Biomedical subjects

Zhi-ming Cai

Publications and source records attributed to Zhi-ming Cai.

15 recordsLinked to original sources

PubMed2006

[Identification of human testicular spermatogenic cells at different stages].

OBJECTIVE: To establish the method to identify human testicular spermatogenic cells. METHODS: Cells were dispersed by mechanic disintegration on testicular biopsy samples of obstructive azoospermic patients. Diff-Quik staining was applied to mixed cell smears. Live cells were observed under inverted microscope equipped with Hoffman modulation contrast optics, and classified according to their morphology. Chromogenic in situ hybridization (CISH) using chromosome 17 centromere probe and anti-c-kit immunocytochemistry staining were applied to classified cell smears. RESULTS: Sertoli cell, primary pachytene spermatocyte (PPS), spermatogonia, round spermatid were the main four round cell groups that can be classified under Hoffman optics. In CISH, Sertoli cell, PPS and spermatogonia displayed 2 centromere signals, while round spermatid and elongated spermatid/sperm displayed 1 centromere signal. In immunocytochemistry staining, PPS and spermatogonia displayed positive staining, while Sertoli cell, round spermatid and sperm displayed negative staining. CONCLUSION: Dispersed human testicular cells displayed different characteristics in live/staining morphology, ploidy analysis, cell surface membrane antigen expression. All of these methods can be chosen to identify human testicular spermatogenic cells at different stages, while cell morphology classifying under Hoffman optics is a simple and effective method for live cell identification.

Adult↗

PubMed2006

[Expression of hypoxia inducible factor-1alpha and glucose transporter protein 1 in renal and bladder cancers and the clinical significance thereof].

OBJECTIVE: To investigate the protein expression of hypoxia inducible factor-1alpha (HIF-1alpha) and glucose transporter protein 1 (Glut-1) in renal cancer and bladder cancers and the clinical significance thereof. METHODS: TransAMTMELISA was used to detect the protein expression of HIF-1alpha in the tissue sections from 25 patients with bladder transitional cell carcinoma (TCC) and 16 patients with renal clear cell carcinoma resected during operation and small amounts of normal renal and bladder tissues far from the cancer tissue resected simultaneously. Immunohistochemistry was used to detect the protein expression of Glut-1 in tissue sections from 58 patients with bladder carcinoma transitional cell carcinoma and 38 patients with renal clear cell carcinoma resected during operation. 16 specimens of normal bladder and 16 specimens of normal renal tissue were obtained from the patients with other diseases who underwent operation during the same period to be used as controls. Follow-up was conducted for more than 2 years for all patients. RESULTS: The protein expression of HIF-1alpha in the tissue of renal clear cell carcinoma was 3.38 +/- 1.71 microg/well, significantly higher than that in the tissue near the cancer (2.23 +/- 1.07 microg/well, P < 0.01). The protein expression of HIF-1alpha in the bladder TCC tissue was 2.69 +/- 1.34 microg/well, not significantly different from that in the tissue near the cancer (248 +/- 1.28 microg/well, P = 0.60). Protein expression of Glut-1 was not detected in the normal renal and bladder tissues, however, was significantly higher in the bladder TCC and renal clear cell carcinoma tissues. The positive rate of Glut-1 in the bladder TCC tissue was 77.90% (45/58). The positive rates of Glut-1 in the tissues of bladder TCC tissue, grades G1, G2, and G3 were 66.7%, 89.1%, and 53.3%. (P = 0.29), showing the correlation of Glut-1 expression with the grading of cancer. The positive rate of Glut-1 in the superficial TCC was 83.9%, not significantly different from that of the invasive TVV (70.4%, P = 0.90), showing that the Glut-1 is not correlated with the cancer staging. Nineteen of the 31 cases of superficial TCC showed recurrence within 2 years, however, the protein expression of Glut-1 rate was not significantly different between those with recurrence and those without recurrence (P = 0.90), showing that the protein expression of Glut-1 is not correlated with the recurrence of TCC. The protein expression of Glut-1 in the renal clear cell carcinoma was at a rate of 86.9% (33/38), however, it was not correlated with the grade and stage of the cancer. CONCLUSION: The protein expression of HIF-1alpha is strongly associated with the neoplastic progression of renal clear cell carcinoma, but its role in the development of bladder TCC is not clear yet. The protein expression of Glut-1 is strongly associated with the neoplastic progression of bladder TCC and renal clear cell carcinoma.

Adult↗

PubMed2006

[Functional expression of adenylyl cyclase and phosphodiesterase in ejaculated human spermatozoa].

OBJECTIVE: To compare the differences of expressions of adenylyl cyclase (AC) and phosphodiesterase (PDE) in ejaculated spermatozoa between healthy volunteers and the patients with asthenospermia. METHODS: Ejaculated spermatozoa were collected from healthy volunteers and the patients with asthenospermia. Reverse transcription polymerase chain reaction (RT-PCR) was used to detect mRNA expression of AC and PDE subtypes in human spermatozoa. The concentrations of cAMP and cGMP in the samples were detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: Compared with healthy volunteers, expression of sAC mRNA and concentration of cAMP were significantly decreased in the patients with asthenospermia (P < 0.01) , while the expression of PDE4C mRNA was significantly increased at the same time (P <0.01). There were no marked differences in the expression of ACIII mRNA and concentration of cGMP between the two groups. CONCLUSION: The sAC down-regulation and PDE4C up-regulation are possible reasons for asthenospermia.

Adenylyl Cyclases↗

PubMed2006

[In-vitro differentiation of human testicular round spermatids to elongating spermatids].

OBJECTIVE: To investigate the differentiation of human testicular spermatogenic cells during in vitro culture. METHODS: Testicular cells of obstructive azoospermic patients' testis biopsies were dispersed employing mechanic methods. Then, (1) mixed testicular cells were applied to in vitro culture, and changes of the ratio of elongating spermatids and all round cells were analyzed during mixed cell culture; (2) round spermatids were picked up from the mixed cells employing micromanipulator, followed by differentiation of the isolated round spermatids during microdrop culture. RESULTS: The ratio of the elongating spermatids increased significantly (P < 0.05) after 24 hours of mixed cell culture in HTF medium supplemented with FSH and testosterone. During single round spermatid culture, transformation of the round spermatid to elongating spermatid with newly formed flagellum was observed, and the transformation ratio within 48 hours of microdrop culture was 3.54%. The differentiation of human testicular spermatogenic cells cultured in Vero cell conditioned medium was similar to that cultured in HTF medium. CONCLUSION: Human testicular round spermatids can differentiate to elongating spermatids during in vitro culture. Vero cell conditioned medium does not promote the differentiation of human testicular round spermatids to elongating spermatids.

Animals↗

PubMed2006

[Research progress in ectopic grafting of testicular tissues].

Since Nature published the first report in 2002 on using immunodeficient mice as recipients and allogeneous or heterogeneous testes as donor tissues to study the ectopic development of spermatogenic cells, the technique has been widely applied in various species (including human). In comparison with other in vitro maturation methods for male germ cells, testicular allografting or xenografting technique has such advantages as similar environment for the development of germ cells in physiological conditions, and better reproducibility. Up to now, sperm has been successfully produced by this technique from the testicular tisues of the immature mouse, hamster, cat, rabbit, pig, goat, bovine and rhesus monkey, and their offspring have even been generated by ICSI technique using the mouse and rabbit sperm derived from testis grafts. This article comprehensively reviews the development of the technique by discussing the influencing factors on the germ cell development in grafts including the variety and age of donors, the sex, integrity and immunity of recipients, the graft location and grafting time. And the applications of the technique and the existing problems are discussed as well.

Animals↗

PubMed2005

[Hormone regulation of the expression of vascular endothelial growth factor and its receptors in mouse uterus].

OBJECTIVE: To investigate the effects of estrogen and progesterone on the expression of vascular endothelial growth factor (VEGF) and its receptors (VEGFR) in mouse uterus. METHODS: 3-week-old immature female mice were randomly divided into 7 groups and treated with corn oil, estradiol (E2) of 1.5, 3.0, 10, 25 ng, progesterone (P) of 100 microg and (E2 10 ng + P 100 microg)/mouse, respectively. After the treatment for 48 h, mouse uterus was collected to isolate total RNA. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the expression of mRNA isoforms of VEGF and its receptors in mouse uterus. RESULTS: Compared with control, both E2 and P significantly increased the expression of VEGF164 and VEGF120 mRNA in mouse uterus. The expression of VEGFR2 mRNA, not VEGF1 mRNA, was decreased by E2 treatment in a dose-independent manner. CONCLUSION: Both estradiol and progesterone up-regulated the expression of VEGF, but estradiol down-regulated the expression of VEGFR2 in mouse uterus.

Animals↗

PubMed2005

[A genetic study on microdeletion of azoospermia factor region on Y chromosome of azoospermia and oligozoospermia patients].

OBJECTIVE: To investigate the genetic causes of azoospermia and severe oligozoospermia. METHODS: Cytogenetic analysis and multiplex polymerase chain reaction(PCR) analysis were done on the 148 patients with azoospermia and serious oligozoospermia. RESULTS: Eleven of the 148(7.4%) cases showed microdeletion of at least one STS. In fifteen STS of AZFa, AZFb,AZFd, AZFc, thirteen STS, eleven STS,two STS and one STS microdeletion were found in each case respectively, including two with 12 STS, five with 5 STS microdeletion.Seven cases had chromosomal morphologic changes(4.7%),four had deletion and one had deletion with translocation of long arm on Y chromosome. One had enlarged region one band two(q12) on long arm of Y chromosome and one had reciprocal translocation of autosomes. CONCLUSION: The findings indicated that AZF microdeletion and chromosomal abnormality should be important causes of male infertility.

Azoospermia↗

PubMed2005

[Effect of benzene on sperm DNA].

OBJECTIVE: To assess the effect of benzene on sperm DNA. METHODS: Twenty-seven workers exposed to benzene for over two years were included in the experiment group and 35 unexposed ones were chosen as controls. Damage by benzene on sperm DNA was detected by modified single cell gel electrophoresis (SCGE). RESULTS: The benzene concentration in the air of the workplace of the exposed workers was (86.49 +/- 2.83) mg/m3, twice that of the national maximum allowance (40 mg/cm3). Urinary, trans-muconic acid in the exposed group was (1.40 +/- 0.62) mg/L (n = 27), significantly higher than that of the controls [(0.82) +/- 0.16) mg/L, n = 35]. After SCGE, the percentage of head DNA in the exposed group [(70.18% +/- 7.36%, n = 13 ] was significantly lower than that of the controls (90.62% +/- 2.94%, n = 16), P < 0.001. CONCLUSION: Higher concentration of benzene could cause damage to the sperm DNA of the workers exposed to it.

Adult↗

PubMed2005

[DNA microarray and its application in andrological research].

This article briefly retrospect the development of microarray, introduces the basic working procedures and the current challenges of DNA microarray, and reviews its application to andrological research, as on the testis, spermatogenic cells, epididymis and sperm. We hope it could play a directive role in the studies of male infertility.

Andrology↗

PubMed2005

[Using multiplex PCR to analyze the breakpoint of a severe Y-chromosome deletion].

OBJECTIVE: To elucidate the relationship between azoospermia factor(AZF) microdeletion of Y chromosome and azoospermia, the exact breakpoint of a severe Y-chromosome deletion was determined according to the physical map of AZF. METHODS: Multiplex polymerase chain reaction was used to amplify fifteen sequence tagged sites (STS), namely sY82, sY84, sY86 in AZFa, sY124, sY127, sY128, sY133, sY134, sY143 in AZFb, sY239, sY242 sY254, sY255 in AZFc, and sY145, sY152 in AZFd; sex-determining region Y(SRY) was taken as an internal control. And then sY82,sY86,sY85,sY84 were further analyzed using the sample of the patient who had Y-chromosome deletion by G band analysis to map the breakpoint at molecular level. RESULTS: All 15 STS and sY85 were amplified in positive control while only sY82, sY86 were amplified in the clinical sample, thus the breakpoint was found to be between sY86 and sY85. CONCLUSION: This study on the patient provided the direct biomolecular evidence of the exact breakpoint of the severe Y-chromosome deletion and established the deletion map of acrocentric chromosome. It also proved that the patient's azoospermia was due to the deletion of AZF.

Azoospermia↗

PubMed2004

[Clinical analysis of ultrasound-guided embryo transfer after in-vitro fertilization].

OBJECTIVE: To investigate whether ultrasound (US) guided embryo transfer could improve pregnancy rates. METHODS: A prospective randomized trial was conducted to compare embryo transfer under abdominal US guidance (n = 178) with traditional embryo transfer (n = 152). RESULTS: The clinical pregnancy rate was 37.1% (66/178) in the US group compared with 25.0% (38/152) in the traditional group (P < 0.05). CONCLUSIONS: US guided embryo transfer after in vitro fertilization increased pregnancy and implantation rates. It is suggested that embryo transfer should be performed under ultrasound guidance.

Adult↗

PubMed2004

[A cytogenetic and molecular genetic study on microdeletion of AZF region on Y chromosome].

OBJECTIVE: To study the morphology of Y chromosome and microdeletion of the correlated specific azoospermia factor(AZF) region on Y chromosome in cases of azoospermia and to identify the genetic diagnosis made for male infertility patients. METHODS: Peripheral blood samples were taken from two patients with azoospermia, and then were examined by use of G banding, C banding cytogenetic analysis and multiplex polymerase chain reaction (PCR) microdeletion analysis. RESULTS: The karyotypes of the two cases were 45, X, -Y, -22, +der(Y)t(Y;22)(q11.2;q11.2) and 46, XY, del(Y)(q11.2) respectively. In 12 sequence-tagged sites(STS) of AZFa, AZFb, AZFd, AZFc, only one was detected in the first case and two were detected in the other case. CONCLUSION: The cytogenetic analysis and the detection of AZF microdeletion on Y chromosome are essential to the final genetic diagnosis to be made for male infertility patients.

Chromosome Deletion↗

PubMed2004

[Experimental and clinical study on functional restoration of the penis with large partial defect].

OBJECTIVE: To investigate the effective restoration method in penile partial defect. METHODS: To measure the thickness of suspensory ligaments on cadavers; To find the relationship between inferior pubic ramus and corpora cavernosa crus through corpora cavernosa angiography and ultrasonic scanning. The procedure of restoration was based on the use of dissection of the suspensory ligaments and part of crus, and the local fat flap had been transferred to fill the front space of symphysis ossium pubi. Various flaps were designed as coverage material. Penis residual stump was advanced to anterior portion of the newly restoration penile body as "glans"; To take full layer skin of penis from post-operating patients to observe neurofibril regeneration by light microscopy, electron microscopy and scanning electron microscopy; To determine sensation recovery by physical examination; To check erectile function with NEVA System. RESULTS: The whole suspensory ligaments thickness was 7.66 cm in average on 30 cadavers (60 sides). The crus were attached to bilateral inferior pubic ramus respectively, and distal reached the middle of inferior pubic ramus by corpora cavernosa angiography. In 14 health men by ultrasonic scanning, 6.60 cm in average from root of external penis to location of deep artery penis entered corpora cavernosa. Forty patients had been operated with the above methods. In the cases, the length of the penis varied from 0.5-4.0 cm in the flaccid, 2.0-6.0 cm in erect state before operation to 5.0-8.5 cm in the flaccid, 7.0-12.5 cm in erect state after operation. Twenty-eight cases had been followed up for more than one year, and 23 patients married with acceptable sexual life, eighteen men had successfully produced their next generations. The regenerative neurofibril could be seen under light microscope, immunohistochemistry marker, scanning and transmission electron microscope. The penis presented normal pain and touch feeling in the post-operating cases. The results showed that there was similar erectile ability of a normal male in the follow-up patients. CONCLUSION: With these basic and clinical researches, the restoration of penis tends to have a better appearance and function. It's a more optimal method compared with conventional procedures. The results have also provided valuable data for further study in related fields.

Adult↗

PubMed2004

[Establishment of animal model for in vitro spermatogenesis by heterotopic grafting of neonatal mouse testis].

OBJECTIVE: To establish an in vitro model for the development of mouse spermatogenic cells into sperm by using the immunodefective mouse as the incubator. METHODS: Tissue grafting was performed using testis from 1-2 days old Kun-ming mice as donor tissue and immunodefective mice as recipients; the expression of TESK1 mRNA in grafts was determined by RT-PCR and the spermatogenesis further observed with histological analysis of grafts. RESULTS: Molecular biological and histological analyses showed that grafts post-grafting not only expressed TESK1 mRNA as in normal mouse testis, but also exhibited similarities in the structure of seminiferous tubules and component of spermatogenic cells, including sperms. CONCLUSION: Spermatogenic cells heterotopically grafted in vitro could continuously grow and complete spermatogenesis and finally develop into sperm.

Animals↗

PubMed2003

[Penis reconstruction with sensation and erectile function maintained (report of 40 cases)].

OBJECTIVE: To reconstruct a penis with sensation and erectile function maintained by corpora cavernosa lengthening and skin flap transferring in the penis defect cases. METHODS: The procedure was based on the use of releasing the suspensory ligaments and part of crus, various flaps were designed as coverage material. Penis residual stump was advanced to anterior portion of the newly reconstruction penile body as "glans". RESULTS: 40 patients with penis defect have been operated by the above methods. In the cases, length of the penis varied from 0.5-4.0 cm in the flaccid, 1.5-5.0 cm in erect state before operation. And after operation, it turned to 5.0-8.5 cm in the flaccid, 7.0-12.5 cm in erect state. Most of the patients recovered gross tactile sensation and had satisfactory erectile function. CONCLUSION: With this method, the reconstructed penis tends to have a better appearance and function. It's a more optimal method compared with the conventional operation.

Adult↗