Biomedical subjects

L S Kong

Publications and source records attributed to L S Kong.

5 recordsLinked to original sources

PubMed2002

A quantitative (stereological) study of the effects of experimental unilateral cryptorchidism and subsequent orchiopexy on spermatogenesis in adult rabbit testis.

The aim of this study was to examine the controversial effects of experimental unilateral cryptorchidism and subsequent orchiopexy on the number of germ cells and other morphometric characteristics of testicular and epididymal structures in adult rabbits. Unilateral cryptorchidism was induced in 11 mature male New Zealand white rabbits by returning one testis, together with the ipsilateral epididymis, to the abdominal cavity via a surgical procedure. After 3 months, testes and epididymides were removed from six animals (and from six age-matched control animals that did not undergo the surgery). Orchiopexy was performed on the five remaining animals and the testes and epididymides of these animals (and an additional six age-matched control animals) were removed 7 weeks later. A contemporary, unbiased and efficient stereological tool, the optical disector, was used to estimate the number of nuclei in the testis and epididymis using methacrylate-embedded sections of 25 micron in thickness. Cryptorchidism resulted in severe testicular atrophy and spermatogenic arrest: type A spermatogonia and Sertoli cells only were seen in the seminiferous epithelium, and the number of type A spermatogonia per testis was reduced by 84%. After orchiopexy, the testis remained atrophied and the number of type A spermatogonia returned to the near-normal range in four of five animals, but spermatogenesis was recovered only partially at the stage of early primary spermatocytes (one animal), late primary spermatocytes (two animals) or spermatids (one animal). In conclusion, cryptorchidism caused severe spermatogenic arrest that was potentially recoverable (in view of the restoration of the number of type A spermatogonia), but orchiopexy failed to induce full recovery of spermatogenesis.

Animals↗

PubMed1992

Idiopathic sudden hearing loss and disturbance of iron metabolism. A clinical survey of 426 cases.

The role of disturbances of the iron metabolism (DIM) in idiopathic sudden hearing loss (ISHL) was investigated in 426 patients with ISHL who received iron therapy, anti-DIM medication, vitamins, and a combined regimen in a randomized study which was stratified by stages and groups. Low concentrations of haemoglobin, serum iron, serum ferritin, and red cell basic ferritin as well as abnormal circadian variations in the serum iron level were observed. The results were significantly better in patients receiving iron therapy than in those receiving anti-DIM medication, vitamins, and the combined regimen. Hearing improvement was achieved in 53.26% of the patients whose treatment started later than 3 months after the onset of the disease. The clinical association of DIM and ISHL is discussed.

Adult↗

PubMed1991

Red cell basic ferritin concentration in sensorineural hearing loss.

Red cell basic ferritin (RCBF) was measured in 62 healthy subjects with normal hearing and 224 patients with different kinds of sensorineural hearing loss, compared with serum ferritin, haemoglobin, serum iron and circadian variation in the serum iron levels. The results showed that the RCBF concentrations in most kinds of sensorineural hearing loss were significantly lower than those in normal hearing status. It is conceivable that the RCBF assay can be used to evaluate the adequacy of iron stores that are useful in times of urgent iron needs and to diagnose relative iron deficiency in those patients with some other normal laboratory assays related to iron metabolism.

Adolescent↗

PubMed1991

Neuroendocrine evaluation in Kleine-Levin syndrome: evidence of reduced dopaminergic tone during periods of hypersomnolence.

A patient with Kleine-Levin syndrome had polysomnography and neuroendocrinological assays performed during asymptomatic (ASMP) and symptomatic (SMP) 24-hr periods. During the SMP, sleep data revealed poor nocturnal sleep efficiency, increased sleep fragmentation and reduced stages 3, 4 and rapid eye movement (REM). No sleep onset REM episodes were seen. Sleep staging in the ASMP was normal. Blood samples were obtained every 20 min and assayed for thyroid-stimulating hormone (TSH), cortisol (CORT), prolactin (PRL) and growth hormone (GH). Patterns of secretion, 24-hr mean and total integrated concentrations, and mean sleep period time values during the ASMP and SMP were compared. The mean 24-hr level of TSH was increased and GH decreased in the SMP. Comparing sleep period time in the SMP to the ASMP, values for TSH and PRL were increased and GH and CORT were reduced in the SMP. These hormone changes support the hypothesis that reduced hypothalamic dopaminergic tone is present in the SMP compared to the ASMP in Kleine-Levin patients.

Adult↗

PubMed1990

Dynamic observation on thyroid function in severe head injury.

The dynamic changes of thyroid hormone levels in patients with severe head injury were observed. The results showed that the serum thyroid hormone levels changed rapidly within several hours after the injury and the mean levels of serum total T3 and T4 (TT3, TT4) decreased while high reverse triiodothyronine (rT3) increased significantly. Serum TT3, TT4 and rT3 levels returned to normal gradually in 2 to 3 weeks after the injury in the surviving group, whereas serum total T4 gradually declined and rT3 steadily increased in the fatal group. The mean levels of serum TSH remained unchanged in both groups. Therefore, the use of the levels of serum thyroid hormones as adjuvant indices can be helpful in making pertinent judgements of the severity and prognosis of severe head injuries.

Adult↗