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Biomedical subjects

P L Yu

Publications and source records attributed to P L Yu.

At least 55 records · Page 3Linked to original sources
PubMed1987

Plasma cholesterol variation in the National Heart, Lung and Blood Institute Twin Study.

Plasma cholesterol was measured in the fifth decade of the life of 249 pairs of monozygotic (MZ) and 262 pairs of dizygotic (DZ) World War II veteran twins and 70% of the same cohort 10 years later. There were no significant differences between the mean cholesterol values for MZ and DZ twins, and the within DZ pair mean squares were significantly larger than the within MZ pair mean squares for all of the cholesterol variables measured. However, the DZ twins were found to have greater total variance, positive skewness, and leptokurtosis than the MZ twins for total and high-density lipoprotein cholesterol, and the total/high-density ratio. Comparisons with published data revealed that the variance of DZ twins was similar to that of singletons while the MZ twins have smaller total variance, perhaps owing to a missing component of variation. Hypotheses for the source of the differences in the zygosity distributions are proposed including environmental influences (pre- or post-natal and within- or among-families), genetic differences, and selection at the time of induction into the armed services. Because of the differences in total variance of the two zygosities it is difficult to know which estimates of genetic variance or heritability have the least bias. However, these data provide clues that may lead to further understanding of sources of plasma cholesterol variation that could be important to the future understanding of risk for coronary heart disease.

Cholesterol↗
PubMed1987

Lung mechanics and neuromuscular output during CO2 inhalation after airway anesthesia.

Airway anesthesia with aerosolized lidocaine has been associated with an increase in minute ventilation (VE) during CO2 inhalation. The increase in VE may be due to increased neuromuscular output or decreased mechanical load on breathing. To evaluate this we measured VE, breathing pattern, mouth occlusion pressure, and lung mechanics in 20 normal subjects during room-air breathing and then inhalation of 6% CO2-94% O2, before and after airway anesthesia. Measurements of lung mechanics included whole-lung resistance, dynamic and static compliance, and functional residual capacity. Airway anesthesia had no detectable effect on any measurements during room-air breathing. During CO2 inhalation, airway anesthesia produced increases in VE and mean inspiratory flow rate (VT/TI) and more negative inspiratory pleural pressure but had no detectable effect on lung mechanics or mouth occlusion pressure. Pleural pressure was more negative during the latter 25% of inspiration. We concluded that airway receptors accessible to airway anesthesia play a role in determining neuromuscular output during CO2 inhalation.

Adult↗
PubMed1987

Magnetic resonance imaging in multiple sclerosis: analysis of correlations to peripheral blood and spinal fluid abnormalities.

MRI of the brain, peripheral blood (PB) T cell subsets and B cells, CSF T cell subsets, CSF IgG concentration and incidence of CSF oligoclonal bands (OB), and plasma cells were studied in 32 clinically suspected MS patients. The CSF in MS patients with MRI lesions showed increased IgG concentration and higher incidence of plasma cells and OB compared with those without MRI lesions. In PB, the percentage of kappa light-chain positive B cells was significantly increased in patients with abnormal MRI as compared with controls. The correlation of MRI of the head and immunologic studies in MS will be helpful in better understanding the pathogenesis and dynamics of the disease.

Adult↗
PubMed1986

Magnetic resonance imaging. Clinical correlation in 64 patients with multiple sclerosis.

Sixty-four patients with possible, probable, or definite multiple sclerosis (McAlpine criteria) were clinically evaluated using the expanded disability status scale (EDSS) and Scripps neurologic rating scale (NRS). All were examined with a 0.15T magnetic resonance scanner using T2- and T1-weighted images. Correlations between EDSS and NRS scores and severity of disease detected on magnetic resonance imaging were determined. Significant correlations existed between EDSS and NRS with magnetic resonance ratings. Moderate correlations were observed in the motor, cerebellar, and brainstem subgroups of the clinical scales. Significant low correlations existed in the mood/mentation, vision (optic nerves), and bowel/bladder subgroups. Clinical and neuroimaging limitations may account for the lack of higher correlations. Significant correlations suggest the utility of magnetic resonance imaging in monitoring disease progression, and it may prove to be the technique of choice in following up patients with multiple sclerosis.

Adolescent↗
PubMed1986

The VATER association. Analysis of 46 patients.

Evaluation of 46 patients with the VATER association indicates that in addition to the major defects seen in this association, numerous other abnormalities occur at lesser frequency. Four of the defects that are not usually associated with the VATER association, namely, inguinal hernias, small intestinal malformations, choanal atresia, and cleft lip and/or palate, were seen at a relatively high frequency in this patient population. Two children possessed defects found in both the VATER and CHARGE associations. The spectrum of defects in the 46 patients in this study also is compared with that in 186 cases derived from the literature.

Abnormalities, Multiple↗
PubMed1986

Analysis of growth in the VATER association.

Analysis of growth in 31 patients with the VATER association showed that 14 (45%) of these patients experienced postnatal growth deficiency (greater than -2 SDs) for at least the first three years of life or beyond. The other 17 patients (55%) had growth that fell within the normal range but which was usually less than the 50th percentile during at least the first three years of life. Severe cardiac defect was present in nine (64%) of the growth-deficient patients and was the only defect that was significantly correlated with growth deficiency. No explanation for the deficiency in growth in the other five children was found. When growth deficiency was present, it was of postnatal onset.

Abnormalities, Multiple↗
PubMed1986

Human parotid proline-rich proteins: correlation of genetic polymorphisms to dental caries.

Parotid saliva contains a variety of proline-rich proteins. This study found that, among 306 children between the ages of 5 to 15 years, there is a significant increase in the decayed-missing-filled tooth surface (DMFS) score of the permanent teeth with age in children with the specific proline-rich protein phenotypes Pa and Pr. However, the increase in DMFS score of the permanent teeth of children was significantly greater in children with Pa+ and Pr22 than in those with the other phenotypes (Pa- or Pr11 and Pr12). The previously established close correlation between the Pa and Pr phenotypes and the genetic variants of salivary peroxidase (a powerful antibacterial system in the oral cavity) may provide an explanation for the relationship of certain proline-rich protein phenotypes to dental caries.

Adolescent↗
PubMed1986

Volume of blood submitted for culture from neonates.

We prospectively examined 298 sets (298 aerobic, 299 anaerobic, and 73 resin cultures) of blood cultures from 161 critically ill newborns. The attending physicians were unaware of the study. The mean blood volume per patient (aerobic and anaerobic) was 1.05 (range, 0.11 to 3.04) ml. The mean blood volume per aerobic bottle was 0.53 (range, 0.01 to 1.90) ml. Among aerobic samples 2.7% were less than or equal to 0.1 ml, 16% were less than or equal to 0.3 ml, 33% were less than or equal to 0.4 ml, and 55% were less than or equal to 0.5 ml. For anaerobic cultures the mean blood volume was 0.52 (range, 0.01 to 1.79) ml. Among anaerobic samples 2.7% were less than or equal to 0.1 ml, 15% were less than or equal to 0.3 ml, 35% were less than or equal to 0.4 ml, and 58% were less than or equal to 0.5 ml. Blood volume did not correlate with gestational age, chronologic age, or weight. The mean volume of blood submitted in positive cultures was not significantly greater than that in negative cultures. The blood volume used for culture from ill newborns may be inadequate for detecting sepsis, and the adequacy of currently available culture methods needs to be assessed for the small samples submitted from critically ill newborns.

Aerobiosis↗
PubMed1986

Ventilatory response during CO2 inhalation after airway anesthesia with lidocaine.

Airway anesthesia with inhaled aerosolized lidocaine has been associated with increases in minute ventilation (VE) and mean inspiratory flow rate (VT/TI) during CO2 inhalation. However, it is unclear whether these increases are local effects of the anesthesia or systemic effects of absorbed and circulating lidocaine. To evaluate this 20 normal subjects were treated on separate days with aerosolized lidocaine, intravenous lidocaine, aerosolized control solution, or intravenous control solution, and the effects of each treatment on VE and VT/TI were determined and compared during room-air breathing and inhalation of 5% CO2-95% O2. None of the treatments altered VE or VT/TI during room-air breathing. Aerosolized lidocaine produced small (5.9-6.0%) increases in VE and VT/TI during CO2 inhalation, but these effects were not present after intravenous lidocaine despite equivalent lidocaine blood levels. We concluded that the increases in VE and VT/TI after aerosolized lidocaine were local effects of airway anesthesia rather than systemic effects of absorbed and circulating lidocaine.

Adult↗
PubMed1986

Analysis of translocations observed in three different populations. I. Reciprocal translocations.

A sample of 437 reciprocal translocations was classified into three groups according to their method of ascertainment (Group I = couples with repeated abortions; Group II = karyotypically unbalanced carriers; Group III = balanced translocation heterozygotes). Statistical analysis showed that the distributions of chromosome breaks observed in the three groups could not be accounted for by chromosome arm length alone. In couples with repeated abortions, an excess of breaks in 7p, 17p, and 22q was found, whereas in the balanced translocation heterozygotes an excess of breaks was found only in 11q. An excess of breaks was found in arms 9p, 14p, 18p, 18q, 21q, and 22q in karyotypically unbalanced probands. A significant decrease of breaks in the medial chromosome regions was accompanied by a concomitant increase in the terminal regions in all groups. The three groups demonstrated different distributions of chromosome arm involvement in the observed translocations. Balanced translocation heterozygotes had the highest frequency of large (greater than the length of 4p) translocated segments and an excess in the frequency of large-large translocations, whereas karyotypically unbalanced probands had the highest frequency of small (shorter than 21q) translocations and an excess in the frequency of small-small translocations. For each type of chromosomal imbalance observed, the balanced translocation heterozygotes demonstrated the greatest potential imbalance and the karyotypically unbalanced probands the least.

Abortion, Spontaneous↗
PubMed1986

Analysis of translocations observed in three different populations. II. Robertsonian translocations.

A sample of 229 Robertsonian translocations was classified into three groups according to the method of their ascertainment (Group I = couples with repeated abortions; Group II = karyotypically unbalanced probands; Group III = balanced translocation heterozygotes). Statistical analysis showed that the distributions of Robertsonian translocations differed significantly from random in all three groups. Additionally, the distributions were significantly different between couples with repeated abortions and karyotypically unbalanced probands and between unbalanced probands and balanced translocation heterozygotes.

Abortion, Spontaneous↗
PubMed1985

Short- and long-term effectiveness of enteral and parenteral nutrition in reversing or preventing protein-energy malnutrition in advanced neuroblastoma. A prospective randomized study.

The effectiveness of enteral and parenteral nutrition regimens in preventing or reversing protein-energy malnutrition (PEM) and in preventing treatment delays was evaluated in 32 children receiving treatment for newly diagnosed Stage III (3 patients) and IV (29 patients) neuroblastoma. Ten of 18 malnourished patients were randomized to central parenteral nutrition (CPN) and 8 to peripheral parenteral nutrition (PPN) plus enteral nutrition for 4 weeks and then received enteral nutrition (EN: intense nutrition counselling, oral foods and supplements) for weeks 5 through 10. Ten of 14 nourished patients received EN and 4 CPN for 4 weeks and EN thereafter. Dietary, anthropometric and biochemical measurements were determined for weeks 0, 1, 2, 3, 4, 7, and 10 for 24 patients who completed the protocols. In malnourished patients, both CPN (seven patients) and PPN (seven patients) were effective in reversing PEM in the first 4 weeks; thereafter, EN effectively maintained nutritional gains in both groups. In nourished patients, EN (seven patients) was not as effective as CPN (three patients) in preventing PEM during the first 4 weeks; afterwards, EN maintained gains in the CPN group but did not promote needed increases in weight nor fat reserves in the EN group. Patients supported by parenteral nutrition (PN, weeks 1-4) had fewer treatment delays (2/17, 12%) than EN patients (4/7, 57%, P less than 0.05). These data indicate that PN reverses or prevents PEM and prevents treatment delays during the first 4 weeks of intense oncologic treatment and provides nutritional benefits which can be maintained with EN thereafter.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1985

Anthropometric discrimination among affected, at-risk, and not-at-risk individuals in families with Huntington disease.

An earlier report showed significant differences among Huntington disease (HD) patients, controls, and particular age cohorts of at-risk persons for several dimensions of body mass and for several linear and craniofacial components of the body. In this investigation a function was derived from a stepwise discriminant analysis of the affected and unaffected groups, and used to classify the at-risk individuals according to HD gene carrier status. The function, comprised of body mass index, subscapular skinfold, head length, and sitting height, classified 95% of the controls and 87% of the affected individuals correctly. Approximately 80% of the individuals at-risk were classified with 80% or greater certainty. We propose that anthropometric variables may prove to be a powerful tool for basic research in HD and the derived discriminant function has potential clinical value as a diagnostic and preclinical diagnostic aid. We emphasize that corroborative testing on other sample populations of HD families is required before these techniques are utilized. Also, it is imperative that the anthropometric protocol include appropriate standardization of the raw measurement data.

Adult↗
PubMed1985

Description of a genetic polymorphism of a human proline-rich salivary protein, Pc, and its relationship to other proteins in the salivary protein complex (SPC).

A new polymorphism, Pc, has been identified in human saliva. Two proteins, Pc 1 and Pc 2, are determined by alleles Pc1 and Pc2, respectively, which show autosomal codominant inheritance. No null phenotype has been encountered in 225 randomly collected salivas. The frequencies of the two alleles differ in the Black and White American populations, with Pc1 and Pc2 being 0.670 and 0.330 in the Black (N = 47) and 0.461 and 0.539 in the White (N = 178) populations, respectively. The alleles are in equilibrium in the two populations and segregation analyses (30 families) do not suggest the existence of a null allele in either population. Of seven polymorphic human salivary proteins determined by genes in the salivary protein complex (SPC), Pc phenotypes show association only with Ps phenotypes. Based on that association, our linkage studies, and the biochemical similarities with other SPC proteins, we tentatively conclude that Pc is a member of the SPC, bringing the total number of genes in that group to 13.

Alleles↗
PubMed1985

Genetic variability of alkaline phosphatase expression in inbred mouse tissues.

Quantitative alkaline phosphatase (ALP; EC 3.1.3.1) expression varies among various tissues and among inbred mouse strains. There is about a 20-fold difference in ALP activity in lungs from CBA/J and C57L/J inbred strains and this difference is inherited additively with a heritability of 0.84. Studies of thermostability at 56 and 65 degrees C and sensitivity toward inhibitors (L-phenylalanine, L-homoarginine, L-phenylalanylglycylglycine, and levamisole) do not demonstrate differences in the ALP from lungs or liver of the CBA/J and C57L/J strains. The ALP activity in intestine expressed by the intestinal locus varies over 100-fold between A/J and DBA/1J strains. Further studies of the mechanisms resulting in this difference in ALP activity should help elucidate the mechanisms for aberrant expression of ALP in malignancy and for manipulation of low ALP activity in hypophosphatasia.

Alkaline Phosphatase↗
PubMed1985

Ventilatory response to high-frequency airway oscillation in humans.

To investigate respiratory control during high-frequency oscillation (HFO), ventilation was monitored in conscious humans by respiratory inductive plethysmography during application at the mouth of high-frequency pressure oscillations. Studies were conducted before and after airway and pharyngeal anesthesia. During HFO, breathing became slow and deep with an increase in tidal volume (VT) of 37% (P less than 0.01) and inspiratory duration (TI) of 34% (P less than 0.01). Timing ratio (TI/TT) increased 14% (P less than 0.05) and respiratory frequency (f) decreased 12% (P less than 0.01). Mean inspiratory flow (VT/TI) did not change during HFO. Following airway anesthesia, VT increased only 26% during HFO (P less than 0.01), whereas significant changes in TI, TI/TT, and f were not observed. Pharyngeal anesthesia failed to diminish the effect of HFO on TI, TT, or f, although the increase in VT was reduced. These results indicate that 1) HFO presented in this manner alters inspiratory timing without affecting the level of inspiratory activity, and 2) receptors in the larynx and/or lower airways may in part mediate the response.

Adult↗