Trophoblast cell-mediated modifications to uterine spiral arteries during early gestation in the macaque

A specialized subset of invasive embryonic cytotrophoblast cells gains access to maternal uterine arteries early in the gestation of higher primates. These cells continue to migrate extensively within the lumina of spiral arteries, converting them to the highly modified uteroplacental arteries of pregnancy. Although trophoblast cell-mediated modifications are considered critical to the progress of normal pregnancy, few studies have addressed the cellular interactions between maternal arteries and embryonic cells in situ. Macaque placentas and endometrial tissues were collected from 12 animals from day 14 of gestation (blastocyst implantation begins on day 9) to day 49. Standard indirect immunoperoxidase methods were used to identify matrix metalloproteinases (MMP-1, MMP-3, MMP-9), cathepsin B, cathepsin D, platelet-endothelial cell adhesion molecule, cytokeratins, smooth muscle actin, CD68, and factor VIII-related antigen. Cytotrophoblast cells were located deep within spiral arteries in each of the specimens examined. In some examples tightly packed clusters of cytotrophoblast occluded the lumina of invaded arteries. Initial penetration of arterial tunica intima was revealed by discontinuities in the staining pattern for factor VIII and cytotrophoblast intrusion was indicated by cytokeratin staining of the trophoblast cells. Continued cytotrophoblast intrusion into the tunica media was apparent by gaps in the smooth muscle. MMP-1, MMP-3, and MMP-9 were localized within intraluminal and intramural cytotrophoblast. By contrast, neither cathepsin B nor cathepsin D were present, although both were seen in uterine macrophages and stromal cells. Upon reaching the surrounding uterine stroma the cytotrophoblast cells ceased migration. As cytotrophoblast accumulated in the arterial wall the vascular lumen expanded. Evidence of cell death was rarely encountered in associated maternal or embryonic tissues. We conclude that intra-arterial cytotrophoblast cells express several proteinases with substrate specificities sufficient to permit independent remodeling of the extracellular matrix comprising uterine artery walls. The remodeling of the arteries, which involves extensive displacement of maternal endothelium and smooth muscle, in addition to degradation and synthesis of extracellular matrix, is accomplished with little evidence of cell death or loss of the integrity of the arteries. This process provides an interesting example of cooperation between different types of interacting tissues from genetically distinct individuals.     

Opioid-mediated responses of dietary protein on reticular motility and plasma insulin

This study explores the effects of infusion of nerve growth factor (NGF) on behavioral outcome and cell death in the septal region using the clinically relevant model of fluid-percussion brain injury in the rat. Animals were subjected to fluid-percussion brain injury and 24 hours later a miniosmotic pump was implanted to infuse NGF (12 animals) or vehicle (12 animals) directly into the region of maximum injury for 2 weeks. Four weeks postinjury the animals were tested for cognitive function using a Morris Water Maze paradigm. Neurological motor function was evaluated over a 4-week postinjury period. The rats receiving NGF infusions had significantly higher memory scores than vehicle-treated animals. Examination of the cholinergic neurons in the medial septal region using choline acetyltransferase immunohistochemistry demonstrated significant cell loss after injury. Infusion of NGF significantly attenuated loss of these cholinergic neurons. A second group of animals was subjected to fluid-percussion brain injury alone (23 rats) or injury followed by NGF infusion (18 rats). These animals were killed between 24 hours and 2 weeks postinjury and the septal region was examined for the presence of apoptotic cells using the terminal deoxynucleotidyl transferase-mediated biotinylated-deoxyuridinetriphosphate nick-end labeling technique. Apoptotic cells were identified as early as 24 hours postinjury; their numbers peaked at 4 and 7 days, and then declined by 14 days. The NGF-treated animals had some apoptotic cells; however, even at 7 days there were significantly fewer of these cells. No significant motor differences were observed between the NGF- and vehicle-treated groups. These data indicate that NGF administration beginning 24 hours after fluid-percussion brain injury has a beneficial effect on cognition and results in sparing of cholinergic septal neurons. These improvements persist after cessation of NGF administration. The beneficial effects of NGF may be related to its ability to attenuate traumatically induced apoptotic cell death.     

Phase I trial of anti-CD3-stimulated CD4+ T cells, infusional interleukin-2, and cyclophosphamide in patients with advanced cancer

PURPOSE: We performed a phase I trial to determine whether in vivo expansion of activated CD4+ T cells was possible in cancer patients. 111Indium labeling was used to observe trafficking patterns of the infused stimulated CD4+ T cells. The influence of cyclophosphamide (CTX) dosing on immunologic outcome was also examined. PATIENTS AND METHODS: Patients with advanced solid tumors or non-Hodgkin's lymphoma received CTX at 300 or 1,000 mg/m2 intravenously (i.v.). Leukapheresis was performed to harvest peripheral-blood mononuclear cells (PBMCs) either just before the CTX dose, or when the patient was either entering or recovering from the leukocyte nadir induced by CTX. An enriched population of CD4+ T cells was obtained by negative selection. The CD4+ T cells were activated ex vivo with anti-CD3, cultured with interleukin-2 (IL-2) for 4 days, and adoptively transferred. After adoptive transfer, patients received IL-2 (9.0 x 10(6) IU/m2/d) by continuous infusion for 7 days. RESULTS: The absolute number of CD4+, CD4+/DR+, and CD4+/CD45RO+ T cells increased in a statistically significant fashion in all cohorts after the first course of therapy. The degree of CD4 expansion was much greater than CD8 expansion, which resulted in a CD4:CD8 ratio that increased in 26 of 31 patients. The greatest in vivo CD4 expansion occurred when cells were harvested as patients entered the CTX-induced nadir. One complete response (CR), two partial responses (PRs), and eight minor responses were observed. Trafficking of 111Indium-labeled CD4 cells to subcutaneous melanoma deposits was also documented. CONCLUSION: CD4+ T cells can be expanded in vivo in cancer patients, which results in increased CD4:CD8 ratios. The timing of pheresis in relation to CTX administration influences the degree of CD4 expansion. Tumor responses with this regimen were observed in a variety of tumors, including melanoma and non-Hodgkin's lymphoma; a high percentage of patients had at least some tumor regression from the regimen that produced the greatest CD4+ T-cell expansion.     

Indicators of platelet turnover in thrombocytopenic infants

Glycocalicin has been found to be a marker of increased platelet turnover, while interleukin-6 may be increased in response to thrombocytopenia. We used these markers to study the pathophysiology of thrombocytopenia in newborn infants. Cord blood platelet counts were obtained from 499 infants. Thrombocytopenic infants (< 100,000/mm3) and a control group had ELISA assays for interleukin-6 and glycocalicin performed. The mean levels of glycocalicin and interleukin-6 were elevated in cord blood of thrombocytopaenic infants. Infants with intrauterine growth restriction and thrombocytopaenia had no detectable glycocalicin in their plasma, despite elevated levels of interleukin-6. This probably reflects impaired thrombopoiesis in these infants.     

The 139H scrapie agent produces hypothalamic neurotoxicity and pancreatic islet histopathology: electron microscopic studies

Neuronal degeneration, along with astrocytosis, spongiform vacuolation, and amyloid (PrPSc) formation, have long been regarded as neuropathological hallmarks of transmissible spongiform encephalopathies (TSEs). In animals, these diseases include; scrapie, transmissible mink encephalopathy, chronic wasting disease, bovine and feline spongiform encephalopathies, and in humans; kuru, Creutzfeldt-Jakob disease (CJD), and Gerstmann-Str?ussler-Scheinker syndrome (GSS). The abnormal amyloid protein, (PrPSc) is toxic to neurons. Our previous studies showed that hamsters treated with 139H scrapie strain developed obesity, and generalized endocrinopathy, including lesions in hypothalamus, pituitary and pancreas. Histochemical and immunocytochemical studies revealed extensive pathological changes in the islets of Langerhans in 139H-infected hamsters, but not in hamsters infected with 263K scrapie strain. Using routine electron microscopy (EM), we have observed more details of lesions in the beta cells of islets of Langerhans in these animals. Cytoplasmic vacuolation occurred, cytoplasmic organelles were found damaged and disrupted, and membranes were occasionally ruptured. The width of endoplasmic reticulum (ER) lumina were 50-150 nm in controls, whereas in 139H-infected hamsters, they wee occasionally increased up to 4000 nm in diameter. Most beta cells showed degranulation. These EM observations suggest that the cellular death seen in the islets of Langerhans in 139H-infected hamsters is due to necrosis, not apoptosis. Since there were no amyloid deposits found in the islet of Langerhans at the EM level, and there were extremely low scrapie infectivity levels and PrPSc levels in pancreas, it is suggested that the changes noted in pancreas were not a direct toxic effect of PrPSc. Instead, our study suggests that scrapie prion protein PrPSc, acting as a neurotoxicant, alters the hypothalamic neuroendocrine regulation of the pancreas.     

The efficacy of Aspergillus niger phytase in rendering phytate phosphorus available for absorption in pigs is influenced by pig physiological status

We performed an experiment with 112 piglets, 32 growing-finishing pigs, and 12 sows during pregnancy and lactation to test the hypotheses that apparent total tract digestibilities of P and Ca as well as the efficacy of Aspergillus niger phytase in rendering phytate P available in pigs depend on pig physiological status. All pigs were fed diets with identical feedstuff composition either without or with added microbial phytase (Natuphos, 500 FTU/kg diet). The diets contained 6.2 g Ca, 4.8 g total P, and 3.7 g phytate P per kilogram, and intrinsic phytase activity of 120 FTU/kg. The digestibility of P increased by 8.3 percentage units when BW of pigs increased from 30 to 60 kg and then remained stable until 100 kg. Pregnant sows had a lower efficiency of P absorption than piglets and growing-finishing pigs. During lactation, the efficiency of P absorption was 3.4 percentage units higher than during pregnancy but was still 6.6 percentage units lower than for growing-finishing pigs. The efficacy of the phytase in generating digestible P decreased in the order or lactating sows, growing-finishing pigs, sows at the end of pregnancy, piglets, and sows at midpregnancy; the average amounts of generated digestible P were 1.03, .83, .74, .66, and .32 g/kg diet, respectively. The addition of phytase to the diet raised apparent Ca digestibility in the piglets and growing-finishing pigs (by 4.6 and 4.0 percentage units, respectively) but not in the sows. We conclude that in the formulation of swine diets the amount of phytase to be added should be tailored to the target category.     

Accelerated repopulation during fractionated irradiation of a murine ovarian carcinoma: downregulation of apoptosis as a possible mechanism

PURPOSE: To test whether accelerated tumor clonogen repopulation occurs during continuous fractionated radiotherapy of a slow-growing mouse ovarian tumor, and if so whether the accelerated rate of repopulation is predicted by the pretreatment potential doubling time, and whether changes in apoptotic response are a possible mechanism for this change. METHODS AND MATERIALS: The rate of clonogen production during fractionated radiotherapy was followed using the tumor-control assay, with an independent determination of the sensitivity to repeated dose fractions in vivo in the absence of repopulation. The pretreatment potential doubling time was measured by bromodeoxyuridine (BrdUrd) labeling and fluorescence measurements. The apoptotic and mitotic indices at various times during treatment were scored histologically. RESULTS: The slow-growing (pretreatment volume doubling time 6 days) ovarian tumor OCA responds to daily irradiation with 6 Gy under hypoxia by negligible tumor clonogen production in the first few days, followed by a change at about 9 days to accelerated repopulation, after which the effective clonogen doubling time Tclon was about 2 days, near the pretreatment Tpot of 1.7 days. Alternative interpretations of the data, such as a change in radiosensitivity vs. a change in the repopulation rate or acceleration at 3 days as opposed to 9 days, were shown to be unlikely. This change was accompanied by a reduced apoptotic response (measured morphometrically). CONCLUSIONS: When sensitivity to fractionated doses has been corrected for in vivo, this slow-growing mouse tumor exhibits a change to accelerated clonogen production during a continuous radiotherapy regimen that is accompanied or preceded by a reduced histologic apoptotic response. Tclon during accelerated repopulation was slightly longer than the pretreatment Tpot.     

The efficacy of the high volume counterpulsation technique at very low levels of aortic pressure

Nitric oxide synthase activity was measured in Langerhans islets isolated from control and streptozotocin diabetic rats. The activity of the enzyme was linear up to 150 micrograms of protein from control rats and was optimal at 0.1 microM calcium, when it was measured after 45 min of incubation at 37 degrees C in the presence of 200 microM arginine. Specific activity of the enzyme was 25 x 10(-4) nmol [3H]citrulline 45 min-1 mg protein-1. Streptozotocin diabetic rats exhibited less enzyme activity both in total pancreas homogenate and in isolated Langerhans islets when compared to control animals. Nitric oxide synthase activity measured in control and diabetic rats 15 days after the last streptozotocin injection in the second group of animals corresponded only to a constitutive enzyme since it was not inhibited by aminoguanidine in any of the mentioned groups. Hyperglycemia in diabetic rats may be the consequence of impaired insulin release caused at least in part by reduced positive modulation mediated by constitutive nitric oxide synthase activity, which was dramatically reduced in islets severely damaged after streptozotocin treatment.     

Post prostatectomy urinary incontinence

The specific incidence rate of post prostatectomy incontinence is difficult to ascertain. However, regardless of the type of prostatectomy, whether it be transurethral, radical retropubic or radical perineal prostatectomy, or the nature of the prostatic disease, several risk factors are common to all. The most significant risk factors include pre-existing detrusor and/or sphincter dysfunction, increasing age, and surgical expertise. Management options include behavioral techniques, pharmacologic therapy, surgical intervention, and other supportive measures. While no definitive preventive measures can be recommended at this time, reducing the incidence of post prostatectomy urinary incontinence should be the goal.