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Biomedical subjects

C S Wink

Publications and source records attributed to C S Wink.

At least 19 recordsLinked to original sources
PubMed1999

Effects of caffeine on the bones of aged, ovariectomized rats.

Caffeine is a substance which many people consume in their daily life. Caffeine's effects on bone are still controversial. Using ovariectomized rats, the present study was conducted to determine to what extent caffeine intake affects the mechanical properties, bone minerals and histology. Aged rats were divided into 2 groups after ovariectomy. Group 1 was fed a 20% protein diet as a control, and group 2 was fed a 20% protein diet supplemented with caffeine (2 mg/100 g body weight). The respective diets were fed to the rats of each group for 90 days. Rats were then killed by heart puncture, blood was collected, and femurs were removed. In 1 group of femurs paraffin cross-sections were made at the midshaft of each bone. Total width, cortical width, total cross-sectional bone area of the midshaft, and the number of osteocytes in randomly selected areas were measured. Another group of bones was subjected to three-point bending testing until failure. Bones were then pulverized and Ca, P, Mg, Zn, Sr, Si, hydroxyproline and hexosamine contents and crystallite size were measured. Various mechanical properties, except modulus of elasticity, in the caffeine group were consistently 7-23% lower than the noncaffeine controls. Yield strain in the caffeine group was significantly less than in the noncaffeine controls. Zinc, Sr, and crystallite size of bone showed a significant decrease in the caffeine group, whereas Si contents significantly increased. Our current results indicate that routine intake of caffeine in the elderly should be regarded with some caution.

Aging↗
PubMed1999

Effects of caffeine on heart mitochondria in newborn rats.

Caffeine consumption has been implicated in the development of cardiovascular disease. Therefore, in the present study, litters of rats were combined upon birth, and 8 pups were randomly assigned to each dam. Dams with pups were divided into 2 groups: group 1 received a 20% protein diet as a control, and group 2 received the 20% protein diet supplemented with caffeine (4 mg/100 g body weight). Pups from both groups were killed on days 11 and 15. Transmission electron microscopy revealed swollen, disrupted, degenerating mitochondria and intracellular edema in the hearts of rats in the caffeine groups when compared with those of the controls. Plasma Cu concentration was significantly decreased. These results indicate that early exposure to caffeine through maternal milk adversely affects cardiac mitochondria of rat pups and may be associated with decreased plasma Cu levels. It is unclear whether these results apply to the human infant. Interspecies extrapolation from rat to human must be made with caution.

Animals↗
PubMed1999

Periarticular neural elements in the shoulder joint.

Due to its unconstrained nature, the glenohumeral joint must necessarily have several mechanisms to regulate its position in space. The neural mechanisms associated with this positioning have not been fully evaluated anatomically. In this study, three fresh-frozen human cadaveric adult shoulders were dissected. Specimens were excised from the proximal biceps insertion, the superior, middle, and inferior glenohumeral ligaments, and the capsule superior to the glenohumeral ligaments. In two specimens, a portion of glenoid labrum was analyzed using a modified gold chloride staining method and light microscopy. A portion of mid-biceps tendon was used as a control. In the superior glenohumeral ligament, 45% of sections contained neural elements consisting of Golgi's, Ruffini's, and Pacini's corpuscles as well as free nerve endings. The predominant types were Ruffini's and Golgi's. The middle glenohumeral ligament sections revealed all four receptor types in 42%, with the most common elements being Pacini's and Ruffini's receptors. The inferior glenohumeral ligament specimens contained the four receptor types in 48% of sections, with Ruffini's, Pacini's, and Golgi's types equally distributed. The shoulder capsule specimens revealed Ruffini's and Pacini's receptors in 47.5% of sections. Only free nerve endings were identified in the biceps tendon and glenoid labral tissue. These findings suggest that the pattern of neural elements does not appear to be random in nature and may have some correlation with the specific functions of some of the glenohumeral ligaments.

Adult↗
PubMed1996

Effects of caffeine on bone cells and bone development in fast-growing rats.

BACKGROUND AND METHODS: Caffeine exerts harmful effects on fetal and suckling rats. To elucidate the effects of caffeine on bone in growing rats further, dams were fed normal laboratory chow until delivery. At birth, the litters were combined and eight pups were randomly assigned to each dam. Dams with the combined litters were divided into two groups. Dams of group 1 received a 20% protein diet as a control, and dams of group 2 received the 20% protein diet supplemented with caffeine (4 mg/100 g b.w.). Pups from both groups were killed on days 11, 15, 22, and 50. Parameters studied were ultrastructure of femoral osteoblasts, osteocytes, and osteoclasts; the number of osteocytes per area of bone in femoral histological cross sections; structural remodeling and shape of the lateral tibial metaphysis as revealed by scanning electron microscopy; and plasma Cu and Zn concentrations. RESULTS: Rats in the caffeine groups had significantly fewer osteocytes per area of femoral cross section, retarded structural remodeling of the lateral tibial metaphysis, osteoblasts and osteocytes with disrupted swollen mitochondria, and decreased plasma Cu and Zn levels when compared with controls. CONCLUSIONS: These results indicate that if young, rapidly growing rats are exposed to caffeine, disruption of osteoblasts and retarded bone development occur, which could be related to the decreased plasma Cu level in the young animals.

Animals↗
PubMed1994

Alteration of femoral structure in later life by chronically feeding caffeine during rapid growing period in newborn female rats.

The effects of caffeine intake in early life on bone structure later in life were studied in rats. At day 9 of gestation, dams were divided into 2 groups. Group 1 (control) received a 20% protein diet; group 2 received the 20% protein diet supplemented with caffeine (2 mg/100 g body weight). After birth pups were continuously fed their respective diets until day 93, when the diet of group 2 was replaced with a noncaffeine 20% protein diet. On day 388 animals from both groups were weighed, killed, and femora and mandibles were removed. Calcium, phosphorus, magnesium, zinc, hydroxyproline, and hexosamine concentrations were measured. Radiographs of some femora were taken and paraffin cross sections were made at the midshaft of others. Femora in the caffeine group were wider, periosteal bone area/total bone area was greater, the cross sectional area of femoral bone was smaller, and there were fewer osteocytes/bone area than in controls. Calcium, phosphorus, zinc, and hydroxyproline concentrations in the caffeine group were less in both bones of the caffeine group. These results indicate that if animals are exposed to caffeine during the rapidly growing period, changes occur in femoral bone which are similar to those that occur with aging.

Animals↗
PubMed1992

Neural elements in the human temporomandibular articular disc.

The purpose of this study was to determine the presence and describe the location of neural elements in the articular disc of the human temporomandibular joint. Six articular discs were obtained from three adult human subjects at autopsy. Four discs were cut into segments of known anterior-posterior orientation. The remaining two were processed intact. All tissues were stained in bulk with gold chloride, and frozen, sectioned on a sliding microtome at 70 to 100 microns, mounted on slides, dehydrated, and coverslipped. Nerve fibers were seen penetrating the discs from the pericapsular connective tissue. Structures resembling Ruffini endings, Pacinian corpuscles, and Golgi tendon organs were identified in the pericapsular connective tissue and within the disc. The population density of neural elements was the greatest at the periphery of the disc and progressively decreased towards the center, which was essentially devoid of them. The concentration of neural elements appeared to be greater at the anterior and posterior margins of the disc, with the greatest concentration being posteriorly. These findings support the theory that afferent nerves may arise from neural elements within the disc.

Adult↗
PubMed1992

Neural elements in human cervical intervertebral discs.

This study attempted to characterize neural elements within the human cervical intervertebral disc. Cervical intervertebral discs were obtained from four adult human subjects at autopsy. Discs were stained in bulk with gold chloride, sectioned, and viewed with the light microscope. Nerve fibers appeared to enter the disc in the posterolateral direction and course both parallel and perpendicular to the bundles of the anulus fibrosus. Nerves were seen throughout the anulus but were most numerous in the middle third of the disc. Receptors resembling Pacinian corpuscles and Golgi tendon organs were seen in the posterolateral region of the upper third of the disc. These results provide further evidence that human cervical intervertebral discs are supplied with both nerve fibers and mechanoreceptors.

Adult↗
PubMed1991

Tibial dimensions before and during the recovery phase in the osteopetrotic mutant mouse.

Osteopetrosis is a genetic bone disease characterized by excessive bone mass and 'clubbing' of long bones. In the osteopetrotic (op) mouse, remission of the disease begins at 45 days of age. This study attempted to describe changes in the op tibia before and during remission. Osteopetrotic and normal littermates were killed at intervals from 10 to 120 days of age. Left tibiae were processed for transmission electron microscopy. Microradiographs of right tibiae were projected and drawn. Bone dimensions were compared between mutants and controls by ANOVA and bones were viewed in a scanning electron microscope. Differences between mutants and controls were: at all ages mutant tibiae were shorter than those of controls; 10-day distal shafts of mutant tibiae were significantly narrower; 30-day proximal shafts of mutant tibiae were wider, distal shafts were narrower, and there was no bone resorption along the external proximal metaphysis. At 48 days, resorption was seen along the proximal metaphyses of the mutant tibiae and by 60 days, extensive resorption areas were evident. However, proximal shafts of mutant tibiae were still significantly wider than those of controls. These results indicated that before remission there was an unequal deposition of bone on the mutant tibia. After remission, resorption occurred along the external proximal shaft, but was not enough to remove significant amounts of bone from the proximal metaphyses of mutant tibiae by 120 days of age.

Analysis of Variance↗
PubMed1988

Femoral expansion in the adult male rat.

The length, total and cortical widths at midshaft, and robusticity of femora were measured in growing and mature male Holtzman rats. Analysis of covariance revealed significant differences in the regression coefficients (slopes) between young rats (1-4 months) and adult rats (5-16 months), indicating that, for a given increment in femoral length, young rats have a smaller increment in total femoral width than do adult rats. In addition, the results indicated that femoral expansion occurs in adult male Holtzman rats (5-16 months of age) without cortical thinning or loss of bone mass.

Age Factors↗
PubMed1988

Effects of promethazine HCl on osteoporotic femora of adult castrated male rats.

Promethazine HCl (Phenergan) was added to the drinking water (2.4-9.6 mg/kg/day) of castrated adult male Holtzman rats. One group of castrates and a group of normal rats received no drug and served as controls. Treatment was started at castration and continued for 4 months. After controlling for body weight, analyses of covariance and Student-Newman-Keuls tests revealed that promethazine did not prevent the development of femoral osteoporosis in the castrate rats. However, control rats (normal and untreated castrates) had significantly wider femora and thicker cortices at midshaft than did promethazine-treated animals. The results indicated that promethazine HCl had no effect on the development of femoral osteoporosis and retarded normal femoral expansion in the adult castrate male rats.

Animals↗
PubMed1988

Dichloromethylene biphosphonate retards femoral expansion in normal and castrated adult male rats.

This study reports the effects of dichloromethylene biphosphonate (Cl2MBP), an inhibitor of bone remodeling, on femoral expansion in four groups of adult male rats; (1) sham-operated controls; (2) sham operated + injections of Cl2MBP; (3) castrated (osteoporotic), and (4) castrated + injections of Cl2MBP. After controlling for body weight, analyses of covariance revealed significant differences in total femoral width between animals that had received Cl2MBP and those that had not. The results indicated that Cl2MBP treatment retarded femoral expansion in both castrated and normal adult male rats.

Animals↗
PubMed1986

The effects of estradiol on plasma calcium and femoral bone structure in alligators (Alligator mississippiensis).

The effects of exogenous estradiol on plasma calcium and femoral bone structure were studied in young male and female alligators. Males and females responded in the same manner to estrogen treatment. Eight days after the initial injection, plasma calcium was significantly greater in experimentals than in controls. No changes in femoral bone structure were observed.

Alligators and Crocodiles↗
PubMed1986

A scanning electron-microscopic study of femoral bone surfaces from castrate rats treated with dichloromethylene biphosphonate.

This study compared SEM appearances of endosteal and periosteal surfaces of anorganic femoral diaphyses from three groups of adult male rats: (1) control; (2) castrate (osteoporotic), and (3) castrate + injections of dichloromethylene biphosphonate (Cl2 entrances; (2) area of vascular canal entrances; (3) number of osteoblast lacunae, and (4) percent area of bone surface types. Endosteal surfaces from untreated osteoporotic rats had significantly more osteoblast lacunae, larger vascular canal entrances, and less resting surface than those of the other groups. There were no differences in endosteal surfaces between controls and Cl2MBP-treated castrates. Periosteal surfaces demonstrated no significant differences in percent area of bone surface types between groups, untreated castrates had more osteoblast lacunae than other groups, and vascular canal entrances were smaller in castrate groups than in controls. Castrates treated with Cl2MBP had significantly fewer periosteal vascular canal entrances, and many canal entrances and osteoblast lacunae appeared to be plugged with mineral deposits when compared with the other groups. The results indicate that Cl2MBP treatment prevented endosteal bone surface changes that occurred with castration osteoporosis, and may have disrupted normal vascularization on periosteal surfaces.

Animals↗
PubMed1985

The effects of dichloromethylene biphosphonate on osteoporotic femora of adult castrate male rats.

In a previous study we reported that castration of adult male rats resulted in femoral osteoporosis 4 months later. The present study tested the effects of dichloromethylene biphosphonate (Cl2MBP, formerly Cl2MDP), a bone resorption inhibitor, on the development of osteoporosis in femora of adult castrated male rats. One-year-old male Holtzman rats were assigned to three groups: sham-operated controls; castrated-no treatment; castrated + Cl2MBP injections 3 times/week. The animals were sacrificed 4 months later. Femora from untreated castrated rats were osteoporotic, confirming our earlier study. Femora from Cl2MBP-treated castrates did not differ from those of controls and were significantly denser and more robust than those of untreated castrated rats. The results indicated that Cl2MBP treatment started immediately after castration prevented the development of femoral osteoporosis in adult castrated male rats.

Animals↗
PubMed1983

Effects of saltwater feeding and reduced food intake on femurs of domestic ducklings.

Seven-day-old domestic ducklings were assigned to groups and fed freshwater and food ad libitum (control), 1% NaCl and food ad libitum (stressed), or freshwater and only as much food as the stressed group ate (starved). Tissues were sampled after 3 and 7 days. Other groups of ducklings were fed freshwater and food ad libitum for 9 days (control), 1% NaCl and food ad libitum for 7 days followed by freshwater for 2 days (de-stressed), or freshwater and the same amount of food as the de-stressed group for 7 days followed by food ad libitum for 2 days (de-starved). Body weights were recorded and the femurs were analyzed. Univariate, multivariate, and allometric analyses clearly demonstrate that stressed and starved regimens influence femoral morphology differently. Stressing for 3 days reduced femoral ash and by 7 days had retarded femoral linear growth. Three days of starvation produced no apparent effect on the femur, but starvation for 7 days reduced the amount of femoral ash/femoral length. Furthermore, major differences between stressed and starved ducks disappeared after de-stressing for 2 days. Studies of bone growth and metabolism may benefit by using this avian model.

Animals↗
PubMed1982

The effects of castration on size and appearance of Sharpey's fibers of rat femurs: a scanning electron microscopic and microradiographic study.

Areas of Sharpey fiber bone from the proximal posterior diaphyseal surfaces of anorganic control and castrate osteopenic rat femurs were examined with the scanning electron microscope (SEM). The diameter of Sharpey fiber bundle insertion sites from castratre bone was significantly greater (P less than 0.001) than that from control bone. The fiber bundle insertions appeared as small pits and projections in control bone and as large pits in castrate bones. Microradiographs of cross sections of the Sharpey fiber bone revealed a greater (P less than 0.05) area of outer, lamellated periosteal bone in the castrates than in the controls, suggesting an accelerated bone apposition rate along castrate osteopenic femoral periosteal surfaces.

Animals↗
PubMed1982

Scanning electron microscopy of castrate rat bone.

The study describes the SEM appearances of endosteal and periosteal surfaces of anorganic femoral diaphyses from 16-month-old normal and castrate male rats. Different types of surfaces could be recognized in both groups. Percentage areas occupied by each surface type were analyzed with a Ladd Data Analyzing Digitizer. Endosteal surfaces were composed of significantly more (P less than 0.05) incompletely mineralized, forming surface and significantly less (P less than 0.05) completely mineralized, resting surface in castrates than in controls. Both endosteal and periosteal surfaces from experimental bone demonstrated significantly more (P less than 0.05) osteoblast lucunae than did control surfaces, and vascular canal entrances were significantly wider (P less than 0.001) on castrate endosteal surfaces than on control endosteal surfaces. There was a greater proportion of small nodule forming surface/large nodule forming surface in castrate endosteal bone than in control, and a greater proportion prolonged resting surface/fibrous resting surface in control periosteal bone than in castrate. The results indicate that, when viewed in the SEM, anorganic endosteal and periosteal bone surfaces from femoral diaphyses of old castrate male rats demonstrate appearances characteristic of changes in bone turnover that occur with osteoporosis.

Animals↗