper) spray. Because cocaine was detected in the blood of some of these people during the postmortem examination, the role of cocaine in excited delirium was examined by comparing the cocaine levels in these cases with levels in 2 control groups: 19 people who died from acute cocaine intoxication and 21 people who had used cocaine shortly before they died but who had died from other causes., Results: In all 21 cases of unexpected death associated with excited delirium, the deaths were associated with restraint (for violent agitation and hyperactivity), with the person either in a prone position (18 people [86%]) or subjected to pressure on the neck (3 [14%]). All of those who died had suddenly lapsed into tranquillity shortly after being restrained. The excited delirium was caused by a psychiatric disorder in 12 people (57%) and by cocaine-induced psychosis in 8 (38%). Eighteen people (86%) were in police custody when they died. Four (19%) had been sprayed with capsicum oleoresin, and heart disease was found in another 4 at autopsy. The blood level of cocaine in those whose excited delirium was cocaine induced was similar to levels found in recreational cocaine users and lower than levels found in people who died from cocaine intoxication., Interpretation: Restraint may contribute to the death of people in states of excited delirium, and further studies to test this hypothesis are recommended. Meanwhile, law enforcement authorities and others should bear in mind the potential for the unexpected death of people in states of excited delirium who are restrained in the prone position or with a neck hold.

Multiple comminuted fractures distributed around a skull and resulting from repeated weapon impacts were poorly demonstrated on conventional lateral and upper frontal radiographs. This was due to superimposition of contralateral fractures, normal anatomy and tangential projection angles. Simple modification of a standard dental x-ray generator and manipulation of projection geometry allowed isolation of individual fractures with improved image quality. The above technique lends itself to cases in which soft tissue remains to obscure the detail of multiple fractures during clinical observation.

The utility and validity of the diatom test for drowning was studied using a retrospective analysis of 771 cases of drowning mostly from Ontario, Canada, over the period 1977 to 1993. In this article (part one), the utility of the test was assessed using an analysis of test outcomes. In the companion article (part two), the validity of the test was assessed by analyzing the relationship between test outcome and characteristics of diatoms in the bone marrow and samples of putative drowning medium. In the present study, freshwater drownings accounted for 738 of the cases and 33 cases were drownings in bathtubs, pools, or toilets. Diatoms were recovered from the femoral bone marrow of 205 cases (28%) of freshwater drowning and four cases (12%) of domestic water drowning. There was a monthly variation in the frequency of positive test outcomes that could not be explained by seasonal differences in the total number of drownings. However, the monthly variation was strongly correlated with the periodic cycle of diatom blooms that occurs in freshwater. Positive diatom tests were characterized by a limited number of distinctive diatom species per case, and a restricted quantity and size range of diatom frustules. These results indicate that the diatom test for drowning will identify approximately one in three victims of freshwater drowning and may be useful in the assessment of deaths occurring in bathtubs. The correlation of the outcome of the diatom test for drowning with diatom blooms provides further evidence for the reliability of the test.

Objective: To determine the number of Southeast Asians in Ontario who died of the sudden unexplained death syndrome in Asian immigrants., Design: Retrospective review., Setting: Ontario., Cases: All deaths reported to the Office of the Chief Coroner for Ontario from 1992 to 1995., Outcome Measures: Age, residence and country of origin of people who died of sudden unexplained death syndrome in Asian immigrants, as defined by standard criteria, autopsy findings and social history of cases., Results: Eight cases of sudden unexplained death in Asian immigrants were reported during the study period. All involved men, and the mean age at death was 34 (standard error of the mean 7) years (range 23 to 44 years). All of the people were residents of metropolitan Toronto. Four were from Vietnam, three from China and one from the Philippines. Seven people lived with family members; the eighth was unemployed and lived alone. Death occurred during sleep or in the waking hours of the morning in six cases; in two of these cases the person's spouse was awakened by loud, laboured breathing. Two men experienced chest pain, and one of them also had sudden-onset dyspnea. There was no prodromal illness in any case. The only consistent autopsy finding was acute nonspecific pulmonary edema and congestion. Analysis of heart weights failed to reveal signs of significant cardiomegaly., Conclusion: Men from Southeast Asia aged 20 to 45 years are at risk of sudden unexplained death, which usually occurs during sleep. No specific factors have been found that could be used to identify people at risk.

The hyoid is the U-shaped bone of the neck that is fractured in one-third of all homicides by strangulation. On this basis, postmortem detection of hyoid fracture is relevant to the diagnosis of strangulation. However, since many cases lack a hyoid fracture, the absence of this finding does not exclude strangulation as a cause of death. The reasons why some hyoids fracture and others do not may relate to the nature and magnitude of force applied to the neck, age of the victim, nature of the instrument (ligature or hands) used to strangle, and intrinsic anatomic features of the hyoid bone. We compared the case profiles and xeroradiographic appearance of the hyoids of 20 victims of homicidal strangulation with and without hyoid fracture (n = 10, each). The fractured hyoids occurred in older victims of strangulation (39 +/- 14 years) when compared to the victims with unfractured hyoids (30 +/- 10 years). The age-dependency of hyoid fracture correlated with the degree of ossification or fusion of the hyoid synchondroses. The hyoid was fused in older victims of strangulation (41 +/- 12 years) whereas the unfused hyoids were found in the younger victims (28 +/- 10 years). In addition, the hyoid bone was ossified or fused in 70% of all fractured hyoids, but, only 30% of the unfractured hyoids were fused. The shape of the hyoid bone was also found to differentiate fractured and unfractured hyoids. Fractured hyoids were longer in the anterior-posterior plane and were more steeply sloping when compared with unfractured hyoids. These data indicate that hyoids of strangulation victims, with and without fracture, are distinguished by various indices of shape and rigidity. On this basis, it may be possible to explain why some victims of strangulation do not have fractured hyoid bones.

The location of 19 fractures of 15 hyoid bones was studied from 13 cases of manual strangulation and two cases of hanging. The precise location of the fractures were determined by xeroradiography of isolated hyoid bones. To classify the location of the fractures, the greater cornu was divided into anterior, middle, and posterior thirds and the frequency of fracture occurrence in these locations was determined. In addition, the angle of curvature of the greater cornu was determined at the fracture site to ascertain if specific points along the greater cornu were more susceptible to fracture. Fractures were found with equal frequency in the posterior and middle thirds of the hyoid greater cornu (9/19, 47% for both posterior and middle) but were rare in the anterior portion (1/19, 5%). However, all fractures occurred between 30 degrees and 60 degrees of curvature of the hyoid and most fractures (approximately 60%) were found at approximately 50 degrees. These results indicate that fractures of the hyoid occur at vulnerable angles of curvature of the hyoid bone which, due to anatomic variation in hyoid shape, do not necessarily occur at specific segments of the hyoid bone. On this basis, although the presence of the hyoid fracture in strangulation is determined by the rigidity of the bone, the specific location is determined by the shape of the greater cornu.

Identification of evidence indicative of sexual assault, including elevated levels of acid phosphatase (AP) in the vagina, is an important part of the investigation of female homicidal deaths. In this study, vaginal AP levels in 43 female homicide victims, determined using sodium thymolphthalein as the substrate, were retrospectively correlated with semiquantitative assessment of spermatozoa in vaginal smears. The results were then compared with those from a prospectively studied age-matched group of controls. AP determinations ranged from 0 to 6,000 units (U)/L in the homicide group and from 1 to 726 U/L in the control group. In both groups, the majority of the AP values (homicide, 65%; and controls 85%) were < 100 U/L. Spermatozoa were identified on vaginal smears from 30% of the homicide victims and 17% of the controls. The spermatozoa-positive cases had AP levels that ranged from 2 to 6,000 U/L. In both groups, an AP value of > or = 400 U/L was always associated with the presence of spermatozoa on the vaginal smear. Intermediate AP values (100-399 U/L) were associated with the presence of spermatozoa in 60% of the control group and 22% of the homicide group; 18% of the homicide group and 3% of the control group were positive for spermatozoa despite AP values of < 100 U/L. In the absence of spermatozoa on a vaginal smear, an AP value of > 400 U/L strongly suggests the presence of semen that is either oligo- or aspermic. A low or intermediate AP determination, however, does not exclude the presence of semen and hence a careful search for spermatozoa on the vaginal smear is indicated, regardless of the AP value obtained.

The use of Histoacryl glue in the performance of microvascular anastomosis was examined in a rat model. An improvement in efficiency as noted by the decreased ischemic time and diminished bleeding with clamp removal was noted. Histological examination of the anastomosis at one and three weeks revealed a mild foreign body type inflammatory response to glue and suture material with no media necrosis and only minimal fibrointimal proliferation.

Focal nodular hyperplasia (FNH) is a lesion of the liver in which a large anomalous artery is located within a region of hyperplastic hepatic parenchyma. Patients with FNH commonly have other lesions, often vascular in nature, in the liver or other organs. We have noted that these associated lesions almost always occur in patients with multiple FNH. We therefore studied 27 autopsied patients with FNH. All 13 with multiple FNH had other lesions such as hemangioma of liver, meningioma, astrocytoma, telangiectasis of the brain, berry aneurysm, dysplastic systemic arteries, and portal vein atresia. One patient had several of these lesions including multiple FNH, meningioma, astrocytoma, vascular malformation of the brain stem, and hemangioma of the liver. In contrast, among the 14 patients with solitary FNH there were no associated lesions, except for hepatic hemangioma in one patient. The prevalence of this syndrome was estimated by examination of 2500 serial autopsies and autopsies with various components of the syndrome. On review of 73 consecutive autopsies with meningioma, three had multiple FNH, compared with seven of 2500 consecutive adult autopsies (P less than 0.001). Multiple FNH was found in two of 83 autopsies with astrocytoma (P less than 0.05) and in one of 139 autopsies with berry aneurysm (not significant). We describe a telangiectatic subtype of FNH which occurs in this syndrome as well as in a minority of patients with solitary FNH. The existence and character of this syndrome suggest that there may be an underlying systemic abnormality in some patients having components of the syndrome. Investigation of patients with multiple FNH lesions may reveal significant treatable lesions.

A 61-year-old woman with symptoms of inferior vena caval obstruction was investigated with computed tomography and ultrasound imaging and found to have a tumor of the inferior vena cava. Transvenous biopsy revealed a leiomyosarcoma, which at surgical exploration was considered to be unresectable. Autopsy showed that the tumor extended form its origin in the inferior vena cava just above the left renal vein to the right atrium. Hepatic metastases were documented. This rare tumor has seldom been diagnosed prior to exploratory surgery or necropsy and should be included in the differential diagnosis of inferior vena caval obstruction. The case illustrates the relative ease and efficacy of transvenous biopsy in establishing this diagnosis antemortem.

A case of fetal hepatic hemangioendothelioma with secondary nonimmune hydrops fetalis is presented. The prenatal diagnosis, made at 27 weeks' gestation by real-time ultrasonography and pulsed Doppler ultrasound, was confirmed by angiography and pulsed Doppler ultrasound, was confirmed by angiography and autopsy after the infant was born 2 weeks later. To the best of our knowledge, this is the first report of prenatal diagnosis of such an entity.

The authors report the case of a 23-year-old man with a giant-cell tumor of the right middle cranial fossa floor. His presentation and management are described, and some aspects of this rare neoplasm of the skull base are reviewed. The role of adjuvant radiotherapy is discussed.