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1991

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Full-Text Articles in Life Sciences

Effects Of Conalbumin Bound Iron On The Growth Of Salmonella Paratyphi B And Salmonella Thompson, John Nicholas Mason Dec 1991

Effects Of Conalbumin Bound Iron On The Growth Of Salmonella Paratyphi B And Salmonella Thompson, John Nicholas Mason

Dissertations and Theses

I have investigated the possibility that specific conalbumin (ovotransferrin) iron saturation levels enable less virulent strains of Salmonella to become more virulent. Iron starved cells of two pathogenic Salmonella strains, S. paratyphi B var. java and S. thompson, were cultured in iron limited media at 3 different iron conalbumin saturation levels. Results indicate that strains differ significantly at both low and high iron saturation conalbumin. These differences depict a growth advantage for S. paratyphi B which correlates with reports by the Centers for Disease Control that S. paratyphi B was 3 times more frequent in blood isolates than S. …


The Effects Of Selenate, Molybdate And Chromate On The Triiodothyronine Induced Enzyme Activity And Mrna Level For Both Fatty Acid Synthase And Malic Enzyme, Yuan Zhu Dec 1991

The Effects Of Selenate, Molybdate And Chromate On The Triiodothyronine Induced Enzyme Activity And Mrna Level For Both Fatty Acid Synthase And Malic Enzyme, Yuan Zhu

Masters Theses

In chick embryo hepatocytes in culture, triiodothyronine (T3) stimulates enzyme activity, mRNA level and transcription rate for both fatty acid synthase (FAS) and malic enzyme (ME). Recent evidence has demonstrated the effects of selenate, molybdate and chromate on various physiological processes. Little information, however, is available on the effects of these metal ions on the T3- regulated gene expression for FAS and ME.

In chick embryo hepatocytes incubated in a chemically defined medium, addition of sodium selenate (20 μM) coincident with T3 almost completely inhibited the T3-induced stimulation of FAS and ME activity and accumulation of their respective mRNA's. Neither …


Reliability Of Assessment Of Postural Control In The Sitting Position In The Hemiplegic Subjects By Use Of A Functional Reach Task, Karen Dreher Carter Dec 1991

Reliability Of Assessment Of Postural Control In The Sitting Position In The Hemiplegic Subjects By Use Of A Functional Reach Task, Karen Dreher Carter

Rehabilitation Sciences Theses & Dissertations

No single standardized and reliable method exists for measuring postural control in sitting in the stroke patient population. Postural control in sitting is often a portion of the total physical therapy assessment of the hemiplegic patient. The purpose of this research was to investigate the reliability of a functional reach test as a measure of postural control in sitting in the adult hemiplegic population. The measurement method was performed on 23 adult hemiplegic subjects, ages 62-88 years (mean= 73.6 + 7.9 years). Two physical therapists scored the subjects on the functional reach task. once the functional reach measure was obtained …


Food Handling Practices Among Independent-Living Elderly, Judith Dianne Mcdonough Oct 1991

Food Handling Practices Among Independent-Living Elderly, Judith Dianne Mcdonough

Loma Linda University Electronic Theses, Dissertations & Projects

Food has long been recognized as a vehicle of disease transmission; there are more reported illness associated with the consumption of food than all other environmental factors combined. The handling and storage of food are potentially dangerous and demanding chores for those who may have the sensory losses associated with advancing age, fragile health, and limited resources.

Group-administered questionnaires on the knowledge, attitudes, and practices of food handling were given to 276 seniors, aged 55 to 90, from ten mobile home parks randomly selected from San Bernardino and Riverside counties. As an indicator of possible foodborne illness, the questionnaire asked …


Population Dynamics Of Feral House Mice And Meadow Voles On A Dredge Disposal Site, Georgia E. Kratimenos Oct 1991

Population Dynamics Of Feral House Mice And Meadow Voles On A Dredge Disposal Site, Georgia E. Kratimenos

Biological Sciences Theses & Dissertations

The population dynamics of two species was studied for one year on Craney Island in Portsmouth, Virginia. This dredge disposal site provided good habitat for the house mouse, Mus musculus, whose opportunistic behaviors can withstand the sudden changes in a dynamic environment. Although the site was not optimal habitat, a population of Microtus pennsylvanicus, the meadow vole, was sustained there. Of the seven species of small mammals captured, 65% were house mice and 28% were meadow voles. Meadow voles were more successful at establishing short periods of residency than were house mice; on average, each meadow vole was …


High Performance Liquid Chromatographic Separation Of Different Types Of Collagen, Yongjoo Chung Oct 1991

High Performance Liquid Chromatographic Separation Of Different Types Of Collagen, Yongjoo Chung

Chemistry & Biochemistry Theses & Dissertations

The objective of this research was to develop a method for the separation of different types of collagen using a large pore size (100 nm) reversed-phase C-8 column. Three different types of collagen (type I, III, and V) were sufficiently separated on the column using a mobile phase containing water-acetonitrile-trifluoroacetic acid. Collagens found in each HPLC peak were identified using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) to assay the column effluents.

Trifluoroacetic acid (TFA) was used as an ion pair reagent. This compound improved the chromatographic profile for these proteins on a reversed-phase column. It was observed that with …


The Role Of Gaba In Reproductive Neuroendocrine Systems, Robert Carter Mcree Oct 1991

The Role Of Gaba In Reproductive Neuroendocrine Systems, Robert Carter Mcree

Theses and Dissertations in Biomedical Sciences

Local gamma-amino butyric acid (GABA) neurons in the hypothalamus can modulate the luteinizing hormone releasing hormone (LHRH) pulse generating system.

Two animal models (intact and ovariectomized rats) were used to determine the nature of modulation of LHRH release by GABA. The experiment determined the release of LHRH, serotonin (5-HT), and 5-hydroxyindole acetic acid (5-HIAA) during two hormonal states with each model. In the intact rat the proestrus and estrus states were examined, and in the ovariectomized rat in-vitro release was determined with (OVX2) and without (OVX) estradiol treatment.

In-vivo experiments studied the effect of stimulation of GABA receptors …


Osteoinductivity Of Demineralized Bone: A Quantitative In Vitro Assessment, Yihong Zheng Oct 1991

Osteoinductivity Of Demineralized Bone: A Quantitative In Vitro Assessment, Yihong Zheng

Biological Sciences Theses & Dissertations

Acid demineralized bone (DMB) implanted in extraosseous sites induces bone formation. In vivo studies have shown that DMB stimulates the differentiation of mesenchymal cells into osteogenic cells. In this study an in vitro system was developed to demonstrate the osteoinductivity of DMB quantitatively. This in vitro working system was used to assess the osteoinductivity of variously processed DMB products as a means to evaluate their processing protocols. A human dermal fibroblastic (HDF) cell line was initiated from tissue explants as a working model, along with a human periosteal (HPO) cell line as a control. Ground DMB processed by LifeNet Transplant …


Computer Simulation Techniques To Assess Bias And Precision In The Roving Creel Survey Estimator, David L. Wade Oct 1991

Computer Simulation Techniques To Assess Bias And Precision In The Roving Creel Survey Estimator, David L. Wade

Biological Sciences Theses & Dissertations

Fisheries scientists use roving creel survey methods to estimate total catch and total effort of recreational fisheries. Bias in the roving creel estimators had been known to the scientific community, but it had not been quantified. I developed a roving-creel-survey computer simulation model to investigate the bias and precision of roving creel estimators, and estimated parameters for the model based on field observations from the blue crab (Callinectes sapidus) fishery of the Chesapeake Bay. The computer model was used to identify bias in roving-creel effort and catch estimators and to demonstrate survey methods that will reduce this bias. …


Community Structure Of The Macrobenthos In Back Bay, Virginia, Michael F. Lane Oct 1991

Community Structure Of The Macrobenthos In Back Bay, Virginia, Michael F. Lane

Biological Sciences Theses & Dissertations

A study of the subtidal macrobenthos in Back Bay, Virginia was conducted to examine community structure in relation to sedimentary and water quality characteristics. Samples were collected in August and November of 1987 and February and May of 1988 at ten stations.

Three site groups and three temporal groups were identified by cluster analyses of species abundance. Species composition between site groups was relatively homogeneous and eight species accounted for most of the variation between site groups. A comparison of plots of the biological and physical data in discriminant space suggested that variations in the biological data between site groups …


The Influence Of 17-B-Estradiol And Tamoxifen On Protein Profiles From In Vitro Cultured Preimplantation Mouse Embryos, Darrin D. Demoss Aug 1991

The Influence Of 17-B-Estradiol And Tamoxifen On Protein Profiles From In Vitro Cultured Preimplantation Mouse Embryos, Darrin D. Demoss

Morehead State Theses and Dissertations

A thesis presented to the faculty of the Department of Biological and Environmental Sciences at Morehead 'State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Darrin Lee DeMoss on August 16, 1991.


The Physiology And Molecular Biology Of Iron Nutrition For Cyanobacteria, Nancy Walters Unsworth Aug 1991

The Physiology And Molecular Biology Of Iron Nutrition For Cyanobacteria, Nancy Walters Unsworth

Dissertations and Theses

In addition to nitrogen and phosphorus, iron is an essential nutrient for oceanic primary productivity. Unlike nitrogen and phosphorus however, negligible amounts of iron are supplied to surface waters through recycling or mixing but instead from the limited and sporadic input of aeolian particulate. The low concentration of iron that becomes biologically available from the dust places a serious constraint on the heavily iron-dependent processes of photosynthesis and nitrate reduction which affect primary productivity. As much as 47% of the total oceanic primary productivity can be attributed to cyanobacteria making them critical organisms in the biogeochemical cycles. This thesis addresses …


Carnitine Mediated Alterations Of Ethanol And Fatty Acid Metabolism, Randall L. Mynatt Aug 1991

Carnitine Mediated Alterations Of Ethanol And Fatty Acid Metabolism, Randall L. Mynatt

Doctoral Dissertations

The purpose of this dissertation was to examine the effect of dietary carnitine supplementation on ethanol and fatty acid metabolism. Rats were fed Purina chow as such (non-supplemented, NS) or supplemented with 0.5% L-carnitine supplemented CS). Carnitine supplementation for 7d resulted in decreased oxidation of an oral dose of [1-14C]-ethanol. Expired 14CO2 was significantly reduced at hours 4-12 in the CS group. There were no significant differences in urinary excretion of the 14C-label remaining in tissues after 12h was also not significantly affected by carnitine supplementation. Blood-ethanol concentrations (BEC) were 88.5 and 125.9 mg/dl in …


Use Of Hot-Soft Calendering To Increase Gloss And Smoothness Of Light Weight Coated Paper (Lwc), Andrew L. Tanner Aug 1991

Use Of Hot-Soft Calendering To Increase Gloss And Smoothness Of Light Weight Coated Paper (Lwc), Andrew L. Tanner

Paper Engineering Senior Theses

The purpose of this exercise was to investigate the use of Hot-Soft calendering as a means of pre-treatment for lightweight coated grades. The hot-soft calendering was performed at three temperatures and pressures to give nine test groups. These groups along with one non-treated sample, were coated with the same coating and under the same conditions. Testing was performed on the uncoated base stock, the coated paper, and the coated paper after supercalendering.

The results showed that the hot-soft calendering, prior to coating, was beneficial to gloss only at higher temperatures and pressures. At lower temperatures and pressures, no significant change …


Cocaine And Timing: Drug Effects Under A Mixed Fixed-Interval Extinction Schedule, Vincent O. Hodge Aug 1991

Cocaine And Timing: Drug Effects Under A Mixed Fixed-Interval Extinction Schedule, Vincent O. Hodge

Masters Theses

The effects of cocaine hydrochloride (3.2-56.2 mg/kg) were determined in rats performing under a mixed fixed-interval 60-seconds extinction 120-seconds schedule of food delivery. Responses were recorded in successive 5-second bins. With the exception of the highest dose (56.2 mg/kg), cocaine did not significantly affect rate of responding under the fixed-interval component or extinction component, or the time of peak responding under the extinction component. The highest dose significantly reduced response rates and shifted the time of peak responding leftward to quicker and earlier moments. Results are discussed in terms of possible rate- and time-dependent effects of stimulant drugs.


Characterization Of Two Temperature-Sensitive Mutants Of Escherichia Coli Exhibiting An Altered L22 Ribosomal Protein, Bonnie A. Burnette-Vick Aug 1991

Characterization Of Two Temperature-Sensitive Mutants Of Escherichia Coli Exhibiting An Altered L22 Ribosomal Protein, Bonnie A. Burnette-Vick

Electronic Theses and Dissertations

Analysis of E. coli strains SK1047 and SK1048 have shown them to be temperature-sensitive, protein-synthesis deficient. An alteration in ribosomal protein L22 was detected in both strains using two dimensional gel electrophoresis. Protein L22 was purified from both strains by reversed phase high performance liquid chromatography and from two dimensional electrophoretic gels. Purified ribosomal protein L22 was labeled by reductive methylation and used in 23S RNA binding assays with and without ribosomal protein L4. At the permissive temperature, protein L22 from SK1047 bound less efficiently than the control while protein L22 from SK1048 bound as efficiently as the control. At …


Compliance To Dietary Guidelines In Elementary School Food Service, Martha Anne Henry Aug 1991

Compliance To Dietary Guidelines In Elementary School Food Service, Martha Anne Henry

Masters Theses

The purpose of this study was to determine compliance to the Dietary Guidelines for Americans and to Recommend Dietary Allowances in Tennessee elementary school lunch programs and to determine training practices as they are related to nutrition. Fifty six of the 145 school food service supervisors in Tennessee participated in the study, a response rate 39%.

A four-part questionnaire was developed for all school food service supervisors in the state of Tennessee. The first three parts of the questionnaire consisted of items about types of food products used in cooking, the school food service supervisors' participation in training, and demographic …


Determination Of Iron Bioavailability In The Diets Of Pregnant Adolescents In East Tennessee, Joanne L. Pierson Aug 1991

Determination Of Iron Bioavailability In The Diets Of Pregnant Adolescents In East Tennessee, Joanne L. Pierson

Masters Theses

Determination of dietary iron intake and estimation of iron bioavailability in the diets of pregnant adolescents (ages 13 to 18 years) in East Tennessee (N=100) was performed to assess iron nutriture adequacy. Using a combination of two 24-hour recalls and 2-day diet records, results indicated daily total iron intake (14.8 ± 8.9 mg) was below the recommended Dietary Allowance (RDA) of 30.0 md/d for pregnancy. Mean intakes of protein and ascorbic acid were ≥ 150% of the RDA for these nutrients. Using the Monsen and Balintfy model to estimate overall iron bioavailability, the 8.996 ± 1.2% was less than the …


Population Dynamics And Movements Of Problem Black Bears In Great Smoky Mountains National Park, William Henry Stiver Aug 1991

Population Dynamics And Movements Of Problem Black Bears In Great Smoky Mountains National Park, William Henry Stiver

Masters Theses

From 10 July 1967 to 6 December 1989, 341 black bears (Ursus americanus) in Great Smoky Mountains National Park were captured and relocated 570 times. Capture, release, and recovery locations of relocated bears were plotted on topographic maps using the Universal Transverse Mercator grid system. Objectives of this study were to delineate the sex and age structure of problem black bears and to determine factors contributing to the success of black bear relocations.

Excluding cubs and dependent yearlings, mean ages at initial capture of male and female bears were 3.9 and 4.6 years, respectively. Males comprised 619% of …


Relationship Of Diet And Body Composition To Menstrual Irregularities In Female Runners, Dianne F. Rohaus Aug 1991

Relationship Of Diet And Body Composition To Menstrual Irregularities In Female Runners, Dianne F. Rohaus

Masters Theses

The relationship of nutritional intake and body composition to menstrual irregularities was studied in 40 female runners (24 eumenorrheic and 16 oligo/amenorrheic) between the ages of 18-35 years and running 20 or more miles per week. Subjects were recruited from college cross country teams that attended an NCAA Cross country championship, local track club, and University. Eumenorrhea was defined as having 9-12 periods per year while oligo/amenorrhea was defined as having 8 or less periods per year.

A semi-quantitative food frequency was used to evaluate dietary intake for calories, percent of calories from protein and fat. While skinfold measurements (thigh, …


Small Mammal Demographics In North Dakota Conservation Reserve Program Plantings, Larry A. Lysne Aug 1991

Small Mammal Demographics In North Dakota Conservation Reserve Program Plantings, Larry A. Lysne

Theses and Dissertations

During the summers of 1989 and 1990, capture-recapture methods were used to de~ermine small mammal demographics and population dynamics in Conservation Reserve Program (CRP) plantings in north central North Dakota. Four age classes (1-4 years) of CRP plantings were sampled. Small mammal species diversity was low (H'=0.057-0.374). Eight species of small mammals were captured on CRP tracts, with deer mice (Peromyscus maniculatus) comprising 92% of all small mammals recorded. Largest deer mouse populations (64/ha .and 51/ha) occurred in late August and early September, 1990. Peak densities in 1990 were over twice as high as those of 1989. Home range sizes …


Comparative Ontogeny Of Cranial Ossification In The Spotted Salamander, Ambystoma Maculatum, And The Tailed Frog, Ascaphus Truei, Michael Keith Moore Jul 1991

Comparative Ontogeny Of Cranial Ossification In The Spotted Salamander, Ambystoma Maculatum, And The Tailed Frog, Ascaphus Truei, Michael Keith Moore

LSU Historical Dissertations and Theses

The ontogenetic sequence of ossification of the cranium, including descriptions of the development of individual elements, from initial appearance of bone through adulthood, is described for two species of amphibian: the Spotted Salamander, Ambystoma maculatum, and the Tailed Frog, Ascaphus truei. This study is based on cleared-and-stained developmental series of 269 specimens of Ambystoma and 325 of Ascaphus. Nine stages of cranial development are defined for Ambystoma maculatum. By metamorphosis, all bones of the skull of Ambystoma except the articular have begun to ossify. The ossification sequence of Ambystoma shows little interindividual variation; only 6 specimens do not follow the …


Purification And Characterization Of The Prostate Cancer-Associated Antigen: 7e11-C5, Qi Feng Jul 1991

Purification And Characterization Of The Prostate Cancer-Associated Antigen: 7e11-C5, Qi Feng

Theses and Dissertations in Biomedical Sciences

A murine monoclonal antibody (MAb), 7E11-C5, recognizes a prostate organ-specific antigen. Under reducing conditions, the 7E11-C5 antigen exhibited major 100-Kd and minor 70-Kd bands, suggesting that the antigen comprises two peptide chains. The antigen was detected in pooled normal human seminal plasma, xenograft tissue extract of a prostate adenocarcinoma cell line, LNCaP, and tissue extracts of benign prostatic hyperplasia (BPH) and prostate carcinomas, but was not identified in any of the non-prostate tissue extracts tested. Antibodies of the three major prostate-associated antigens (prostatic acid phosphatase (PAP), prostate specific antigen (PSA) and prostate secretory protein (PSP)) were unable to block the …


Nitrogen Dynamics Of The Acacia Senegal Agroforestry System In The Sudan, Zakaria Abdalla Mohammed Saad Jul 1991

Nitrogen Dynamics Of The Acacia Senegal Agroforestry System In The Sudan, Zakaria Abdalla Mohammed Saad

Biological Sciences Theses & Dissertations

The savanna is characterized by low rainfall, poor soil and vegetation types dominated by the Genus Acacia. Agroforestry systems evolved, the most notable of which is Acacia senegal agroforestry system (ASAS). It yields gum acacia, fuel and fodder and improved soil N, P, and pH and stability against erosion.

This study investigated the climatic, edaphic and biotic interactions of the ASAS that govern the nutrient dynamics, mainly N, and biomass. The effects of limited resources of soil, space and photoperiod on biomass, nodulation and rate of N fixation were investigated. Genetic differences among populations were studied. Progenies of selected …


Age Growth And Reproduction Of Black Drum, Pogonias Cromis, In Virginia, Stephen J. Bobko Jul 1991

Age Growth And Reproduction Of Black Drum, Pogonias Cromis, In Virginia, Stephen J. Bobko

Biological Sciences Theses & Dissertations

The black drum, Pogonias cromis, is of great economic importance to the communities of the lower Eastern Shore of Virginia. Fish are sought both commercially and recreationally during their yearly spring spawning run. Although the number of fish caught each year does not rival other exploited species, it is a directed fishery that partially supports many local fishermen, seafood distributors, marinas, motel owners, and restauranteurs.

Black drum were collected during the fall of 1989 and the spring of 1990 to investigate the population dynamics of fish found in Virginia's Chesapeake Bay and surrounding coastal waters. A total of 235 fish …


Mink Research: Wet Vs. Wet/Pellet Feeding Programs, Troy W. Hobbs Jun 1991

Mink Research: Wet Vs. Wet/Pellet Feeding Programs, Troy W. Hobbs

Undergraduate Honors Capstone Projects

Hobbs Fur Farm, of Franklin, Idaho, has been feeding the Fur-Pro pellet (made by Fur Breeders CO-OP, Midvale, Utah) for the past 8 years. Tim Hobbs, the owner, questioned the efficacy of the pellet feed. His concern was the quality of pelt being produced by mink on the wet/pellet feed program. A comparison of mink raised on the wet/pellet feed program vs. mink raised solely on a wet feed program was performed to determine if any significant differences could be noted.


Effectiveness Of Aluminum Sulfate And Ethylenediamine Tetraacetic Acid As Carbohydrate Protectors During Oxygen Delignification, Joey L. Klinge Jun 1991

Effectiveness Of Aluminum Sulfate And Ethylenediamine Tetraacetic Acid As Carbohydrate Protectors During Oxygen Delignification, Joey L. Klinge

Paper Engineering Senior Theses

Objective

The purpose of this thesis will be to examine three carbohydrate protector's effectiveness during oxygen delignification. Today, about half of the lignin can be removed from a conventional kraft pulp through the application of oxygen delignification as an initial stage in the bleaching process. More extensive delignification results in the degradation of pulp carbohydrates, influencing the final pulp qualities.1 Carbohydrates are attacked by the decomposition of hydroperoxides catalyzed by heavy metal ions, free radicals. Carbohydrate protectors function to deactivate the free radicals, reducing the rate of attack on the carbohydrates.2 This thesis is based on the above …


Steam-Explosion Of Wastepaper As A Pulping Process, Edward G. Schmitt Iii Jun 1991

Steam-Explosion Of Wastepaper As A Pulping Process, Edward G. Schmitt Iii

Paper Engineering Senior Theses

Recycling is a major concern in the nineties, and therefore wastepaper recycling is also in the spotlight. This concern has made it necessary to explore new ways to handle wastepaper. Steam-explosion is a possible pulping process that has the capabilities of handling grades that previously have not been used.

The effects of steam-explosion on 100% laser and Xerox printed paper were studied and the resulting optical properties determined. Chemical addition, residence time, pressure, and dispersant level were varied in the steam-explosion trials. A Morton Slush Maker was used to simulate conventional hydra-pulping for comparison with the steam-explosion pulp.

Steam-explosion removes …


1-Nitronaphthalene Causes Ultrastructural Changes Primarily In Nonciliated Bronchiolar Epithelium Followed By Ciliated Epithelium In The Rat, John-Michael Sauer Jun 1991

1-Nitronaphthalene Causes Ultrastructural Changes Primarily In Nonciliated Bronchiolar Epithelium Followed By Ciliated Epithelium In The Rat, John-Michael Sauer

Masters Theses

This study describes morphological changes in the lung at several time intervals following a single injection of 1-Nitronaphthalene (100 mg/kg intraperitoneal) in male Sprague-Dawley rats using transmission and scanning electron microscopy. Dilation of the smooth endoplasmic reticulum and mitochondrial distension in the nonciliated bronchiolar (Clara) cells was apparent as early as 1 hour after injection, while adjacent ciliated cell showed minimal changes. At 6 hours, when respiratory distress was apparent in the animals, Clara and ciliated cells exhibited chromatin clumping, loss of mitochondrial cristae and cytoplasmic vacuolization. Also at 6 hours, the interstitial area around the terminal bronchioles was infiltrated …


Effect Of Age On The Structure Of Meissner Corpuscles In Forepad Digital Pads Of Mice, Roger C. Mathewson Jun 1991

Effect Of Age On The Structure Of Meissner Corpuscles In Forepad Digital Pads Of Mice, Roger C. Mathewson

Loma Linda University Electronic Theses, Dissertations & Projects

Meissner corpuscles in forepaw digital pads of albino mice were examined by light and electron microscopy to determine structural age-changes. After 1.5 months of age, no intraepidermal nerve fibers were seen extending from corpuscles. From young (1.5-6 months) to middle age (9-15 months), corpuscles became larger and more complex, gaining more horizontally arranged terminals, associated lamellae and connective tissue. At old age (18-26 months), corpuscles became small and lobulated, appearing disorganized. There was no loosening of the corpuscle-epidermal interface. An increase in collagenous connective tissue and basal lamina duplication occurred with advancing age. Ultrastructural age-changes consisted of disorganization of the …