Experience With Cardiology-Oriented Outcomes in Critically Ill Patients With Coronavirus Disease 2019

OBJECTIVES

Coronavirus disease 2019 is associated with high mortality rates and multiple organ damage. There is increasing evidence that these patients are at risk for various cardiovascular insults; however, there are currently no guidelines for the diagnosis and management of such cardiovascular complications in patients with coronavirus disease 2019. We share data and recommendations from a multidisciplinary team to highlight our institution's clinical experiences and guidelines for managing cardiovascular complications of coronavirus disease 2019.

DESIGN SETTING AND PATIENTS

This was a retrospective cohort study of patients admitted to one of six ICUs dedicated to the care of patients with coronavirus disease 2019 located in three hospitals within one academic medical center in Atlanta, Georgia.

MEASUREMENTS/INTERVENTIONS

Chart review was conducted for sociodemographic, laboratory, and clinical data. Rates of specific cardiovascular complications were assessed, and data were analyzed using a chi-square or Wilcoxon rank-sum test for categorical and continuous variables. Additionally, certain cases are presented to demonstrate the sub committee's recommendations.

MAIN RESULTS

Two-hundred eighty-eight patients were admitted to the ICU with coronavirus disease 2019. Of these, 86 died (29.9%), 242 (84.03%) had troponin elevation, 70 (24.31%) had dysrhythmias, four (1.39%) had ST-elevation myocardial infarction, eight (2.78%) developed cor pulmonale, and 190 (65.97%) with shock. There was increased mortality risk in patients with greater degrees of troponin elevation (p < 0.001) and with the development of arrhythmias (p < 0.001), cor pulmonale (p < 0.001), and shock (p < 0.001).

CONCLUSIONS

While there are guidelines for the diagnosis and management of pulmonary complications of coronavirus disease 2019, there needs to be more information regarding the management of cardiovascular complications as well. These recommendations garnered from the coronavirus disease 2019 cardiology subcommittee from our institution will add to the existing knowledge of these potential cardiovascular insults as well as highlight suggestions for the diagnosis and management of the range of cardiovascular complications of coronavirus disease 2019. Additionally, with the spread of coronavirus disease 2019, our case-based recommendations provide a bedside resource for providers newly caring for patients with coronavirus disease 2019.

Life's Simple 7 Approach to Atrial Fibrillation Prevention

Atrial fibrillation (AF) is the most commonly encountered arrhythmia in clinical practice. It constitutes a major public health problem, with total related annual expenses estimated at $6.65 billion. The American Heart Association developed Life's Simple 7 (LS7) to define and monitor ideal cardiovascular health (CVH). In this review, we examine the role of individual components of LS7 to provide further insight regarding potential influence of achieving AHA's strategic goal on AF prevention. While significant advances have been made in the secondary prevention of AF, little progress has been made to prevent the first occurrence of this arrhythmia in at-risk patients. Improvement of overall cardiovascular health as defined by LS7 may substantially reduce AF risk.

Abstract 321: Cardiometabolic Recovery Kinetics Post Apheresis in a Model of Accelerated Atherothrombosis

Background: Atherothrombotic disease is a chronic, smoldering multifaceted process of inflammatory, lipid, and oxidative insult. Familial hypercholesterolemia (FH) serves as a model of accelerated disease in which these pathways may be better characterized.

Methods: Eight FH patients were assessed before and after LDL apheresis at multiple time points for levels of: Non-esterified fatty acids (NEFA), lipoprotein-associated phospholipase A2 mass (PLAC), thiobarbituric acid reactive substances (TBARS), C-reactive protein (CRP), triglycerides (TG), insulin, and glucose.

Results: Mean pre- and post-apheresis plasma levels were: 2.76 and 1.05 for CRP, 16.64 and 7.11 for insulin, 98.7 and 81.1 for glucose, 156 and 110 for TG, 177 and 97 for PLAC, and 0.5 and 0.72 for NEFA (p < 0.10, all). Plasma glucose, insulin, and TG levels showed concurrent post-prandial peaks at 12 and 36 hours post-apheresis (Fig 1). NEFA peaked during fasting states at 24 and 48 hours post-apheresis (Fig 1). Maximum mean % gain was: 33.7%[(1.98-1.05)/2.76] for CRP from 6 to 12 hours, followed by 24.1%[(0.48-0.35)/0.54] for TBARS and 15.2%[(123.2-96.29)/177.12] for PLAC from 12 to 24 hours.

Conclusion: Our data show that LDL apheresis significantly decreases inflammatory, metabolic and oxidative burden in FH patients. Peaks in glucose, insulin and TG were within normal range arguing against post-prandial dysmetabolism in FH patients. NEFA increased with apheresis and fasting, suggestive of hormone-sensitive lipase upregulation. The temporal progression of recovery shows a predominant inflammatory process acutely, followed by high oxidative stress as a result of PLAC preponderance.

Effects of combination lipid therapy on coronary stenosis progression and clinical cardiovascular events in coronary disease patients with metabolic syndrome: a combined analysis of the Familial Atherosclerosis Treatment Study (FATS), the HDL-Atherosclerosis Treatment Study (HATS), and the Armed Forces Regression Study (AFREGS)

We examined the impact of metabolic syndrome (MS) on coronary stenosis progression and major cardiovascular (CV) events and investigated the mitigating effects of low-density lipoprotein (LDL) cholesterol lowering and LDL cholesterol lowering plus high-density lipoprotein (HDL) cholesterol increasing. This analysis combined individual patient data from 445 subjects who participated in 3 double-blinded, randomized, placebo-controlled trials (FATS, HATS, and AFREGS) comparing intensive lipid therapy to placebos on coronary stenosis progression by quantitative coronary angiography and on major CV events. The primary end points were change in mean proximal coronary diameter stenosis (Delta%S(prox)) over 3 years and the frequency of the predefined composite of coronary artery disease death, nonfatal myocardial infarction, stroke, and revascularization due to worsening ischemia. Patients with MS had 50% more rapid coronary stenosis progression and 64% increased CV event frequency compared to those without. More rapid coronary stenosis progression was significantly and independently associated with a 3.5-fold increased event risk (p <0.001). Combination lipid therapy significantly decreased stenosis progression by 83% (Delta%S(prox) 0.5 vs 2.9, p <0.001) in patients with MS and induced a small net regression in those without (Delta%S(prox) -0.3 vs 2.0, p <0.001). Combination therapy decreased the event rate by 54% (13% vs 28%, p = 0.03) in those with MS and by 82% (3% vs 17%, p = 0.002) without. On average, each 10% decrease in LDL cholesterol or 10% increase in HDL cholesterol was significantly associated with a 0.3 Delta%S(prox) decrease. Each 10% decrease in LDL cholesterol or 10% increase in HDL cholesterol was associated with 11% (p = 0.02) or 22% (p <0.001) event risk decrease. In conclusion, patients with MS have significantly more rapid coronary stenosis progression and a higher frequency of CV events. Greater stenosis progression rate is associated with a higher event rate. LDL cholesterol-lowering and HDL cholesterol-increasing therapies independently and significantly decrease coronary stenosis progression and decrease CV events.

Interactive multimedia preventive alcohol education: a technology application in higher education

This article summarizes the process of implementation and short-term impact on knowledge and attitudes of an interactive multimedia software program on preventive alcohol education for young adults. The three factors related to behavioral change addressed in the software are self-efficacy in maintaining personal control and safety while using alcohol, attitudes and related expectations regarding the physiological and behavioral consequences of alcohol consumption, and peer norms regarding alcohol consumption. As compared to alternative alcohol education and a no-alcohol education groups, students using the interactive computer lesson reported learning more about dose-response and ways to intervene with friends in peril. The article concludes with consideration of the import of this technology for informing students about the consequences of alcohol use, and the utility to higher education institutions of using this technology in an era when pressures increase for due diligence around student safety but with few additional institutional resources.

The effects of family structure and SES on family processes in early adolescence

This study investigates parent-adolescent relationships in early adolescence, focusing on the effects of dyadic communication, family cohesion, family structure, and SES on family conflict in three ethnic groups: African-American (n =1886), Mexican-American (n =2657), and Euro-American (n =3052). Sixth, seventh and eighth grade girls and boys completed questionnaires and results were analysed using independent samples t -tests and multiple regression. Results showed 3-year increases in family conflict in all three ethnic groups. There were significant differences in scale scores on conflict, communication, and family cohesion between nuclear and single-parent families. Some ethnic and gender differences were also found. Discussion focuses on the implications of the findings for family life.

Interdisciplinary health care and female victims of domestic violence

Female victims of domestic violence often face uncertainty in hospital emergency rooms. Victims may encounter physicians, nurses, social workers, and other health care providers who do not work collaboratively, have limited knowledge of domestic violence, and express negative attitudes. Hence, treatment outcomes may be negative. A retrospective case study of 153 medical records of female victims at two Midwestern hospital emergency medicine departments was completed. Findings suggest positive treatment outcome where interdisciplinary collaboration was evident. Included were more accurate assessments in terms of past history, more descriptive emotional symptoms displayed by victims, and written documentation of recommendations concerning intervention and linkage to community resources. Implications for policy and interdisciplinary training are discussed.

Exercised-induced increase in lipid peroxidation parameters in amenorrheic female athletes

OBJECTIVE

To determine plasma lipid peroxidation parameters in eumenorrheic and amenorrheic athletes and to evaluate differences in their response to exercise-induced oxidative stress. In female athletes, intense physical exercise has been shown to be associated with an increased occurrence of menstrual dysfunction with lower levels of E2. Recently, a protective role has been demonstrated for estrogens as free radical scavengers.

DESIGN

Comparison of eumenorrheic and amenorrheic athletes before and after an acute bout of exercise.

SETTING

Academic Research Environment.

PATIENT(S)

Seven eumenorrheic (normally menstruating) and seven amenorrheic (<3 menses/year) female athletes aged 18 to 35 years participating in regular training.

MAIN OUTCOME MEASURE(S)

Plasma and low-density lipoprotein oxidation parameters, plasma E2 and vitamin E levels, and creatine kinase activity.

RESULT(S)

Both the amenorrheic and eumenorrheic athletes demonstrated a significant decrease in the lag time of conjugated diene formation after exercise (P < 0.01), with greater magnitude of change occurring in the amenorrheic athletes (P < 0.05). In addition, postexercise samples from amenorrheic (but not eumenorrhic) athletes showed a significant (P < 0.01) increase in oxysterol formation as compared to baseline values. Amenorrheic athletes also demonstrated a significantly higher baseline creatine kinase activity and a nonsignificant (P = 0.04) trend of an increase in creatine kinase activity after exercise.

CONCLUSION(S)

The results of this study shows that amenorrheic female athletes demonstrate an increased potential for lipid peroxidation after exercise. This could be related to lower plasma E2 levels in this group, considering the strong free radical scavenging ability of estrogens identified recently.

Pharmacokinetic evaluation of high-dose etoposide phosphate after a 2-hour infusion in patients with solid tumors

Etoposide phosphate, a water soluble prodrug of etoposide, was evaluated at levels potentially useful in transplantation settings in patients with malignancies. For pharmacokinetic studies of etoposide phosphate in this phase I study, 21 patients with solid tumors were treated with etoposide phosphate given as etoposide equivalents of 250, 500, 750, 1000 and 1200 mg/m2 infused over 2 h on days 1 and 2, and G-CSF 5 micrograms/kg per day starting on day 3 until WBC was > or = 10,000/microliters. Qualitative, quantitative, and pharmacokinetic analysis was performed as reported previously. Rapid conversion of etoposide phosphate into etoposide by dephosphorylation occurred at all dosage levels without indication of saturation of phosphatases. Plasma levels (C(pmax)) and area under the curve (AUC) of etoposide phosphate and etoposide demonstrated linear dose effects. For etoposide, plasma disposition demonstrated biphasic clearance, with mean T1/2 alpha of 2.09 +/- 0.61 h, and T1/2 beta of 5.83 +/- 1.71 h. An AUC as high as 1768.50 micrograms.h/ml was observed at a dose of 1200 mg/m2. The total body clearance (TBC) showed an overall mean of 15.72 +/- 4.25 ml/min per m2, and mean volume of distribution (VDss) of 5.64 +/- 1.06 l/m2. The mean residual time (MRT) for etoposide was 6.24 +/- 1.61 h. In urine, etoposide but not etoposide phosphate, was identified with large quantitative variations (1.83% to 33.45% of injected etoposide equivalents). These results indicate that etoposide phosphate is converted into etoposide with the linear dose-related C(pmax) and AUCs necessary for use of this agent at the high dosage levels needed in transplantation protocols. A comparison of pharmacokinetic parameters of high-dose etoposide with the values observed in our study with etoposide phosphate revealed comparable values for the clinically important C(pmax) and AUCs, clearance, terminal T1/2 and MRT. In contrast to the use of etoposide, etoposide phosphate can be delivered in aqueous vehicles and therefore may offer the advantage of ease of administration.

Depletion of glutathione from brain cells in hyponatremia

In response to hyponatremia, brain cells extrude electrolytes and organic osmolytes, thereby minimizing brain edema. We demonstrate that rat brain is depleted of the antioxidant glutathione in response to hyponatremia and that osmotically-induced loss of glutathione makes neuronal cells more susceptible to oxidative injury. Total glutathione content of brain tissue decreased from 6.80 +/- 0.14 mumol/g dry wt in normonatremic controls to 5.00 +/- 0.31 mumol/g dry wt after 72 hours of hyponatremia. Following slow correction of hyponatremia, brain glutathione content returned to control values (6.77 +/- 0.34 mumol/g dry wt). Brain content of taurine, a beta-amino acid with antioxidant properties, similarly decreased in hyponatremia (29.6 +/- 0.9 to 17.1 +/- 1.2 mumol/g dry wt), then increased with slow correction (24.8 +/- 1.3 mumol/g dry wt). Although taurine served as an osmolyte in rat heart, liver and brain, osmotically-induced changes in glutathione content were found only in brain. We also studied osmotically-induced changes in glutathione and taurine content in C6 glioma and SK-N-SH neuroblastoma cells. In both cell lines, adaptive decreases in glutathione and taurine content were found in response to lowering medium sodium concentration from 140 mM to 100 mM. The cell content of these solutes increased after returning to media containing 140 mM sodium. Following exposure of both cell lines to hypoosmolar media, there was no increase in media content of glutathione. This suggest that osmotic depletion of glutathione is not due to cellular efflux of intact glutathione. We questioned if osmotic depletion of glutathione and taurine renders brain cells more susceptible to oxidative stress. Incubation of SK-N-SH cells with 1.0 mM H2O2 for four hours induced greater cytolytic injury in cells adapted to hypoosmolar media than in isoosmolar controls. Hypoosmolar C6 glioma cells were not significantly more sensitive to cytolytic injury from H2O2 than were cells grown in isosmolar media. We conclude that hypoosmolality induces glutathione depletion in rat brain in vivo and in cultured brain cells in vitro. Osmotic depletion of this antioxidant renders SK-N-SH neuronal cells more susceptible to oxidative injury.

Dyspnea in dystonia. A functional evaluation

BACKGROUND

Dystonia consists of action-triggered sustained focal muscle contractions, worsened by effort, and resulting in voice changes, abnormal posturing, and dyspnea. The cause of dyspnea, previously unexplained, is the basis of this report.

METHODS

Since the maximal efforts required to perform pulmonary function testing (PFT) could worsen the muscular contractions in dystonic patients, we used several tests to identify possible causes of dyspnea. These included spirometry with flow volume loops (FVL), tidal volume breathing, maximum voluntary ventilation (MVV), and inspiratory and expiratory muscle pressures (PImax, PEmax), sitting and supine. We used cycle ergometry with arterial blood gas (ABG) values to detect cardiac/pulmonary limitations and respiratory inductive plethysmography (RIP) to assess chest wall/abdominal movements for synchrony. Dynamic videofluoroscopy (VF) assessed and recorded the action-triggered muscle activity of the upper airways and the diaphragm during quiet breathing, speech, swallowing, and maximal respiratory maneuvers similar to the efforts required during PFT.

RESULTS

Twenty-six dystonic patients, 12 women and 14 men, ages 14 to 70 years (mean age, 52.3 years) were evaluated. Their neurologic classification included 22 primary (idiopathic) and 4 secondary (2 postneuroleptic use, 2 posstraumatic). Four patients originally classified as having focal dystonia had dyspnea and were found to have diaphragmatic and/or upper airway dysfunction too. The PFTs showed abnormal FVL and/or tidal volume breathing patterns, with intermittent interruptions of air flow during inspiration or expiration in 20 of 24 patients. The VF was abnormal in 24 of 26 patients: 19 patients had combined upper airway (UA) and diaphragmatic dysfunction (DD); 1 patient had UA dysfunction alone, and 4 patients had DD alone. Except for poor effort and/or dystonic movements, cycle ergometry was normal in 18 of 21 patients. The ABG values and/or pulse oximetry were normal in 19 of 22 patients.

CONCLUSION

Dyspnea in dystonia appears to be due to excessive and/or dysynchronized contractions of the upper airways and/or diaphragm, with usually normal gas exchange. These spasmodic and irregular muscular contractions during speech and daily activities are associated with the sensation of excessive effort to overcome the spasms. Excessive spasms can be triggered during PFT and are best detected on FVL patterns coupled with dynamic VF.

MR urography: technique and application

PURPOSE

To evaluate a magnetic resonance (MR) technique for depicting the kidneys and urinary tract.

MATERIALS AND METHODS

Fourteen patients with urinary tract obstruction and 20 without obstructions were examined with a modified, heavily T2-weighted fast spin-echo pulse sequence (MR urography). In addition, six healthy volunteers underwent modified MR urography with intravenous administration of furosemide and ureteral compression prior to imaging.

RESULTS

MR urography provided high-resolution images of the kidneys and urinary tract in all patients with obstruction with intact collecting systems. Anatomic anomalies were depicted in two patients. Intraluminal neoplasia was well demonstrated in both obstructed and nonobstructed systems (n = 4). Furosemide-enhanced MR urography provided fine anatomic and functional detail of both the kidneys and urinary tract (n = 6).

CONCLUSION

MR urography may provide an alternative to more conventional urinary tract imaging techniques. It does not require ionizing radiation or iodinated contrast material. When combined with furosemide and ureteral compression, MR urography provides fine detail and reflects function.

An evaluation of the reliability of Widmark calculations based on breath alcohol measurements

This study evaluated the reliability of Widmark calculations, based on breath ethanol reading (BrACs), for estimating the amount of alcohol consumed. A standard ethanol dose (males 0.51 g/kg; females 0.43 g/kg) was given to 115 college seniors, and BrACs were measured for two hours. Calculations of ethanol dose were performed using BrACs taken at 60, 75, 105, and 125 minutes after drinking. Mean calculated ethanol doses were lower than actual doses at each time point (P < 0.001). Mean underestimates were 13, 12, 15, and 14 mL of 100 proof vodka at 60, 70, 105, and 125 min after drinking. Calculated doses overestimated actual doses in 11, 10, 3, and 3 subjects at 60, 75, 105, and 125 min after drinking. The maximum overestimates were 13, 11, 6, and 8 mL of vodka at 60, 75, 105, and 125 min after drinking. At the 95% confidence level, the calculated dose at 105 and 125 min did not overestimate the true dose, but could underestimate it by as much as 30 mL vodka.

Idiopathic esophageal ulceration in the acquired immunodeficiency syndrome: radiologic reappraisal in 10 patients

Idiopathic esophageal ulceration in patients with AIDS has previously been described. Establishing this diagnosis is important because of the excellent response of these ulcers to corticosteroid therapy. We studied 10 such patients with esophagography and endoscopy. HIV was isolated from the ulcer base in six of the 10 patients utilizing various techniques including in situ hybridization. No other organisms were found. All of the ulcers were in the distal half of the esophagus and were solitary in eight of the 10 patients. The solitary ulcers were large (2.5 x 2.0 cm to 12 x 9 cm) and deep (> 0.5 cm) with undermined margins. In three patients, fistulae arose from the distal esophagus and crossed the gastroesophageal junction. In one patient, a huge idiopathic ulcer perforated into the mediastinum. These latter findings are not seen in the more common ulcerating AIDS esophagitides due to herpes simplex and cytomegalovirus.

Organic osmolytes in acute hyponatremia

The defense of brain volume during hyponatremia cannot be explained by the losses of brain sodium and potassium. We have examined the brain losses of organic osmolytes in rats after 24 h of severe hyponatremia induced by the administration of vasopressin and 5% dextrose in water. Normonatremic controls and animals with intermediate plasma sodium concentration ([Na]) were produced in vasopressin-treated animals by the administration of isocaloric gavages containing varying amounts of NaCl and free water. The animals were killed at 24 h by decapitation, and one brain hemisphere was quickly frozen in liquid nitrogen for organic osmolyte determinations. When compared with controls (plasma [Na] = 139 +/- 1.5 mM), hyponatremic animals (plasma [Na] = 96 +/- 1 mM) had significantly reduced brain contents for sodium, potassium, chloride, glutamate, myo-inositol, N-acetylaspartate, aspartate, creatine, taurine, gamma-aminobutyric acid, and phosphoethanolamine. Plasma [Na] was highly correlated (P < 0.001) with the brain contents for sodium, potassium, and organic osmolytes. Whereas the observed increase in brain water during hyponatremia was only 4.8%, by calculation, brain swelling without brain organic osmolyte losses would have been 11%, an amount that jeopardizes survival.

Interferon-alpha suppresses the capacity of T cells to help antibody production by human B cells

This study was designed to analyze the effect of interferon-alpha (IFN-alpha) on the potential of T cells to help B-cell differentiation in vitro. Human splenic T cells preactivated via the T-cell receptor (TCR)/CD3 complex, as well as murine EL4 thymoma T cells preactivated with phorbol esters, stimulated human B cells via a species cross-reactive physical interaction to differentiate into antibody-producing cells. If the human or murine T cells were activated in the presence of IFN-alpha, normal proliferation and interleukin-2 (IL-2) production occurred, but the cells did not acquire any B-cell helper potential. Therefore, IFN-alpha modulates the B-cell stimulatory potential of T cells by interfering with the T-cell activation process. In contrast, IFN-alpha neither acted on B cells directly nor on already activated T cells, because it did not suppress B-cell differentiation induced by T cells preactivated in the absence of IFN-alpha. IFN-alpha did not induce the production of inhibitory T-cell factor(s), since T cells preactivated in the presence of IFN-alpha did not inhibit the interaction of B cells with T cells optimally preactivated in the absence of IFN-alpha. Taken together the data indicate that IFN-alpha suppresses the potential of T cells to stimulate B-cell differentiation by interfering with the T-cell activation process, but acts neither on B cells directly nor on already activated T cells.

Epitope mapping of Streptococcus mutans SR protein and human IgG cross-reactive determinants, by using recombinant proteins and synthetic peptides

alpha-Hemolytic oral streptococci are known to possess a family of cell surface cross-reactive proteins termed Ag I/II, having a molecular mass of approximately 180 to 210 kDa. These proteins are implicated in bacterial adherence to various oral tissues, and we showed recently that the SR protein, an I/II Ag-related protein, from Streptococcus mutans OMZ 175 serogroup f possesses Ag mimicry with human IgG. In this study, regions of the SR protein encoding the cross-reactive epitope(s) were analyzed by expressing selected restriction fragments from the cloned sr gene. The three SR-derived polypeptides reacted in ELISA with anti-SR rabbit IgG, whereas only the two polypeptides located along the carboxyl-terminal two thirds of the SR protein reacted with anti-human IgG rabbit IgG. In order to locate more precisely the human IgG-cross-reactive region, we synthesized six peptides, on the basis of the recently determined complete nucleotide sequence of the sr gene. Among these peptides, peptide 2, corresponding to the alanine-rich repeating amino-terminal region, peptide 3, located in the three tandem proline-rich regions, and peptide 6, located near the cell wall-spanning region, were the most interesting in term of antigenicity and immunogenicity. Anti-peptide 2, 3, and 6 rabbit IgG reacted with free SR and with cell wall-associated SR. Peptide 1, located near the amino terminus, was poorly immunogenic. Peptides 4 and 5, located in the putative human IgG-cross-reactive region, were immunogenic; however, anti-peptide 4 rabbit IgG reacted only weakly with SR or human IgG, whereas anti-peptide 5 rabbit IgG reacted strongly with SR and human IgG, and peptide 5 was recognized by anti-SR and anti-human IgG rabbit IgG. These results confirm the cell surface accessibility of this epitope and its potential participation in eliciting, in rabbits, anti-SR IgG cross-reactive with human IgG.

Epitope mapping of Streptococcus mutans SR protein and human IgG cross-reactive determinants, by using recombinant proteins and synthetic peptides

alpha-Hemolytic oral streptococci are known to possess a family of cell surface cross-reactive proteins termed Ag I/II, having a molecular mass of approximately 180 to 210 kDa. These proteins are implicated in bacterial adherence to various oral tissues, and we showed recently that the SR protein, an I/II Ag-related protein, from Streptococcus mutans OMZ 175 serogroup f possesses Ag mimicry with human IgG. In this study, regions of the SR protein encoding the cross-reactive epitope(s) were analyzed by expressing selected restriction fragments from the cloned sr gene. The three SR-derived polypeptides reacted in ELISA with anti-SR rabbit IgG, whereas only the two polypeptides located along the carboxyl-terminal two thirds of the SR protein reacted with anti-human IgG rabbit IgG. In order to locate more precisely the human IgG-cross-reactive region, we synthesized six peptides, on the basis of the recently determined complete nucleotide sequence of the sr gene. Among these peptides, peptide 2, corresponding to the alanine-rich repeating amino-terminal region, peptide 3, located in the three tandem proline-rich regions, and peptide 6, located near the cell wall-spanning region, were the most interesting in term of antigenicity and immunogenicity. Anti-peptide 2, 3, and 6 rabbit IgG reacted with free SR and with cell wall-associated SR. Peptide 1, located near the amino terminus, was poorly immunogenic. Peptides 4 and 5, located in the putative human IgG-cross-reactive region, were immunogenic; however, anti-peptide 4 rabbit IgG reacted only weakly with SR or human IgG, whereas anti-peptide 5 rabbit IgG reacted strongly with SR and human IgG, and peptide 5 was recognized by anti-SR and anti-human IgG rabbit IgG. These results confirm the cell surface accessibility of this epitope and its potential participation in eliciting, in rabbits, anti-SR IgG cross-reactive with human IgG.

Behavioral development and maternal care in tufted capuchins (Cebus apella) and squirrel monkeys (Saimiri sciureus) from birth through seven months

Fourteen infant capuchins and eight squirrel monkeys reared by their mothers in captive species-typical social groups were observed from birth through 7 months. Motoric altriciality of the neonatal capuchin relative to the squirrel monkey is a key feature of behavioral differences between the species in the first few months after birth. Infants of the two species differed substantially in age at onset of independent locomotion, the developmental profile of independent activities, and the overall amount and rate of particular social activities. Capuchins displayed a lag of 7 weeks relative to squirrel monkeys in the pattern of increasing time spent alone; lags in other indices of independent activity and exploratory behaviors were also evident, although not as clear-cut. The species also differed substantially in the nature and frequency of social interactions between infants and others. Capuchins, especially later-born infants of multiparous mothers, experienced a more socially interactive infancy than squirrel monkeys. Contrasts in behavioral developmental and infant care in the two species are related to the timing and duration of the weaning process.

Cytotoxicity and activation of CB1954 in a human tumour cell line

CB1954 (5-aziridin-1-yl-2,4-dinitrobenzamide) is a monofunctional alkylating agent, to which Walker 256 cells are very sensitive. These cells express a nitroreductase which reduces CB1954 to a bifunctional crosslinking agent 5-(aziridin-1-yl)-4-hydroxylamino-2-nitrobenzamide. In vitro testing on the human colon line LS174T showed that the differential cytotoxicities between the monofunctional agent (CB1954), and the active species (generated in situ by the addition of NADH and the Walker rat nitroreductase) were smaller than anticipated due to the unexpected toxicity of CB1954 (IC50 value for CB1954 on LS174T cells of 78 microM). The toxicity of the chemically synthesised active form was less than if it had been generated in situ (on LS174T cells). Further experiments showed that NADH was toxic at the levels used to generate the active species (500 microM). Gel filtration and electrophoresis experiments demonstrated that the human colon carcinoma and choriocarcinoma cell lines MAWI and JAR, as well as LS174T express an enzyme of similar molecular weight to that of the 33 kD Walker cell nitroreductase, which is capable of reducing CB1954 to its toxic metabolite, and reducing MTT to its insoluble formazan salt. The expression of this enzyme presumably accounts for the unexpected toxicity of CB1954.

Colonic diverticulitis in young patients with chronic renal failure and transplantation

The association of colonic diverticulitis with chronic renal failure is well known. In those patients with "adult" autosomal dominant polycystic kidney disease, colonic diverticulitis is an especially common complication. We present two young patients (one teenager and one mid-twenties) who developed intra-abdominal abscess several years after renal transplantation. Neither patient had autosomal dominant polycystic disease nor a known history of gastrointestinal problems but both proved to have underlying, previously unsuspected colonic diverticular disease with abscess formation.

Reactogenicity and immunogenicity of the newly developed purified chick embryo cell (PCEC)-rabies vaccine in man

Purified Chick Embryo Cell (PCEC) rabies vaccine was given to 88 healthy adults according to six different vaccination schedules. Local side effects were reported on reactivity forms after 16.4% of PCECV injections, general symptoms were recorded after 15.1% of the 292 doses administered. IgE antibodies specific for chicken proteins determined by the Radio Allergo Sorbens Test (RAST) could not be shown before and after the vaccinations. With no exception, all 88 vaccinees developed high titres of complement-fixing and neutralizing antibodies as determined by the Rapid Fluorescent Focus Inhibition Test and Serum Mouse Neutralization Test. For the first time, induction of serum interferon by PCEC rabies vaccine has been shown in man. In rabies vaccination, PCEC vaccine seems to be as effective as Human Diploid Cell Strain (HDCS) vaccine.

Computed tomography and sonography in small bowel intussusception: a case report

A 23-yr-old patient with a small bowel intussusception as diagnosed by CT and sonography is presented herein. Sonographic features include a soft tissue mass of bowel origin composed of alternating echodense and echolucent rings. Intussusception by CT has a characteristic appearance created by the individual layers of bowel wall, mesenteric fat located on one margin of the bowel wall, and intraluminal contrast. Awareness of these findings are important as both CT and sonography have become a primary imaging modalities.

Microscale syntheses of anti-tumour platinum compounds labelled with 191Pt

Several compounds of platinum have been found to have significant anti-tumour activity and are in various stages of clinical trials. Four such compounds: cis-PtCl2(NH3)2, cis PtCl2(cyclopropylamine)2, cis,trans-PtCl2(OH)2(isopropylamine)2 and cis-Pt(1,1-cyclobutanedicarboxylate) (NH3)2 were synthesised with radioactive platinum-191 as a label for the study of animal organ distribution, patient blood clearance, urinary excretion and renal uptake and clearance. This paper describes the microscale synthesis of these compounds. Purification and quality control procedures are also described.

Blood clearance of radioactively labelled cis-diammine 1,1-cyclobutane dicarboxylate platinum (II) (CBDCA) in cancer patients

The blood and urinary clearances of cis-diammine 1,1-cyclobutane dicarboxylate platinum(II) (CBDCA, JM8) were determined in four patients with malignancy. A 40 muCi iv injection of 191 Pt/193 Pt (3:1)-labelled CBDCA was followed by serial blood and urine sampling to 72 h. The blood clearance was triphasic, mean values for the fast, intermediate, and slow phases being 10.8 min, 2.5 h, and 125 h, respectively. The fraction of activity excreted in the urine within the first 6 h had a mean value of 66.7%, contrasting with 26.4% for cisplatin. There was only a small fraction of CBDCA excreted by the slow phase (1.5%) as against an average of 20% for CHIP and 27% for cisplatin. The early and rapid renal clearance of CBDCA may account for reduced nephrotoxicity.

The effect of a formula diet on preparation of the colon for barium enema examination. Impact on health care and costs

A preliminary study of unselected ambulatory patients having barium enema examinations showed that 31.5% were optimally prepared for evaluation of polypoid mucosal lesions, but 29% had fecal material in the colon that could have obscured the lesions during examination. Although 38 of 42 patients took prescribed cathartics, 84% did not maintain a low-residue diet, as prescribed at this institution. Subsequently, 98 age-matched patients revealed detailed low-residue diet instructions or a formula diet before barium enema examination. Formula preparation resulted in 51% optimal and only 9.5% unacceptable studies compared with 25% optimal and 34% unacceptable examinations in the control group. Caloric intake averaged 700 kcal/day during low-residue diet preparation and was increased almost twofold with formula preparation; improvement was particularly noticeable in the elderly (556 vs 1,286 kcal/day). Prepackaged low-residue defined diets seem acceptable to patients when substituted for a low-residue diet. Bowel cleanliness is greatly enhanced before the barium enema examination, thus improving health care and reducing radiation exposure and costs.

Effects of adenine arabinoside on lymphocytes infected with Epstein-Barr virus

Low concentrations of adenine arabinoside inhibited growth of two Epstein-Barr virus producer cell lines in culture, while not significantly affecting a nonproducer cell line and a B-cell-negative line. These observations were extended to include freshly infected cells. Mitogen-stimulated human umbilical cord blood lymphocytes were unaffected by the drug at concentration levels that inhibited [3H]thymidine incorporation into the DNA of Epstein-Barr virus-stimulated cells. DNA synthesis in Epstein-Barr virus-superinfected Raji cells was also adversely affected by adenine arabinoside. However, these same low concentrations of adenine arabinoside in the triphosphate form produced less effect on DNA synthesis in nuclear systems and DNA polymerase assays than on growth or DNA synthesis in whole cells. Therefore the effects reported here of low concentrations of the drug on whole cells may be only in part related to DNA polymerase inhibition. The work reported here suggests that adenine arabinoside has multiple sites of action in infected cells.

Site of hydrolysis of collagen by hot trichloroacetic acid

When calfskin collagen is treated with trichloroacetic acid at 90 degrees C, it is hydrolyzed to a mixture of peptides, some of which are quite small. Cleavage of collagen by acid seems to occur at bonds between proline (or hydroxyproline) and other amino acids, with only a limited specificity for which amino acid donates its amino group to the susceptible peptide bond.

Rectal and sigmoid involvement secondary to carcinoma of the prostate

Three types of involvement of the rectum and recto-sigmoid by carcinoma of the prostate are reviewed through an analysis of eight cases. A fourth type with subserosal metastatic implant of the proximal sigmoid may occasionally be encountered. The roentgenographic findings are not pathognomonic, but are characteristic of extrinsic involvement of the bowel wall. When clinical symptoms are predominantly related to the bowel, carcinoma of the prostate is usually advanced. All patients presented with bone metastases, uretero-hydronephorsis, lack of function of one kidney, or both bone metastases and urinary tract obstruction. Rectoscopy and biopsy are helpful. However, biopsy specimens often show non-diagnostic features in secondary malignancy. Correct diagnosis is important, since there is a difference in treatment of primary carcinoma and of secondary involvement of the rectum by prostatic carcinoma. A diagnostic challenge exists if the patient is evaluated by barium enema examination for primary bowel symptoms, in particular, large bowel obstruction. At this time intravenous pyelography and bone survey for metastases may not be available to suggest the correct diagnosis. More widespread use of barium enema examinations in the evaluation of advanced carcinoma of the prostate is suggested, since the type of rectal disease shown on barium enema study was not clinically suspected in five of eight patients. The prognosis is usually unfavorable because of advanced carcinoma. Survival often does not exceed several months to one year. However, one of our patients is still well after three years of hormonal therapy.