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Biomedical subjects

Takeshi Maruo

Publications and source records attributed to Takeshi Maruo.

At least 55 records · Page 3Linked to original sources

Effect of a kink in unilateral pulmonary artery anastomosis on velocities of blood flow through bilateral pulmonary vein anastomoses in living-donor lobar lung transplantation.

Intraoperative transesophageal echocardiography is generally performed to detect vascular complications during lung transplantation. We report a case with a kink in pulmonary artery (PA) anastomosis suggested by an abnormal flow profile of pulmonary vein (PV) anastomoses during living-donor lobar lung transplantation. During the transplantation, velocity of blood flow through the right PV anastomosis showed abnormal elevation. Then, the patient's PA pressure elevated abnormally and a kink in the left PA anastomosis was found. Careful monitoring of PV anastomoses may enable detection of not only an abnormality of PV anastomoses but also that of PA anastomoses, especially in living-donor lobar lung transplantation.

Adult↗

Differences between flow profiles of pulmonary vein anastomoses affected by peripheral atelectasis in cadaveric and bilateral living-donor lobar lung transplantations.

We report two cases of peripheral atelectasis during cadaveric and living-donor lobar lung transplantation, which had different effects on the flow profile of pulmonary vein (PV) anastomoses. In the patient who underwent living-donor lobar lung transplantation, we detected the increase in the velocity of blood flow through the left PV anastomosis by intraoperative transesophageal echocardiography. Then peripheral atelectasis occurred in the transplanted left lung lobe. On the other hand, in the patient who underwent cadaveric bilateral lung transplantation, peripheral atelectasis occurred, but no changes in velocities of blood flow through PV anastomoses were detected by intraoperative transesophageal echocardiography. This difference may have been caused by the difference in sizes of pulmonary beds of transplanted grafts. These findings indicate the necessity of careful monitoring of PV anastomoses, especially in cases of living-donor lobar lung transplantation.

Adult↗

Polymorphisms in the estrogen receptor beta gene but not estrogen receptor alpha gene affect the risk of developing endometriosis in a Japanese population.

OBJECTIVE: To determine whether polymorphisms in the estrogen receptor (ER) alpha and beta genes are associated with endometriosis in a Japanese population. DESIGN: Association study. SETTING: University hospital. PATIENT(S): Japanese women diagnosed with endometriosis by laparotomy or laparoscopy. INTERVENTION(S): Determination of polymorphisms in the ERalpha and ERbeta genes was performed by polymerase chain reaction restriction fragment-length polymorphism analysis in 132 affected women and 182 controls. MAIN OUTCOME MEASURE(S): Frequency and distribution of AluI and RsaI polymorphisms in ERbeta gene and of PvuII and XbaI polymorphisms in ERalpha gene. RESULT(S): No significant differences in the frequency of either AluI and RsaI polymorphisms in the ERbeta gene or of XbaI and PvuII polymorphisms in the ERalpha gene were found between endometriosis patients and controls. However, a positive association was noted between the AluI polymorphism in the ERbeta gene and stage IV endometriosis patients in the population studied. CONCLUSION(S): The AluI polymorphism in the ERbeta gene is associated with an increased risk of stage IV endometriosis in a Japanese population.

Asian People↗

No association of endometriosis with glutathione S-transferase M1 and T1 null mutations in a Japanese population.

OBJECTIVE: Endometriosis is inherited as a complex trait, which means that multiple susceptibility genes interact with each other and with environmental factors to produce the phenotype. We investigated the frequency of glutathione S-transferase M1 and T1 (GSTM1 and GSTT1) null mutations in women with endometriosis in a Japanese population. METHODS: One hundred fourteen unrelated women with endometriosis were enrolled. Samples of umbilical cord blood obtained from 179 female newborn infants were used as population controls. Genomic DNA isolated from endometriosis patients and controls were subjected to multiple polymerase chain reactions to determine the GSTM1 and GSTT1 genotypes. RESULTS: There were no significant differences in the frequencies of the GSTM1 (P = .83, odds ratio 0.95) and GSTT1 (P = .24, odds ratio 0.75) null mutations between endometriosis patients and controls. The endometriosis group was divided into a subgroup of stage IV disease only, but no statistically significant differences were observed in the frequency of the GSTM1 null mutation (P = .88, odds ratio 0.96, 95% confidence interval 0.57-1.63) and the GSTT1 null mutation (P = .33, odds ratio 0.77, 95% confidence interval 0.45-1.30) between any of these groups and the controls. CONCLUSION: These findings suggest that the GSTM1 and GSTT1 null mutations are not likely to be associated with an increased risk of endometriosis in a Japanese population.

DNA Mutational Analysis↗

Polymorphism at codon 72 of the p53 gene is not associated with endometriosis in a Japanese population.

OBJECTIVE: Endometriosis is inherited as a complex trait, which means that multiple susceptibility genes interact with each other and the environment to produce the phenotype. Previous studies have implicated p53, a tumor suppressor gene, as a factor in the development of the disease. In a Japanese population, we investigated the frequency of the p53 polymorphism in women affected with endometriosis. METHODS: We compared the distribution of the p53 codon 72 polymorphism in endometriosis cases (n = 111) and population controls consisting of female neonates (n = 180) by using polymerase chain reaction restriction fragment-length polymorphism analysis in a Japanese population. RESULTS: The frequencies of the three p53 genotypes, Arginine (Arg)/Arg, Arg/Proline (Pro), and Pro/Pro in controls were 39.4%, 41.7%, and 18.9 %, respectively. The crude genotype frequencies in the endometriosis cases were similar to those of the controls (35.2%, 48.6%, and 16.2%, respectively). Using the Arg/Arg genotype as the reference, the odds ratios of the Arg/Pro and Pro/Pro genotypes were 1.30 (95% confidence interval [CI] 0.72-1.86, P =.33) and 0.96 (95% CI 0.47-1.94, P =.91), respectively. Thus, there were no significant differences in the frequency of the p53 codon 72 polymorphism between endometriosis cases and controls in this population. The endometriosis cases with severe disease only were also evaluated, but no significant difference was observed in the frequency of the polymorphism between this subgroup and the controls. CONCLUSION: Our findings suggest that the p53 codon 72 polymorphism is unlikely to be associated with endometriosis in Japanese women.

Codon↗

Neoadjuvant high-dose intraarterial infusion chemotherapy under percutaneous pelvic perfusion with extracorporeal chemofiltration in patients with stages IIIa-IVa cervical cancer.

OBJECTIVE: The objective of this study was to evaluate the response rate and survival of patients with locally advanced uterine cervical cancer who were treated with intraarterial infusion chemotherapy under percutaneous pelvic perfusion with extracorporeal chemofiltration (PPPEC). METHODS: Twenty-three untreated patients with stages IIIa-IVa cervical cancer were enrolled in the study. PPPEC was administered twice at 2 weeks interval using high-dose cisplatin alone (140-250 mg/m(2)) or high-dose cisplatin plus mitomycin C (7 mg/m(2)), pepleomycin (7 mg/m(2)) and 5-fluorouracil (700 mg/m(2)). Eighteen patients in whom the tumor downstaging was confirmed underwent radical surgery following PPPEC, whereas in the remaining five patients, radiotherapy was administered. RESULTS: Two weeks after the second PPPEC, the median volumetric tumor reduction and tumor response were 76% and 87%, respectively. Histologic response was 96%, while the tumor downstaging reached 83%. The curative surgery rate achieved was 89%. Five-year progression-free survival was 47% and 5-year survival rate was 74%. CONCLUSION: High-dose intraarterial infusion chemotherapy under PPPEC effectively achieved tumor downstaging and resulted in the favorable performance of the subsequent radical surgery and improved the 5-year survival rate of patients with locally advanced uterine cervical cancer.

Adult↗

The role of thyroid hormone in trophoblast function, early pregnancy maintenance, and fetal neurodevelopment.

OBJECTIVE: To review the literature on the roles of thyroid hormone in trophoblast function, early pregnancy maintenance, and fetal neurodevelopment. METHODS: MEDLINE was searched for English-language papers published from 1971 to 2003, using the key words "brain," "hypothyroidism," "placenta," "pregnancy," "threatened abortion," "thyroid hormone," "thyroid hormone receptor," "thyroid hormone replacement therapy," "thyroid hormone-responsive gene," and "trophoblast." RESULTS: Transplacental transfer of thyroid hormone occurs before the onset of fetal thyroid hormone secretion. Thyroid hormone receptors and iodothyronine deiodinases are present in the placenta and the fetal central nervous system early in pregnancy, and thyroid hormone plays a crucial role both in trophoblast function and fetal neurodevelopment. Maternal hypothyroxinemia is associated with a high rate of spontaneous abortion and long-term neuropsychological deficits in children born of hypothyroid mothers. Maternal iodine deficiency also causes a wide spectrum of neuropsychological disorders in children, ranging from subclinical deficits in cognitive motor and auditory functions to hypothyroid-induced cognitive impairment in infants. However, these conditions are preventable when iodine supplementation is initiated before the second trimester. Although thyroid hormone replacement therapy is effective for reducing the adverse effects complicated by maternal hypothyroidism, the appropriate dose of thyroid hormone is mandatory in protecting the early stage of pregnancy. CONCLUSIONS: Close monitoring of maternal thyroid hormone status and ensuring adequate maternal thyroid hormone levels in early pregnancy are of great importance to prevent miscarriage and neuropsychological deficits in infants.

Adult↗

3,5,3'-Triiodothyronine down-regulates Fas and Fas ligand expression and suppresses caspase-3 and poly (adenosine 5'-diphosphate-ribose) polymerase cleavage and apoptosis in early placental extravillous trophoblasts in vitro.

The present study was conducted to determine whether T(3) receptor exists in early placental extravillous trophoblasts (EVTs) and evaluate the influence of T(3) on Fas/Fas ligand expression, caspase-3, and poly (ADP-ribose) polymerase (PARP) cleavage and apoptosis in cultured early placental EVTs. EVTs with invasive phenotype, isolated from normal placental explants from early pregnancy through preincubation on human fibronectin-coated dishes and exhibited cytokeratin 7 and human placental lactogen immunopositive staining, were cultured in the absence or presence of T(3) (10(-7) to 10(-9) m). The presence of T(3) receptor in cultured EVTs was examined by immunocytochemistry, RT-PCR, and Southern blot analysis. Fas sensitivity was determined by treating the cells with an agonistic Fas antibody. Apoptosis was assessed by terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling, flow cytometry, and Hoechst nuclear staining. Fas and Fas ligand expression and caspase-3 and PARP cleavage were evaluated by immunocytochemistry. Early placental EVTs expressed a 212-bp c-erb Abeta1 transcript and the T(3) receptor protein and exhibited significant levels of apoptosis in culture. Treatment with T(3) reduced the expression of Fas and Fas ligand as well as cleavage of caspase-3 and PARP and suppressed apoptosis in cultured EVTs. Although addition of agonistic Fas antibody increased apoptosis in these cells, this response was markedly attenuated by the presence of T(3). These results demonstrate that T(3) receptor is present in early placental EVTs and that T(3) suppresses apoptosis by down-regulating the expression of Fas and Fas ligand. These findings are consistent with the hypothesis that T(3) promotes EVT invasion to the decidua by suppressing apoptosis in early pregnancy.

Apoptosis↗

Effects of 3,5,3'-triiodothyronine on the invasive potential and the expression of integrins and matrix metalloproteinases in cultured early placental extravillous trophoblasts.

It is well known that T(3) plays a crucial role in the maintenance of early pregnancy through the induction of endocrine function in villous trophoblasts. The effects of T(3) on extravillous trophoblast (EVT) function, however, remain to be elucidated. To investigate the possible role of T(3) in the regulation of EVT invasion to the decidua, we have examined whether T(3) affects EVT invasive potential and the expression of matrix metalloproteinase-2 (MMP-2), MMP-3, tissue inhibitor metalloproteinase-1, fetal fibronectin (FN), and integrin alpha(5)beta(1) in cultured early placental EVTs. Isolation and purification of trophoblasts differentiating into EVTs were performed by the enzymatic digestion of the anchoring chorionic villi, with the use of human FN-precoated culture dishes and FN-precoated Matrigel Transwells. The cells attached to the dishes were subcultured in DMEM supplemented with 10% fetal bovine serum for 48 h and were characterized by RT-PCR analysis after 24-h subculture and immunocytochemical analysis after 48-h subculture for specific EVT markers. Thereafter, the cultured cells were stepped down to a 4% fetal bovine serum condition and cultured in the presence or absence of T(3) (10(-8) m) for the subsequent 72 h. Matrigel invasion assay demonstrated that the treatment with T(3) significantly increased the number of cell projections of subsequent 24-, 48-, and 72-h cultured EVTs. RT-PCR analysis revealed that the treatment with T(3) increased the expression of MMP-2, MMP-3, fetal FN, and integrin alpha(5)beta(1) mRNA in subsequent 24-h cultured EVTs compared with those in control cultures. Immunocytochemical and Western immunoblot analyses revealed that treatment with T(3) increased the expression of MMP-2 and MMP-3 in subsequent 48-h cultured EVTs compared with those in control cultures. The present results suggest that T(3) (10(-8) m) may play a vital role in up-regulating the invasive potential of EVTs into the decidua.

Blotting, Western↗

Noncompaction of the left ventricular myocardium diagnosed in pregnant woman and neonate.

Noncompaction of the left ventricular myocardium (NCLV) is an uncommon congenital cardiomyopathy with poor prognosis. We describe a case of NCLV that developed in a pregnant woman and her neonate. A nulliparous woman was referred at 24 weeks' gestation due to dyspnea and fetal hydrops. Maternal echocardiography demonstrated NCLV with characteristic findings of prominent and excessive ventricular trabeculations and deep intertrabecular recesses in the left ventricle. An M-mode echocardiography suggested depressed left ventricular systolic function. A fetal echocardiography at 24 weeks' gestation demonstrated cardiomegaly, but morphologic findings were not definitive for NCLV. An emergency cesarean section was performed due to maternal heart failure. A neonatal echocardiography diagnosed NCLV with depressed left ventricular systolic function. The neonate died of cardiac failure on the second day of life. Autopsy confirmed the echocardiographic findings. Since patients with NCLV may develop heart failure, multidisciplinary management is mandatory. In addition, awareness of familial occurrence of NCLV should be kept in mind for early diagnosis in the fetus and neonate.

Adult↗

Changes in the expression and cytological localization of betacellulin and its receptors (ErbB-1 and ErbB-4) in the trophoblasts in human placenta over the course of pregnancy.

OBJECTIVE: Betacellulin (BTC), purified and cloned from mouse beta cell tumor (BTC-JC10), is regarded as a new member of the epidermal growth factor family. The present study was conducted to clarify the expression of BTC and its receptors, ErbB-1 and ErbB-4, in the trophoblasts in the human placenta over the course of pregnancy. DESIGN AND METHODS: Human placental tissues were obtained from 4 pregnant women at the 4th to 5th week of pregnancy (very early placentas), 10 women at the 6th to 12th week (early placentas), 5 women at the 18th to 21st week (mid placentas) and 8 women at the 38th and 40th week (term placentas). The mRNA expressions of BTC, erbB-1 and erbB-4 were evaluated by quantitative RT-PCR with Southern blotting and the expression of the soluble form of BTC was determined by western immunoblot with a specific antibody to BTC protein. Immunohistochemical staining of BTC, ErbB-1 and ErbB-4 was also performed. RESULTS: The levels of BTC mRNA expression in early and mid placentas were significantly higher than those in term placentas. The soluble form of BTC protein with an estimated molecular mass of 9.5 kDa was expressed in early and mid placentas, whereas the soluble form was not detected in term placentas. BTC from very early placentas until mid placentas was immunolocalized in syncytiotrophoblasts (S-cells), and was most abundant in early placentas. In contrast, BTC was immunolocalized in extravillous trophoblasts (EVTs), but not in villous trophoblasts in term placentas. The levels of erbB-1 mRNA in the early and mid placentas were significantly higher than those in term placentas, whereas the levels of erbB-4 mRNA in early placentas were significantly lower than those in mid and term placentas. ErbB-1 was immunolocalized in cytotrophoblasts in very early placentas, whereas it was immunolocalized in S-cells from early until term placentas. ErbB-4 from very early placentas until mid placentas was immunolocalized in S-cells, whereas ErbB-4 in the term placentas was detected in EVTs, but not in villous trophoblasts. CONCLUSIONS: These findings provide evidence for changes in expression and cytological localization of BTC and its receptors in the trophoblasts in human placenta over the course of pregnancy. BTC may play a pivotal role as a local growth factor in promoting the differentiated villous trophoblastic function via ErbB-1 in early placentas and in contributing to placental growth through the maintenance of EVT cell function via ErbB-4 in term placentas.

Betacellulin↗

Peritonitis caused by a ruptured, infected mesenteric cyst initially interpreted as an ovarian cyst. A case report.

BACKGROUND: Mesenteric cysts are rare intraabdominal lesions of childhood that may vary in presentation from an asymptomatic mass to an acute abdomen. CASE: We encountered a rare case of peritonitis caused by a ruptured, infected mesenteric cyst of the mesocolon in a female child that had been initially interpreted as a ruptured ovarian cyst. CONCLUSION: When confronted with a large unilocular or septated echolucent mass in the lower abdomen in female children, gynecologists should consider a mesenteric cyst in the differential diagnosis.

Child, Preschool↗

The role of human papilloma virus in the molecular biology of cervical carcinogenesis.

Research exploring the E6-p53 and E7-pRb model has resulted in the identity of the viral gene's actions on numerous cellular proteins and processes normally involved in cell growth and proliferation. Specially, several findings have established the various ways by which the HPV-infected cell may escape controls governing cell growth and proliferation, including the fidelity of the host cell's genome and apoptosis. A large body of knowledge already generated in this area supports the view that high-risk HPV types have the ability to transform cells into a malignant phenotype. Such ability, however, is not sufficient to actually and inevitably produce cervical carcinoma, as indicated by the frequent spontaneous clearance of HPV infection and the long delay between the onset of persistent infection and emergence of the malignancy. Delay in the participation of cofactors has been suggested as explanation in this regard. However, it remains unclear how and when cofactors or factors that are innate in the HPV-infected cells launch the host cells into an irreversible progression to carcinoma.

Apoptosis↗

Laminin-5 gamma2 chain and matrix metalloproteinase-2 expression in the neoplastic changes of uterine cervical squamous epithelium.

Laminin-5 is an essential component of epithelial basal membranes. Matrix metalloproteinase-2 (MMP-2) changes laminin-5 from static to migratory substrate by cleaving the short arm of the gamma2 subunit of the laminin-5. Recently, the expression of laminin-5 gamma2 chain has been reported to be a marker of invasiveness of epithelial malignant tumors. We investigated the expression of laminin-5 gamma2 chain and MMP-2 in the neoplastic changes of uterine cervical squamous epithelium. Tissue samples of normal uterine cervix, cervical intraepithelial neoplasia-1, -3 (CIN-1, -3) and squamous cell carcinoma keratinizing (SCC-K) and non-keratinizing (SCC-NK) were analyzed for expression of the laminin-5 gamma2 chain and MMP-2 by immunohistochemistry. In normal uterine cervix and CIN-1, laminin-5 gamma2 chain was immunolocalized only in the basal membrane. In CIN-3, expression of laminin-5 gamma2 chain and MMP-2 became apparent at the epithelial-stromal interface of epithelial cells. In SCC-K and SCC-NK, laminin-5 gamma2 chain and MMP-2 expression were abundant at the epithelial-stromal interface of tumor clusters. These results suggest that the expression of laminin-5 gamma2 chain and MMP-2 may be involved in the process of neoplastic changes of uterine cervical squamous epithelium.

Basement Membrane↗

Activation of the luteinizing hormone receptor in the extracellular domain.

Glycoprotein hormone receptors have ligand-binding ectodomains consisting of leucine-rich repeats, followed by a conserved cysteine-rich hinge region to the seven transmembrane (TM) region. Based on constitutively active mutations at Ser-281 in the hinge region of the thyroid-stimulating hormone receptor, we mutated the conserved serine in the luteinizing hormone (LH) receptor (S277I) and observed increased basal cAMP production and ligand affinity by mutant receptor. Conversion of Ser-277 to all natural amino acids led to varying degrees of receptor activation. Hydropathy index analysis indicated that substitution of neutral serine with selective nonpolar hydrophobic residues (Leu>Val>Met>Ile) confers constitutive receptor activation. Furthermore, mutation of the angular proline near Ser-273 to flexible Gly also led to receptor activation. The findings suggest the ectodomain of LH receptor constrains the TM region. Point mutations in the hinge region or ligand binding could cause conformational changes in the TM region that result in Gs activation.

Amino Acid Sequence↗

GnRH agonist action on granulosa cells at varying follicular stages.

In the present review, we attempt to summarize our recent research related to comparative effects of gonadotropin-releasing hormone (GnRH) agonist on the proliferation, apoptosis and differentiated function of cultured porcine granulosa cells from varying follicular stages. The inhibitory effect of GnRH agonist on Proliferating cell nuclear antigen positive rate of cultured cells was prominent in granulosa cells from small and medium but not from large follicles. By contrast, the inhibitory effect of GnRH agonist on 17beta-estradiol and progesterone secretion by cultured cells was prominent in granulosa cells from large but not from small and medium follicles. The stimulatory effect of GnRH agonist on apoptosis positive rate of cultured cells was, however, uniform regardless of the stages of follicular growth. These results demonstrate that GnRH agonist exerts diverse actions on granulosa cells over the course of follicular growth. One downregulates granulosa cell proliferation in immature follicles as well as steroidogenesis in mature follicles, and the other upregulates apoptosis of granulosa cells regardless of the stages of follicular growth.

Animals↗

Paradoxically abundant expression of Bcl-2 and adrenomedullin in invasive cervical squamous carcinoma.

BACKGROUND: The purpose of this study was to identify the role of Bcl-2 protein and adrenomedullin (AM) expression in relation to apoptosis in the neoplastic changes of squamous epithelium of the uterine cervix. METHODS: Apoptosis in sections of normal cervical epithelium, cervical intraepithelial neoplasia (CIN), and invasive squamous cell carcinoma was determined by terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick-end labeling (TUNEL) assay. Bcl-2 protein and AM expression were analyzed using the avidin-biotin immunoperoxidase method. RESULTS: On the basis of the TUNEL assay, the apoptosis positive rate of the nuclei in early invasive squamous carcinoma and in bulky invasive squamous carcinoma was significantly higher than that in normal cervical epithelium, but no such increase in the apoptosis-positive rate was noted in the nuclei in CIN. Immunohistochemical staining revealed that Bcl-2 protein and AM were immunolocalized in the cytoplasm of invasive squamous carcinoma cells, but not in either CIN lesions or normal cervical epithelium. Bcl-2 protein expression was more prominent in bulky invasive squamous carcinoma cells than in early invasive squamous carcinoma cells. AM expression was also more abundant in bulky invasive squamous carcinoma compared with that in early invasive squamous carcinoma. CONCLUSION: The present results suggest that the expression of Bcl-2 protein and AM in invasive squamous carcinoma may play crucial roles in selecting carcinoma cells resistant to apoptosis and in promoting malignant progression.

Adrenomedullin↗

Effects of progesterone on growth factor expression in human uterine leiomyoma.

It is now evident that the use of levonorgestrel-releasing intrauterine system (LNg-IUS) is effective for long-term management of menorrhagic women with uterine myomas because of a striking reduction in menorrhagia. This prompted us to characterize the effects of progesterone (P4) on the growth and apoptosis of uterine leiomyoma cells. On the other hand, we have recently noted that epidermal growth factor (EGF) and IGF-I play a crucial role in prompting uterine leiomyoma growth through stimulating the proliferative potential and inhibiting apoptosis of cultured human leiomyoma cells. In the present review, attention was paid to evaluate the effects of P4 on the expression of growth factors (EGF, IGF-I) and apoptosis-related factors (TNFalpha, Bcl-2 protein) in cultured uterine leiomyoma cells. Treatment with P4 augmented EGF and Bcl-2 protein expression, but inhibited IGF-I and TNFalpha expression in cultured leiomyoma cells. It is known that TNFalpha induces apoptosis in a variety of cell types and Bcl-2 protein is an apoptosis-inhibiting gene product. Thus, the results obtained suggest that P4 has dual actions on uterine leiomyoma growth: one is to stimulate leiomyoma cell growth and survival through up-regulating EGF and Bcl-2 protein expression as well as down-regulating TNFalpha expression in those cells, and the other is to inhibit leiomyoma cell growth through down-regulating IGF-I expression in those cells. This may explain why the size of uterine myomas during use of LNg-IUS increases in some but decreases in other instances. This may also explain why the size of uterine myomas during pregnancy does not increase despite the overwhelming increase in circulating concentrations of sex steroid hormones.

Apoptosis↗