Enhanced protein kinase B/Akt signalling in pituitary tumours

Pituitary tumours have previously been shown to harbour several abnormalities that cause deregulation of the cell cycle, particularly down-regulation of expression of the cyclin-dependent kinase inhibitor p27. However, it has been unclear whether these are the primary initiating events, or are secondary to other more proximate alterations in signalling pathways. In other cellular systems the Akt signalling pathway has been associated with downstream modulation of cell-cycle control. The aim of the present study was to test the hypothesis that Akt signalling is enhanced in pituitary tumours, and to see if changes in Akt expression are related to previous findings on low expression levels of the nuclear cell-cycle inhibitor p27 in pituitary tumours. We examined normal and adenomatous human pituitary tissue for mRNA and protein expression of Akt1, Akt2 and p27, and the activation of Akt, as well the phosphatase involved in the inactivation of Akt, phosphatase and tensin homologue deleted on chromosome 10 (PTEN). In pituitary adenomas Akt1 and Akt2 mRNA were found to be over-expressed compared with normal pituitary, while PTEN transcripts showed similar levels between the two tissue types. Immunohistochemical expression of phospho-Akt was found to be higher in the tumours than normal pituitaries, while the protein expression of nuclear p27 and PTEN was lower in the adenomas. However, the expression of p27 and Akt were not directly correlated. PTEN sequencing revealed no mutation in the coding region of the gene in pituitary adenomas, and thus we did not locate a cause for the increased phosphorylation of Akt. In summary, we have shown over-expression and activation of the Akt pathway in pituitary tumours, and we speculate that cell-cycle changes observed in such tumours are secondary to these more proximate alterations. Since Akt is a major downstream signalling molecule of growth factor-liganded tyrosine kinase receptors, our data are most compatible with an abnormality at this level as the primary driver of pituitary tumorigenesis.

Post-insemination milk progesterone concentration and embryo survival in dairy cows

Logistic regression analysis was used to evaluate the relationship between post-insemination milk progesterone concentration and embryo survival, and between milk yield and milk progesterone concentration. Milk samples were collected on Days 1, 4, 5, 6, and 7 (insemination=Day 0) following 871 inseminations in spring-calving dairy cows. Milk progesterone concentrations were measured by enzyme-immunoassay and pregnancy diagnosis was conducted with transrectal ultrasonography at approximately Day 30. There was a negative linear relationship (P<0.01) between milk progesterone concentration on Day 4 and embryo survival while, in contrast, there was a positive linear and quadratic relationship between milk progesterone concentration on Days 5, 6 and 7 (P<0.05) and also between the rate of change in progesterone concentrations between Days 4 and 7 inclusive and embryo survival (P<0.05). There was a weak negative linear relationship between average daily milk yield at the time of insemination and milk progesterone concentrations (P<0.001). There was no association between many production parameters, including liveweight and body condition score measured at various stages between calving and insemination, and milk progesterone concentration between Days 4 and 7 inclusive (P>0.05). In conclusion, low progesterone during Days 5-7 (after insemination) was associated with low fertility in dairy cows and there were indications of a range of progesterone concentrations within which embryo survival was maximal.

In situ oviduct and uterine pH in cattle

Knowledge of oviduct and uterine pH in cattle is lacking mainly because of the difficulty of accessing these reproductive tissues, which for the oviduct at least necessitates anesthesia. Because halothane anesthesia is known to depress respiratory function and thus increase blood CO2 and decrease pH, oviduct and uterine pH was measured both in the presence and absence of halothane. Using short-term anesthesia with thiopentone only, oviduct pH was measured on days 2-4 of the estrous cycle and uterine pH on days 6 and 8; there was no significant effect of day of the cycle but oviduct pH ( 7.60+/-0.010 ) was greater ( P<0.001 ) than uterine pH ( 6.96+/-0.009 ). Oviduct pH was higher ( P<0.001 ) and uterine pH lower ( P<0.001 ) than venous blood pH ( 7.41+/-0.007 ). Using thiopentone/halothane anesthesia, oviduct pH was measured on days 0, 2, 3, 4 and 6, and uterine pH on days 6, 8 and 14; there was no effect of day of cycle but oviduct pH values were generally higher than uterine values and significantly so ( P<0.001 ) on day 6 where direct comparison was possible. To our knowledge these are the first published in situ measurements of oviduct pH in cattle.

Groin soft tissue tumors?a challenge for local control and reconstruction: A prospective cohort analysis

BACKGROUND AND OBJECTIVES

Groin soft tissue tumors are associated with high local recurrence rates of 16-48% and postoperative complications in 40-68%. Neoadjuvant chemoradiation and aggressive reconstructive techniques were utilized to improve local control and complication rates in this challenging area.

METHODS

Nine patients in this prospective series were treated with neoadjuvant chemoradiation (30 mg IV doxorubicin x 3d followed by 300 cGy/d x 10d) followed by surgery and two patients received radiation (5,000 cGy with tissue spacer) followed by surgery for tumors with a pelvic/retroperitoneal component. Surgery included resection plus reconstruction of the abdominal wall, myocutaneous flaps for large defects, and vascular reconstruction as necessary.

RESULTS

The 11 consecutive patients presented with Stage I (30%), II (40%), or III (30%) disease. Four patients (36%) were operated on for possible incarcerated hernia prior to referral and two (18%) presented with recurrent tumors. Pathology included 10 sarcomas and 1 desmoid tumor; tumor grade was low (30%), moderate (40%), or high (30%). Local control (mean follow-up 55 months; minimum follow-up 36 months) and limb salvage rate was 100%. Minor wound complications not requiring re-operation occurred in three patients, lymphedema in two, and there were no postoperative hernias.

CONCLUSIONS

Preoperative therapy provides excellent local control of groin soft tissue tumors. Current surgical techniques allow extensive resection with limb salvage, dependable primary wound healing and long-term integrity of the abdominal wall.

Macrophage migration inhibitory factor expression is increased in pituitary adenoma cell nuclei

Macrophage migration inhibitory factor (MIF) is an essential regulator of the macrophage responses to endotoxin. MIF also has the ability to override the anti-inflammatory actions of glucocorticoids during an immune response, and is thus an important pro-inflammatory factor. The presence of MIF in cells of the anterior pituitary has been described, and high levels of MIF in other rapidly proliferating tIssues have also been demonstrated. It has been hypothesised that MIF release from these cells is influenced by the hypothalamo-pituitary-adrenal axis, and that ACTH and MIF are released simultaneously to exert counter-regulatory effects on cortisol. However, another intracellular role for MIF has also been suggested as it has been shown that MIF exerts an effect on the inhibitory cell cycle control protein p27 through an interaction with Jab1, a protein implicated in p27 degradation. We studied MIF expression in different normal and adenomatous human pituitary samples using immunohistochemistry and RT-PCR. There was evidence of co-immunoprecipitation of MIF with Jab1, suggesting an interaction of the two proteins. Our results showed that there is increased expression of MIF protein in the nuclei of all pituitary adenomas compared with normal tIssue (P=0.0067), but there was no statistically significant difference in nuclear MIF expression between the different adenoma types. Nuclear MIF expression correlated positively with p27 and its phosphorylated form in normal tIssue (P=0.0028 and P<0.0001); however, this relationship was not seen in the adenoma samples. Cytoplasmic expression of MIF was found to be variable both in normal and adenomatous samples, with no consistent pattern. MIF mRNA was demonstrated to be present in all tumour and normal samples studied. Somatotroph tumours showed higher MIF mRNA expression compared with normal pituitary or other types of adenomas. In conclusion, MIF is expressed in cell nuclei in pituitary adenomas to a greater extent than in normal pituitary tIssue. We speculate that it may play a role in the control of the cell cycle, but whether its higher level in adenomas is a cause or a consequence of the tumorigenic process remains to be clarified.

Dynamic tests in the diagnosis and differential diagnosis of Cushing's syndrome

Cushing's syndrome is an uncommon disorder, but one that often presents diagnostic challenges to the managing physician. Since the 1960's, dynamic tests have been a mainstay of the investigation of this disorder, both to make the diagnosis and then to identify the cause. It is in this latter role that these tests provide the greatest results, particularly in cases of ACTH-dependent disease, where defining the source accurately allows targeted surgery to the pituitary or ectopic lesions. It can, however, be a confusing area, as multiple protocols, and therefore cut-off criteria, often exist for each test, and some tests are now largely redundant. Therefore, in this article we discuss the physiological basis behind each dynamic test, review the different protocols and criteria that have been utilized, and assess how they perform. It will become clear that no single dynamic test used in this condition is 100% reliable for either the diagnosis or differential diagnosis, but the combination of test results, together with the knowledge of an endocrinologist experienced in such cases, provides the best means of correctly assessing patients with Cushing's syndrome.

Amino acid turnover by elongating cattle blastocysts recovered on days 14-16 after insemination

Blastocyst elongation from day 14 to day 16 after insemination coincides with a major phase of embryo loss in cattle. Protein synthesis, reflected in protein content, increases markedly over this period but little is known about the amino acid requirement of elongating blastocysts at this time. Cattle blastocysts produced in vivo were recovered on days 14-16 after insemination and cultured individually for up to 8 h in synthetic oviduct fluid containing a physiological mixture of amino acids plus 1 mmol glutamine l(-1) and 0.1% (w/v) polyvinyl alcohol (SOFaaPVA). After 1, 4 and 8 h in culture, an aliquot of culture medium was removed and the rate of amino acid depletion or production was calculated per unit of protein and per hour of culture. Amino acids were depleted or produced at different rates. Arginine was depleted from the medium at a significant rate (P < 0.05) during all culture periods. Alanine and glutamate were produced at a significant rate (P < 0.05) during all culture periods. The rate of alanine production was significantly greater (P < 0.05) in blastocysts recovered on day 14 compared with days 15 or 16 after insemination. Alanine production and arginine depletion tended to be greater in smaller embryos recovered on day 14 compared with larger and later stage embryos, indicating that earlier stage embryos may have higher metabolic activity than later stage embryos. Qualitatively, the pattern of amino acid consumption and production during elongation was similar to that shown from the zygote to early blastocyst stage.

Amino acid turnover by elongating cattle blastocysts recovered on days 14-16 after insemination

Blastocyst elongation from day 14 to day 16 after insemination coincides with a major phase of embryo loss in cattle. Protein synthesis, reflected in protein content, increases markedly over this period but little is known about the amino acid requirement of elongating blastocysts at this time. Cattle blastocysts produced in vivo were recovered on days 14-16 after insemination and cultured individually for up to 8 h in synthetic oviduct fluid containing a physiological mixture of amino acids plus 1 mmol glutamine l(-1) and 0.1% (w/v) polyvinyl alcohol (SOFaaPVA). After 1, 4 and 8 h in culture, an aliquot of culture medium was removed and the rate of amino acid depletion or production was calculated per unit of protein and per hour of culture. Amino acids were depleted or produced at different rates. Arginine was depleted from the medium at a significant rate (P < 0.05) during all culture periods. Alanine and glutamate were produced at a significant rate (P < 0.05) during all culture periods. The rate of alanine production was significantly greater (P < 0.05) in blastocysts recovered on day 14 compared with days 15 or 16 after insemination. Alanine production and arginine depletion tended to be greater in smaller embryos recovered on day 14 compared with larger and later stage embryos, indicating that earlier stage embryos may have higher metabolic activity than later stage embryos. Qualitatively, the pattern of amino acid consumption and production during elongation was similar to that shown from the zygote to early blastocyst stage.

Effect of elevated systemic concentrations of ammonia and urea on the metabolite and ionic composition of oviductal fluid in cattle

High dietary protein leads to elevated systemic concentrations of ammonia and urea, and these, in turn, have been associated with reduced fertility in cattle. The effect of elevating systemic concentrations of ammonia and urea on the concentrations of electrolytes and nonelectrolytes in bovine oviductal fluid were studied using estrus-synchronized, nulliparous heifers (n = 25). Heifers were randomly assigned to 1 of 3 treatments consisting of jugular vein infusion with either ammonium chloride (n = 8), urea (n = 8), or saline (n = 9). Oviducts were catheterized, and fluid was recovered over a 3-h period on either Day 2 or 8 of the estrous cycle. No difference (P > 0.05) was found in the concentrations of any electrolyte or nonelectrolyte between oviducts ipsi- or contralateral to the corpus luteum. Plasma and oviductal concentrations of urea were increased by infusion with urea (P < 0.001) and ammonium chloride (P < 0.05) but not by saline (P > 0.05). Plasma and oviductal concentrations of ammonia were elevated by infusion with ammonium chloride (P < 0.001) but not by infusion with urea or saline (P > 0.05). No effect (P > 0.05) of treatment was found on oviductal or plasma concentrations of glucose, lactate, magnesium, potassium, or sodium or on plasma concentrations of insulin or progesterone. The concentration of calcium in oviductal fluid was reduced by urea infusion and was negatively associated with systemic and oviductal concentrations of urea. Oviductal concentrations of sodium were higher on Day 8 than on Day 2 (P < 0.05). No effect of sample day was found on any of the other electrolytes or nonelectrolytes measured (P > 0.05). Elevated systemic concentrations of ammonia and urea are unlikely to reduce embryo survival through disruptions in the oviductal environment.

Optimal response criteria for the human CRH test in the differential diagnosis of ACTH-dependent Cushing's syndrome

The CRH test is in widespread use for the differential diagnosis of ACTH-dependent Cushing's syndrome (CS). Despite the greater availability worldwide of human-sequence CRH (hCRH), there are no large series reporting the response criteria that best discriminate between Cushing's disease (CD) and the ectopic ACTH syndrome (EC) when using hCRH, rather than ovine-sequence CRH. We have, therefore, analyzed retrospectively the serum cortisol and plasma ACTH responses to hCRH in patients with ACTH-dependent CS, to develop response criteria that best discriminate between CD and EC. One hundred fifteen consecutive patients with proven ACTH-dependent CS were studied: 101 with CD (78 females; mean age, 40 yr; range, 10-73) and 14 with EC (7 females; mean age, 46 yr; range, 32-69). The response to hCRH was also studied in 30 normal volunteers (NVs; mean age, 29 yr; range, 20-44) with no clinical evidence of CS, and the results were compared. Following basal sampling at -15 and 0 min, hCRH (100 microg iv) was administered via an indwelling forearm cannula at 0900 h and serum cortisol and ACTH were measured at 15-min intervals for 2 h. The mean basal, peak, incremental, and percentage change in the serum cortisol and ACTH at all time points, and combination of time points, were calculated and analyzed to establish the best criteria to discriminate between CD and EC, and also between CD and NVs. The mean serum cortisol concentration in samples obtained at 15 and 30 min after CRH increased by at least 14% above the mean basal in 85 of 100 patients with CD, but in none with EC, giving a sensitivity of 85% at a specificity set at 100%. In contrast, the best plasma ACTH response of a rise of 105%, calculated from the maximal rise, gave only 70% sensitivity at 100% specificity. In the NVs, the maximum cortisol at the mean 15+30 min time point was 615 nmol/liter. Using the 15 and 30 min time points as the reference point, 71 of 100 patients with CD had a rise of serum cortisol greater than 14% and also showed an absolute cortisol level more than 615 nmol/liter. Serum cortisol responses to hCRH can be used to suggest the diagnosis of CD in the majority of patients with this condition, but it should only be used in conjunction with other biochemical and imaging modalities in establishing this important diagnosis. The measurement of plasma ACTH was less helpful in making this distinction, although it may have additional value in excluding ACTH-independent causes of CS. Although we believe that bilateral inferior petrosal sinus sampling remains the single most useful test in discriminating CD from EC in patients with ACTH-dependent CS, hCRH offers rapid diagnostic information and is a useful adjunctive test in establishing the presence of a possible ectopic source.

Reovirus as an oncolytic agent against experimental human malignant gliomas

BACKGROUND

Reovirus is a naturally occurring oncolytic virus that usurps activated Ras-signaling pathways of tumor cells for its replication. Ras pathways are activated in most malignant gliomas via upstream signaling by receptor tyrosine kinases. The purpose of this study was to determine the effectiveness of reovirus as an experimental treatment for malignant gliomas.

METHODS

We investigated whether reovirus would infect and lyse human glioma cell lines in vitro. We also tested the effect of injecting live reovirus in vivo on human gliomas grown subcutaneously or orthotopically (i.e., intracerebrally) in mice. Finally, reovirus was tested ex vivo against low-passage cell lines derived from human glioma specimens. All P values were two-sided.

RESULTS

Reovirus killed 20 (83%) of 24 established malignant glioma cell lines tested. It caused a dramatic and often complete tumor regression in vivo in two subcutaneous (P =.0002 for both U251N and U87) and in two intracerebral (P =.0004 for U251N and P =.0009 for U87) human malignant glioma mouse models. As expected, serious toxic effects were found in these severely immunocompromised hosts. In a less immunocompromised mouse model, a single intratumoral inoculation of live reovirus led to a dramatic prolongation of survival (compared with control mice treated with dead virus; log-rank test, P<.0001 for both U251N and U87 cell lines). The animals treated with live virus also appeared to be healthier and gained body weight (P =.0001). We then tested the ability of reovirus to infect and kill primary cultures of brain tumors removed from patients and found that it killed nine (100%) of nine glioma specimens but none of the cultured meningiomas.

CONCLUSIONS

Reovirus has potent activity against human malignant gliomas in vitro, in vivo, and ex vivo. Oncolysis with reovirus may be a potentially useful treatment for a broad range of human cancers.

Reactive nitrogen species inhibit alveolar epithelial fluid transport after hemorrhagic shock in rats

Our recent experimental work demonstrated that a neutrophil-dependent inflammatory response in the lung prevented the normal up-regulation of alveolar fluid clearance by catecholamines following hemorrhagic shock. In this study, we tested the hypothesis that the release of NO within the airspaces of the lung was responsible for the shock-mediated failure of the alveolar epithelium to respond to catecholamines in rats. Hemorrhagic shock was associated with an inducible NO synthase (iNOS)-dependent increase in the lung production of NO and a failure of the alveolar epithelium to up-regulate vectorial fluid transport in response to beta-adrenergic agonists. Inhibition of iNOS restored the normal catecholamine-mediated up-regulation of alveolar liquid clearance. Airspace instillation of dibutyryl cAMP, a stable analog of cAMP, restored the normal fluid transport capacity of the alveolar epithelium after prolonged hemorrhagic shock, whereas direct stimulation of adenyl cyclase by forskolin had no effect. Pretreatment with pyrrolidine dithiocarbamate or sulfasalazine attenuated the iNOS-dependent production of NO in the lung and restored the normal up-regulation of alveolar fluid clearance by catecholamines after prolonged hemorrhagic shock. Based on in vitro studies with an alveolar epithelial cell line, A549 cells, the effect of sulfasalazine appeared to be mediated in part by inhibition of NF-kappaB activation, and the protective effect was mediated by the inhibition of IkappaBalpha protein degradation. In summary, these results provide the first in vivo evidence that NO, released within the airspaces of the lung probably secondary to the NF-kappaB-dependent activation of iNOS, is a major proximal inflammatory mediator that limits the rate of alveolar epithelial transport after prolonged hemorrhagic shock by directly impairing the function of membrane proteins involved in the beta-adrenergic receptor-cAMP signaling pathway in alveolar epithelium.

Protein synthesis and phosphorylation by elongating 13-15-day-old cattle blastocysts

Most early embryonic loss in cattle occurs during the period of blastocyst formation and elongation. In this study de novo protein synthesis and phosphorylation by 13-15-day-old cattle blastocysts was determined. Blastocysts were classified by dimension into spherical, ovoid and elongated stages and cultured under oil for 4 h in drops of KSOM medium containing either 35S-methionine or 32P-orthophosphate. Protein content increased with shape from spherical to ovoid to elongated. There were differences (P<0.05) within and among days in the percentage of radiolabel incorporated. Incorporation of 35S-methionine increased with embryo protein content. However, incorporation of 35S-methionine into TCA-insoluble material, expressed per microg of protein, decreased with shape (P<0.001) with more than a 10-fold difference between spherical and elongated 13-day-old blastocysts. Incorporation of 32P-orthophosphate also tended to decrease with shape, with a 3-fold difference between spherical and elongated Day 13 blastocysts. It was concluded that, from Day 13, protein synthesis and phosphorylation, when expressed per unit of protein, decreased from a much higher level, which in the present study was around the time the blastocysts began to elongate.

Using telemedicine to facilitate training in cardiotocography (CTG) interpretation

Electronic fetal monitoring is a controversial practice in modern obstetric care and is frequently an aspect of medicolegal cases involving the management of labour and delivery. The interpretation of the cardiotocograph (CTG) produced by such monitors is a skill required by those caring for the pregnant woman. Studies have shown that most 'experts' do not interpret CTGs in a consistent manner, when compared with either other experts or themselves. However, it has also been shown that consistency can be improved with training. Telemedicine has been used to advantage in the training of obstetrics and gynaecology registrars in CTG interpretation.

Enhancement of an antenatal diagnosis and counselling service (ADACS) through the ready availability of telemedicine services

The early diagnosis of fetal abnormalities and their consequent management comprise a relatively new specialty, which has developed to a large extent from the advances in and availability of ultrasound imaging techniques. The Women's and Children's antenatal diagnosis and counselling service (ADACS) is composed of a multidisciplinary group of health professionals and deals with issues relating to pre-pregnancy counselling, fetal diagnosis of abnormalities and the management of these conditions, including all aspects of pregnancy loss. Detailed minutes are recorded for each case and key information is stored in a relational database. Weekly meetings are held to discuss selected cases and, where possible, are presented to the group by the referring practitioner, either in person or using the telemedicine facilities. Telemedicine has provided a significant enhancement to the ADACS service.

Mobile intensive care services in rural South Australia

In the 12 years from 1984 to 1995, Adelaide-based mobile intensive care teams transported 4443 critically ill patients from rural areas in South Australia and adjacent States to tertiary-level hospitals in Adelaide. The SA Ambulance Service undertook communications, support staffing and deployment of transport. Average radial distances in 819 road missions were 71 km, in 808 helicopter missions 122 km, and in 2777 fixed-wing aircraft missions 398 km. The largest groups of patients were neonates (23%) and those with trauma (25%). Rural hospitals made 96% of the requests for intensive care transport; 4% came from ambulance or other emergency service crews at accident locations. Emergency surgical or operative obstetrical procedures were performed on 2.7% of patients before transport. One hundred and thirteen patients (2.5%) died during resuscitation or transport, with one death deemed to be preventable.

The enhancement of audience participation in telemedicine education by the use of electronic voting

The rotation of trainee registrars in obstetrics and gynaecology to peripheral centres in South Australia was introduced for the first time in January 1998. A pilot study of the use of telemedicine to maintain the trainees' involvement in the established weekly training sessions conducted at the Women's and Children's Hospital (WCH) was also commenced at the same time. Sessions were problem based and required the trainees to be actively involved throughout. An electronic voting system (EVS) was used by the WCH audience, with the results of all responses being seen at the peripheral centres. Initial evaluation of the EVS as an educational tool was sufficiently positive to justify further studies of its use in this environment. The availability of voting units at the peripheral sites, used in conjunction with the main centre, will provide an exciting opportunity for further research.

Gelatinase-A (MMP-2), gelatinase-B (MMP-9) and membrane type matrix metalloproteinase-1 (MT1-MMP) are involved in different aspects of the pathophysiology of malignant gliomas

Matrix metalloproteinases (MMPs) have been implicated as important factors in gliomas since they may both facilitate invasion into the surrounding brain and participate in neovascularization. We have tested the hypothesis that deregulated expression of gelatinase-A or B, or an activator of gelatinase-A, MT1-MMP, may contribute directly to human gliomas by quantifying the expression of these MMPs in 46 brain tumour specimens and seven control tissues. Quantitative RT-PCR and gelatin zymography showed that gelatinase-A in glioma specimens was higher than in normal tissue; these were significantly elevated in low grade gliomas and remained elevated in GBMs. Gelatinase-B transcript and activity levels were also higher than in normal brain and more strongly correlated with tumour grade. We did not see a close relationship between the levels of expression of MT1-MMP mRNA and amounts of activated gelatinase-A. In situ hybridization localized gelatinase-A and MT1-MMP transcripts to normal neuronal and glia, malignant glioma cells and blood vessels. In contrast, gelatinase-B showed a more restricted pattern of expression; it was strongly expressed in blood vessels at proliferating margins, as well as tumour cells in some cases. These data suggest that gelatinase-A, -B and MT1-MMP are important in the pathophysiology of human gliomas. The primary role of gelatinase-B may lie in remodelling associated with neovascularization, whereas gelatinase-A and MT1-MMP may be involved in both glial invasion and angiogenesis. © 1999 Cancer Research Campaign

Gelatinase-A (MMP-2), gelatinase-B (MMP-9) and membrane type matrix metalloproteinase-1 (MT1-MMP) are involved in different aspects of the pathophysiology of malignant gliomas

Matrix metalloproteinases (MMPs) have been implicated as important factors in gliomas since they may both facilitate invasion into the surrounding brain and participate in neovascularization. We have tested the hypothesis that deregulated expression of gelatinase-A or B, or an activator of gelatinase-A, MT1-MMP, may contribute directly to human gliomas by quantifying the expression of these MMPs in 46 brain tumour specimens and seven control tissues. Quantitative RT-PCR and gelatin zymography showed that gelatinase-A in glioma specimens was higher than in normal tissue; these were significantly elevated in low grade gliomas and remained elevated in GBMs. Gelatinase-B transcript and activity levels were also higher than in normal brain and more strongly correlated with tumour grade. We did not see a close relationship between the levels of expression of MT1-MMP mRNA and amounts of activated gelatinase-A. In situ hybridization localized gelatinase-A and MT1-MMP transcripts to normal neuronal and glia, malignant glioma cells and blood vessels. In contrast, gelatinase-B showed a more restricted pattern of expression; it was strongly expressed in blood vessels at proliferating margins, as well as tumour cells in some cases. These data suggest that gelatinase-A, -B and MT1-MMP are important in the pathophysiology of human gliomas. The primary role of gelatinase-B may lie in remodelling associated with neovascularization, whereas gelatinase-A and MT1-MMP may be involved in both glial invasion and angiogenesis.

Role of conducting polymeric interfaces in promoting biological electron transfer

In this paper, we explore the role that polymer conductivity and functionality play in determining the nature of molecular recognition at artificial polymer interfaces, as evidenced by electron transfer with the small redox protein, cytochrome c. The relationship is investigated electrochemically using cyclic voltammetry in order to assess the degree of molecular recognition between the biological molecule and carboxyl-functionalized beta-substituted poly(thiophenes) and poly(pyrroles), as well as a co-polymer matrix of these derivatives. In the latter case, the co-polymer film was analysed quantitatively using X-ray photoelectron spectroscopy, and it was found that its composition did not reflect the initial molar ratios of the monomers prior to electrodeposition.

Effect of peptide to carrier ratio on the immune and ovarian response to inhibin immunization in cattle

We report on the effects of the peptide to carrier ratio on the immune and biological response to inhibin immunization in cattle. A peptide sequence from the alpha C-subunit of bovine inhibin was synthesized and conjugated to human serum albumin (HSA) at ratios of 4.3 moles (L) and 13.1 moles (M) of peptide per mole of HSA. Hereford-cross heifers (n = 6 per group) were injected with 3 mg of one of the peptide conjugates at primary, followed by a booster injection (1.5 mg) 11 weeks later. Control heifers (n = 6) were injected with HSA only. Blood samples were taken at regular intervals to measure antibody titre. Ovulation rate was measured by ultrasonography. Antibodies were generated in both peptide immunized groups. Control heifers and group L heifers had 1 ovulation at all ovulatory cycles monitored. Ovulation rate was increased (P < 0.05) in group M immunized heifers, with four of six heifers having twin ovulations in the first cycle following boost. These data support those of previous studies which indicated that immunization against the alpha C-subunit of bovine inhibin significantly disrupted the mechanism(s) controlling ovulation rate in cattle. It also indicates that both the immune and associated biological response is dependent on the nature of the conjugate used for immunization, specifically the ratio of peptide to carrier.

Effect of immunization against synthetic peptide sequences of the alpha N-subunit of bovine inhibin on ovulation rate, gonadotrophin concentrations and fertility in heifers

The effects of immunizing cattle against either of two peptides from the amino terminal peptide (alpha N) of the alpha 43-subunit of bovine inhibin on ovulation rate, gonadotrophin concentration and fertility were investigated. Two peptide sequences from the alpha N-subunit of bovine inhibin (P1N, bI alpha-(8-20) and P2N, bI alpha-(153-167)) were synthesized and conjugated to human serum albumin (HSA). Hereford-cross heifers (n = 5 per group) were given an initial injection of 3 mg of one of the peptide conjugates, followed by three booster injections (1.5 mg) at intervals of 11 weeks. Control heifers (n = 5) were injected with HSA only. Blood samples were taken once a week to measure antibody titre and every hour at about the time of the first oestrus and during the mid-luteal phase after the second booster injection, to measure FSH and LH concentrations. Ovulation rate was measured by ultrasonography. Gonadotrophin concentrations were analysed for four periods relative to the peak (time = 0 h) of the preovulatory LH surge as follows: pre-surge: -16 to -5 h; surge: -4 to 4 h; post-surge: 5 to 16 h and a period of 12 h during the mid-luteal (days 10-12) phase. Antibodies that bound to the individual peptides were generated and the ovulation rate increased (P < 0.05) in immunized heifers. Control heifers had one ovulation at all ovulatory cycles monitored. In group P1N, one heifer had two ovulations at each of the six cycles monitored, while another heifer had two ovulations at one cycle.(ABSTRACT TRUNCATED AT 250 WORDS)

Ethanol affects sympathetic cotransmission and endothelium-dependent relaxation in the rat

The influence of ethanol on sympathetic nerve-mediated contractions of rat tail arteries and on endothelium-dependent relaxation of rat mesenteric arteries by acetylcholine was examined using the method of in vitro pharmacology. Ethanol potentiated sympathetic nerve-mediated contractions. Ethanol had no effect on the neurogenic contractions that remained after alpha-adrenoceptor blockade by prazosin. However, after P2x-purinoceptor desensitisation, the residual nerve-mediated contractions were significantly enhanced by ethanol. Contractions to exogenous noradrenaline and alpha,beta-methylene ATP were unaffected by ethanol. It is concluded that ethanol selectively potentiates the noradrenergic component of sympathetic neurotransmission. Ethanol depressed the relaxation by acetylcholine but not that induced by sodium nitroprusside. These results indicate that ethanol can affect both the neural and endothelial control of vascular tone. The potentiated noradrenergic vasoconstrictor response to sympathetic nerve stimulation and the compromised capacity of the endothelium to cause relaxation after ethanol treatment may contribute to the development of vascular diseases associated with alcohol consumption.

Common ring motifs in proteins involving asparagine or glutamine amide groups hydrogen-bonded to main-chain atoms

We report the frequent occurrence in proteins of motifs consisting of either 9-membered or 11-membered rings that involve the side-chain amide groups of asparagine and glutamine residues. The syn CO and NH groups of these amide groups are hydrogen-bonded to the main-chain NH and CO groups of other amino acid residues. The main-chain part of both the 9-membered and 11-membered rings has the conformation of a beta-strand. One such ring motifs occurs, on average, in half of all the proteins we examined. Similar conformations are found for most examples of the 9-membered and 11-membered rings. One of the 11-membered rings is distinct, compared to the others, in that its main-chain part has a mirror-image conformation. Another of the 11-membered rings occurs at the interior of the variable domains of some antibodies and assists in linking the two beta-sheets. We observe one 9-membered ring structure in a dihydrofolate reductase complex in which the amide in the nicotinamide group of the ligand NADP is bound to the enzyme. Groups that can form hydrogen bonds in a similar way to amide groups occur in several nucleotide bases; we find one example of a 9-membered ring involving adenine and main-chain atoms in the FAD-protein complex of glutathione reductase. Both have conformations like those of the other 9-membered rings.

Lymphoproliferative disease of "LAK cell" precursor large granular lymphocytes in association with celiac disease

We have investigated a case of lymphoproliferative disease of large granular lymphocytes (LDGL) occurring in association with celiac disease, anemia, neutropenia, and carcinomas of the endometrium, breast, and skin. The large granular lymphocyte (LGL) proliferation was monoclonal, T cell in origin, with T cell receptor beta-chain gene rearrangement, and a CD3+, CD8+, CD16+/- phenotype. In spite of the high frequency of LGL, natural killer (NK) cell activity was absent. Stimulation with interleukin-2 in vitro, however, resulted in high lymphokine-activated killer (LAK) cell activity against NK-resistant targets. The T-cell nature of the LAK precursor cells is in contrast to the majority seen in normal peripheral blood. Therapeutic trials of cyclosporin A, low-dose cyclophosphamide, and levamisole were unsuccessful in reducing transfusion requirements. This case is unique in the association of LDGL with celiac disease. It is also unique in that the patient had been followed for several years prior to the onset of the LDGL. The case extends the list of lymphoproliferative disorders documented to be associated with celiac disease and, conversely, adds to our knowledge of lymphoproliferative disorder of LGL and its "dysimmune" manifestations.

Effect of immunization against synthetic peptide sequences of bovine inhibin alpha-subunit on ovulation rate and twin-calving rate in heifers

Three peptide sequences from the bovine inhibin alpha-subunit (P1: 18-30; P2: 63-72 and P3: 107-122) were synthesized and conjugated to human serum albumin (HSA). Hereford cross-heifers (n = 5 per group) were injected with 3 mg of one of the peptide conjugates, followed by three booster injections at intervals of 11 weeks. Control heifers (n = 5) were injected with HSA only. Antibodies recognizing both the individual peptides and 32 kDa bovine inhibin were generated and ovulation rate was increased in peptide immunized heifers. In group P1, 1 of 5 heifers responded with an increased ovulation rate whereas in groups P2 and P3, 5 of 5 and 4 of 5 heifers, respectively, had an increased ovulation rate. In group P2, in the first oestrous cycle following booster injections 2 and 3, 4 of 5 and 3 of 5 heifers, respectively, responded with twin ovulations, whereas a fourth heifer had three ovulations following booster injection 3. After breeding following booster injection 3, 3 of 5 heifers in group P2 and 1 of 5 in group P3 gave birth to twin calves. This study demonstrates the potential of immunizing against synthetic peptide sequences of the alpha-subunit of bovine inhibin to increase ovulation and twinning rates in cattle.

Effect of immunizing prepuberal lambs of low and high ovulation rate genotypes with inhibin partially purified from bovine follicular fluid

Active immunization of prepuberal lambs with a partially purified inhibin preparation, isolated from bovine follicular fluid, increased the ovulation rate. In ewe lambs of a low fecundity breed (Suffolk x Galway), the ovulation rate rose from 1.15 to 1.95 (P<0.05) compared with that of the controls. An ovulation rate of 3.38 was recorded for immunized ewe lambs of a high fecundity breed (Finn x Dorset Horn), while the rate for mature ewes from the same flock was 2.29. Immunization did not affect the time of onset of puberty or estrous cycle length. Following immunization, antibodies were produced that bound to a pure preparation of 68kDa bovine inhibin. This report demonstrates the production of antibody to a 68kDa preparation of inhibin following active immunization of sheep using a partially purified preparation. It was concluded that the increased ovulation rate was due to the production of antibodies to inhibin, which may have reduced its negative feedback effect of FSH secretion.

Tests of fetal welfare

The importance of maternal recording of fetal movements is emphasised by the authors and the value of ultrasound and cardiotocography for follow up examination is discussed. The newer modalities of flow velocity waveforms and cordocentesis should be reserved for specialist units. Other important tests include fetal heart rate monitoring and scalp blood monitoring, and their uses and limitations are reviewed.

Studies of lymphokine-activated killer (LAK) cells. I. Evidence using novel monoclonal antibodies that most human LAK precursor cells share a common surface marker

Separation of LAK precursor (LAKp) cells (as defined by LAK effector generation after incubation with IL-2 for 7 d) from cells with NK activity/LGL morphology was achieved on Percoll gradients using a longer, slower centrifugation than that used for optimal NK enrichment. mAb were generated using the various Percoll fractions as the immunizing cells and used for separation and depletion studies. Two mAbs DM-1 (IgM,k) and DM-2 (IgM,k) recognizing 2-15% and 15-30% of PBL, respectively, abrogated a large proportion of LAK generative potential after complement depletion, but had little effect on NK or LAK effector activity. Cell sorting experiments indicated that the majority of LAKp cells are found within the DM-1+ population and that DM-1+ cells are not simply an accessory cell required for LAKp generation. Further, these two mAbs do not recognize cells that are responsible for generating cytotoxicity during MLC or co-culture with the PR-1 EBV lymphoblastoid cell line. Western blot analysis indicated that DM-1 and DM-2 recognize a 38,000 and 44,000 dalton moiety, respectively. The frequency of cells bearing these antigens and the intensity of cell surface staining decreased during the 7-d culture period, suggesting that these antibodies recognize determinants found only at the precursor level. These findings indicate that cells other than NK effectors or mature T cells are capable of generating a LAK cell response. These LAK precursor cells share a common differentiation surface antigen and are different from AK or antigen-specific CTL precursors. The possibility exists that these cells are identical to, or include, the NK precursor cell.

Video recording in an acute care perinatology unit

Intensive care of the newborn is usually unexpected, often involves emergency retrieval, is sometimes administered in life-threatening disorders, and is always extremely anxiety-provoking and disruptive for the families involved. All this occurs at a time when mother-infant bonding is so important. The use of a video-recording system in these acute care situations is described, with particular case examples illustrating its value.

Metastases to the adrenal glands and the development of Addison's disease

Metastases to the adrenal glands are common in patients with cancer but symptomatic Addison's disease is rarely noted in this population. The development of body computerized tomography (CT) allows the diagnosis of adrenal metastases to be made more readily antemortem. From 1980 to 1981, 19% (4/21) of patients at the Massachusetts General Hospital who had metastatic cancer and who were noted to have enlarged adrenal glands on CT also had or developed symptomatic adrenal insufficiency. The case histories of 8 patients with Addison's disease and one patient with adrenal hemorrhage on the basis of metastatic infiltration are reviewed. Since adrenal insufficiency may develop abruptly in this group of patients, it is suggested that prophylactic maintenance glucocorticoid therapy be initiated as soon as the diagnosis of adrenal metastases is made.

Anisochrony induced by transmission of chirality across a triple bond

In the substituted camphors (2) and (3), the chiral bicyclic moiety causes anisochrony of the geminal methyl groups from which it is separated by an ethynylic group.

Development of functional motor innervation in supernumerary hindlimbs of the chick embryo

1. The development of functional motor innervation in supernumerary chick hindlimbs transplated to host embryos at stages 16--18, was studied throughout the embryonic period from stage 27 when peripheral synapses were first formed. 2. The innervation pattern, defined as the number and sequential order of spinal nerves innervating individual muscles, were determined for supernumerary hindlimbs innervated by thoracic, lumbosacral-thoracic, or wholly lumbosacral spinal cord segments. Spinal nerves were electrically stimulated and muscle contraction was scored visually or by tension measurement and compound action-potential recordings were made from muscle nerves. 3. There was no tendency for spinal nerves to grow to or to synapse with the muscles which they normally innervate. Rather, they formed functional connections with inappropriate muscles, which were maintained throughout the developmental period studied. The localization of the motoneuron cell bodies was confirmed with retrograde transport of horseradish peroxidase (HRP) and shown to be adjacent to the spinal nerves through which their axons exited. Motoneurons innervating specific muscles occupied a similar medial-to-lateral position in the cord in both control and supernumerary limbs. 4. In all supernumerary limbs a definite peripheral innervation pattern was formed, which approximated the normal pattern. Specifically, the relative craniocaudal position of motor columns innervating individual muscles was conserved, even though the actual spinal nerves innervating the transplant were different from animal to animal. In limbs reversed along the anterior-posterior axis, the innervation pattern was also reversed. 5. The results suggest that motoneurons have not been rigidly specified to innervate certain muscles at the time when the limb buds were transplanted. Further, the limb itself can apparently influence the innervation pattern in an important manner, possibly by specifying motoneurons or by subsequently directing axon outgrowth and synapse formation.

Long range proton-proton coupling in endo-3,4-Disubstituted bornanones

The coupling constant 4Jexo.H 3exo-H 5 of 3,4-disubstituted bornanones increases or decreases depending on the point of attachment of substituents.

The development of functional innervation in the hind limb of the chick embryo

1. The development of functional motor innervation was studied in the hind limb of chick embryos from Stages 25 to 43 by observing contraction of individual muscles and by recording the resultant tension when individual spinal nerves were electrically stimulated. 2. At later developmental stages (35-43) a given muscle always received functional innervation from specific spinal nerves. This pattern, with respect to the craniocaudal position of motoneurones, was similar to those described for amphibians and mammals. 3. The observed pattern was similar throughout development from the time that movement could first be elicited at Stages 27-28. There was no indication that motoneurones form initial synapses with inappropriate muscles. 4. Recordings from muscle nerves during excitation of individual spinal nerves gave results similar to the tension recordings, showing that even at early developmental stages muscle nerves did not contain substantial numbers of inappropriate axons. 5. Most limb muscles or primitive muscle masses became functionally innervated at the same time with no clearly defined proximo-distal sequence of limb innervation. 6. It appears that chick motoneurones are initially specified with respect to their peripheral destination and grow out selectively to synapse with appropriate muscles from the outset.