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C Hsu

Publications and source records attributed to C Hsu.

At least 19 recordsLinked to original sources
PubMed1992

Effects of anterior roof deafferentation on lordosis behavior and estrogen receptors in various brain regions of female rats.

This study investigated whether the estrogen receptors (ER), located at different brain areas and anterior pituitary (AP), changed after anterior roof deafferentation (ARD), and on the effects of facilitating the lordosis reflex in female rats. Female rats were ovariectomized and implanted with estradiol capsules. ARD or sham operation was performed with a Halász knife. All animals were tested for lordosis both before and after surgery. One day after the last test they were sacrificed. Cytosol and nuclear ER in the AP, medial preoptic area (MPOA), basal medial hypothalamus (BMH), amygdala (AMYG), septum (SEP), hippocampus (HPC), and cortex (CTX) were measured using an in vitro exchange assay. Rats with ARD showed significantly higher mean levels of lordosis quotient than the control and the sham groups before ARD surgery. An increase of both cytosol and nuclear ER in the BMH area compared to the control was observed, whereas the ER, in the SEP was reduced. ER in other areas were not affected by ARD. Serum estradiol and progesterone levels were not altered by the operation. These data suggest that the dorsal inhibitory pathway from the extrahypothalamus to the preoptic area and hypothalamus may modulate the estrogen receptor and the display of lordosis in female rats. Change of ER level in the BMH area may influence the hormonal sensitivity of lordosis in female rats.

Animals↗
PubMed1992

Improvement of sexual behavior in aged rats by p-chlorophenylalanine and methysergide.

The effects of methysergide, a serotonin antagonist, and p-chlorophenylalanine (PCPA), a serotonin synthesis blocker on the sexual behavior of intact old male rats at 19-23 months of age and female rats at 17-18 months of age were studied. Female rats with prolonged vaginal cornification and a lordosis quotient (LQ) of less than 50%, and male rats displaying no ejaculation were selected as experimental animals. The receptivity of aged female rats, but not the approach behavior to males nor proceptivity was improved by PCPA or methysergide. The LQ of intact aged female rats in non-exit tests was improved by the i.p. administration of 50 mg/kg B.W. of PCPA 2 to 4 hours prior to the sexual behavior test or 3 mg/kg B.W. of methysergide 4 hours prior to the test. Total mount frequency and mount latency of intact aged male rats were improved by the administration of methysergide (3 mg/kg B.W.), while total mount frequency and intromission latency were improved by the administration of PCPA (20 mg/kg B.W. for 4 days). The present results together with the finding from our previous study suggest that the increase of serotonin (5-HT) activity per se plays an important role in the decline of receptivity of aged female rats and the copulatory activity of aged male rats.

Aging↗
PubMed1992

[The effect of monosodium L-glutamate (MSG) treatment during neonatal period on the pineal function in young female rats].

The purpose of this study is to examine whether monosodium L-glutamate (MSG) influences the function of pinealocytes in female rats. MSG was administered at a does of 4 mg/g body weight to rat pups on days 1 and 3 postnatally. As the rats matured, sexual receptivity as well as proceptivity were observed by testing the lordosis quotient (LQ), rejection quotient (RQ) and solicitation. Pineal function was estimated by measuring the serum level of melatonin and the activity of protein kinase A (PKA) in the pineal gland. Blood samples were withdrawn at light and dark phases for four consecutive days, respectively. The serum concentration of melatonin was determined by radioimmunoassay and the data of each phase were pooled together. The results showed that both the receptivity and proceptivity of MSG-treated female rats were significantly lower than that of the control ones. Melatonin levels during the dark phase were significantly higher than those during the light phase in both control and MSG-treated groups, but whenever in the light or dark phase, the levels of melatonin were the same in both groups. There was no significant difference in PKA activity in the pineal gland between the control and MSG-treated group. These results indicate that MSG used as a neurotoxin to induce hypogonadal status affected neither the PKA activity of pineal gland nor the serum level of melatonin in young female rats. Thus, the decrease in receptivity and proceptivity of MSG-treated female rats was not caused by the alteration of pineal function.

Animals↗
PubMed1992

[The mechanism of the pineal gland in inhibiting sexual receptivity of female rats: (II) Does it concern progesterone?].

The present study was designed to find the role of progesterone in modulating the effect of pineal gland upon reproductive behavior in the female rat. Monosodium L-glutamate (MSG) was used as a neurotoxin to induce hypogonadal function. In the first part of the experiment, rats were divided into four groups: (1) normal, (2) pinealectomized (Px), (3) MSG-treated (MSG), and (4) pinealectomized MSG-treated (Px-MSG), as immature rats became mature, the IEC (Incidence of Estrous Cycle) in each group was determined by vaginal smear for three weeks. Serum samples for estimating the levels of progesterone were collected at estrous. Then, ovariectomy was performed. Two weeks later, estradiol was primed for three days following progesterone administration and sexual receptivity as well as solicitation were observed. The results showed that, the serum progesterone levels and IEC of Px-MSG rats were significantly higher than that of the MSG group. In addition, Px and Px-MSG rats showed a higher sexual receptivity than normal and MSG rats, respectively. In the second part of the experiment, rats were divided into two groups: (1) normal and (2) Px. All rats were ovariectomized at 2.5 months of age and implanted with a 2-mm 20% estradiol benzoate-filled silastic capsule. Then, sexual receptivity to various doses of progesterone (0, 0.02, 0.1, 0.5 mg/rat) were observed. The results showed that receptivity of Px rats was significantly higher than that of the normal ones in a dose-dependent manner. It is concluded that pineal gland plays an important role in the regulation of ovary function as well as sexual receptivity in female rats. Also, progesterone may be one of the factors modulating the effect of pineal gland on sexual receptivity.

Animals↗
PubMed1992

Therapeutic potential for adenosine receptor activation in ischemic brain injury.

The present report reviews the biochemical and physiological responses to adenosine receptor activation and how these responses underlie the ability of adenosine to couple energy demand with energy supply. In addition, activation of adenosine receptors pharmacologically is shown to initiate various reactions which could be responsible for the observed adenosine-mediated attenuation of the neuropathological consequences of brain ischemia. Also reported is the extent to which side effects such as hypothermia can contribute to the observed efficacy of adenosine agonist administration in the small animal model of ischemia. Data from various in vitro and in vivo ischemia studies is presented showing that neuroprotection can be achieved following pharmacological activation of adenosine receptors either through agonists with high affinity for A1 adenosine receptors or drugs which potentiate endogenous adenosine levels. In general the data support utilization of adenosine receptor activation as a means of attenuating ischemic brain damage.

Adenosine↗
PubMed1991

[The action mechanism of the pineal gland in inhibiting sexual receptivity of female rats: (I). Is it concerned with the extrahypothalamic inhibitory pathway?].

Monosodium L-glutamate (MSG), as a neurotoxin, was administered subcutaneously at a dose of 4 mg/g body weight to rat pups on days 1 and 3 postnatally. The sexual receptivity expressed as lordosis quotient (LQ) in MSG-treated female rats (2.5 months old) was significantly lower than that of the normal female ones, and this poor sexual receptivity of MSG-treated females could be improved by pinealectomy at the age of six weeks. In order to investigate the relationship between the inhibitory role of the pineal gland and the extrahypothalamic inhibitory pathway, normal control and MSG-treated rats were ovariectomized and implanted subcutaneously with estradiol capsule (20% estradiol benzoate, in 2mm silastic tube) at the age of 2.5 months. Three days after implantation, sexual receptivity was observed. Then, the anterior roof deafferentation (ARD) was preformed one week later and the sexual receptivity in both groups was compared again. The results showed that there was no significant difference of the lordosis response between the MSG-treated and the control groups before ARD, and the level of restoration by ARD in LQ of MSG-treated rats was similar to that of the control group. It seems that the extrahypothalamic inhibitory pathway of sexual receptivity may not be influenced by neonatal MSG-treatment. Our previous results indicated that the behavioral sensitivity to estradiol was altered by ARD. However, in the present study, the lordosis responses of MSG-treated and pinealectomized female rats were not significantly different from that of the control group after ovariectomy and exogenous estradiol implantation. This means that the behavioral sensitivities to estradiol were not changed by MSG-treatment or pinealectomy.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Efficacy of fine-needle aspiration and sampling of lymph nodes in 1,484 Chinese patients.

A retrospective study of 1,855 fine-needle aspirations of the lymph node (LN) from 1,484 Chinese patients in Queen Mary Hospital over a period of 11.5 yr (January 1, 1976, to June 30, 1987) was reviewed and analyzed. Positive cytologic results diagnosed malignancies in 49.3%. Sensitivity and specificity of cytology reached 95% and 96.5%, respectively. The order of frequency of the metastatic tumors according to primary sites was analyzed. The most common metastatic carcinomas in various groups of LNs were nasopharyngeal carcinoma in the cervical LN, breast carcinoma in the axillary LN, and cervical carcinoma in both the groin and pelvic LNs. Tuberculosis (TB) is an important differential diagnosis; FNAC showed a sensitivity of 76.9% in the detection of TB lymphadenopathy.

Adolescent↗
PubMed1990

Efficacy of fine needle aspiration cytology in the diagnosis of tuberculous cervical lymphadenopathy.

The results of a consecutive series of 1,349 fine needle aspiration (FNA) biopsies from the head and neck region of 1,193 patients has been reviewed in order to evaluate the efficacy of this method in the diagnosis of tuberculous lymphadenopathy (TBLN). Of the 108 patients whose fine needle aspiration cytology (FNAC) showed granulomatous changes, 68 had subsequent surgery and histological confirmation of the cytological appearance. Sixty-three had TBLN, thus the specificity of FNAC was 93 per cent in diagnosing tuberculous related granulomatous lymphadenopathy. One false positive FNAC was reported histologically to be metastatic mucoepidermal carcinoma. Of the 1,193 patients, 90 patients had subsequently TBLN confirmed histologically. Of these 90 patients, FNA from 69 showed granulomatous changes or acid fast bacilli (AFB), thus the sensitivity of FNAC in detecting tuberculous lymphadenopathy was 77 per cent. Fifty-two cytological smears were stained for acid fast bacilli. Nineteen (37 per cent) contained AFB. It is evident from this review that FNAC is an efficient way to detect cervical tuberculous lymphadenopathy.

Biopsy, Needle↗
PubMed1990

Human papillomavirus infection in the cervix of pregnant females in Hong Kong.

Routine cytological examination and HPV-DNA probing were performed on cervical cells obtained from 215 pregnant Chinese females. The procedure utilized the specific binding of a mixture of complementary [32P]-labelled RNA probes to membrane-bound target HPV DNA types 6, 11, 16, 18, 31, 33 and 35. Positive results for HPV-DNA were obtained in 11/215 (5%) of the cases. The cervical smears were routinely processed and in 3/215 (1.5%) cases a cytological diagnosis of wart virus infection was made. All three were included in the 11 probe-positive cases. Using similar molecular biological techniques, pregnant Western females have an incidence of HPV infection of the cervix which is up to five times that of the present series. This is an unexpected finding in view of the fact that the incidence of cervical cancer is higher in Chinese women than American women.

Female↗
PubMed1990

Influence of pinealectomy on sexual behavior of normal and monosodium L-glutamate-treated rats.

Subcutaneous injections of monosodium L-glutamate (MSG) were administered, as a neurotoxin, at a dose of 4 mg/g body weight to rat pups on days 1 and 3 postnatally. Pinealectomy was performed at 6 weeks of age, and animals were allowed to mature. The intact MSG-treated rats showed a decrease of lordosis quotient in females and a reduction of ejaculation frequency and an increase in mount frequency in males. Pinealectomy caused no significant improvement on sexual behavior of the saline-treated normal rats, but it caused a marked improvement of the sexual receptivity in MSG-treated female rats and reinstated ejaculation in MSG-treated males. The circulatory sex steroid levels, estrogen in females and androgen in males, were not significantly different between the intact and pinealectomized MSG-treated groups in the respective sexes, whereas the progesterone level in females was significantly elevated in the pinealectomized MSG-treated group compared with the intact MSG-treated group. These findings suggest that the pineal gland plays an inhibitory role on the sexual behavior of MSG-treated rats and the improvement of sexual behavior following pinealectomy may be dependent on certain mechanisms other than the actions of circulatory androgens or estrogens.

Analysis of Variance↗
PubMed1989

Escherichia coli K-12 cell-cell interactions seen by time-lapse video.

The high degree of organization in mature bacterial colonies suggests specific interactions between the cells during colony development. We have used time-lapse video microscopy to find evidence for cell-cell interactions. In its initial stages, Escherichia coli K-12 colony morphogenesis displayed control of the geometry of cell growth and involved intimate side-by-side associations. When microcolonies developed from isolated single bacteria, a directed process of elongation and division resulted in the appearance of a symmetrical four-cell array. When growth began with separate but nearby bacteria, the daughters of different cells elongated towards each other and also lined up side by side. Interactions between microcolonies containing several hundred or more bacteria were visible several hours later. Control of cell morphogenesis at later stages of microcolony development was strain specific. These results show that E. coli K-12 cells respond to each other and adjust their cellular morphogenesis to form multicellular groups as they proliferate on agar.

Cell Division↗
PubMed1988

Fine needle aspiration biopsy of tuberculous cervical lymphadenopathy.

Fine needle aspiration biopsies of 42 histologically confirmed tuberculous cervical lesions were studied. Thirty-four patients had subsequent excision of cervical lymph nodes and eight had incision and drainage of cervical abscesses. All aspirates except two (which were inadequate) were satisfactory for diagnosis and contained inflammatory cells. Twenty-seven smears revealed cells typical of granulomatous lymphadenopathy, that is, epithelioid and multinucleated giant cells. Of all aspirates, 17 smears had bacteriological staining by Ziehl-Nielsen technique, nine of which (53%) were positive for acid-fast bacilli. An aspiration biopsy diagnosis of granulomatous or tuberculous cervical lymphadenopathy was made in 30 patients (71%). In regions where mycobacterial infection is common, the presence of granulomatous changes in lymph node aspirates is highly suggestive of tuberculosis. When the aspirates contain purulent material or when tuberculosis is suspected, staining and culture for mycobacteria should be performed. FNA biopsy is a sensitive, specific and cost-effective way to diagnose tuberculous cervical lymphadenopathy and is recommended.

Adolescent↗
PubMed1987

Cytologic detection of malignancy in pleural effusion: a review of 5,255 samples from 3,811 patients.

A retrospective analysis of 5,255 pleural effusion specimens from 3,811 patients was undertaken to determine the accuracy of cytopathologic correlation with pleural biopsy, the detection rate of malignancy by cytology, and the frequency distribution of malignant effusions according to age group. The cytopathologic correlation was 96.5% accurate, with 0.1% false-positive results and 0.18% false-negative results by cytology. The sensitivity of cytologic detections was 6.7% higher than that of pleural biopsy. Frequency analysis showed that the incidence of carcinoma of the lung, the most common cause of malignant effusion, is not sex based. Adenocarcinoma of the lung was the most frequent type of malignancy found in pleural effusions. It represented 79% of lung carcinomas that metastasized to pleura, accounting for 40% of all malignant pleural effusions. In young adults, lymphoreticular malignancies were the most common cause of malignant effusions.

Adenocarcinoma↗
PubMed1987

Frequency of "blue bodies" in pulmonary cytology specimens.

To determine the frequency of occurrence of "blue bodies" (BBs), 2,010 pulmonary cytology specimens (1,403 sputum and 607 bronchial specimens) from 1985 were reviewed. The smears were examined microscopically by transmitted and polarized light. BBs were extracellular structures, occurring most commonly in clusters but sometimes conglomerated. With Papanicolaou stain, they had a characteristic birefringent laminated brown core and a nonbirefringent blue rim. Chemical microanalysis and energy-dispersive x-ray analysis revealed that their chemical composition was calcium carbonate. A total of 233 specimens contained BBs, with a frequency of 10.5% in bronchial specimens and 12% in sputum. Only 8.6% of the BBs had co-existent pulmonary malignancy. We concluded that BBs were common structures in pulmonary cytology and were not associated with pulmonary malignancy or pulmonary fibrosis in our series. They must be distinguished from contaminants, staining artifacts, and parasitic ova.

Adolescent↗
PubMed1987

Smoking, passive smoking and histological types in lung cancer in Hong Kong Chinese women.

In a case control study in Hong Kong, 445 cases of Chinese female lung cancer patients all confirmed pathologically were compared with 445 Chinese female healthy neighbourhood controls matched for age. The predominant histological type was adenocarcinoma (47.2%). The relative risk (RR) in ever-smokers was 3.81 (P less than 0.001, 95% CI = 2.86, 5.08). The RRs were statistically significantly raised for all major cell types with significant trends between RR and amount of tobacco smoked daily. Among never smoking women, RR for passive smoking due to a smoking husband was 1.65 (P less than 0.01, 95% CI = 1.16, 2.35) with a significant trend between RR and amount smoked daily by the husband. When broken down by cell types, the numbers were substantial only for adenocarcinoma (RR = 2.12, P less than 0.01, 95% CI = 1.32, 3.39) with a significant trend between RR and amount smoked daily by the husband. The results suggest that passive smoking is a risk factor for lung cancer, particularly adenocarcinoma in Hong Kong Chinese women who never smoked.

Adenocarcinoma↗
PubMed1987

Diagnosis of endometrial carcinoma by histopathological examination of the endometrial aspirate by the Curity-Isaacs sampler.

The Curity-Isaacs Endometrial Cell (CIEC) sampler was used for endometrial tissue and cell sampling in 230 patients before dilatation and curettage to determine the efficacy of its use as an outpatient endometrial sampler. Its use was found to be safe and without complication. It could be easily inserted into the uterine cavity in 92.0% of patients and did not cause undue discomfort in 88.9% of them. Using histopathological diagnostic techniques, there was 100% accuracy in the diagnosis of endometrial carcinoma. However, it was found that diagnostic accuracy of endometrial hyperplasia was only 33.3%. It is suggested that the CIEC sampler could be used as a first-line diagnostic procedure to exclude endometrial carcinoma in patients with abnormal vaginal bleeding.

Adult↗