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Biomedical subjects

B Griffin

Publications and source records attributed to B Griffin.

At least 19 recordsLinked to original sources
PubMed1998

Maternal cradling and infant nipple preferences in rhesus monkeys (Macaca mulatta).

This study investigated lateral biases in nipple preferences, maternal cradling, carrying, and retrieval in 41 rhesus macaque (Macaca mulatta) mother-infant dyads living in two captive social groups. Observations were made during the first 6 weeks of infant life using a combination of scan sampling and ad-libitum sampling techniques. Infants exhibited a significant left-nipple preference in the first weeks of life but the bias decreased with infant age. Mothers showed a left-arm bias in carrying their infants but no significant lateral bias in cradling or retrieval. Our results suggest that the left-side cradling bias reported in studies of humans and some other primates reflects a bias in the infant's nipple preference rather than in maternal behavior. The infants' preference for the left nipple is consistent with both Salk's (1960) heartbeat hypothesis and with more recent hypotheses linking this lateral bias with brain asymmetry and hemispheric specialization for mother-infant communication.

Age Factors↗
PubMed1996

Persistent Epstein-Barr virus infection in the common marmoset (Callithrix jacchus).

Epstein-Barr virus (EBV) infection of the common marmoset causes long-term infection, with production of antibodies to virus-induced antigens, without clinical illness. Attempts to show the presence of EBV DNA in saliva of infected animals by PCR were initially unsuccessful, although slot-blot hybridization analysis demonstrated that viral DNA was present. Further investigations showed that most samples of pilocarpine-induced saliva, and 33% of the samples of whole mouth fluids (WMF) tested, were inhibitory to PCR. Similar results were found using human WMF. A method of assessing samples of marmoset WMF for the presence of EBV, by PCR using an EBV BamHI W probe, and removing inhibition with Chelex 100, is described. A total of 202 samples from 21 EBV infected, and seven non-infected animals was tested. Five seropositive animals shed virus on every occasion, and 15 intermittently. Two marmosets, infected as neonates, showed progressively increasing humoral responses to viral antigens, and shed virus on every occasion tested over 3 years. When mated with uninfected animals, the latter seroconverted 4 and 6 weeks later, respectively, and later shed virus into their WMF. The naturally infected animals were paired with naive marmosets, and were able to pass on infection. These results establish that long-term, permissive EBV infection occurs in the common marmoset, and demonstrate again the similarities in the response to EBV between marmoset and man.

Animals↗
PubMed1996

Logical observation identifier names and codes (LOINC) database: a public use set of codes and names for electronic reporting of clinical laboratory test results.

Many laboratories use electronic message standards to transmit results to their clients. If all laboratories used the same "universal" set of test identifiers, electronic transmission of results would be greatly simplified. The Logical Observation Identifier Names and Codes (LOINC) database aims to be such a code system, covering at least 98% of the average laboratory's tests. The LOINC database should be of interest to hospitals, clinical laboratories, doctors' offices, state health departments, governmental healthcare providers, third-party payors, organizations involved in clinical trials, and quality assurance and utilization reviewers. The fifth release of the LOINC database, containing codes, names, and synonyms for approximately 6300 test observations, is now available on the Internet for public use. Here we describe the LOINC database, the methods used to produce it, and how it may be obtained.

Clinical Laboratory Information Systems↗
PubMed1995

Physiological characteristics of the supported singing voice. A preliminary study.

The purpose of this study was to develop a definition of the supported singing voice based on physiological characteristics by comparing the subjects' concepts of a supported voice with objective measurements of their supported and unsupported voice. This preliminary report presents findings based on data from eight classically trained singers. Subjects answered questions about their concepts of the characteristics of the supported singing voice and how it is produced. Samples of the supported and unsupported singing voice produced at low, medium, and high pitches at a comfortable loudness level were collected for acoustic, spectral, airflow, electroglottographic, air volume, and stroboscopic analyses. Significant differences between the supported and unsupported voice were found for sound pressure level (SPL), peak airflow, subglottal pressure (Ps), glottal open time, and frequency of the fourth formant (F4). Mean flow and F2 frequency differences were sex and pitch related. Males adjusted laryngeal configuration to produce supported voice, whereas glottal configuration differences were greater in females. Breathing patterns were variable and not significantly different between supported and unsupported voice. Subjects in this study believe that the supported singing voice is resonant, clear, and easy to manage and is produced by correct breath management. Results of data analysis show that the supported singing voice has different spectral characteristics from and higher SPL, peak airflow, and Ps than the unsupported voice. Singers adjust laryngeal and/or glottal configuration to account for these changes, but no significant differences in breathing activity were found.

Acoustics↗
PubMed1995

Stroboscopic signs associated with benign lesions of the vocal folds.

Stroboscopic signs were systematically rated for a group of 80 patients with benign vocal fold lesions, most of whom had either a nodule or a polyp. Each group revealed a characteristic pattern of ranking of signs and exhibited differences of most predominant signs. The results of the ratings were submitted to a multiple discriminant analysis to determine if post hoc stroboscopic ratings could be used to correctly classify patients into one of four diagnostic groups and into one of two treatment groups. All patients except one were correctly classified into the diagnostic groups, and all were correctly classified into the treatment groups. The important signs for classifying patients into the diagnostic groups were roughness of the edge of the affected vocal fold, phase closure pattern, and phase symmetry. The important signs for classifying patients into the treatment groups were roughness of the edge of the affected vocal fold, glottal closure configuration, and vibration characteristics of the affected (or more affected) vocal fold. The results suggest that objective evaluation of stroboscopic examinations can be valuable in correctly diagnosing patients and in selecting the proper treatment regimen for the patient.

Cysts↗
PubMed1995

Endoscopic microsuture repair of vocal fold defects.

The presence of a nonvibratory segment of vocal folds after microlaryngeal surgery is often a cause of poor voice result. The etiology of a nonvibratory segment is due to full thickness epithelial defect followed by secondary wound closure and scar contracture. To reduce scar contracture and nonvibratory segment of the vocal folds, primary repair with a 6-0 chromic endo-knot suture technique was used to close defects and approximate microflaps of the vocal folds. This was done in 18 patients with epithelial defects after resection of benign vocal fold lesions. The pathologic findings included severe polypoid degeneration (n = 7), fusiform laryngeal polyps (n = 5), sulcus vocalis (n = 2), cyst (n = 2), and keratosis (n = 2). Voice was improved in all patients after surgery. Comparison of vocal fold vibration before and after surgery showed improvements in configuration, amplitude, and mucosal wave. Vocal folds that were sutured all had good vibratory characteristics; none had a nonvibrating segment at the site of suture placement. Voice and healing after microsuture technique were near normal by Day 10 and return of mucosal wave was often complete by Day 14. Endoscopic microsuture closure of microflaps of the vocal folds edge is safe and affords the surgeon an opportunity for primary repair with improved functional result.

Endoscopy↗
PubMed1995

Multiplane transesophageal echocardiographic evaluation of mitral valve disease.

With the additional ability to rotate the image around the axis of the centerline of the sector, multiplane transesophageal echocardiography (TEE) improves over single or biplane TEE in ease of use and diagnostic accuracy. This article reviews the anatomic, physiological, and topographic considerations that affect the use of multiplane TEE in evaluation of patients with mitral valve disease. The optimum mitral valve examination includes a true "short-axis" view, obtained by a transverse (zero-degree angle) transgastric image orientation with the probe tip flexed anteriorly, and several "long-axis" views, obtained from various rotations of the basilar multiplane TEE image planes. This provides a useful and accurate means to determine the mechanism of mitral regurgitation, which is useful in planning and timing, determining the likelihood, and predicting the surgical techniques that will be required for mitral valve repair. The postcardiopulmonary bypass (postpump) TEE examination in a patient with mitral regurgitation is a second important component of the process of repair, to determine the presence and severity of residual mitral regurgitation, and identify any complications of surgery. Of 1,550 mitral repair operations studied with postpump echocardiography at our hospital since 1987, a total of 105 (7%) have had second pump runs. Multiplane TEE is also useful to pinpoint the exact site of periprosthetic regurgitation around a mitral prosthesis, enabling direct surgical closure in some cases. Understanding special technical features of multiplane TEE is an important component for optimum utilization of this powerful diagnostic modality.

Echocardiography, Transesophageal↗
PubMed1994

AIDS debate continues.

Explore the source record for details and available documents.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Percutaneous mitral balloon valvotomy in patients with calcific mitral stenosis: immediate and long-term outcome.

OBJECTIVES: This study analyzed the immediate and long-term outcome of percutaneous balloon mitral valvotomy in patients with and without fluoroscopically visible mitral valve calcification. BACKGROUND: Mitral valve calcification has been shown to be an important factor in determining immediate and long-term outcome of patients undergoing surgical mitral commissurotomy. Patient selection has an important impact on the outcome of percutaneous balloon mitral valvotomy. METHODS: The immediate and long-term results of percutaneous balloon mitral valvotomy were compared in 155 patients with and 173 patients without mitral valve calcification. The patients with calcified valves were assigned to four groups according to severity of calcification. RESULTS: Patients with calcified mitral stenosis more frequently were in New York Heart Association functional class III or IV and more frequently had atrial fibrillation, previous surgical commissurotomy, echocardiographic score > 8, higher pulmonary artery and left atrial pressures, higher pulmonary vascular resistance and mean mitral valve gradient and lower cardiac output and smaller mitral valve area. Mitral valve area after valvotomy was significantly smaller in patients with calcified valves (1.8 +/- 0.06 vs. 2.1 +/- 0.06 cm2) and was > or = 1.5 cm2 in 65% of patients with and 83% of patients without calcified valves (p = 0.004). A successful outcome, defined as mitral valve area > 1.5 cm2 without significant mitral regurgitation and left to right shunting, was achieved in 52% of patients with and 69% of patients without uncalcified valves (p = 0.001). The success rate was 59%, 48%, 35% and 33% in subgroups with 1+, 2+, 3+ and 4+ calcification, respectively. The rates of significant left to right shunting and mitral regurgitation after valvuloplasty were similar in the two groups. Estimated survival rate (80% vs. 99%, respectively, p = 0.0001), survival rate without mitral valve replacement (67% vs. 93%, respectively, p < 0.00005) and event-free survival rate (63% vs. 88%, respectively, p < 0.00005) at 2 years were significantly better in the patients with uncalcified valves. Survival rate curves became progressively worse as the severity of calcification increased. CONCLUSIONS: These findings indicate that immediate and long-term results of mitral valvuloplasty are not as successful in patients with fluoroscopically visible mitral valve calcification as in those without calcification.

Calcinosis↗
PubMed1994

Effect of monosaccharides during severe dry heat treatment of coagulation factor VIII concentrates.

During product development of a factor VIII concentrate (Dutch blood banks) the conversion from unsterilized to autoclaved freeze-drying buffer caused impaired product characteristics after severe dry heat treatment (80 degrees C for 72 h). Analysis of the freeze-drying buffers showed the presence of fructose and glucose in heated buffers, resulting from hydrolysis of sucrose. The detrimental effect of glucose and fructose on solubility, yield of factor VIII and color of the heat-treated product was confirmed by freeze-drying and heating products spiked with increasing levels of these monosaccharides. The effect of the use of freeze-drying buffers autoclaved with and without sucrose was examined in two other factors VIII concentrates, S(8) and Z8 (Protein Fractionation Centre, Edinburgh, UK). If sucrose was present during autoclaving of the buffer, a slightly lower yield over freeze-drying and 80 degrees C heat treatment was observed. Since glucose is present as a substrate in the medium for the host cells during cultivation of viruses, its potential effect on the 80 degrees C heated product (Dutch blood banks) was examined during the validation study of the inactivation of HIV-1 and Sindbis. The cultivation cycles for the virus inocula were simulated and residual glucose levels measured. In the supernatant medium of the host cell culture used for the propagation of Sindbis no residual glucose was found. Glucose however was found in the supernatant medium of the host cell culture for propagation of HIV-1, and therefore small molecular weight substances were removed from the actual HIV-1 inoculum by ultrafiltration.(ABSTRACT TRUNCATED AT 250 WORDS)

Buffers↗
PubMed1993

Predictors of survival following relapse or progression of small cell lung cancer. Southwest Oncology Group Study 8605 report and analysis of recurrent disease data base.

BACKGROUND: Survival after relapse or progression of small cell lung cancer (SCLC) is poor. The Southwest Oncology Group (SWOG) initiated a study of modulation of cyclophosphamide (Cy) resistance in this population. At study closure, the value of testing new regimens in previously treated patients was being debated nationally: Is there an independent impact of treatment over favorable prognostic factors? Thus, the authors analyzed the SWOG recurrent SCLC data base. METHODS: A 12-hour infusion of cytosine arabinoside (ara-C) was used as a potential repair inhibitor of Cy-induced DNA damage in patients with relapsed SCLC. A data base of successive SWOG studies in recurrent SCLC was formed. The independent contribution to survival of prognostic factors, type of prior chemotherapy (CT), time from diagnosis, and type of CT on relapse were then assessed. RESULTS: There were 3 partial responses observed in 67 patients, with substantial myelotoxicity. The median survival was 2.5 months, and 16% lived beyond 6 months. The multivariate analysis of the recurrent SCLC data base found that a normal lactate dehydrogenase (LDH) and second-line treatment with etoposide plus cisplatin (EP), if not initially treated with either alternating or complex multidrug regimens, were the only independent predictors of improved survival. The 2-year survival of this subset was 20%. CONCLUSIONS: The Cy/ara-C program cannot be recommended for patients with recurrent SCLC. However, EP independently contributed to improved survival in patients without complex prior CT and a normal LDH. This finding supports future trials of new approaches in certain subsets of SCLC patients with limited prior treatment.

Adult↗
PubMed1993

Response of plasma low density lipoprotein subfractions to oestrogen replacement therapy following surgical menopause.

OBJECTIVE: Epidemiological studies suggest that postmenopausal oestrogen replacement reduces the incidence of cardiovascular disease. The purpose of this study was to establish the effects of oestrogen replacement therapy on subfractions of plasma low density lipoprotein in bilaterally oophorectomized women. DESIGN: In a placebo controlled, double-blind study, patients were randomized on a two to one basis to receive either oestradiol valerate (2 mg/day) or placebo respectively for a period of 16 weeks. PATIENTS: Seventeen women aged 28-51 years who had all had hysterectomy and bilateral oophorectomy at least 2 months before recruitment were assigned to either the active (n = 12) or placebo (n = 5) group. MEASUREMENTS: Plasma lipids, lipoproteins, apolipoproteins and LDL subfractions were determined immediately before and after the treatment period. LDL subfractions were isolated directly from plasma by density gradient ultracentrifugation within 24 hours. Non-parametric statistical analysis was carried out within each group using Wilcoxon's signed rank test for matched pairs. RESULTS: After 16 weeks of treatment, HDL cholesterol, apo A-I and HDL-2 were increased in the group receiving oestrogen (HDL cholesterol +12%, P < 0.01; apo A-I +14%, P < 0.01; HDL-2 +24% P < 0.01). While there were no significant changes in serum cholesterol, LDL cholesterol or triglycerides, the proportion and concentration of the least dense LDL-I subfraction was decreased significantly (-27%, P < 0.05). The LDL subfraction of intermediate density (LDL-II) was decreased in eight subjects, while small, dense LDL-III was unaffected. Overall, these changes resulted in an apparent shift in the distribution of LDL subfractions towards small, dense LDL-III, although there was no net increase in the latter. CONCLUSION: In view of a similar and characteristic response of LDL subfractions to hypolipidaemic drugs that enhance the clearance of LDL via the LDL receptor, the present findings suggest that oestrogen promotes the preferential removal of LDL-I and II by activating LDL receptors. As this effect is normally associated with a reduction in the circulating level of LDL, it should not be regarded as an unfavourable response to oestrogen replacement therapy.

Adult↗
PubMed1992

Comparative effects of fenoldopam mesylate and nitroprusside on left ventricular performance in severe systemic hypertension.

To compare the effects of fenoldopam (n = 15), a selective dopamine-1 agonist, and nitroprusside (n = 14) on left ventricular (LV) function in severely hypertensive subjects (diastolic blood pressure (BP) greater than 120 mm Hg), both agents were infused to reduce diastolic BP by 40 mm Hg (or less than 110 mm Hg). Indexes of LV systolic and diastolic functions were obtained using gated radionuclide angiography before the initiation of treatment and after targeted BP was achieved. Both fenoldopam and nitroprusside effectively reduced systolic and diastolic BP to target levels. Changes in heart rate, peak filling rate and relative end-diastolic volume were similar with both agents. Baseline ejection fraction increased after infusion of both drugs. The magnitude of the increase in ejection fraction was far greater with fenoldopam than with nitroprusside (+22% vs +8%; p = 0.04), despite a lesser reduction in systolic BP (-12 vs -22%, p = 0.002). Furthermore, the reduction in relative end-systolic volume (-35 vs -20%; p = 0.04), and increase in the ratio of peak systolic pressure to relative end-systolic volume (+43 vs +6%; p = 0.007) were greater after fenoldopam than after nitroprusside. The greater increment in parameters of LV systolic function produced by fenoldopam than by nitroprusside suggests an effect on LV performance that is independent of afterload reduction.

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗
PubMed1992

Late (two-year) follow-up after percutaneous balloon mitral valvotomy.

Percutaneous balloon mitral valvotomy (PBMV) compares well with surgical commissurotomy, showing comparable improvement in symptoms and catheterization-proven valve area early after the procedure. This study reports the New York Heart Association class, mitral valve area calculated by echocardiography, and the results of transseptal cardiac catheterization 2 years after PBMV. The data are compared with the status immediately before and after PBMV. Forty-one patients returned to enter the study (mean follow-up time 24 +/- 3 months). All patients were evaluated clinically by the same investigator who had seen them at the time of PBMV. Transseptal cardiac catheterization and echocardiographic analysis (2-dimensional and Doppler echocardiography) were performed on the same day. At follow-up, 17 patients were class I, 20 were class II, and 4 were class III. Although the mitral valve area calculated by cardiac catheterization increased significantly from immediately before to immediately after PBMV there was a decrease in the calculated mitral valve area at 2-year follow-up. Echocardiographic analysis did not show as large an increase in mitral area, immediately after PBMV, and no significant decrease in mitral valve area at 2 years (before PBMV planimetry 1.1 +/- 0.1 cm2; immediately after 1.8 +/- 0.1 [p less than 0.05]; follow-up 1.6 +/- 0.1 [p = not significant compared with immediately after PBMV]). Doppler halftime measurements were similar. PBMV is effective therapy with good midterm results for selected patients with mitral stenosis.

Adult↗
PubMed1992

The prognostic significance of postoperative residual contrast enhancement on CT scan in pediatric patients with medulloblastoma.

The clinical and therapeutic features of 20 patients with medulloblastoma treated at Children's Hospital and Medical Center, Seattle, from 1980 to 1987, were retrospectively analyzed with regard to prognosis. The overall actuarial 5-year survival rate was 63%, with 57% of patients free from recurrence at 5 years. Residual contrast enhancement on CT scans taken immediately postoperatively was associated with a significantly decreased 5-year recurrence-free survival rate; the 5-year recurrence-free survival rate was 100% for those patients without post-operative residual enhancement compared to 41% for those patients with residual enhancement. A high risk group of patients with residual contrast enhancement persisting one year following diagnosis was identified. No patient in this group survived without disease progression. Other factors, including sex, age at diagnosis, evidence of tumor dissemination, or extent of surgical resection as reported by the neurosurgeon, did not significantly influence prognosis.

Adolescent↗
PubMed1992

Phase II evaluation of high-dose intravenous cisplatin for treatment of adult malignant gliomas recurrent after chloroethylnitrosourea failure.

Twenty-one patients with recurrent malignant glioma who had failed prior chemotherapy with nitrosoureas were treated with high-dose intravenous cisplatin on days 1 and 8 of successive 4 week cycles. Fourteen patients were evaluable for response. Four patients showed partial responses; mean time to tumor progression (MTP) was 8 weeks. Six patients stabilized; MTP was 11 weeks. Four patients showed no response. There were no infectious or hemorrhagic complications, but partial hearing loss occurred in 7 patients and severe vomiting in 8 patients. High-dose intravenous cisplatin demonstrates substantial activity against malignant gliomas recurrent after chloroethylnitrosourea (CENU) failure.

Adult↗