Medicare fraud and abuse: implications for physicians

Since the inception of the Prospective Payment System, the physician fee freeze, and other cost-cutting measures, physicians have been approached with many income-generating opportunities relating to their practices. Unfortunately, many of these opportunities also present potential criminal and civil liability under federal Medicare anti-fraud and abuse provisions. The recent passage of the Medicare and Medicaid Program Patient Protection Act of 1987 has updated federal anti-fraud and abuse laws and expanded the sanctions which may be imposed on physicians. This article describes the types of activities prohibited by federal laws and discusses the operation of these laws in light of common joint venture, incentive, and contract arrangements frequently seen in medical practice.

Symposium on age-related macular degeneration

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Analysis of the assembly of laminin and the laminin-entactin complex with laminin chain specific monoclonal and polyclonal antibodies

Antibodies specific for the A, B1, and B2 chains of laminin have been obtained and characterized. Lam V, a rat X mouse monoclonal antibody, was obtained by immunizing Lewis rats with the extracellular matrix derived from the mouse endodermal line M1536-B3. The antibody was shown to recognize a conformation-sensitive epitope present on the A chain of laminin. The antibody exhibited high avidity for native laminin and uncomplexed newly synthesized laminin A chains. cDNA clones in the vector lambda-gt11 containing sequences for the B1 and B2 chains of laminin were shown to synthesize beta-galactosidase fusion proteins in the host cells induced with IPTG. The fusion protein F3 contained amino acid residues 822-1765 of the B1 chain of mouse laminin, and the fusion protein E4 contained 219 amino acids at the carboxyl terminus of the B2 chain of rat laminin. These two fusion proteins were used to obtain rabbit polyclonal antibodies which were characterized for their specificity and ability to immunoprecipitate laminin and the B chains of laminin. The chain-specific antibodies were used to analyze the assembly and processing of laminin in the mouse endodermal cell line M1536-B3. The results indicated that the covalent assembly of the A and B chains of laminin was initiated as early as 3 min after labeling cells. At this time point uncomplexed A chain of laminin could be observed even though there was an excess of B1 and B2 chains. As early as 4 min after labeling monomeric, dimeric, and oligomeric forms of the B chains of laminin were observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Injuries related to all-terrain vehicular accidents: a closer look at head and neck trauma

Morbidity and mortality associated with all-terrain vehicular accidents is climbing at a steady rate. These accidents frequently result in multiorgan system trauma. A retrospective study of all victims involved in three-wheel motor vehicle accidents admitted to the UCSD Trauma Unit between July 1980 and July 1985 is presented. Injury severity was assessed using the Abbreviated Injury Scale (AIS) and the Injury Severity Score (ISS). The average patient age was 23.3 years with 30% under 16 years of age. There was a male to female ratio of 14:1. The average hospital stay was 12.4 days. Six percent died as a result of their injuries. Injuries to the head and neck were sustained by 83.3% of patients, facial injuries by 46.6%, injuries to the chest by 13.3%, and injuries to the pelvis and abdomen by 13.3%. Thirty percent suffered injuries to the extremities and over 50% had abrasions, contusions, and/or lacerations. Physicians, the public, and state and federal agencies are urged to promote safer use of these recreational vehicles.

Financial risk, hospital cost, complications and comorbidities (CCc) in non-CC stratified urology diagnostic related groups

The federal Medicare Diagnosis Related Group payment mechanism is undergoing constant change. Significant interest has been generated at the health policy level regarding reimbursement for patients with complications and comorbidities. The purpose of this study was to analyze hospital resource consumption for patients in the seventeen urology non-complicating condition (CC) stratified Diagnostic Related Groups (DRGs), currently 45 percent of urology DRGs. We analyzed 185 Medicare patients in these non-CC stratified urology DRGs and found that patients with more CCs per patient had higher total hospital costs per patient, financial risk under DRGs, a greater percentage of outliers, and a higher mortality, than patients in these same DRGs with fewer CCs per patient. These findings suggest that the current DRG system is inequitable to some patients and certain hospitals vis-a-vis non-CC stratified urology DRGs. The Health Care Financing Administration has not significantly changed the complicating condition urology DRG classification, as of its recent May, 1988 legislation. Financial disincentives to treat these patients may affect both their access and quality of care in the future.

Financial risk and hospital cost for elderly patients in non-age stratified surgical DRGS

Hospitals face increasing uncertainty under prospective payment systems such as Medicare's DRG system. We analyzed the equity of the DRG system for 2622 Medicare surgical patients in the 82 non-age stratified surgical DRGs. Patients age 70 and over had higher total hospital costs (P less than .05), a longer hospital length of stay, more diagnoses per patient, losses under DRG payment (P less than .01), a greater percentage of outliers (P less than .05) and higher mortality than patients in these same DRGs under 70 years of age. This data suggests that the current DRG classification scheme may be inequitable vis-a-vis older Medicare patients in the non-age stratified surgical DRGs, and could provide financial disincentives that limit both their access and quality of care in the future.

Effect of total lymphoid irradiation on functional status in chronic multiple sclerosis: importance of lymphopenia early after treatment--the pros

To determine whether immunosuppression by total lymphoid irradiation (TLI) slowed deterioration of chronic progressive multiple sclerosis (MS), functional impairment score and blood lymphocyte counts were compared at 6-month intervals through 4 years following treatment of MS patients by either TLI (n = 27) or sham irradiation (n = 21). At each interval, 20 to 30% fewer TLI-treated patients had deteriorated (p less than 0.05 at 6, 12, and 18 months), and the difference in mean functional impairment score between groups became progressively greater (p less than 0.01 at 42 and 48 months). Benefit accrued principally to the 17 TLI-treated patients with absolute blood lymphocyte counts less than 900/mm3 3 months after treatment, whose mean functional impairment score remained within 0.6 units of baseline (p = NS), whereas the ten TLI patients with higher post-treatment lymphocyte counts had progressive deterioration (p less than 0.05 to p less than 0.001 versus TLI-treated patients with lower lymphocyte counts at all intervals except 30 months) and had deteriorated by more than 5 functional scale units by 42 and 48 months. Side effects were minor and complications rare in TLI-treated patients, but one TLI-treated patient developed staphylococcal sepsis. Thus, TLI slows deterioration of chronic progressive MS, with what appears to be enduring benefit through 4 years compartmented to patients with greater induced lymphopenia. Modification of lymphoid irradiation regimens to increase the proportion of MS patients who achieve a favorable degree of lymphopenia and to avert functional hyposplenism may further improve the benefit/risk ratio.

Visual evoked potentials to multiple temporal frequencies. Use in the differential diagnosis of optic neuropathy

The usefulness of the visual evoked potential (VEP) in differential diagnosis increases when stimulus parameters such as check size and grating orientation are varied. In this study we varied the stimulation frequency. Temporal frequency-specific abnormalities were compared in three patient categories, including retrobulbar optic neuritis (eight patients), pseudotumor cerebri (11 patients), and thyroid eye disease (seven patients). All patients had minimal clinical evidence of optic nerve damage when tested. A 2.3 cycle-per-degree sinusoidal grating of 55% contrast was phase reversed at either 1 or 4 Hz. The P1 latency of the 1-Hz data and the phase at 8 Hz, the second harmonic of the 4-Hz input frequency, were measured. In retrobulbar neuritis, latency (phase) was severely abnormal at both temporal frequencies. In thyroid eye disease, VEP phase was abnormal at 8 Hz while the P1 latency was normal at 1 Hz. The P1 latency and phase were normal in most cases of pseudotumor cerebri. The results suggest differing mechanisms for damage in compressive vs primary demyelinating neuropathies.

The Computer-Assisted Postmortem Identification (CAPMI) System: a computer-based identification program

The Computer-Assisted Postmortem Identification (CAPMI) system was developed at the U.S. Army Institute of Dental Research to facilitate rapid identification of human remains. The increasing requirement for dental based identification of high-energy fatalities and decomposed remains has dovetailed with the development of computer capabilities permitting automation of most of the highly repetitive chart-by-chart screenings characteristic of traditional identification taskings. This report summarizes the concepts upon which CAPMI is based, describes how it works, and reviews suggested applications and limitations. CAPMI software is available to governmental, civic, or humanitarian organizations at no cost.

Financial risk, hospital cost, and complications and comorbidities in medical non-complications and comorbidity-stratified diagnosis-related groups

A number of methods are being studied to modify and improve the accuracy of the Medicare Diagnosis-Related Group (DRG) hospital classification system. This study analyzed resource consumption for 2,431 medical Medicare patients in the 53 non-complicating condition-stratified (i.e., non-complication and comorbidity) medical DRGs. Resource consumption per patient increased as the number of complications and comorbidities per patient per DRG increased, as measured by total hospital cost, hospital length of stay, the number of diagnoses and procedures per patient, the percent outliers, and mortality. Patients with more than four complications and comorbidities generated significant financial risk ($5,667 loss per patient) under DRG reimbursement. This study raises the question of the equity of DRG reimbursement for the medical non-complication and comorbidity-stratified DRGs. A method for DRG adjustment based on complications and comorbidities should be implemented by Congress to assure equitable payment for patients in these medical DRGs.

Age, resource consumption, and outcome for surgical patients at an academic medical center

Many changes are under way in the payment for physician and hospital care of the surgical patient. Relatively little data have been analyzed on resource consumption for hospitalized surgical patients. The purpose of this study was to characterize hospital resource consumption and outcome by age for surgical patients. All surgical admissions at a large academic medical center from Jan. 1, 1985, through March 31, 1986, were analyzed by means of the diagnostic related group (DRG) format. Total costs (exclusive of physician fees) for the 7341 surgical patients studied were $58,206,815. Mean cost per patient, length of stay, percent of outliers, and mortality increased with age. DRG case-mix index and the number of procedures per patient peaked at age 69 and then decreased. Emergency admission was high for the young (i.e., aged 18 to 24 years) and for very elderly patients (i.e., aged over 75 years). Blood transfusions increased steadily as the age of the patient increased; use of surgical intensive care units increased until age 64 years, then plateaued. This study demonstrated a number of trends in surgical patient age and use of resources. Under prospective payment systems (i.e., DRG reimbursement) financial risk increased with the age of the patient. Length of hospital stay and mortality increased with age; however, DRG case-mix index and the number of procedures per patient peaked at age 69, which suggests that elderly surgical patients (i.e., those above 70 years of age) may be more severely ill on average than younger patients.

Environmental-genetic interactions in experimental hypertension: The Dahl rat model

Dahl selected lines of salt-sensitive rats respond to hypertensinogenic stimuli such as sodium or behavioral stressors with marked elevations in blood pressure. In contrast, Dahl salt-resistant rats do not. The two lines appear to differ in terms of heart-rate reactivity and central nervous system organization.

Antibodies to the neuronal cytoskeleton are elicited by Alzheimer paired helical filament fractions

Antibodies were raised to paired helical filament (PHF) enriched fractions obtained from brains of individuals with Alzheimer disease by extraction with ionic detergent followed by sucrose gradient centrifugation. Electron microscopic examination showed that the fractions were enriched in Alzheimer PHF but contained also lipofuscin, amyloid, granular material and membranous elements. Analysis of these fractions with SDS-PAGE stained with Coomassie blue showed only a faint band at approximately 60 kDa while most of the material was excluded from the stacking gel. BALB/c mice were injected weekly with 100 or 200 micrograms of these fractions or corresponding fractions from age-matched control brains. The 3 mice injected with Alzheimer brain, but not the 5 mice injected with control brain fractions, produced antibodies that reacted with central and peripheral nervous system axons, Alzheimer neurofibrillary tangles in intact tissue as well as with isolated, SDS-treated paired helical filaments. In gel strips antibodies from all 3 mice injected with Alzheimer brain fractions reacted with the 200-kDa and 168-kDa but not the 68-kDa neurofilament subunits. The 3 antisera reacted also with some forms of the microtubule-associated protein tau. Adsorptions with the insoluble fraction from Alzheimer but not from control brains blocked staining of axons and NFT by all 3 antisera. Adsorption with highly purified neurofilament proteins or with a preparation containing the 200-kDa and 168-kDa neurofilament subunits blocked axon and NFT immunostaining only in one antiserum. Adsorptions with microtubule protein, heat-stable microtubule-associated protein, or a preparation of tau did not completely block immunostaining by any of the 3 antisera. These results demonstrate that fractions enriched with Alzheimer paired helical filaments contain insoluble neurofilament, tau and other yet unidentified antigens.

Filaments of Pick's bodies contain altered cytoskeletal elements

Pick's disease, a form of progressive senile dementia, is distinguished by the presence of neuronal inclusions known as Pick's bodies. The Pick's body consists mostly of sparse 10-20-nm straight filaments admixed with other cytoplasmic elements. This ultrastructural study was undertaken to establish which components of the Pick's body share epitopes with the normal neuronal cytoskeleton and with Alzheimer's paired helical filaments. Vibratome sections from postmortem brains of patients afflicted with Pick's disease were immunostained by means of polyclonal and monoclonal antibodies to neurofilaments, an antiserum to microtubule proteins not cross-reacting with neurofilaments, and an antiserum to Alzheimer's paired helical filaments. All the antibodies have been shown previously to react with Alzheimer's paired helical filaments. The peroxidase-antiperoxidase or indirect immunogold procedure was used for immunostaining. In addition, we used Bodian's silver stain, which has a high affinity for neurofilaments. At the electron-microscopic level the antibodies and Bodian's silver reacted with the straight filaments and some amorphous elements contained within the Pick's body. The following preadsorptions blocked the immunoreaction: neurofilament antibodies with neurofilaments; microtubule antibodies with microtubule protein or a preparation of the microtubule associate protein, tau; antibodies to paired helical filaments with Alzheimer's brain tissue. Treatment of brain tissue containing Pick's bodies with sodium dodecyl sulfate, a solvent of the normal neuronal cytoskeleton, did not dissolve straight 12-nm filaments. The detergent extracted filaments contained the same isotopes as the Pick's filaments in intact tissue. These results demonstrate that the straight filament components of the Pick's body contain the same neurofilament and microtubule epitopes as the Alzheimer's paired helical filaments and that the filaments share insolubility characteristics similar to those of the paired helical filaments. It is proposed that these two structures are related and are derived at least in part from altered components of the normal neuronal cytoskeleton.

Ubiquitin is detected in neurofibrillary tangles and senile plaque neurites of Alzheimer disease brains

Neurofibrillary tangles (NFT) and neurites associated with senile plaques (SP) in Alzheimer disease-affected brain tissues were specifically immunostained with affinity-purified antibody preparations directed against ubiquitin. In addition, a class of neurites seen in brain regions containing NFT and SP were also specifically stained. Cross-reactivity of the ubiquitin antisera for tau protein, neurofilament proteins, and high molecular weight microtubule-associated proteins (MAPs) were ruled out by (i) the inability of the ubiquitin antisera to stain these proteins in immunoblotting experiments and (ii) the inability of tau, neurofilament, and MAP preparations, when preincubated with the ubiquitin antisera, to inhibit the selective neurofibrillar staining observed. Our results are consistent with the suggestion that ubiquitin is covalently associated with the insoluble neurofibrillary material of NFT and SP. We propose that the ubiquitin-mediated degradative pathway may be ineffective in removing these fibrillar structures in Alzheimer disease brain.

Sudden death following white cell transfusion in a premature infant

A 1,700-g, 31 weeks' gestational age infant developed early onset Group B streptococcal septicemia associated with shock and respiratory distress. The infant was treated with antibiotics, exchange transfusion, and white cell transfusion. The infant improved, and then acutely deteriorated following the third white cell transfusion. Cause of death was presumed to be pulmonary sequestration of white cells or anaphylaxis.

Presence and identification of polyamines in xylem and Phloem exudates of plants

Polyamines were identified by high performance liquid chromatography (benzoylation) and by thin layer chromatography (dansylation) in xylem exudates from stems of sunflowers (Helianthus annuus [L.]), mung bean (Vigna radiata [L.] Wilczek), grapevine (Vitis vinifera [L.] cv Grenache), and orange (Citrus sinensis [L.] Osbeck, cv Valencia), as well as in phloem sap (using elution into EDTA) of sunflower and mung bean plants. Putrescine was the major polyamine detected, ranging in concentrations of 150 to 9200 picomoles per milliliter exudate, whereas only trace amounts of spermine were detected. High amounts of putrescine and spermidine were found in EDTA eluates (possibly phloem sap) as compared with elution into water. Concentrations of putrescine and spermidine in xylem exudates were related to the physiological conditions of the plants prior to exudate collection. More putrescine was found in exudates of older than in younger sunflower plants, and salt stress applied to sunflower plants resulted in a higher concentration of putrescine and spermidine in the exudate. The presence and abundance of putrescine and spermidine in xylem and phloem exudates indicate that polyamines may be translocated in plants. This long-distance translocation further supports the hypothesis that polyamines have a regulatory role in plant growth and response to stress.

North American brugian filariasis: report of nine infections of humans

Nine people living in Rhode Island, New York, Pennsylvania, Florida, or California acquired autochthonous brugian filariasis. Each patient had an enlarged lymph node containing a single worm or, in one patient, a pair of worms. Most worms were in lymphatic vessels within the node, but two worms were in the substance of the node. Ten worms were studied, seven female and three male. Female worms contained paired uteri that occupied most of the body cavity of the worm, and male worms contained a single reproductive tract. No worms were gravid. The diameter of the worms was small, 30 micron to 75 micron. The usual diameter of female worms was 65 micron to 75 micron, and 45 micron to 50 micron for male worms. The morphologic features of these worms, their anatomical location, and their geographic distribution are all characteristic of infection with a North American Brugia species.

Pre- and neonatal exposure of the Dahl rat to NaCl: development and regional distribution of myocardial alpha 1-adrenergic and cholinergic receptor sites

The prenatal and/or postweaning effects of a hypertensinogenic high NaCl-containing diet (8.0% NaCl, w/w) on (1) the regional distribution of alpha 1-adrenoceptors and muscarinic cholinergic receptor sites in the heart and (2) the predisposition/resistance to hypertension (HT) were assessed in the inbred Dahl HT-sensitive (S/JR) and HT-resistant (R/JR) rat. The density of alpha 1-adrenoceptors was reduced in the left ventricle but not consistently affected in the ventricular septum, right ventricle, or atria of S/JR offspring with NaCl-induced HT. Both normotensive and hypertensive S/JR rats also displayed a significantly greater density of cholinergic receptor sites in the atria but few consistent alterations in other regions of the heart, compared to R/JR rats. Maternal diet had no effect on the predisposition/resistance to salt-induced HT and little effect on the regional development of alpha 1-adrenoceptors and cholinergic receptor sites. The results of this study suggest that the reduced density of ventricular alpha 1-adrenoceptors in the S/JR strain is a consequence of HT while the elevated density of cholinergic receptors in the atria may be related to the genetic predisposition/resistance to HT.

Development of a radioimmunoassay for the fibrinogen-derived peptide B beta 1-42

The peptide B beta 1-42 is the initial cleavage product of plasmin-mediated proteolysis of the NH2-terminal region of fibrinogen or fibrin I, while beta 15-42 is the major fragment released by plasmin degradation of fibrin II. Numerous studies have described the measurement of plasma B beta 1-42 levels as an index of plasmin activity. Previous assays were indirect and included quantitation of thrombin-increasable fibrinopeptide B immunoreactivity (TIFPB) or measurement of beta 15-42 with an antiserum (132) which cross-reacted with B beta 1-42. We report on a new antiserum (R142) directed against B beta 1-42 which does not cross-react with beta 15-42 or fibrinopeptide B. Employing this antiserum, a specific assay for B beta 1-42 was developed. This assay was used to measure plasmin-mediated B beta 1-42 release from fibrinogen and its subsequent proteolysis by thrombin. The selectivity constant (Kcat/Km) for thrombin cleavage of the B beta 14-15 bond of B beta 1-42 was 10(5)-fold less than that for proteolysis of the same bond in the intact fibrinogen molecule, thus explaining the stability of this peptide in the presence of thrombin activity in the blood. Similarly, the selectivity constant for plasmin cleavage of the B beta 21-22 bond of B beta 1-42 was 140-fold less than that for proteolysis of the B beta 42-43 bond of fibrinogen, indicating that secondary plasmin attack of the B beta 1-42 molecule is not physiologically important. The specific B beta 1-42 assay provided excellent recovery of peptide added to blood or plasma. Comparison of B beta 1-42 levels with TIFPB values in 37 patient samples yielded good correlation over a wide range of levels (r2 = 0.91). The median plasma B beta 1-42 level in 15 normal individuals was 1.2 pmol/mL. This is similar to the previously reported normal range for TIFPB (1 to 4 pmol/mL) but is higher than the normal level of 0.4 pmol/mL reported with the assay employing antiserum 132. This discrepancy reflects rapid removal of Arg (B beta 42) by plasma carboxypeptidase activity resulting in 50% loss of B beta 1-42 immunoreactivity with antiserum 132 but no loss with R142. To circumvent this problem, we have developed a beta 15-42 antiserum (R154) which, like antiserum 132, cross-reacts with B beta 1-42. However, B beta 1-42/beta 15-42 immunoreactivity with R154 is stable in the presence of carboxypeptidase activity.(ABSTRACT TRUNCATED AT 400 WORDS)

Survey of the age structure of "age-relevant" articles in four general medical journals

The authors analyzed clinical research articles (1980 to 1982) in four general medical journals: New England Journal of Medicine, Annals of Internal Medicine, Journal of the American Medical Association, and British Medical Journal. Of the 1943 articles surveyed, 38.2% were judged to be clinically "relevant" to the elderly. "Relevant" articles were further analyzed to determine whether they contained enough older subjects to enable the reader to draw any inferences about the particular disease or diagnostic or treatment modality studied. Criteria for "age sufficiency" included: mean age of study group (means) greater than or equal to 60 years; if means was less than 60 years, two SD or the range included at least one patient aged 70 years; and greater than or equal to 20% of the study group was older than 60 years. Overall, slightly more than 50% of clinically relevant articles had too few older subjects by the authors' quite liberal age criteria. No statistically significant differences were found among the four journals. Of the age-relevant articles, 25.5% had a mean age of sample studied of greater than or equal to 60 years, 10.9% of greater than or equal to 65 years, 5.6% of greater than or equal to 70 years, and 2.3% of greater than or equal to 75 years. The average age of all subjects studied for three conditions commonly found among the elderly was calculated: coronary artery disease (51.7 years); hypertension (49.8 years); and cancer (52.9 years). The authors concluded that many of the original articles of these four journals did not include (for 1980 to 1982) enough older subjects in their study samples to enable readers to draw any valid inferences about the older population itself.

The effect of pertussis toxin on alpha-2-adrenoceptor-mediated pigment migration in fish melanophores

The aggregation of melanin-granules within fish pigment cells (melanophores) can be elicited either by electrical stimulation of intrinsic nerves or by the addition of adrenergic agonists. The pigment aggregation seems to be mediated by alpha-2-adrenoceptors. In this investigation we have used various agonists and antagonists (noradrenaline, (+)- and (-)-adrenaline, isoprenaline, yohimbine and prazosin) to further characterize the pigment-aggregating receptor of Labrus ossifagus. All the results obtained support the notion of alpha-2-adrenoceptor-mediated pigment aggregation. The pertussis toxin, islet-activating protein (IAP), is known to inhibit the alpha-2-adrenoceptor-mediated signal transduction in mammals. We have used IAP to investigated whether fish melanophore alpha-2-adrenoceptors are also inhibited by this toxin. We found that IAP inactivated the alpha-2-adrenoceptor-mediated pigment aggregation in a dose-dependent manner. The inhibitory IAP-effect had a remarkably short onset-time in the melanophores (maximal effect was obtained within 10 min of incubation). Interestingly, binding of an agonist (noradrenaline) to the receptors prevented IAP from exerting its inhibitory action, whereas binding of an antagonist (yohimbine) gave no protection against the IAP-inactivation. In conclusion, the pigment-aggregating receptors of melanophores of L. ossifagus are very similar to the mammalian alpha-2-adrenoceptors. It is possible to inactivate the melanophore receptor system with IAP and this inactivation has a remarkably short onset-time. Stimulation of the alpha-2-adrenoceptors prevents IAP from inactivating the receptor system.

Polyamines and Root Formation in Mung Bean Hypocotyl Cuttings : II. Incorporation of Precursors into Polyamines

The incorporation of [(14)C]arginine and [(14)C]ornithine into various polyamines was studied in mung bean (Vigna radiata [L.] Wilczek) hypocotyl cuttings with respect to the effect of indole-3-butyric acid on adventitious root formation.Both [(14)C]arginine and [(14)C]ornithine are rapidly incorporated into putrescine, spermidine, and spermine, with similar kinetics, during 5- to 24-hour incubation periods. The incorporation of arginine into putrescine is generally higher than that of ornithine. The biosynthesis of putrescine and spermidine from the precursors, in the hypocotyls, is closely related to the pattern of root formation: a first peak at 0 to 24 hours corresponding to the period of root primordia development, and a second peak of putrescine biosynthesis at 48 to 72 hours corresponding to root growth and elongation. Indole-3-butyric acid considerably enhances putrescine biosynthesis in both phases, resulting in an increase of the putrescine/spermidine ratio.It is concluded that the promotive effect of indole-3-butyric acid on putrescine biosynthesis, from both arginine and ornithine, supports the hypothesis that auxin-induced root formation may require the promotion of polyamine biosynthesis.

A modified cervical collar for the immediate postoperative care of the burned neck

We present a modified version of the cervical collar that can be used immediately postoperatively and accommodates bulky bolster dressings. Its benefits include immediate neck hyperextension and immobilization and parallel monitoring of a skin graft or free flap.

Cellular activation of diaziquone [2,5-diaziridinyl-3,6-bis (carboethoxyamino)-1,4-benzoquinone] to its free radical species

Human leukemic cell lines K562 and HL60, and the murine leukemic cell line L1210, reduce Diaziquone (AZQ) (NCS182986) to its free radical anion. With all cell lines, the free radical was observed immediately in both aerobic and anaerobic cell suspensions. The steady-state concentration of AZQ free radicals was approximately 1% of the total AZQ concentration. L1210 cells treated with azide reduced AZQ, but cells treated with diamide and N-ethylmaleimide did not. NADPH and L-cysteine reduced AZQ. The latter did so under anaerobic conditions; the former did so under both anaerobic and aerobic conditions.

Psychologic differences between high-, normal-, and low-renin hypertensives

Sixty-one male subjects with mild untreated essential hypertension were classified by renin-sodium profiling as high renin (HR--13 Subjects), normal renin (NR--33 Subjects), or low renin (LR--15 Subjects). The HR subjects reported significantly more symptoms of sensitivity, depression, anxiety, hostility, paranoia, and psychotic thought than LR subjects on the Symptom Checklist (SCL-90). The NR subjects also reported more symptomatology than LR subjects. Similar differences between HR and LR subjects were found with the Cattell 16 Personality Factor Questionnaire (16PF).

Student perception of faculty role models

Few studies have been conducted on the effect of faculty role models on dental students. Questionnaires were developed to compare faculty self-perceptions with dental students' perceptions of the role they desired to achieve. Results indicated a minimal relationship between the self-perceptions of faculty and the students' identification of their desired future role in the dental profession. Furthermore, faculty were not perceived by students as being the most influential in molding their feelings about the practice of dentistry.

Large-scale reductions in speeding and accidents in Canada and Israel: a behavioral ecological perspective

We assessed the effects of posted feedback and warning ticket programs on speeding and accidents in two cities. In Experiment 1, speeding feedback signs were effective even when 10 were used in Dartmouth, Nova Scotia, and reductions in speeding were associated with reductions in accidents. The effectiveness of the signs was correlated with the number of intersections and residences within 0.5 km beyond them, and the signs had no effect on untreated streets. In Experiment 2, posted feedback and a warning program reduced speeding and accidents on 14 streets in Haifa, Israel.

Eustachian tube obstruction after provocative nasal antigen challenge

To test if allergic rhinitis is associated with abnormal eustachian tube function (ET), juvenile rhesus monkeys were passively sensitized with serum samples from patients allergic to timothy grass or ragweed pollen. Tympanostomy tubes were inserted for direct measurement of ET function by inflation-deflation and forced-response testing before and after provocative intranasal challenge. Intranasal challenge with pollen (antigen) resulted in rhinorrhea and nasal obstruction. Slight increases in passive ET function values and significantly impaired active ET function were observed after antigen challenge. No changes in nasal airway patency or active ET function resulted from control nonantigen pollen challenges. These data complement our studies in man and support the use of this model to evaluate the relationships among allergic rhinitis, ET function and middle ear disease.

Asthma and bacterial sinusitis in children

Signs, symptoms, and radiographic abnormalities of sinusitis are frequent in children with asthma; it is not known whether sinus inflammation is associated with bacterial infection or other mechanisms. Eight asthmatic patients with exacerbation of asthma despite bronchodilator therapy were studied after maxillary sinusitis was confirmed by radiographs. All had cough, wheezing, nasal stuffiness, rhinorrhea and were afebrile. Four patients had headaches, and two had facial pain. Maxillary sinus aspirates were obtained, and bacterial cultures were positive in five: Branhamella catarrhalis (2), nontypeable Hemophilus influenzae (2), Streptococcus pneumoniae (1). Nose and throat cultures did not correlate with sinus cultures. All patients received bronchodilators, and four of eight patients received steroids. All were treated for 14 to 28 days with antibiotics during which seven of the eight patients improved clinically including all with positive sinus cultures. Asthma-symptoms diary scores were kept by five; all demonstrated improvement. Pulmonary-function tests improved in five of seven patients after the antibiotic and asthma therapy including the four patients with positive cultures. Sinus radiographs cleared in three, improved in three, and were unchanged in two patients after antibiotic therapy.

Alpha 1- and alpha 2-adrenoceptor binding in the Dahl rat model of hypertension

Dahl sensitive rats on a high salt diet (DSH group) developed significant elevations in blood pressure (BP). Sensitive rats maintained on a low salt diet (DSL group) and Dahl resistant rats on a high or low salt diet (DRH and DRL groups, respectively) remained normotensive. The DSH and DRH groups displayed a lower density of alpha 2-adrenoceptors (as measured with [3H]-clonidine) in the cerebral cortex than normotensive DSL and DRL groups. In contrast, the density of alpha 2-adrenoceptors in the medulla was significantly lower in the DSH group than the DSL group, but significantly higher in the DRH group compared to the DRL group. The density of alpha 1-adrenoceptors (as measured with [3H]-WB4101) in the hypothalamus was lower in the DSH group than the DSL group but greater in the DRH group than the DRL group. The results suggest that the sensitive and resistant lines can be distinguished by the density of alpha 1- adrenoceptors in the hypothalamus and medulla, respectively. The interactive effects of dietary NaCl and susceptibility to hypertension on adrenoceptors lend further support to the hypothesis that the genetic predisposition to hypertension is associated with a disruption in central adrenergic activity.

Genetic predisposition to hypertension, elevated blood pressure and pain sensitivity: a functional analysis

Pain sensitivity was examined in Dahl hypertension-sensitive (DS) and Dahl hypertension-resistant (DR) rats. The results indicated that hypertensive DS rats had a reduced sensitivity to painful stimulation compared to normotensive DS rats or compared to DR rats. Furthermore, the lower pain sensitivity of even normotensive DS vis-a-vis normotensive DR rats was not due to genetic factors but due to slight variations in blood pressure between lines. These results provide additional experimental support for the contention that elevations in blood pressure result in decreased pain sensitivity.

Preparation, characterization, and use of an antiserum specific for 2',5'-oligoadenylates

Periodate-oxidized ppp(A2'p)3A was coupled in high yield to an acyl hydrazide derivative of bovine serum albumin and the conjugate was used to immunize rabbits. Several potent and specific antisera were obtained, and one was tested extensively. Fifty per cent of the bound probe ppp(A2'p)3A3'[32P]pCp was displaced by compounds containing the moiety -pA2'pA-at concentrations of 20-60 nM and by compounds containing the moiety -p(A2'p)2A- at 1 nM. The 3',5'-oligoadenylate (A3'p)3A was bound more than 10,000 times less tightly than (A2'p)3A. The antiserum can be used in competition assays in which the amount of an antibody-probe complex is measured after binding to Millipore filters or to polystyrene beads. These assays allow the clear detection of as little as 20 fmol (20 microliters of 1 nM) of 2',5'-oligoadenylates.

Myocardial cholinergic receptor sites and enzyme activity in the Dahl model of essential hypertension

The density of muscarinic receptor sites, choline acetyltransferase (ChAT), and acetylcholinesterase (AChE) activity in the myocardium of the Dahl salt-sensitive (DS) and salt-resistant (DR) rat was investigated. Both normotensive and hypertensive (as a result of 8.0% NaCl added to the diet) DS rats displayed a lower concentration of muscarinic receptors and less ChAT and AChE activity in myocardial tissue than normotensive DR rats. Lower receptor site density and enzyme activity in the myocardial of the DS line may reflect decreased vagal tone. If true, this may produce dificits in the ability to appropriately adjust heart rate (HR) in response to elevations in blood pressure (BP). Therefore, the present results may be viewed as exacerbational factors in the pathogenesis of hypertension in the DS line.

Experience with the one-stage perineal repair of rectal prolapse

Our experience with 27 patients undergoing 33 Altemeier procedures for repair of rectal prolapse is presented. The overall recurrence rate during a 1- to 17-year follow-up period is 35 per cent (per patients) or 50 per cent (per operations). There was no mortality and only minimal morbidity, although we were dealing with an elderly group of patients (average age 61 years) with many associated diseases (2.8 diseases per patient). Of 13 patients with successful anatomic repair, ten described it as a success, one developed an anal stricture, and two patients claimed only partial success, despite a perfect anatomic repair, due to lack of improved continence. Our results with the Altemeier procedure for the repair of rectal prolapse are unsatisfactory. However, as the procedure is well tolerated by elderly and sick patients, it should be reserved for those.

Participation of the central cholinergic system in blood pressure regulation in the Dahl rat model of essential hypertension

Participation of the cholinergic system in the regulation of blood pressure (BP) in the Dahl salt-sensitive (DS) and salt-resistant (DR) rat model of essential hypertension was investigated. It was found that systemic administration of 0.25 or 0.50 mg/kg physostigmine (PSTG) to unanesthetized, normotensive DS and DR rats caused a significant elevation in BP but did not affect heart rate. At both dose levels, the pressor response was markedly greater and significantly longer in DS rats than in DR rats. The response in both DS and DR rats was blocked by pretreatment with atropine sulfate but not with atropine methylnitrate. These results suggest that the pressor effects of PSTG are mediated by central cholinergic mechanisms, and enhanced central cholinergic activity may participate in the pathogenesis of hypertension in the DS rat.

Hypogammaglobulinemia with sarcoidlike granulomas

A 12-year-old girl had sarcoidlike syndrome and hypogammaglobulinemia. Pancytopenia and hepatosplenomegaly were noted at age 4 years. Histopathologic study showed typical sarcoidlike granulomas. Chronic lung disease, along with recurrent infections, developed. Immunologic studies revealed common variable hypogammaglobulinemia, abnormal cellular immune functions, and decreased C4 levels. An immunoregulatory defect is suggested as the pathogenesis of this immunodeficiency syndrome, with multisystem sarcoidlike granulomas, hypersplenism, pulmonary disease, and abnormal cellular and humoral immunity.