17β-estradiol and progesterone regulate multiple progestin signaling molecules in the anteroventral periventricular nucleus, ventromedial nucleus and sexually dimorphic nucleus of the preoptic area in female rats

Recent work identified novel progestin signaling molecules, including progesterone receptor membrane component 1 (Pgrmc1), Pgrmc2, serpine mRNA binding protein 1 (Serbp1), progestin and adiponectin receptors 7 (Paqr7) and Paqr8. These molecules mediate rapid progesterone (P(4)) effects in non-neural tissue and we recently mapped their expression in the brain. Many rapid effects of P(4) require 17β-estradiol (E(2)) and P(4) priming; therefore, we examined the effects of ovarian hormones on the expression of these non-classical progestin signaling molecules. We focused specifically on the anteroventral periventricular nucleus (AVPV), the sexually dimorphic nucleus of the preoptic area (SDN-POA) and the ventrolateral portion of the ventromedial nucleus (VMNvl). These brain nuclei are important for female reproduction. Ovariectomized adult female rats were implanted with capsules containing sesame oil or E(2), and injected 48 h later with sesame oil or P(4). Brains were collected 8 h later and RNA was isolated from the AVPV, SDN-POA and VMNvl. We assessed the effects of ovarian hormones on mRNA levels using quantitative polymerase chain reaction (QPCR). In the AVPV, Serbp1 mRNA levels were increased by P(4) in the presence of E(2), and Paqr8 was downregulated by P(4) alone. In the SDN-POA, combined E(2) and P(4) increased Pgrmc1 and Serbp1 mRNA levels, and E(2) alone increased Paqr8 mRNA levels. Finally, in the VMNvl, P(4) increased mRNA levels encoding Pgrmc1, Pgrmc2 and Serbp1, and the combination of E(2) and P(4) increased Pgrmc1 and Serbp1 mRNA levels. Paqr7 was not regulated by E(2) or P(4) in any brain region examined. In summary, we showed that ovarian hormones regulate novel progestin signaling molecules in brain regions important for the neuroendocrine control of reproduction.

The genetic variation of the human HMGB1 gene

High-mobility group box 1 protein (HMGB1) is a nuclear DNA-binding protein, which also functions as a pleiotropic cytokine, implicated in the pathology of several different immune-mediated diseases. The purpose of this study was to examine the HMGB1 gene for putative polymorphisms in 103 healthy Caucasian Danish blood donors. A total of six polymorphisms and four mutations were identified in the HMGB1 gene. Subsequent MatInspector estimation revealed that several polymorphisms might have a potential regulatory impact on HMGB1 transcription. This study has characterized genetic variations in the HMGB1 gene locus, which may have a regulating role in the expression of HMGB1, providing the basis for molecular investigations of the HMGB1 gene in different disease settings.

Alloreactivity as therapeutic principle in the treatment of hematologic malignancies. Studies of clinical and immunologic aspects of allogeneic hematopoietic cell transplantation with nonmyeloablative conditioning

Allogeneic hematopoietic cell transplantation (HCT) represents a potentially curative treatment modality in a range of hematologic malignancies. High-dose myeloablative radio-chemotherapy has conventionally been used as part of the preparative regimen before HCT for two reasons: it has a profound immunosuppressive effect on the host, limiting the ability to reject the graft and it has substantial anti-tumor efficacy. Graft rejection is an example of alloreactivity as alloreactivity denotes the immunologic reactions that occur when tissues are transplanted between two individuals within the same species. If the immune system of the host is suppressed to a degree where rejection does not occur, the possibility arises that immunocompetent donor cells can attack the recipient tissues. This phenomenon is termed Graft-versus-Host disease (GVHD) if healthy tissues of the host are attacked and the Graft-versus-Tumor (GVT) effect if the malignant cells are the targets of the reaction. Clinical studies have shown that patients who develop GVHD have a lower risk of relapse of the malignant disease and that donor lymphocyte infusion can induce durable remissions in patients with relapsed disease following the transplant. These observations indicate that a GVT effect can be present following allogeneic HCT and that this effect, like GVHD, is an alloreactive response. The toxicity of HCT with myeloablative conditioning is considerable and this limits the use of this procedure to patients below 50-60 years of age. A large proportion of the patients with hematologic malignancies are older than 60 years at diagnosis and they are therefore not eligible for this treatment. During the last decade, conditioning regimens that are nonmyeloablative or have reduced intensity have been developed. The purpose of this development has been to extend the use of allogeneic HCT to older patients and to patients who due to the malignant disease or to comorbidities are unable to tolerate myeloablative conditioning. In allogeneic HCT with nonmyeloablative conditioning the curative potential relies entirely on the ability of the donor cells to elicit a GVT effect. Allogeneic HCT with nonmyeloablative conditioning was introduced at Department of Hematology at Rigshospitalet in March 2000. The results of this treatment modality have been promising and we and others have shown that durable remissions can be obtained in patients who are heavily pretreated. One of the goals of allogeneic HCT with nonmyeloablative conditioning was to perform both the actual transplant procedure and the clinical follow up in the outpatient setting. In the first 30 patients transplanted at Rigshospitalet, we observed that the transplant itself and the first weeks post transplant could be performed as an outpatient procedure in a number of patients. However, all the patients were admitted and the median duration of hospitalization was 44 days during the first year post transplant. Complications such as infections and GVHD were common causes of hospitalization and studies from other centers have shown that infections, GVHD and relapse of the malignancy are the major obstacles to a good result of allogeneic HCT with nonmyeloablative conditioning. One way to improve the results of this treatment would therefore be to reduce the incidence of GVHD without compromising the GVT effect. In HCT with nonmyeloablative conditioning the relatively well-defined antineoplastic effect of high-dose myeloablative radio-chemotherapy is substituted with the alloreactive effect of the donor cells. Because the level of alloreactivity varies widely between different donor-recipient pairs, the ability to monitor the level of alloreactivity following the transplant would therefore be desirable. To this end we have investigated the ability of different immunologic and molecular methods to quantify the level of ongoing alloreactivity following the transplant. By simultaneous determination of the fraction of T cells of donor origin (donor T-cell chimerism) and the total number of T cells in the peripheral blood, we observed that patients with a high number of donor CD8 + T cells on day +14 had a high risk of acute GVHD. Other studies have shown that the level of donor T-cell chimerism early after transplant predicts the development of acute GVHD. One way to exploit this knowledge could be to individualize the pharmacologic immunosuppression given post transplant. This immunosuppression is given primarily to prevent the development of GVHD but may also inhibit the GVT effect. In patients with a low risk of GVHD early tapering of the immunosuppression could be done, while the period of immunosuppression could be extended in patients with a high risk of GVHD. In this way the GVT effect could theoretically be optimized in each patient and the results of the treatment improved. In another study we used limiting dilution analysis to monitor the frequencies of interleukin (IL)-2 producing helper T cells responding to recipient or donor antigens following the transplant. The conclusion from this study was that both the technical performance and the data analysis were to complex for this method to be used as a routine clinical tool. However, the study showed that immune responses following HCT are subject to a tight regulation and suggested that this regulation could be due to regulatory cell populations. Such regulatory cell populations have been used successfully in animal models to treat acute GVHD. The secretion of cytokines is an important aspect of immune responses. We analyzed cytokine gene expression in mononuclear cells obtained from patients and donors before and after HCT. Patients with acute GVHD had lower levels of IL-10 mRNA on day +14 than patients who did not develop acute GVHD. Patients who experienced progression or relapse of the malignant disease were characterized by higher levels of IL-10 mRNA before the transplant than patients who remained in remission. The conclusion of this study was that IL-10 might be an inhibitor of alloreactivity following allogeneic HCT with nonmyeloablative conditioning. Allogeneic HCT with nonmyeloablative conditioning represents a major step forward in the treatment of patients with hematologic malignancies. However, many issues such as whom to transplant and when the transplant should be performed remain to be clarified. Large prospective studies, involving collaboration between centers, are needed to define the role of HCT with nonmyeloablative conditioning along with other treatment modalities. In addition, it is important to continue to elucidate the immunologic mechanisms that are responsible for GVHD and the GVT effect.

Evidence for involvement of clonally expanded CD8+ T cells in anticancer immune responses in CLL patients following nonmyeloablative conditioning and hematopoietic cell transplantation

We have analyzed the clonotype composition of CD8+ T cells following nonmyeloablative (NMA) conditioning and hematopoietic cell transplantation (HCT), of patients with chronic lymphocytic leukemia (CLL). Consecutive analyses of blood samples taken up to 2 years following HCT, demonstrated that CD8+ T-cell clonality was highly dynamic in the early phases after HCT, but became more stable after 4-5 months. Moreover, donor lymphocyte infusion (DLI) given for disease progression in one of the patients led to establishment of recurrent as well as new T-cell clonotypes. This coincided with disease remission, strongly suggesting that these T cells were engaged with anti-CLL cytotoxicity. To examine the functional capacity of stable clonally expanded T cells after HCT, CD8+ T cells isolated post-transplant from the recipients were stimulated ex vivo with CLL cells and subsequently analyzed by FACS for surface expression of the marker for cytotoxic activity, CD107a. Stimulation with CLL cells indeed led to surface expression of CD107a, and clonotype analyses of sorted cells demonstrated that CD107a positive T cells were stably expanded following HCT. Our data suggest that clonally expanded CD8+ T-cell clones participate in the ongoing T-cell response against CLL cells following HCT with NMA conditioning.

Sex-related differences in the distribution of opioid receptor-like 1 receptor mRNA and colocalization with estrogen receptor mRNA in neurons of the spinal trigeminal nucleus caudalis in the rat

We recently reported that exogenously applied orphanin FQ, the endogenous ligand for opioid receptor-like 1 (ORL(1)) receptor, produces sex-specific modulation of trigeminal nociception, and that estrogen contributes to these sex-related differences. Estrogen could produce these sex-related differences by altering the expression of the ORL(1)-receptor gene in the trigeminal nucleus caudalis. Utilizing in situ hybridization, we compared levels of ORL(1) receptor mRNA and investigated its colocalization with estrogen receptor mRNA in trigeminal neurons. Our results showed that in male rats, ORL(1) receptor mRNA is abundantly expressed in the rostral part of the trigeminal nucleus caudalis, and at the junction of caudalis and interpolaris (Vc/Vi). In comparison with males, levels of ORL(1) receptor mRNA were not significantly different in proestrus females, but were significantly higher in the rostral trigeminal nucleus caudalis and at the junction of Vc/Vi of diestrus females. In addition, ovariectomy raised the levels in the rostral trigeminal nucleus caudalis, and at the junction of Vc/Vi. Levels were reduced to proestrus levels in these regions following estradiol replacement. Our results also showed that ORL(1) receptor mRNA is present in majority of estrogen receptor (alpha and/or beta) mRNA-containing neurons. We conclude that there are sex-related differences in the ORL(1)-receptor gene expression in the trigeminal nucleus caudalis, which appear to be determined in part by estrogen levels.

A comparison of T-, B- and NK-cell reconstitution following conventional or nonmyeloablative conditioning and transplantation with bone marrow or peripheral blood stem cells from human leucocyte antigen identical sibling donors

This retrospective study compares the reconstitution of T, B and NK cells in three groups of patients transplanted for haematological malignancies with grafts from their HLA-identical sibling donors. In all, 15 patients received PBSC after a nonmyeloablative conditioning regimen consisting of fludarabine and 200 cGy TBI, 13 patients received PBSC after myeloablative conditioning and 37 patients received BM after myeloablative conditioning. In the nonmyeloablative group, the NK cells normalised after 1 month, the CD8+ T cells normalised after 3 months, the CD4+ T cells reached near normal values after 9 months and the B cell values were reduced until 12 months after transplant. In the two myeloablative groups, recipients of PBSC had a significantly higher number of CD4+ T cells after 4 months (P=0.004) and after 12 months (P=0.001), than recipients of BM. We found no differences in the T cell reconstitution between the two PBSC groups. This was of interest as the recipients of nonmyeloablative conditioning were older (P<0.001) and had a higher occurrence of chronic GVHD (P<0.05) than the recipients of myeloablative conditioning. In contrast, the recipients of nonmyeloablative conditioning had a delayed B cell recovery when compared to the patients who received myeloablative conditioning (P=0.04).

Oestradiol-dependent and -independent modulation of tyrosine hydroxylase mRNA levels in subpopulations of A1 and A2 neurones with oestrogen receptor (ER)alpha and ER beta gene expression

Oestradiol (E2) induces luteinizing hormone-releasing hormone (LHRH) hypersecretion, thereby triggering LH surge release in ovariectomized (OVX) rats. Neural signals responsible for the surge are marked by a morning increase in LHRH gene expression and an afternoon increase in LHRH release. Evidence suggests that subpopulations of noradrenergic neurones may be responsible for one or both of these signals. To further investigate this issue, we examined effects of E2 on the activity of A1 and A2 noradrenergic neurones, as reflected in changes in tyrosine hydroxylase (TH) mRNA expression, on the day of LH surge release. We then used dual-label in situ hybridization to determine whether E2-induced changes occurred primarily in A1 and A2 subdivisions wherein most noradrenergic neurones expressed oestrogen receptor (ER)alpha and/or ER beta mRNA. We found that in all subdivisions, levels of TH mRNA were higher in E2- than oil-treated rats at 12.00 h. These differences resulted from a decline in TH mRNA expression in oil-treated rats, as well as a rise in levels in E2-treated rats between 10.00 h and 12.00 h. During the afternoon, TH mRNA expression in most A1 and A2 subdivisions peaked at 14.00 h when LH surge release began. However, in all but the middle and caudal A2 subdivisons, levels were similar in E2-treated and control rats at this time. This was attributable to a widespread increase in TH mRNA expression between 12.00 h and 14.00 h in OVX rats. There was no evidence that E2 induced changes in TH mRNA expression preferentially in regions wherein most neurones contained ER alpha or ER beta mRNA. Our findings suggest that E2 activation of middle and caudal A2 neurones, in conjunction with the widespread E2-independent activation of noradrenergic neurones in other subdivisions, may play a role in the induction of LH surge release.

Optimisation of the CT h4S bioassay for detection of human interleukin-4 secreted by mononuclear cells stimulated by phytohaemaglutinin or by human leukocyte antigen mismatched mixed lymphocyte culture

Limiting dilution analysis has been used in the context of allogeneic bone marrow transplantation to determine anti-recipient interleukin-2 (IL-2) producing helper T lymphocyte precursor (HTLp) frequencies, which in several studies have been predictive of graft-versus-host disease (GVHD). Recently high anti-recipient IL-4 producing HTLp frequencies have been reported and associated with a decreased risk of GVHD. The aim of the present study was to define the optimal conditions for combined determination of IL-2 and IL-4 producing anti-recipient HTLp frequencies. We have optimised the CT.h4S bioassay with regards to specificity, sensitivity, detection limit, and reproducibility. We have found the optimal assay conditions to be 1 x 10 (4) CT.h4S cells/well deprived of IL-4 for 24 h and preincubated for 7 h followed by 18 h of incubation with tritiated methyl-thymidine. In this setting the CT.h4S bioassay detects 5 pg/ml of human recombinant IL-4 with no detection of IL-2 in concentrations below 500 pg/ml. We have found 72 h of culture optimal for detection of IL-2 and IL-4 produced by human mononuclear cells (MNC) in response to stimulation with phytohaemaglutinin and for detection of IL-2 in human leukocyte antigen (HLA)-mismatched mixed leukocyte culture (MLC). An interindividual variation in cytokine accumulation was demonstrated for IL-4 but not for IL-2. With the use of 5x10(4) responder cells/well no IL-4 could be detected in HLA-mismatched MLC between days 1 and 16. The lack of IL-4 detection was not due to high amounts of soluble IL-4 receptor. With the use of 1x10(6) responder cells/well in HLA-mismatched MLC, we found limited IL-4 accumulation still increasing at day 12. We conclude that the CT.h4S bioassay is a reliable and specific method for quantification of IL-4 accumulation in cultures of human MNC. The difference in optimal timing for IL-2 (day 3) and IL-4 (>/=day 12) detection and evidence of very low IL-4 producing HTLp frequencies makes the relevance of a combined IL-2/IL-4 HTLp assay questionable.

Regulation of glutamic acid decarboxylase 65 and 67 gene expression by ovarian steroids: identification of two functionally distinct populations of GABA neurones in the preoptic area

GABA neurones in the preoptic area (POA) are critical for oestradiol (E2)-dependent surge release of luteinizing hormone (LH); however, it is not clear which population(s) of POA GABA neurones is involved. The goals of the present studies were: (i) to determine whether E2 regulates GABA neurones similarly in two subdivisions of the POA that play a role in LH surge release, the rostral POA region that contains the organum vasculosum of the lamina terminalis (rPOA/OVLT), and the region containing the anteroventral periventricular nucleus (AVPV) and medial preoptic nucleus (MPN) and (ii) to determine whether GABA neurones in either or both regions exhibit temporal changes consistent with a role in the regulation of LH surge release. To accomplish these goals, we measured glutamic acid decarboxylase (GAD) 65 and 67 mRNA levels at several time points in ovariectomized (OVX), E2-treated OVX rats exhibiting LH surge release, and in E2-treated OVX rats in which LH surge release was blocked by prior administration of progesterone (P4). Our findings demonstrate that, despite their close proximity, GABA neurones in the AVPV/MPN region are regulated differently from those in the rPOA/OVLT. Only neurones in the AVPV/MPN region show temporal changes in GAD 67 mRNA expression that appear to be linked to positive-feedback effects of E2 on luteinizing hormone-releasing hormone (LHRH) and LH release. Our findings also indicate that a morning rise and an afternoon fall in GAD 67 mRNA levels marks two E2-dependent signals required for LHRH and LH surge release. Finally, our results suggest that there are distinct E2-induced signals to the rPOA/OVLT and AVPV/MPN regions and that these signals differentially regulate GAD 65 and 67 gene expression.

Estrogen receptor-beta immunoreactivity in luteinizing hormone-releasing hormone neurons of the rat brain

Feedback regulation of luteinizing hormone-releasing hormone (LHRH) neurons by estradiol plays important roles in the neuroendocrine control of reproduction. Recently, we found that the majority of LHRH neurons in the rat contain estrogen receptor-beta (ER-beta) mRNA, whereas, they seemed to lack ER-alpha mRNA expression. In addition, we observed nuclear uptake of (125)I-estrogen by a subset of these cells. These data suggest that ER-beta is the chief receptor isoform mediating direct estrogen effects upon LHRH neurons. To verify the translation of ER-beta protein within LHRH cells, the present studies applied dual-label immunocytochemistry (ICC) to free-floating sections obtained from the preoptic area of rats. The improved ICC method using the silver-gold intensification of nickel-diaminobenzidine chromogen, enabled the observation of nuclear ER-beta-immunoreactivity in the majority of LHRH cells. The incidence of ER-beta expression was similarly high in LHRH neurons of ovariectomized female (87.8 +/- 2.3%, mean +/- SEM), estradiol-primed female (74.9 +/- 3.2%) and intact male (85.0 +/- 4.7%) rats. The presence of ER-beta mRNA, ER-beta immunoreactivity and (125)I-estrogen binding sites in LHRH neurons of the rat provide strong support for the notion that these cells are directly regulated by estradiol, through ER-beta. The gene targets and molecular mechanisms of this regulation remain unknown.

Autoreactivity, backstimulation and reproducibility in a helper T lymphocyte precursor assay

Helper T lymphocyte precursor (HTLp) frequencies determined by limiting dilution analysis (LDA) have a predictive value for alloreactivity in allogeneic bone marrow transplantation. Methodological problems in LDA include autoreactivity in the responder or stimulator cell populations and interleukin 2 (IL-2) production by the stimulator cells as a response to the responder cells (backstimulation). The extent and impact of these aspects for IL-2 production and HTLp frequency determination were studied by autologous and allogeneic mixed lymphocyte reactions with healthy volunteers and HTLp determinations from bone marrow transplantation donor/recipient pairs. We found that autoreactivity occurred in the unirradiated cells with a reproducible inter-individual variation. The immunogenicity of the stimulator cells was preserved after gamma irradiation with 50 Gy and the risks of autoreactivity and backstimulation were limited. Higher doses of irradiation decreased the immunogenicity. Immune reactions to antigens present in the serum supplement of the culture medium were seen with foetal calf serum and to a lesser extent with pooled human sera. This could be avoided by the use of autologous serum. We were unable to ensure satisfactory culture conditions in serum-free medium. The reproducibility of the HTLp frequency determinations was tested for intra- and inter-assay variation. The coefficients of variation were estimated as 24% and 35%, respectively. This was acceptable considering the range of the HTLp frequencies (1:10(2) to 1:10(7)). The influence of the extent of autoreactivity of the bone marrow donors was investigated in 28 HLA-identical sibling transplantations. We found no correlation between the autoreactivity of the donors and the HTLp frequencies. The extent of autoreactivity of the donor did not correlate with the clinical outcome in terms of acute graft-versus-host disease, treatment-related mortality, risk of relapse and overall survival. In spite of methodological difficulties and interference from autoreactivity and backstimulation, reproducible quantification of clinically significant alloreactivity can be attained.

Distribution of mRNAs encoding the arylhydrocarbon receptor, arylhydrocarbon receptor nuclear translocator, and arylhydrocarbon receptor nuclear translocator-2 in the rat brain and brainstem

Dioxin exposure alters a variety of neural functions, most likely through activation of the arylhydrocarbon receptor (AhR) pathway. Many of the adverse effects, including disruption of circadian changes in hormone release and depressed appetite, seem to be mediated by hypothalamic and/or brainstem neurons. However, it is unclear whether these effects are direct or indirect, because there have been no comprehensive studies mapping the expression of components of the AhR pathway in the brain. Therefore, we used a sensitive in situ hybridization histochemical (ISHH) method to map the neural expression of AhR mRNA, as well as those of the mRNAs encoding the AhR dimerization partners, arylhydrocarbon receptor nuclear translocator (ARNT) and ARNT2. We found that AhR, ARNT, and ARNT2 mRNAs were widely distributed throughout the brain and brainstem. There was no neuroanatomic evidence that AhR is preferentially colocalized with ARNT or ARNT2. However, ARNT2, unlike ARNT expression, was relatively high in most regions. The most noteworthy regions in which we found AhR, ARNT, and ARNT2 mRNA were several hypothalamic and brainstem regions involved in the regulation of appetite and circadian rhythms, functions that are disrupted by dioxin exposure. These regions included the arcuate nucleus (Arc), ventromedial hypothalamus (VMH), paraventricular nucleus (PVN), suprachiasmatic nucleus (SCN), nucleus of the solitary tract (NTS), and the dorsal and median raphe nuclei. This neuroanatomic information provides important clues as to the sites and mechanisms underlying the previously unexplained effects of dioxins in the central nervous system.

Detection of estrogen receptor-beta messenger ribonucleic acid and 125I-estrogen binding sites in luteinizing hormone-releasing hormone neurons of the rat brain

Luteinizing hormone-releasing hormone (LHRH) neurons of the forebrain play a pivotal role in the neuroendocrine control of reproduction. Although serum estrogen levels influence many aspects of LHRH neuronal activity in the female, earlier studies were unable to detect estrogen receptors (ERs) within LHRH neurons, thus shaping a consensus view that the effects of estradiol on the LHRH neuronal system are mediated by interneurons and/or the glial matrix. The present studies used dual-label in situ hybridization histochemistry (ISHH) and combined LHRH-immunocytochemistry/125I-estrogen binding to readdress the estrogen-receptivity of LHRH neurons in the female rat. In ISHH experiments we found that the majority of LHRH neurons exhibited hybridization signal for the "beta" form of ER (ER-beta). The degree of colocalization was similar in topographically distinct populations of LHRH neurons and was not significantly altered by estradiol (67.2+/-1.8% in ovariectomized and 73.8+/-4.2% in ovariectomized and estradiol-treated rats). In contrast, the mRNA encoding the classical ER-alpha could not be detected within LHRH neurons. In addition, in vivo binding studies using 125I-estrogen revealed a subset of LHRH-immunoreactive neurons (8.8%) which accumulated the radioligand thus providing evidence for the translation of ER protein(s) within these cells. The findings that most LHRH neurons in the female rat express ER-beta mRNA and at least some are capable of binding 125I-estrogen challenge the current opinion that estrogen does not exert direct effects upon the LHRH neuronal system.

Co-expression of melatonin (MEL1a) receptor and arginine vasopressin mRNAs in the Siberian hamster suprachiasmatic nucleus

Durational melatonin signals, cued by the photoperiod and generated by the pineal gland, are processed in the brain to induce seasonally appropriate physiological and behavioural adaptations. The melatonin receptor subtype MEL1a (also known as mt1) appears to regulate seasonal responses. Single label in situ hybridization for MEL1a receptor mRNA revealed labelled cells in several brain regions of Siberian hamsters, including the suprachiasmatic nucleus, the paraventricular nucleus of the thalamus, and the reuniens nucleus of the thalamus. To characterize suprachiasmatic nucleus cells containing MEL1a receptor mRNA, we used 35S-labelled cRNA probes for MEL1a receptor mRNA in combination with digoxigenin-labelled cRNA probes for vasopressin, somatostatin, or orphan retinoid Z receptor beta (RZRbeta; a putative nuclear melatonin receptor). Cells in the suprachiasmatic nucleus that contained MEL1a receptor mRNA also contained mRNAs for vasopressin and RZRbeta, but not for somatostatin. These data suggest that suprachiasmatic nucleus vasopressin cells may respond to melatonin signals, raising the possibility that suprachiasmatic nucleus vasopressin output mediates some of the effects of melatonin on seasonal or circadian responses.

Cerebral and meningeal multiple myeloma after autologous stem cell transplantation. A case report and review of the literature

Meningeal involvement of multiple myeloma is a very rare complication. Defining meningeal myelomatosis (MeM) as the presence of plasma cells in the cerebrospinal fluid in a patient with multiple myeloma, we have found 53 previously reported cases in the literature, where the diagnosis MeM has been made while the patient was alive. Using Kaplan Meier statistics we have found the median survival, from the time of diagnosis of MeM, to be 1.5 months. We report a case with MeM and possible cerebral myeloma shortly after autologous stem cell transplantation, and compare it with earlier published cases.

Prostate gland growth during development is stimulated in both male and female rat fetuses by intrauterine proximity to female fetuses

In rodents, steroid hormones are transported between adjacent fetuses, and male or female fetuses that develop in utero between female fetuses (2F males or 2F females) have higher serum levels of estradiol and lower serum levels of testosterone relative to siblings of the same sex that develop between two male fetuses (2M males or 2M females). The present study was prompted by the prior unexpected finding that as adults, 2F male mice have an enlarged prostate, and increased numbers of prostatic androgen receptors relative to 2M males. We examined prostate development in both male and female rat fetuses from different intrauterine positions using computer-assisted, 3-dimensional reconstruction of the urogenital complex. In males, this included the prostate, seminal vesicles and utricle (a remnant of the Müllerian ducts), while in females it included development of prostatic glandular buds. The mean cross-sectional area of developing prostatic epithelial buds, utricle and seminal vesicles was significantly increased in 2F male relative to 2M male fetuses. In female fetuses, prostatic bud development was significantly more likely to occur in 2F (67%) than in 2M (29%) animals. These findings suggest that the transport of a small supplement of estrogen from adjacent female fetuses enhances androgen-dependent accessory organ development. We also found that mRNAs encoding receptors for both estrogen and androgen were located in the mesenchyme of the developing male prostate. The localization of estrogen and androgen receptor mRNA in this region further suggests that the mesenchymal induction of prostatic epithelial growth involves both hormones. The cranial dorsolateral prostatic buds exhibited the greatest enlargement in 2F males. This region of the developing prostate in rats is comparable (that is the embryonic homologue) to the region exhibiting benign prostatic hyperplasia (BPH) during aging in men. We propose that the potential for pathological regrowth of the prostate during aging is imprinted by estradiol during fetal development.

The effect of low level laser therapy (LLLT) on wound healing in horses

Laser therapy is used in many countries, including South Africa, for the treatment of skin wounds. Low level galium aluminium arsenide (GaAlAs) laser was administered to full thickness skin wounds (3 x 3 cm) induced surgically on the dorsal aspect of the metacarpophalangeal joints of 6 crossbred horses in a randomised, blind, controlled study. Treated wounds that received a daily laser dosage of 2 J/cm2 were compared with nontreated control wounds on the opposite leg. There were no wound complications. Both groups of wounds were cleaned daily using tap water. Wound contraction and epithelialisation were evaluated using photoplanimetry. There were no significant differences in wound contraction or epithelialisation between the laser treated and the control wounds. It was therefore concluded that laser therapy had no clinically significant effect on second intention wound healing in this study.