Loss of expression of alpha4beta7 integrin and L-selectin is associated with high-grade progression of low-grade MALT lymphoma

Expression of adhesion molecule in low-grade B-cell mucosa-associated lymphoid tissue (MALT) lymphoma of the gastrointestinal tract has been reported in recent years, but these reports have primarily focused on low-grade gastrointestinal MALT lymphoma. In this study, we examined the lymphocytic homing receptor alpha4beta7 integrin, L-selectin, and VLA-4 and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) in low-grade lymphoma of the gastrointestinal tract and other organs such as the ocular adnexa and thyroid. We also observed changes in the expression pattern associated with high-grade transformation. Neoplastic cells in the gastrointestinal low-grade lymphoma and the low-grade component of high-grade MALT lymphoma were found to be alpha4beta7 integrin(+), L-selectin(+), whereas the gastrointestinal high-grade component and diffuse large B-cell lymphoma were found to be alpha4beta7 integrin(-), L-selectin(-). High endothelial venules in the gastric MALT lymphomas expressed MAdCAM-1. In the ocular adnexa low-grade MALT lymphoma, most cases were alpha4beta7 integrin(-), L-selectin(+); and in the thyroid, most cases of both low- and high-grade MALT lymphoma were alpha4beta7 integrin(-), L-selectin(-). These findings show that alpha4beta7 integrin and L-selectin may play an important role in the lymphocyte homing of gastrointestinal low-grade MALT lymphoma and in the loss of alpha4beta7 integrin expression throughout the course of high-grade progression.

Mifepristone regulates expression of apoptosis related genes Fas and FasL in mouse endometrium

AIM

To investigate the anti-implantation mechanism of mifepriston.

METHODS

In situ hybridization and immunohistochemistry were applied to determine mRNA and protein.

RESULTS

After mifepriston injection, the number of implantation sites were obviously reduced, mifepriston could inhibit the embryo implantation in mouse. The expression of apoptosis related genes, Fas and FasL, in mouse endometrium was also decreased after mifepriston treatment.

CONCLUSION

The expression of apoptosis related genes Fas and FasL is regulated by mifepriston and the inhibitory effect of mifepriston on the embryo implantation may be mediated by action on the Fas/FasL system.

Environmental change in Bashang region historical periods

The Bashang region is a typical vulnerable eco-environmental zone. Our analysis of paleodunes, paleosol profiles, and lake changes taking place during last ten thousands years indicated that: (1) 10-6.9 ka B.P. was a post-glacial temperature-increasing stage, in which lakes had their high water level; (2) 6.9-3.0 ka B. P. was a large warm stage, during which four paleosol layers were developed and climate fluctuation has assumed 4-5 small cold-humid and cold-dry alternations. Since 5.4 ka B.P., the lakes tended to gradually shrink; and by 2.1 ka B.P., water level has fallen by 2.7 m; (3) since 3.0 ka B. P. a general trend of the region was to change into a dry, warm-dry and cold-dry environment.

Expression of HSP70-2 gene during germ cell apoptosis in rat unilateral cryptorchid testes

To investigate the role of Hsp70-2 gene in germ cell apoptosis induced by heat stress, its expression changes were examined in rat normal and unilateral cryptorchid testes by using in situ hybridization, immunohistochemistry, and northern blot analysis techniques. The results showed that the expression level of Hsp70-2 gene declined slightly at the early stage of germ cell apoptosis, and dropped dramatically when most of the germ cells were undergoing apoptosis on day 7.5 after the induction of cryptorchidism. This report suggests for the first time that Hsp70-2 gene might not inhibit the apoptosis of germ cells at the early stage in cryptorchid testes. Hsp70-2 gene does not belong to the immediate early related genes that are responsible for germ cell apoptosis induced by heat stress.

[Source of plasminogen activator in rhesus monkey semen and its possible role in sperm capacitation]

Previous studies have demonstrated that plasminogen activator (PA) activity is significantly high in semen of infertile men, which is also high in semen when azoospermia or oligozoospermia is induced by injection of testosterone enanthate (TE) into healthy adult men or rhesus monkeys. To further clarify the source and possible role of PA in semen, the present study was undertaken to examine: (1) whether the mRNAs for tissue type PA (tPA), urokinase type PA (uPA), and PA inhibitor-1 (PAI-1) are expressed in epididymis, seminal vesicle and prostate gland of rhesus monkeys; and (2) whether PA has some effect on in vitro sperm capacitation as judged by the potential of sperm motility, acrosome reaction (AR) and in vitro fertilization. Our results showed that (1) mRNAs for PA and PAI-1 were expressed in epididymis, seminal vesicle and prostate gland, and (2) uPA, but not tPA, improved sperm mobility, induced AR and enhanced sperm capacity to fertilize mature eggs. Thus, it is concluded that PA activity in semen comes not only from testis and epididymis, but also from seminal vesicle and prostate gland; and that uPA, but not tPA, may play a role in sperm capacitation.

Plasminogen activators and inhibitors are transcribed during early macaque implantation

Plasminogen activators and inhibitors may be important early in primate implantation but evidence for this is sparse in non-human primates. We define the expression of urokinase type plasminogen activator (uPA), tissue-type plasminogen activator (tPA), plasminogen activator inhibitor type 1 (PAI-1) and type 2 (PAI-2), the receptor for uPA (uPAR) and fibrin/fibrinogen in monkey implantation sites. In situ hybridization and immuno-histochemical localization of rhesus monkey implantation sites (day 15-16 postovulation) indicate: (1) uPA mRNA is localized to placental trophoblast, epithelial plaque and endometrial stroma. (2) tPA mRNA is mainly expressed in glandular cells of endometrium. (3) PAI-1 expression is linked to a specific population of trophoblasts that confront maternal cells, adding support to our view that it has a regulatory role in trophoblast invasion. (4) Localization of tPA antigen confirms that uterine glands are the major source of tPA and that it is also closely associated with fibrin(ogen) suggesting its possible function during implantation is fibrinolysis. (5) Unlike uPA mRNA, however, the distribution of uPA protein and its cell surface receptor uPAR suggests that it mediates trophoblast invasion and plays a significant role in angiogenesis. (6) PAI-2, the inhibitor associated with pregnancy in humans, was found in unidentified cells located specifically along the maternofetal junction. This localization adjacent to areas of cell death at the maternofetal junction implies that it may have a role as a protective curtain with anti-apoptotic function. In conclusion our results suggest that gene expression of PAs and PAIs in early implantation sites are tissue-specific, location-sensitive and function-related.

[Germ cell apoptosis and regulation in testis]

Both spontaneous and induced germ cell apoptosis occur during the process of germ cell differentiation in testis, which is an important mechanism to remove surplus and abnormal germ cells. It has been known that germ cell apoptosis is under the control of endocrine, cell social association and gene. To elucidate the molecular mechanisms by which germ cell apoptosis is regulated and the elements of the death machinery will provide a basis for effective management of male infertility as well as more targeted approaches to male contraception.

New reference for the age at childhood onset of growth and secular trend in the timing of puberty in Swedish

The objectives of the present work were to present a new reference for the age at childhood onset of growth and to investigate the secular trend in the timing of puberty in a community-based normal population in Sweden. A total of 2,432 children with longitudinal length/height data from birth to adulthood were used to determine the two measures by visual inspection of the measured attained length/height and the change in growth velocity displayed on a computer-generated infancy-childhood-puberty (ICP) based growth chart. The series represents a sample of normal full-term children born around 1974 in Göteborg, Sweden. We found about 10% of children were delayed (>12 mo of age) in the childhood onset of growth based on the previous reported normal range, i.e. 14% in boys and 8% in girls. Distribution of the age at childhood onset of growth was skewed. The medians were 10 and 9 mo for boys and girls, respectively. After natural logarithmic transformation, the mean and standard deviation (SD) were 2.29 (anti-log 9.9 mo) and 0.226 for boys, 2.23 (anti-log 9.3 mo) and 0.220 for girls, respectively. The 95% normal ranges were 6.3-15.4 and 6.0-14.3 for boys and girls, respectively. The distribution of the timing of PHV was close to the normal distribution. The mean values were 13.5 y for boys and 11.6 y for girls with 1 y SD for both sexes.

CONCLUSION

A downward secular trend in the onset of puberty was clearly shown in the population. The age at childhood onset of growth did not correlate with the timing of puberty (r = -0.01 and 0.05, p > 0.7 and 0.1 in boys and girls, respectively). Normal ranges of the age at childhood onset of growth are in need of revise, as this study indicates. The new reference presented here could be a reliable indicator in further studies.

Anatomic basis of iliac crest flap pedicled on the iliolumbar artery

This paper presents the anatomy and clinical applications of an iliac crest flap pedicled on the iliolumbar artery. 54 iliolumbar arteries were filled with pink plastic in 27 adult cadavers. Their origin, course and branches, and the surroundings were investigated, and the external diameter, length of segments and terminal distribution were measured. The iliolumbar artery was constant, but with a few variations. Its length was 7.0 +/- 3.9 cm, and the outer diameter 2.0 +/- 0.4 mm at the lateral edge of the psoas major muscle. Based on the anatomic findings, the surgical technique for a bone flap based on the iliolumbar artery was designed. Its clinical applications included both free bone grafting (in 2 patients) and pedicled bone transfer (in another 2 patients). The clinical results were satisfactory. The iliac crest flap pedicled on the iliolumbar artery is a reliable bone flap for clinical usage.

Functionally inactive protein C inhibitor in seminal plasma may be associated with infertility

Protein C inhibitor (PCI) has been found in seminal plasma and is considered to protect intact surrounding cells and seminal plasma proteins from possible proteolytic damage. In the present study, we showed that although the antigenic levels of PCI in two seminal plasma samples from patients with infertility were normal or slightly elevated, their inhibitory activities toward urokinase plasminogen activator (uPA) and tissue-type plasminogen activator (tPA) were absent. In contrast, uPA and tPA proteolytic activities in these two samples were 20-60-fold higher than that from normal volunteers. A time-course analysis of PCI-uPA complex formation showed that >80% of the complex had been formed within 15 min in normal seminal plasma in the presence of heparin, compared with the total complex formed after 150 min incubation, whereas no response to heparin stimulation was observed in the assays with the two patient samples. Similarly, >90% of PCI-tPA complex was formed after 30 min of heparin stimulation in normal seminal plasma but no response was observed in the two patient samples. Kinetic assays of PCI inhibitory function in the presence of activated protein C (APC) showed that PCI inhibitory activity in the two patient samples was absent and not stimulated by heparin. Western blotting also showed that most of the intact PCI molecules, in normal samples, formed complexes with either uPA or tPA but there was no complex formed in one of the two patient samples and very little complex was observed in the other, suggesting that PCI in the two patient samples is inactive. These results suggest that the presence of functionally inactive PCI in seminal plasma may be associated with infertility.

Early linear growth retardation in Chongqing, China

OBJECTIVES

The objectives of this study were to investigate early linear growth retardation and to identify potential risk factors for it.

METHODOLOGY

A community-based prospective study was performed in Chongqing, China, with infants being examined at 12 and 15 months of age. A total of 101 infants were examined twice. Supine length, bodyweight, lower leg length, head circumference, middle upper arm circumference and biceps skinfold thickness were measured.

RESULTS

The prevalence of short stature (length-for-age standard deviation score, < -2) was 22% and 23% at 12 and 15 months of age, respectively, while the incidence of growth stunting (low growth velocity) between 12 and 15 months of age was 24%, using the stunting screening method. A mother having a history of abortion and infants having current episodes of diarrhoea were identified as risk factors for growth stunting.

CONCLUSIONS

We conclude that both short stature and growth stunting are common in the population studied. The stunting screening method used is applicable in developing communities.

Cloning of novel temperature-related expressed sequence tags in rat testis during spermatogenesis

Spermatogenesis needs the relatively cool environment of the scrotum in most mammals, it would be arrested when the testis was exposed to abdominal temperature. In this study, we have used a differential display PCR technique (DD-PCR) to screen temperature-related ESTs during spermatogenesis (TRS) in scrotal testes through a unilateral cryptorchid rat model after in situ analysis of testis cell DNA fragmentation. We reported here the cloning and sequencing of three such ESTs: TRS1, TRS3, and TRS4. Northern blot analysis confirmed that they were expressed specifically in scrotal testes. In situ hybridization showed that TRS1 was mainly expressed in the spermatocytes and the round spermatids in scrotal testis. Homology searches revealed that TRS1 and TRS3 were unknown cDNA sequences, and TRS4 was identical to a known EST whose function had not been reported. TRS1, TRS2, and TRS3 were first found to be temperature-related during spermatogenesis.

Regulation of the plasminogen activator system in the ovary

Extracellular matrix (ECM) not only provides a structural support for the organism, but also actively conducts cell-to-cell signal transduction and regulates cell proliferation, migration, development and metabolism. The targeted ECM degradation generated by plasminogen activator (PA) and regulated by plasminogen activator inhibitor (PAI) is, therefore, an event that affects a wide variety of physiological and pathological processes. The ovary is the best model to study the regulation and function of extracellular proteolysis mediated by multicomponents like the PA system. Studies carried out over the past 10 years in a number of laboratories have elucidated some of the biochemical events related to the function and regulation of the PA system in the ovary: hormone-induced proteolytic activity provided by tissue-type PA(tPA) and modulated by PAI-1 in the preovulatory follicles is responsible for a controlled and directed proteolysis leading to rupture of selected follicles during ovulation, whereas the coordinated expression of urokinase-type PA (uPA) and PAI-1 in the early growing follicle may be important in ECM degradation during cell proliferation and migration; the PA system may also play a role in the control of corpus luteum (CL) development through an autocrine or paracrine mechanism. Increase in tPA and PAI-1 expression in CL at a later stage is well correlated with a sharp decrease in CL progesterone production, while the increase in uPA mRNA levels and activity in the early stage of CL development is correlated with an increase in progesterone secretion.

Expression of tissue type and urokinase type plasminogen activators as well as plasminogen activator inhibitor type-1 and type-2 in human and rhesus monkey placenta

The distribution of mRNAs and antigens of tissue type (t) and urokinase type (u) plasminogen activators (PA) plus their corresponding inhibitors, type-1 (PAI-1) and type-2 (PAI-2) were studied in human and rhesus monkey placentae by in situ hybridisation and immunocytochemistry. Specific monkey cRNA and antibodies against human tPA, uPA, PAI-1 and PAI-2 were used as probes. The following results were obtained. (1) All the molecules tPA, uPA, PAI-1 and PAI-2 and their mRNAs were identified in the majority of the extravillous cytotrophoblast cells of the decidual layer between Rohr's and Nitabuch's striae and in cytotrophoblast cells of the chorionic plate, basal plate, intercotyledonary septae and cytotrophoblast cells of the chorionic villous tree. (2) Expression of uPA and PAI-2 was noted in villous trophoblast whereas tPA and PAI-1 were mainly concentrated where detachment from maternal tissue occurs. (3) No expression of tPA, uPA, PAI-1 and PAI-2 was observed in the basal plate endometrial stromal cells, chorionic plate connective tissue cells, septal endometrial stromal cells or villous core mesenchyme. (4) The distribution of probes observed following in situ hybridisation is generally consistent with the immunofluorescence pattern of the corresponding antigens and no significant interspecies differences were noted. It is possible that both decidual and extravillous trophoblast cells of placentae of human and rhesus monkey are capable of producing tPA, uPA, PAI-1 and PAI-2 to differing extents. Coordinated expression of these genes in the tissue may play an essential role in the maintenance of normal placentation and parturition. The differences in distribution we observed are consistent with the suggestion that coordinated expression of tPA and its inhibitor PAI-1 may play a key role in fibrinolytic activity in the early stages of placentation and separation of placenta from maternal tissue at term. On the other hand, uPA with its inhibitor PAI-2 appears mainly to play a role in degradation of trophoblast cell-associated extracellular matrix, and thus may be of greatest importance during early stages of placentation.

Expression of the steroidogenic acute regulatory protein and luteinizing hormone receptor and their regulation by tumor necrosis factor alpha in rat corpora lutea

Expression of both mRNA and protein of the steroidogenic acute regulatory protein (StAR), in correlation with progesterone (P) production and LH receptor (LHR) mRNA expression, was studied in the corpora lutea (CL) of gonadotropin-induced-pseudopregnant and pregnant rats at various stages of CL development. Immature female rats, 21-22 days old, were injected s.c. with 20 IU eCG to stimulate follicle growth and then with 20 IU hCG 48 h later to induce ovulation. The ovaries were removed at various stages of CL development; either CL were isolated and snap frozen for total RNA analysis, or whole ovaries were fixed in Bouin's fluid for paraffin sectioning. The results of in situ hybridization, immunohistochemistry, and Northern blotting showed that the increase in StAR mRNA and protein expression was well correlated with the increase in serum P concentration. StAR expression was restricted to the luteal cells or theca cells in antral follicles. Both StAR mRNA and protein in the CL of pseudopregnant rats increased steadily on Day 1 and Day 4, reached highest levels on Day 4, and then dropped sharply on Day 8 when luteolysis takes place. LHR mRNA content was high on Day 1 but dropped significantly on Day 2. LHR mRNA increased to high levels on Day 4 and 8 and then declined on Day 12. StAR mRNA and protein levels in the CL of pregnant rats were high during early luteal development (Day 2, 4), increased even further on Day 9, and decreased on Day 13 when luteolysis takes place. It is therefore suggested that the expression of StAR coincides well with the capacity of P production in the CL and that StAR expression can be used as a functional "marker" of CL development. To study the possible effect of cytokines on StAR expression, pseudopregnant rats on Day 5 were injected s.c. with 10 IU hCG plus 20 microg prolactin (PRL), with or without 500 IU tumor necrosis factor alpha (TNFalpha) 30 min later. TNFalpha significantly inhibited hCG/PRL-induced StAR and LHR mRNA expression at 1 and 3 h post-TNFalpha. It is suggested that the luteolytic effect of TNFalpha may be mediated by its direct inhibition on StAR expression or by an indirect decrease in LHR expression.

[Localization and expression of TR3 orphan receptor in mouse testis]

By means of in situ hybridization and immunohistochemistry, the expression and cellular localization of orphan receptor TR3 and its mRNA were observed. The results showed that both TR3 and its mRNA were expressed in a significant amount in mouse testis, and the expression level of TR3 mRNA was different in different seminiferous tubules. TR3 mRNA was specifically expressed in germ cells, mainly in spermatogonia and less advanced primary spermatocytes, whereas TR3 receptor protein was mainly localized in germ cells. It is suggested that TR3 may play an important role in regulating the early stage of germ cell development in mice.

Induction of an intronic enhancer of the human ciliary neurotrophic factor receptor (CNTFRalpha) gene by the TR3 orphan receptor

A hormone response element, CNTFRalpha-NBRE (5'-AAAGGTCA-3') has been identified in the fifth intron of the alpha component of ciliary neurotrophic factor receptor gene (CNTFR-15) for the human TR3 orphan receptor (TR3). A specific binding between in vitro expressed TR3 and CNTFRalpha-NBRE was demonstrated by using electrophoretic mobility shift assay. A reporter gene assay using chloramphenicol acetyl-transferase (CAT) showed that CNTFR-15 has an enhancer activity that could be induced by TR3 in a dose-dependent manner. This induction was significantly reduced in the absence of CNTFRalpha-NBRE. Together, these results indicate CNTFRalpha-NBRE is sufficient to mediate TR3 action in inducing the enhancer activity of CNTFR-15. Our finding may, therefore, suggest CNTFRalpha is a target gene regulated by TR3 and expand the role of TR3 in the nervous system.

Prolactin regulation of tissue type plasminogen activator and plasminogen activator inhibitor type-I gene expression in eCG-primed rat granulosa cells in culture

The present study was designed to investigate the effect of prolactin (PRL) on plasminogen activator inhibitor-I (PAI-I) and tissue type plasminogen activator (tPA) gene expression in eCG-primed granulosa cells in vitro. At 46 h after the hormone treatment, ovaries were removed, and granulosa cells were prepared for culture. Cells were incubated for various times in serum-free medium in the presence or absence of LH and PRL alone or in combination. tPA and PAI-I activities in the media were assayed by fibrin overlay and reverse fibrin autograph, respectively. Cytoplasmic RNA from granulosa cells was prepared using the NP-40 method and was assayed for PAI-I and tPA mRNA levels. We demonstrated the following. 1) PRL increased PAI-I mRNA production in cultured granulosa cells. Inclusion of LH with PRL had a synergistic effect on increasing PAI-I mRNA levels. After 48-h culture, 3-fold increases in PAI-I mRNA levels were seen with LH in combination with PRL as compared with PRL alone. The synergistic increase in PAI-I mRNA levels occurred in a dose- and time-dependent manner. 2) The increase in PAI-I mRNA synthesis by PRL alone, or by PRL in combination with LH, was well correlated with the changes in PAI-I activity and antigen levels in the conditioned media. 3) PRL in the culture also dramatically decreased LH-induced tPA mRNA and activity in a dose- and time-dependent fashion. The decrease in the tPA activity by PRL was also correlated with an increase in the amount of PA-PAI-I complexes in the cell-conditioned media. 4) In situ hybridization of tPA and PAI-I mRNAs in the cultured granulosa cells also showed that PRL was capable of enhancing PAI-I mRNA while diminishing tPA mRNA production induced by LH. This suggests that the dose- and time-dependent decrease in the gonadotropin-induced tPA activity in the culture by the presence of PRL may be due to decreasing tPA mRNA synthesis on one hand and to neutralization of the tPA activity by the increased PAI-I activity on the other.

[An animal experiment and clinical investigation on the protective effect of selenium on the microcirculation induced by free radical damaged RBCs]

Fluorescent labeling image analysis was used to evaluate the changes in cerebral arteriole and veinlet diameters (D), circulation velocities (FV) and permeability (VP) in rats; while in clinics, a laser-doppler device was used for assessing changes of skins and muscles microcirculation. The results show that in control rats, equal volume perfusion of free radical damaged RBCs resulted in decreases of D and FV significantly but VP was increased, whereas in the case when free radical damaged RBCs were perfused together with selenium, no disturbances in the D and VP were observed with FV even improved. In the human control group, either average skin microcirculative perfusions (ASMP) at 25 degrees C or maximal skin microcirculative perfusions (MSMP) at 42 degrees C were evidently decreased during myocardial ischemia/reperfusion period, while ASMP at 24th hour of post-surgery was kept reducing. At the same time, the changes in muscles microcirculative perfusions (MMP) tended to be similar to the skin, but overloaded than the pre-surgery levels at 24th hour of post-surgery period. In the selenium group before surgery, the ratio of MSMP to ASMP was obviously increased than the control group (3.95 in Se group vs 1.74 in control group, P < 0.05), but did not have significantly differences in ASMP, MSMP and MMP between the two groups during surgery period. RBC deformabilities were not changed. At 24th hour post-surgery, the ASMP were almost restored to pre-surgery levels. However, MMP were still lower than the pre-surgery levels.

CONCLUSIONS

(1) free radical damaged RBC perfusion leads to damage of microcirculation; (2) selenium is highly efficient in protecting microcirculation from free radical damaged RBC disturbance; and (3) Oral administration of selenium may improve pre-surgery maximal skin microcirculative perfusion and promote recovery of the worsened skin microcirculation in addition to prevent the occurrence of RBC deformability.

Risk factors for impaired length growth in early life viewed in terms of the infancy-childhood-puberty (ICP) growth model

A difference in length or height growth is observed between populations in developing and developed countries and, within a country, between well-off and poor subpopulations. The aim of this community-based study was to identify possible risk factors for growth stunting in early life using the infancy-childhood-puberty (ICP) growth model. A periurban slum, a village and an urban slum, plus a local control group in Lahore, Pakistan, were investigated. In total, there were 425 infants born from September 1984 to March 1987 in the study. Children were followed from birth to 24 months and anthropometric data were recorded at each examination. A well-designed questionnaire was used to collect background information to identify risk factors for growth faltering over this period. The age at onset of the childhood component was determined individually using the ICP growth model. A late onset was defined as onset after 12 months. Univariate odds ratio analysis identified 20 significant risk factors for a delayed childhood onset in the total sample. Backward logistical analysis showed that only six variables were significant, i.e. small number of rooms in a household, episode(s) of diarrhoeal diseases, poor house structure, low body mass index, early end of breastfeeding and birth in warm season. Stratified analysis showed that episode(s) of diarrhoeal diseases and birth in warm season were the only significant risk factors in the two poor areas. This study also found that the impact of diarrhoeal diseases on length growth persisted after allowing for birth season. Seasonal variation in length growth was seen in the age at onset of the childhood component. General socioeconomic status was found to be a risk factor for growth faltering in early life. Diarrhoeal diseases and being born in a warm season are particular risk factors for growth faltering in early life.

Growth stunting in early life in relation to the onset of the childhood component of growth

AIMS

Growth stunting is prevalent in developing countries. The prevalence of stunting ranges from 10-80% or more. The critical period for growth faltering in length is between six and 18 months. The aims of this study were 1) to investigate the association between the age at onset of the childhood component and growth stunting in early life; 2) to develop a screening method for identifying any individual infant subject to stunting in early life.

MATERIALS & METHODS

This community-based longitudinal study was carried out in Lahore, Pakistan. Three studied areas and one local control group were included in the study. There were 425 subjects for whom data were available for determining the age at onset of the childhood component. The onset was defined as an abrupt increase in length velocity. It was determined individually using the infancy-childhood-puberty growth model.

RESULTS

The medians of the age at onset of childhood component were 15, 13, 10 and 9 months in the periurban, village, urban and control groups, respectively. The onset was significantly related to both length and length velocity during the critical period of stunting. Based on the distribution of individual length increment from 12 to 15 months, 2.0 and 3.0 cm were chosen as the cut-off points to identify a stunting infant. In the normal onset group, 84% of the children were identified as growing normally; in the delayed onset group, 61% were identified as stunting. Using this screening method, 97% of children have a delayed onset if their length increase is below 2 cm from 12 to 15 months; 99% of them have a normal onset if the increase is above 3 cm over the same period.

CONCLUSIONS

The age at onset of the childhood component can significantly explain the variations in both length and length velocity in early life. The stunting screening method reported here is simple. It can be used in almost any situation, such as a pediatric clinic or community-based survey.

Localization and distribution of tissue type and urokinase type plasminogen activators and their inhibitors Type 1 and 2 in human and rhesus monkey fetal membranes

Fetal membranes consist of 10 distinct layers including components of amnion, chorion and decidua, the latter being of maternal origin. They form mechanically integrated sheets capable of retaining amniotic fluid and play an essential role in protecting fetal growth and development in the pregnant uterus. The extracellular matrix, substrate for plasminogen activators (PAs), is an important supportive framework of the fetal membranes. Fetal membranes from women with preterm premature rupture of membranes may differ in their protease activity compared with normal membranes. To identify the presence of PAs and their inhibitors (PAI) and their possible role in the process of fetal membrane rupture, this study investigated the distribution and localization of both protein and mRNA for tissue (t) and urokinase (u) PA and their inhibitors type 1 (PAI-1) and type 2 (PAI-2) in amniochorion of human and rhesus monkey using conventional and confocal immunofluorescence microscopy. In situ hybridization analysis showed that the distribution and localization of mRNAs for tPA, uPA, PAI-1 and PAI-2 were similar in the fetal membranes of human and rhesus monkey; no obvious species difference was observed. Evidence of tPA mRNA was detected in amniotic epithelium, trophoblast cells and nearly all cells of the decidual layer. Strong expression of uPA mRNA was noted in the decidual cells which increased in intensity as the abscission point was approached. Weak staining in chorion laeve trophoblast was also detected. In situ hybridization experiments showed PAI-1 mRNA to be concentrated mainly in the decidual cells, some of which were interposed into the maternal-facing edge of the chorion laeve. Maximal labelling of the decidua occurred towards the zone of abscission. Weak expression of PAI-1 mRNA was also noted in some cells of the chorion laeve. The distribution of PAI-2 mRNA in amniochorion was also concentrated in the cells of the decidual layer, maximum expression of the mRNA was in the level of abscission. No detectable amount of mRNAs for tPA, uPA, PAI-1 and PAI-2 was found in the fibroblast, reticular and spongy layers. Distribution of the proteins of tPA, uPA and PAI-1 in the fetal membranes of these two species was consistent with the distribution of their mRNA. Anti-PAI-2 immunofluorescence was found to be strongly concentrated in the amniotic epithelium, but PAI-2 mRNA was negative in this layer, suggesting that the epithelium-associated PAI-2 is not of epithelial origin. These findings suggest that a local fibrinolysis in fetal membranes generated by precisely balanced expression of PAs and their inhibitors via paracrine or autocrine mechanisms may play an essential role in fetal membrane development, maturation and in membrane rupture. Following an analysis of the distribution and synthesis of activators and inhibitors it was found that they may play a role in abscission during the third stage of labour.

[Effects of stimulation at different areas of nucleus raphe dorsalis on genioglossus and diaphragm activities]

Effects of electrical and chemical stimulation of the dorsal and ventral areas of the nucleus raphe dorsalis (dNRD and vNRD) on genioglossus and diaphragm activities were observed in 48 urethane-anaesthetized and vagotomized rabbits. (1) Long train electrical stimulation at the dNRD facilitated genioglossus and diaphragm activities. (2) Long train electrical stimulation delivered to the vNRD excited genioglossus activity but inhibited diaphragm activity. (3) Effects of microinjection of glutamate at the dNRD and vNRD were similar to the effects of electrical stimulation. The above results suggest that excitation of nucleus raphe dorsalis (NRD) increases genioglossus activity and reduces upper airway resistance. The dNRD and vNRD play different roles in modulating diaphragm activity.

Prolactin inhibition of FSH-induced tissue type plasminogen activator expression in cultured rat granulosa cells

This study was designed to investigate whether prolactin (PRL) affects coordinated regulation of tissue plasminogen activator (tPA) and plasminogen activator inhibitor type-I(PAI-I) gene expression in rat granulosa cells in vitro. Several methods, such as SDS-PAGE, immunoblot etc. were used to detect the effect of PRL on tPA and PAI-I gene expression. The results demonstrated: (1) PRL increases PAI-I mRNA production in cultured granulosa cells. Inclusion of follicle stimulating hormone (FSH) with PRL has a synergistic effect on the increase of PAI-I mRNA levels. After 48 h culture in the presence of FSH with PRL, a 7.8-fold increase in PAI-I mRNA levels is observed as compared with PRL alone. The synergistic increase in PAI-I mRNA levels occurs in a dose- and time-dependent manner; (2) the increase in PAI-I mRNA synthesis in the cells by PRL alone, or PRL in combination with FSH, is well correlated with the changes of PAI-I activity levels in the conditioned media; (3) PRL in culture also decreases FSH-induced tPA activity level in a dose-dependent fashion. The decrease in FSH-induced tPA activity level by PRL is correlated with an increase in the amount of PA-PAI-I complexes in the conditioned media. This suggests that the decline of tPA activity is related to neutralization of tPA by the increased PAI-I activity in the media.

Prolactin delays gonadotrophin-induced ovulation and down-regulates expression of plasminogen-activator system in ovary

This study was conducted to determine whether prolactin (PRL) suppresses gonadotrophin-induced ovulation and disturbs the co-ordinated gene expression of tissue type plasminogen activator (tPA) and plasminogen activator inhibitor type-1 (PAI-1) in rat ovary. Immature female rats were injected with 10 IU pregnant mare's serum gonadotrophin to stimulate follicle growth, and 48 h received different doses of prolactin followed by 7 IU human chorionic gonadotrophin (HCG). The oviducts were examined for the presence of ova, and the amounts of tPA and PAI-1 mRNA present in the ovary were measured at various times after the hormone treatment. PRL had no significant effect on ovarian weight but caused a dose-dependent decrease in ovulation number. In the control animals receiving HCG alone, 13.3 +/- 1.3 (mean +/- SEM) ova/oviduct were found; while in animals receiving HCG plus 50, 100 or 200 microg PRL, the ovulation number was dose-dependently suppressed by 53.6, 66.9 and 76% respectively at 18 h after treatment. PRL suppression of HCG-induced ovulation was time-dependent. By 24 h after treatment, the number of ova in the oviducts in HCG- and HCG plus PRL-treated groups was not significantly different. PRL also suppressed HCG-induced tPA gene expression in a dose- and time-dependent manner. At all time points examined, tPA mRNA content of whole ovaries and granulosa cells (GC) in PRL-treated groups was lower than in the HCG-treated controls. The activities of PAI-1 in ovarian extracellular fluid (OEF) and PAI-1 mRNA in the theca-interstitial cells (TI) in the PRL-treated groups were higher than in the HCG-treated controls. The highest stimulation by PRL of PAI-1 activity in OEF and of PAI-1 mRNA in TI was observed at 9 h and 6 h after HCG treatment respectively. The localization of tPA and PAI-1 antigens in the ovaries was consistent with changes in the mRNA and activity levels. These data suggest that PRL temporarily delays, but does not completely inhibit, HCG-induced ovulation, which may be caused by a suppression of PA-mediated proteolysis.