Search PubMedSearch

Biomedical subjects

R C Harvey

Publications and source records attributed to R C Harvey.

At least 19 recordsLinked to original sources

Sporadic meningococcal disease in adults: results of a 5-year population-based study.

OBJECTIVE: To define the incidence, demographics, clinical features, and risk factors for sporadic meningococcal disease in adults (> or = 18 years) residing in metropolitan Atlanta. DESIGN: Prospective, population-based surveillance, with retrospective review of clinical and laboratory records. SETTING: Eight-county metropolitan Atlanta area. PATIENTS: All adult patients in whom Neisseria meningitidis was isolated from normally sterile sites (blood, cerebrospinal fluid) during the period 1 December 1988 to 30 November 1993. MEASUREMENTS: Incidence, relative risk, clinical and laboratory parameters, and serogroup of meningococcal isolates. RESULTS: For the 5-year period, 44 (33%) of 132 cases of meningococcal disease in Atlanta occurred in adults (annual incidence, 0.50/100,000 adults per year). Twenty-three (52%) of the 44 adults presented without rash or meningitis, the two most obvious signs of meningococcal disease. Pneumonia, sinusitis, or purulent tracheobronchitis, but without rash, were the likely sources of meningococcal bacteremia in 15 (34%) of the 44 adults. Twelve of the 15 patients with meningococcal respiratory infection were older than 50 years of age or were immunocompromised (or both), and three fourths of the 15 patients had disease caused by serogroups B, Y, and W-135. Overall, two thirds of adults older than 24 years of age with meningococcal disease had one or more immunocompromising conditions (for example, low complement 50 level [CH50], corticosteroid use, congestive heart failure, multiple myeloma, human immunodeficiency virus infection). Meningococcemia or meningococcal meningitis, often caused by serogroup C, were the presentations in 14 of 15 adults 18 to 24 years old; only 2 had an identified underlying condition. CONCLUSIONS: In this 5-year population-based study, one third of all cases of sporadic meningococcal disease occurred in adults. Over half of the adults presented without rash or meningitis. Pneumonia, sinusitis, and tracheobronchitis are important sources of bacteremic meningococcal disease, especially in immunocompromised patients and elderly persons.

Adolescent

Communicating hydrocephalus in dogs with congenital ciliary dysfunction.

Magnetic resonance imaging (MRI) and radionuclide ventriculography were performed in 5 dogs with congenital ciliary dysfunction (CDD) and 3 normal dogs. Ventricular and brain dimensions and volumes, and CSF flow rates were measured or calculated from the MR images and radionuclide clearance. All CCD dogs had hydrocephalus based on previously published criteria of a percent vertical brain dimension (PVBD) greater than 14%. The PVBD was significantly larger (p = 0.001) in the dogs with CCD (mean +/- SD) 33.00 +/- 5.42% than in normal dogs (11.07 +/- 0.61%. The ventricular volume was significantly larger (p = 0.021) in CCD dogs 10,841 +/- 4,127 mm3 compared to the volume measured in normal dogs 3,069 +/- 1,167 mm3. The CSF flow rate was not significantly different p = 0.876) between CCD dogs (253.00 +/- 147.25 mm3/h) and normal dogs (267.667 +/- 47.61 mm3/h). This suggests that the ventricular dilation in CCD dogs is not due to impedance of CSF flow from the ventricular system by dysfunctional ependymal cilia.

Animals

A population-based assessment of invasive disease due to group B Streptococcus in nonpregnant adults.

BACKGROUND: Group B streptococci (Streptococcus agalactiae) are a major cause of meningitis and septicemia in neonates and pregnant women, but the importance of group B streptococcal disease in nonpregnant adults has not been clearly defined. METHODS: We conducted a prospective surveillance of the pathogens responsible for meningitis for a period of 24 months in 35 hospitals and a referral laboratory in metropolitan Atlanta. We reviewed the clinical and laboratory records of all the nonpregnant adults identified as having invasive group B streptococcal disease during this period. RESULTS: During 1989 and 1990 there were 424 patients with invasive group B streptococcal disease (annual incidence, 9.2 cases per 100,000 population). Of these patients, 46 percent were 1 month of age or younger, 6 percent were older than 1 month but younger than 18 years of age, and 48 percent were 18 or older. Men and nonpregnant women accounted for 68 percent (n = 140) of all cases among adults (annual incidence, 4.4 per 100,000). Clinical and laboratory records were available for 137. In the nonpregnant adult patients (age, 18 to 99 years), the most common clinical diagnoses were skin, soft-tissue, or bone infection (in 36 percent); bacteremia with no identified source (30 percent); urosepsis (14 percent); pneumonia (9 percent); and peritonitis (7 percent). Risk factors included older age (> or = 60 years), the presence of diabetes mellitus, the presence of malignant neoplasms, and infection with the human immunodeficiency virus. The mortality rate in nonpregnant adults was 21 percent, accounting for 67 percent of all deaths related to group B streptococcal infection during the surveillance period. CONCLUSIONS: Invasive group B streptococcal infection is a major problem not only in pregnant women and neonates but also in nonpregnant adults, especially those who are elderly and those who have chronic diseases.

AIDS-Related Opportunistic Infections

Localization of 14 functional J regions in the human T-cell receptor alpha-chain locus.

Nearly 60 unique J alpha regions have been identified in human T-cell receptor (TCR) alpha chains to date, yet fewer than one-third of these have been localized within the alpha-chain locus. We report a rapid method for the mapping of productively rearranged J alpha regions using oligonucleotide probes and overlapping phage clones spanning 80 kb of the TCR-alpha locus. Fourteen J alpha regions were mapped using this technique; the positions of five of these have been verified by genomic cloning.

Base Sequence

Increased risk of meningitis and bacteremia due to Listeria monocytogenes in patients with human immunodeficiency virus infection.

The incidence, demographics, and clinical outcome of infections due to Listeria monocytogenes in individuals infected with the human immunodeficiency virus (HIV) were evaluated by prospective population-based surveillance. During a 2-year study period, 37 cases of invasive listeriosis occurred in metropolitan Atlanta (annual incidence, 0.8 case per 100,000 population). Seven of these cases occurred in known HIV-infected individuals (19% of all cases); five had an AIDS-defining illness, and the other two had CD4 lymphocyte cell counts of < 200/microL. The estimated incidence of listeriosis among HIV-infected patients in metropolitan Atlanta was 52 cases per 100,000 patients per year, and among patients with AIDS it was 115 cases per 100,000 patients per year, rates 65-145 times higher than those among the general population. HIV-associated cases occurred in adults who were 29-62 years of age and in postnatal infants who were 2 and 6 months of age. Mortality among the HIV-infected group was 29%. L. monocytogenes serotypes 1/2a, 1/2b, and 4b were isolated from the HIV-infected patients. L. monocytogenes is an important opportunistic pathogen in HIV-infected patients.

AIDS-Related Opportunistic Infections

Invasive Haemophilus influenzae disease in adults. A prospective, population-based surveillance. CDC Meningitis Surveillance Group.

OBJECTIVE: To define the incidence of and possible risk factors for invasive Haemophilus influenzae disease in adults. DESIGN: Prospective, population-based surveillance of hospital and referral bacteriology laboratories. SETTING: Metropolitan Atlanta, Georgia community. PATIENTS: All patients with H. influenzae isolated from normally sterile sites (blood, cerebrospinal fluid, joint, pleura) from 1 December 1988 through 31 May 1990. MEASUREMENTS: Isolates of H. influenzae were analyzed for serotype and biotype status, outer membrane proteins, lipooligosaccharide phenotypes, ribotyping patterns and beta-lactamase production. RESULTS: A total of 194 cases of invasive H. influenzae occurred (annual incidence of 5.6 cases/100,000 population), of which 47 (24%) were in adults 18 years old or older (annual incidence 1.7 cases/100,000 adults). Adults with invasive H. influenzae ranged from 18 to 96 years; 79% were women. Bacteremic pneumonia accounted for 70% of the adult cases. Other sources for invasive H. influenzae in adults were obstetric infections, epiglottitis, and tracheobronchitis; one patient had meningitis. Underlying conditions were noted in 92% of the patients. Chronic lung disease was the most common risk factor, but pregnancy (annual incidence, 4.9/100,000 pregnant women), HIV infection (annual incidence, 41/100,000 known HIV-infected adults), and malignancy were also important. Overall mortality was 28% in adults, and over half of pregnancy-related infections resulted in fetal death. Fifty percent of the 40 isolates available for testing were serotype b; 47.5%, nontypable; and 2.5%, serotype f. Sixteen of the 45 isolates (36%) were ampicillin-resistant. Based on biotypes, outer membrane protein profiles, lipooligosaccharide phenotypes, and ribotyping patterns, the type b isolates showed less heterogeneity than the nontypable isolates but were distinguishable from one another. CONCLUSIONS: Adult cases currently represent one quarter of all cases of invasive H. influenzae disease. Half of the reported adult cases were caused by type b H. influenzae, and the rate of ampicillin resistance in H. influenzae isolates from adults was higher than previously reported. Haemophilus influenzae is an important cause of bacteremia in compromised adults.

Adolescent

Precautions when using mask induction.

There are few techniques as frequently employed in veterinary anesthesia that are more dependent on good clinical judgment, technical skill, and finesse than mask induction. The technique can be extremely valuable in selected patients.

Anesthesia, Inhalation

An attempt to eradicate Herpesvirus simiae from a rhesus monkey breeding colony.

In the fall of 1987 an attempt to establish a Herpesvirus simiae (B-virus)-negative rhesus monkey (Macaca mulatta) breeding colony was initiated at the Armstrong Laboratory. A serologic testing program was used to identify all monkeys into groups that were either positive or negative to B-virus based on serologic tests. Segregation of the groups allowed the creation of breeding harems that were exclusively seropositive or -negative to B-virus. Animals that were serologically positive were kept in breeding to maintain infant production levels not unlike those previous to segregation. Decreasing numbers of animals converted to a positive status during the first three serum tests for B-virus in the program. During 1990, an increase in the number of monkeys converting to positive status and the discovery of an indeterminate status demonstrated that latency of B-virus in the rhesus may have the potential to defeat an eradication attempt not conscientiously pursued.

Animal Husbandry

Otoacoustic emission in a dog.

A 7-month-old female Poodle was evaluated for a sound continuously emanating from its left ear. The frequency and intensity of the tone was matched by use of a multifrequency audiometer. The frequency and intensity of the sound were 9,594 Hz and 45.5 decibels sound pressure level, respectively. On the bases of normal brain stem auditory-evoked responses and behavioral response to sound, the dog was believed to have normal hearing in both ears. Emission of sound from an ear, referred to as an otoacoustic emission, is a condition that has been reported in human beings and small animals. Successful treatment in human patients with drugs and masking sounds is difficult, and treatment has not been reported in animals. This condition in dogs is not considered life-threatening.

Animals

Characterization of a candidate bcl-1 gene.

The t(11;14)(q13;q32) translocation has been associated with human B-lymphocytic malignancy. Several examples of this translocation have been cloned, documenting that this abnormality joins the immunoglobulin heavy-chain gene to the bcl-1 locus on chromosome 11. However, the identification of the bcl-1 gene, a putative dominant oncogene, has been elusive. In this work, we have isolated genomic clones covering 120 kb of the bcl-1 locus. Probes from the region of an HpaII-tiny-fragment island identified a candidate bcl-1 gene. cDNAs representing the bcl-1 mRNA were cloned from three cell lines, two with the translocation. The deduced amino acid sequence from these clones showed bcl-1 to be a member of the cyclin gene family. In addition, our analysis of expression of bcl-1 in an extensive panel of human cell lines showed it to be widely expressed except in lymphoid or myeloid lineages. This observation may provide a molecular basis for distinct modes of cell cycle control in different mammalian tissues. Activation of the bcl-1 gene may be oncogenic by directly altering progression through the cell cycle.

Amino Acid Sequence

The effect of air abrasive polishing on blood pH and electrolyte concentrations in healthy mongrel dogs.

The recent re-emergence of air abrasive polishing as an adjunct to professional tooth cleaning has been accompanied by a substantial amount of research. Most of this research has focused on the efficacy of the Prophy-Jet and similar devices in the removal of plaque and stain and on the effects of such devices on restorative materials and the various hard structures of the tooth. Little attention has been paid to the effects of mucosal absorption of the sodium bicarbonate in the polishing abrasive. The purpose of this study was to measure any changes in arterial blood chemistry resulting from the use of the Prophy-Jet. The values for pH, sodium, and bicarbonate, as well as other electrolytes, were measured in 10 dogs over a 2 hour period following a 5 minute timed use of the Prophy-Jet. Of all the parameters examined, only the potassium concentration showed a statistically significant change, and the magnitude of this change was not felt to be clinically significant. The pH and concentrations of sodium and bicarbonate remained essentially unchanged with the use of the Prophy-Jet.

Air

Critical care surgical techniques.

A veterinarian dealing with critical and trauma patients must be proficient with techniques for tracheostomy, thoracostomy tube placement for chest drainage, diagnostic peritoneal lavage, and autotransfusion. The utilization of these techniques may be life-saving in the critical patient. A tracheostomy is indicated in any patient with upper airway obstruction that cannot be managed with supplemental oxygen and/or orotracheal intubation. A tracheostomy tube with an inner cannula is preferred. Tracheostomy tubes should be cleaned at 3- to 4-h intervals, and methods should be employed to decrease thick tracheal secretions and to remove them from the trachea. A patient with a tracheostomy tube should be monitored continuously. A thoracostomy tube is indicated in any patient with large and/or continuous accumulation of air, blood, fluid, or chyle in the pleural space. The thoracostomy tube should be at least the same size as the patient's main stem bronchus. The thoracostomy tube is placed aseptically at the seventh intercostal space at the junction of the upper one third and lower two thirds of the lateral chest wall. Fluid or air may be removed from the chest intermittently with a three-way stopcock attached to the thoracostomy tube and a 60-ml syringe. If continuous drainage is needed, a continuous underwater seal and suction system should be used. Diagnostic abdominal paracentesis and peritoneal lavage are useful techniques in the determination of abdominal trauma, hollow viscus rupture, peritonitis, hepatic trauma, and urinary system trauma. When a multiholed catheter and lavage are used, the accuracy of detecting abdominal trauma is 95 per cent. When only needle paracentesis is used, the accuracy drops to 47 per cent. Abdominal lavage fluid can be analyzed for bacteria, whole blood, white blood cells, free bilirubin, creatinine, blood urea nitrogen, amylase, alkaline phosphatase, and alanine aminotransferase. Large volumes of whole blood recovered from abdominal or thoracic paracentesis can be reinfused into the patient if needed, providing it is not contaminated or markedly hemolyzed. The blood should be collected aseptically into blood bottles or bags. If the bleeding is ongoing or the blood only a few hours old, anticoagulants should be used. If the hemorrhage is several hours old, then clotting and defibrination has already occurred and the blood can be collected into "dry" bags or bottles. Before use, abdominal blood should be analyzed for urine, bile or fecal contamination. Blood collected from the thoracic cavity is much less likely to be contaminated. Autotransfused blood is administered through a standard blood administration set.

Animals

Translocations and rearrangements in T-cell acute leukemias with the t(11;14) (p13;q11) chromosomal translocations.

Chromosomal translocations involving the T-cell receptor alpha and delta genes at q11 on chromosome 14 are the most common cytogenetic abnormalities in patients with T-cell tumors. We have demonstrated that the t(11;14)(p13;q11) translocation in two T-ALL patients involves the J delta region suggesting that the translocation proceeds or coincides with delta gene rearrangement. Additional rearrangements on both normal and translocated chromosomes 14 are described including rearrangement of both Tcr-alpha and Tcr-delta genes, and deletions within the J alpha region. The polyclonality of rearrangements on the normal chromosome 14 in one of the patient samples demonstrates that T-cell receptor rearrangement continues after the translocation event. The identification of clonally expanded rearrangements involving both the Tcr-delta and the Tcr-alpha genes in a single patient suggests a cascade model for delta----alpha expression may be a viable pathway for T-cell maturation.

Base Sequence

Anesthetic and supportive management during experimental pulsatile flow perfusion studies in calves.

The purpose of this study was to determine the factors influencing successful experimental cardiopulmonary bypass studies using pulsatile flow perfusion and the medications and methodology necessary to produce successful bypass in calves. In six calves showing no cardiopulmonary pathology prior to bypass procedures, successful anesthesia and surgical intervention was accomplished. Animals were maintained on 5 hours of pulsatile flow bypass perfusion. Successful recovery from the procedures was accomplished. In two calves with pre-existing pulmonary pathology, anesthetic and surgical intervention was accomplished with the utilization of extensive anesthetic management and cardiac supportive medications until the animals could be initiated into 5 hours of pulsatile flow bypass perfusion, in spite of major pulmonary dysfunction. In these two animals, attempts to resuscitate upon termination of pulsatile flow perfusion were unsuccessful due to pre-existing excessive lesions in the lungs. This study shows a contrast between complete success of a pulsatile flow system in normal subjects versus the ultimate failure in experimental animals with pre-existing pulmonary pathology. The inability of experimental calves with a diseased lung to resume spontaneous cardiopulmonary function after the challenges of thoracic intervention indicates the unsuitability of animals with marked pre-existing pulmonary disease status for use in cardiopulmonary bypass studies.

Anesthesia, General