Angiotensin II induces circadian gene expression of clock genes in cultured vascular smooth muscle cells

BACKGROUND

Daily rhythms of mammalian physiology and endocrinology are regulated by circadian pacemakers. The master circadian pacemaker resides in the suprachiasmatic nucleus, which is located in the hypothalamus of the brain, but circadian oscillators also exist in peripheral tissues. Because many studies have demonstrated apparent circadian variations in the frequency of cardiovascular disorders, it is of great interest to investigate a possible relation between circadian gene expression and cardiovascular function. We examined whether a circadian oscillation system exists in the aorta and/or in cultured vascular smooth muscle cells (VSMCs).

METHODS AND RESULTS

The mRNA levels of clock genes were assayed by northern blot analysis. The mouse aorta showed a clear circadian oscillation in the expression of mPer2, dbp, and Bmal1. Brief treatment of VSMCs with angiotensin II induced a robust increase in mPer2 gene expression, followed by a marked reduction in mPer2 mRNA levels and subsequent synchronous cycling of mPer2, dbp, and Bmal1 mRNAs. The induction of mPer2 in VSMCs by angiotensin II was completely abolished by treatment with CV11947, a specific angiotensin II type1 receptor antagonist.

CONCLUSIONS

The present results demonstrate that the aorta and VSMCs possess a circadian oscillation system which is comparable to that of the suprachiasmatic nucleus and that the circadian gene expression in VSMCs is induced by angiotensin II through the angiotensin II type1 receptor. Our in vitro system will provide a useful tool to further analyze the physiological significance of the peripheral clock in cardiovascular function.

Psychoactive drug use among practicing physicians and medical students

We surveyed random samples of 500 practicing physicians and 504 medical students in a New England state during 1984-1985; 70 percent of the physicians and 79 percent of the students responded. Fifty-nine percent of the physicians and 78 percent of the students reported that they had used psychoactive drugs at some time in their lives. In both groups, recreational use most often involved marijuana and cocaine, and self-treatment most often involved tranquilizers and opiates. In the previous year, 25 percent of the physicians had treated themselves with a psychoactive drug, and 10 percent had used one recreationally. Although most of the use was experimental or infrequent, 10 percent of the physicians reported current regular drug use (once a month or more often) and 3 percent had histories of drug dependence. More physicians and medical students had used psychoactive drugs at some time than had comparable samples of pharmacists and pharmacy students. The results suggest a need for renewed professional education about the risks of drug misuse.

Liver packing for uncontrolled hemorrhage: a reappraisal

The efficacy of liver packing for uncontrolled hemorrhage was assessed in 345 patients with hepatic injuries divided into two groups: Group I (1977-1980; n = 177), when packing was not used and Group II (1981-1985; n = 168) when the technique was employed. Despite similar clinical details, mortality from bleeding was unchanged (19.2% and 19.4% overall, and 63.7% and 61.7% for Grade IV, V, VI liver injuries). Packing was used in 14 patients who were in clinical coagulopathy after debridement-resection of the injured liver: eight patients (57%) expired from continued bleeding; five of the six survivors (83.3%) developed intra-abdominal abscesses despite early removal of the pack. The incidence of sepsis was significantly (p less than 0.002) increased as compared to that of 15 similar patients who had debridement-resection without packing. Liver packing, in our experience, has not altered the mortality from major hepatic trauma and appeared to increase the incidence of abdominal sepsis.

Alcohol use and abuse in random samples of physicians and medical students

BACKGROUND

This study sought to resolve conflicting views about whether physicians are especially prone to alcohol abuse.

METHODS

Using an anonymous, mailed questionnaire on substance use, we surveyed 500 physicians, 510 pharmacists, and 974 of their students. The physicians and pharmacists were selected randomly from the state society's membership lists, and students selected were from local school lists. Follow-up surveys were sent to nonresponders at two-week intervals.

RESULTS

The physicians and medical students did not drink especially heavily and were no more vulnerable to alcoholism than were their counterparts in pharmacy and other professions. Physicians differed from pharmacists in their style of drinking (greater frequency, smaller quantity), but not in total amount of alcohol consumed. Drinking habits among physicians were not associated with medical specialty or type of practice, but were positively related to gender (males drank more than females) and to age (older doctors were more apt to qualify as heavy drinkers than were younger doctors).

CONCLUSIONS

Physicians were no more likely to abuse substances nonmedically than were other professionals. Any group in which alcohol use is nearly universal incurs a risk of abuse and impairment that cannot be ignored.

Penetrating duodenal injuries. Analysis of 100 consecutive cases

One hundred consecutive patients with penetrating duodenal injuries were reviewed retrospectively to analyze the results of various methods of treatment. The severity of the abdominal injury was quantified by the Penetrating Abdominal Trauma Index (PATI). The overall mortality was 25%. Sixteen per cent of the deaths were related to extensive associated organ injury, eight per cent to sepsis, and one per cent to concurrent head trauma. Duodenal fistulas occurred in four per cent and were associated with mortality in two per cent. The complications of duodenal fistula, abdominal sepsis, and mortality from sepsis were significantly higher in those patients treated by repair and decompressive enterostomy with or without a serosal patch than in those with repair or resection. The severity of duodenal and associated organ injuries, as well as the clinical status, were similar in both groups. It is concluded that the majority of duodenal injuries from penetrating trauma may be treated effectively by primary repair, and that the use of decompressive enterostomy or serosal patch appears to contribute to an increased morbidity rate.

Emergency room thoracotomy for the resuscitation of patients with "fatal" penetrating injuries of the heart

A total of 75 patients with penetrating cardiac injuries were treated at Lincoln Medical and Mental Health Center from January, 1974, to November, 1980. Twenty-two patients (29.3%) were unconscious on arrival and had no detectable vital signs, cardiac activity, or spontaneous respirations. Their last physical movement was observed in the ambulance. Immediate resuscitation of these patients employing intercostal or sternal splitting incisions in the emergency room revealed arrested hearts and permitted relief of tamponade, finger occlusion of the cardiac wound or wounds, and temporary suturing of the defect. Restoration of cardiac function was accomplished in 16 patients (72.7%). After transfer to the operating room for more definitive cardiorrhaphy and repair of other major wounds, 8 patients (36.4%) recovered without objective neurological disability. Our experience clearly supports the value of immediate emergency room thoracotomy in this group of patients.

The morbidity of injuries of the extra-hepatic biliary system

Blunt and penetrating injuries of the extrahepatic biliary system are rare and appear to be increasing in frequency. The severe morbidity associated with these lesions is related to incomplete efforts at diagnosis and errors in therapeutic decisions. The morbidity may be minimized by a high index of suspicion and awareness of these lesions; complete exploration of all hematomas around the bile ducts to reduce the incidence of overlooked injuries; meticulous repair of tangential injuries; and primary biliary-enteric diversion for complete transection of the ducts. A knowledge of the various options in operative management is crucial since unexpected injuries are not uncommon.

Emergency room thoracotomy for penetrating cardiac injuries

The results of emergency room thoracotomy (ERT) and cardiorrhaphy for 91 patients with penetrating cardiac injuries admitted in extremis to Lincoln Medical and Mental Health Center from 1963 to 1981 are reviewed to determine criteria for selection of patients for this procedure. Four groups were defined based on the severity of the effects of their injuries. The survival rates were 32.1 and 33.3%, respectively, for Group I ('fatal') and Group II ('agonal') patients. There were no survivors in Group IV ('D.O.A.') patients for whom ERT is a fruitless procedure. Survival in Group III ('profound shock') patients was only 40%, which might have been improved if ERT had been performed without delay. We conclude that ERT is essential for patients with 'fatal' and 'agonal' wounds and advise prompt ERT for patients in 'profound shock' who do not respond immediately to rapid volume infusion.

Pneumatocele formation in adult pneumonia

Pneumatocele formation is unusual in adult pneumonia, particularly in pneumococcal pneumonia. We report three cases of pneumatocele formation in adults, including one with probable pneumococcal pneumonia. All three patients were severely ill and two expired. Although they are usually asymptomatic, pneumatoceles may enlarge and compress the adjacent lung and mediastinum. This occurred in two patients causing respiratory insufficiency and cardiovascular compromise. The placement of a chest tube into the enlarging pneumatocele resulted in successful decompression.

Open management of the septic abdomen: therapeutic and prognostic considerations based on APACHE II

We analyzed the results of open treatment in 30 patients with abdominal sepsis (11 patients after trauma [group 1], five patients with pancreatic abscess [group 2], and 14 patients with acute GI pathology [group 3]) uncontrolled by conventional methods as evidenced by continuing fever with leukocytosis and worsening organ functions. APACHE scores at the time of initial laparotomy and at the time of open management, respectively, were: group 1, 19.8 and 16.6; group 2, 8.4 and 12.4; and group 3, 14.2 and 15.0. Twenty-seven patients had multiple system failure. Sixteen (53%) of the 30 patients survived, 73% in group 1, 60% in group 2, and 36% in group 3. Survival correlated well with age less than 50 yr and the absence of multiple organ failure. The technique was easily performed and many of the pitfalls previously reported were not observed. In patients requiring fascial prosthesis, the absorbable polyglycol acid (Dexon) mesh was found to be superior to the nonabsorbable polypropylene. We conclude that the open technique is feasible, effective, and worthy of consideration in patients with extensive wound necrosis and uncontrolled abdominal sepsis.

Penetrating cardiac trauma. Quantifying the severity of anatomic and physiologic injury

A method of quantifying the anatomic extent of injury to the heart, Penetrating Cardiac Trauma Index, (PCTI) and other thoracic organs has been proposed. The total extent of thoracic injury, Penetrating Thoracic Trauma Index (PTTI), was measured. When associated abdominal injury was present, it was assessed by the Penetrating Abdominal Trauma Index (PATI) of Moore et al. The severity of total injury sustained by the patient, represented by the Penetrating Trauma Index (PTI), was determined by the sum total of these scores. The extent of physiologic abnormality induced by cardiac penetration, (Physiologic Index or PI), was graded on a scale of increasing severity from 5-20 based on the vital signs of patients on admission. Analysis of 112 patients with penetrating cardiac injuries (1973-1983) revealed that the indices, PCTI and PI, showed an excellent correlation with survival (R2 = 0.827 and 0.928, respectively) as did the total extent of trauma (PTI). A composite prognostic score of the sum of PI and PTI demonstrated a significant separation of survivors from nonsurvivors (p less than 0.001). It is concluded that these anatomic (PCTI and PTI) and physiologic (PI) indices are valid and, with additional confirmation, may provide an objective method of evaluating penetrating cardiac injuries.

Future caregivers' views on alcoholism treatment. A poor prognosis

Few students preparing for careers in medicine, nursing, social work, or counseling are interested in devoting their professional time to the care of problem drinkers; this reluctance to become involved in the treatment of alcohol problems is related to prognostic pessimism and negative assessments of existing therapeutic resources for alcoholism treatment.

Separation of copurifying GroEL from glutathione-S-transferase fusion proteins

The purification of overexpressed fusion proteins using bacterial expression systems is a useful tool for the study of many proteins. One problem that can occur is the formation of stable interactions between the expressed fusion protein and certain endogenous bacterial proteins, such as the molecular chaperone GroEL. Such interactions may result in the copurification of contaminating bacterial proteins. Here we describe an efficient and inexpensive method for the removal of contaminating GroEL from a bacterially expressed GST fusion protein. In this method, denatured bacterial proteins are added to the bacterial lysates prior to the addition of glutathione Sepharose resin. The denatured proteins compete for GroEL binding, thereby releasing the GroEL contaminants from the expressed fusion protein.

The structural context of college drinking

The drinking settings and companions of college students were studied in relation to the students' gender, year in school, academic standing, work status and residence status. The relationship between year in school and the quantity and frequency of consumption of specific types of alcoholic beverages was also studied.

Effect of the disease-causing mutations identified in human ribonuclease (RNase) H2 on the activities and stabilities of yeast RNase H2 and archaeal RNase HII

Eukaryotic ribonuclease (RNase) H2 consists of one catalytic and two accessory subunits. Several single mutations in any one of these subunits of human RNase H2 cause Aicardi-Goutières syndrome. To examine whether these mutations affect the complex stability and activity of RNase H2, three mutant proteins of His-tagged Saccharomyces cerevisiae RNase H2 (Sc-RNase H2*) were constructed. Sc-G42S*, Sc-L52R*, and Sc-K46W* contain single mutations in Sc-Rnh2Ap*, Sc-Rnh2Bp*, and Sc-Rnh2Cp*, respectively. The genes encoding the three subunits were coexpressed in Escherichia coli, and Sc-RNase H2* and its derivatives were purified in a heterotrimeric form. All of these mutant proteins exhibited enzymatic activity. However, only the enzymatic activity of Sc-G42S* was greatly reduced compared to that of the wild-type protein. Gly42 is conserved as Gly10 in Thermococcus kodakareansis RNase HII. To analyze the role of this residue, four mutant proteins, Tk-G10S, Tk-G10A, Tk-G10L, and Tk-G10P, were constructed. All mutant proteins were less stable than the wild-type protein by 2.9-7.6 degrees C in T(m). A comparison of their enzymatic activities, substrate binding affinities, and CD spectra suggests that the introduction of a bulky side chain into this position induces a local conformational change, which is unfavorable for both activity and substrate binding. These results indicate that Gly10 is required to make the protein fully active and stable.

Evaluation of subxiphoid pericardial window used in the detection of occult cardiac injury

We critically evaluated several diagnostic modalities (clinical criteria, subxiphoid pericardial window (SPW) and laparoscopy) used in the detection of occult cardiac injury in haemodynamically stable patients at high risk of cardiac injury. Over 5 years, 122 patients were admitted to a Level I trauma centre with such an injury. They sustained 69 stab wounds, and 53 gunshot wounds. Sites of penetration were: precordial (81), right chest (25), lateral chest (13), thoracoabdominal (40) and abdominal (19). Vital signs in the emergency room were (mean +/- SD): systolic BP, 111 +/- 23.2 mmHg; HR, 106 +/- 18.7; GCS, 13.6 +/- 1.3; and CVP, 17 +/- 7.8 cmH2O. SPW was performed in all patients and was positive for haemopericardium in 26 patients, 24 (92 per cent) of whom had a cardiac injury at operation. Two patients had pericardial lacerations without cardiac injury. In addition, 14 patients with lower precordial and thoracoabdominal wounds underwent laparoscopy. At laparoscopy, the pericardium was evaluated by transdiaphragmatic inspection in 10 patients. The presence (two) or absence (eight) of blood within the pericardium was accurately predicted and verified by SPW. Univariate and multiple logistic regression analysis of clinical data failed to reveal any significant predictor of cardiac injury. SPW remains the standard means of diagnosing occult cardiac injury in high-risk patients. Since the incidence of occult cardiac injury in haemodynamically stable patients is 20 per cent, SPW should be used liberally. Laparoscopy may have a role in evaluating the pericardium in the subgroup of patients with lower chest wounds, and it facilitates inspection of intra-abdominal viscera and diaphragm at the same time.

Emergency department thoracotomy for penetrating injuries: predictive value of patient classification

In 18 months, 44 patients underwent thoracotomy in an emergency department (ED) for penetrating thoracic injuries. Of 14 patients resuscitated, seven (50%) survived, and all were neurologically intact. Patients were classified according to the quality of signs of life in transit or upon arrival at the ED. Identical survival rates of 29% were noted for patients in Group I (profound shock) and in Group II (agonal), with survival at 14% for individuals in Group III ("dead" on arrival). There were no survivors among patients in Group IV ("dead" on the scene), and ED thoracotomy, in the authors' opinion, is fruitless in this group. In Groups I, II, and III, total salvage from cardiac injuries was six of 24 patients (25%), and for those with non-cardiac injuries, it was one of 11 (9%). The rate of survival from cardiac stab wounds in Groups I, II, and III, was five of 16 (31%) and one of eight (13%) for gunshot wounds. Five of the seven survivors (71%) arrived at the ED by rapid transport without the benefit of any pre-hospital life support. Patient classification appears to be a valuable tool in evaluating the benefit of ED thoracotomy. The neurological status of all survivors and pertinent transportation data should be included in all future studies of ED thoracotomy. "Scoop and run" in the urban setting with rapid transport capability may be superior to pre-hospital stabilization of victims of penetrating thoracic trauma.

Portal vein injuries. Noninvasive follow-up of venorrhaphy

The authors report their experience with 14 patients with portal vein injuries (1976-1986) treated at a level I trauma center. Seven patients (50%) survived and included six of 10 patients (60%) who had venorrhaphy and one in whom the portal vein was ligated. Associated injuries were present in all the patients (mean Abdominal Trauma Index: 39.5) and accounted for the high mortality rate. Follow-up data after repair or ligation of the portal vein seldom are reported in the literature. The authors studied all three patients who survived portal venorrhaphy since 1982 by real-time ultrasonography. Patency of the repair could be established in two patients. In the third patient postvenorrhaphy thrombosis was diagnosed by ultrasonographic examination. Sequential ultrasonographic examinations demonstrated resolution of the thrombus on anticoagulant therapy. Ultrasonography provides a noninvasive and easily reproducible method of studying the portal vein after repair.

Alcohol, substance use, and other risk-factors of impairment in a sample of physicians-in-training

This article examines survey data on alcohol and drug use, stress and other risk factors of impairment in nonclinical samples of physicians and medical students. Previously unpublished data on a sample of physicians-in-training showed they were healthy nonsmokers, experiencing many feelings of job stress, but were generally light drinkers and suffered few adverse effects of drinking. Young physicians and medical students were not very different from comparable non-physician populations in their use of recreational and therapeutic drugs, although the medical professionals had slightly below average use rates. Regression analyses found that recreational drug use and drinking stemmed mainly from sensation seeking, whereas therapeutic drug use was stress-related.

Risk factors of drug impairment in random samples of physicians and medical students

The prevalence of hypothesized risk factors of drug impairment is estimated and correlated with drug use in random samples of physicians and medical students. Substantial percentages of both physicians and medical students reported access to drugs, family histories of substance abuse, stress at work and home, emotional problems, and sensation seeking. Each of these factors correlated with drug use in physicians or medical students, and analysis suggested that in most cases the hypothesized risk factors were more likely to be causes rather than consequences of drug use.

Post-traumatic thoracobiliary fistula

Post-traumatic thoracobiliary fistulas are preventable complications of thoracoabdominal trauma. Once established, prompt diagnosis and early surgical intervention with chest drainage after decortication, suture repair of the diaphragmatic lacerations, and extraperitoneal liver drainage are crucial in the management of this complication.