Stress responses to bacterial and viral mimetics in polycystic ovary syndrome model rats

Polycystic ovary syndrome (PCOS) is associated with an increased risk of psychological distress as well as enhanced responses to psychosocial stress. Recently, it was hypothesized that PCOS patients may be at high risk of novel COVID-19 infections and worse clinical presentations during such infections. Here, we evaluated the effects of PCOS on stress responses to bacterial and viral mimetics using dihydrotestosterone-induced PCOS model rats. Lipopolysaccharide (LPS; a bacterial mimetic) or polyinosinic-polycytidylic acid (Poly-IC; a viral mimetic) was injected into PCOS model rats (PCOS) and non-PCOS rats (control), and the rats' stress responses were evaluated. In the PCOS group, the rats' anorectic and febrile responses to LPS injection were enhanced, whereas their anorectic and febrile responses to Poly-IC injection were unaltered. The PCOS group also exhibited greater changes in peripheral cytokine levels in response to LPS, but not Poly-IC. On the contrary, after the injection of Poly-IC depressed locomotor activity was more evident in the PCOS group, whereas no such changes were observed after LPS injection. These findings indicate that although the stress responses of PCOS model rats to infection may be enhanced, the patterns of change in stress responses and their underlying mechanisms may differ between bacterial and viral infections.

Progesterone treatment reduces food intake and body weight in ovariectomized female rats

While the effects of progesterone on body weight and appetite in pre-menopausal conditions have been well elucidated, its effects in post-menopausal conditions have not been clarified. On the contrary, the effects of estrogen on body weight and appetite in post-menopausal conditions have been well established. In this study, the effects of progesterone treatment on body weight, appetite, and fat mass in ovariectomized rats were evaluated. In addition, the central and/or peripheral levels of oxytocin (OT), leptin, and their receptors, which are potent anorectic factors, were examined. Female rats were ovariectomized and divided into control, progesterone-treated, and estrogen-treated groups. Body weight, food intake, and subcutaneous fat mass were lower in both the progesterone and estrogen groups than in the control group. The estrogen group exhibited higher serum OT levels than the control group, whereas the OT levels of the progesterone and control groups did not differ. The serum leptin levels of both the progesterone and estrogen groups were lower than those of the control group. Gene expression analysis of OT, leptin, and their receptors in the hypothalamus and adipose tissue found few significant differences among the groups. Hypothalamic neuropeptide Y (NPY) and pro-opiomelanocortin (POMC) mRNA levels involved in appetite regulation were slightly altered in the progesterone and estrogen groups. These findings suggest that progesterone treatment may have favorable effects on body weight, appetite, and fat mass regulation in post-menopausal conditions and that the mechanisms underlying these effects of progesterone differ from those underlying the effects of estrogen.

Neuroendocrine Responses to Transvascular Autonomic Modulation: A Modified Balloon Angioplasty in Multiple Sclerosis Patients

Balloon angioplasty (BA) is a treatment modality to correct vascular lesions in multiple sclerosis (MS) patients, who present with chronic cerebrospinal venous insufficiency (CCSVI). We hypothesized that BA clinical benefits stems in part from improvement in cardiovascular autonomic nervous system (ANS) function. We adopted the Transvascular Autonomic Modulation (TVAM), as a modified BA technique, with the objective of further enhancing ANS functional activities. TVAM involved dilation of multiple vascular beds, including IJVs, azygos and renal veins, and application of manual compression. Since the ANS regulates the function of the hypothalamus pituitary (HPA) axis, we examined TVAM effects on HPA axis in MS patients, and determined the relationship between ANS function and HPA activity. The adrenocorticotropic hormone (ACTH) and cortisol serum levels, systolic and diastolic blood pressure (BP), and heart rate variability (HRV) parameters were measured before and 24 h after TVAM procedure in 72 MS patients. Baseline ACTH and cortisol serum levels were lower than normal ranges in 18% and 25% MS patients respectively. The intervention resulted in significant reductions in both ACTH and cortisol (p<0.001), with a more marked ACTH reduction in males compared to females (p<0.001). Post-TVAM BP increased in patients who presented with baseline BP within lower limits of normal ranges, but decreased in patients with baseline BP above the normal ranges. In a univariate analysis, the changes (Δ) in ACTH serum levels correlated weakly, although significantly, with Δ in diastolic BP (r=-0.265, p=0.03), and Δ in cortisol serum levels correlated weakly, but significantly, with Δ in systolic BP (r=-0.283, p=0.01). The observed ACTH and cortisol reductions are counter to the stress-mediated increases in serum levels of these hormones, which are expected following an invasive procedure. The clinical implications of this unexpected response warrant further investigations.

Effect of modified diabetic splenocytes on mice injected with splenocytes from multiple low-dose streptozotocin diabetic donors

Etiological agents of autoimmune processes that have been made nonvirulent by several treatments, i.e., mitomycin C (Mit C), can be used as a vaccine to protect against disease. In this work we studied the effects of splenocytes from diabetic mice on animals that had been injected with modified splenocytes (Mit C-treated splenocytes from multiple low-dose streptozotocin [mld-sz] mice) 15 days before. Splenocytes from mld-sz diabetic donors altered i.p. glucose tolerance and the first peak of insulin secretion pattern when injected into normal singeneic recipients. These effects can be prevented partially (one injection in a vaccine form) or completely (two injections with a 15-day interval) by a previous injection of Mit C-treated mononuclear splenocytes (MS) from mld-sz mice. The fact that control splenocytes previously treated with Mit C were not able to achieve similar results indicates that donor splenocytes have to be diabetic to prevent the disease. On the other hand, Mit C-treated diabetic MS were not effective in preventing the alterations in glucose tolerance and in the pattern of insulin secretion when injected into athymic mice. This suggests that the preventive effect of Mit C-treated diabetic MS injection also implies an active role of the T cells from the recipient mice. Mit C-treated diabetic splenocytes are preferentially trapped by the pancreas and the lymph nodes from recipient mice. Our results show that the impairment in glucose tolerance and in the insulin secretion pattern produced by diabetic splenocyte transfer can be prevented by one or two previous injections of Mit C-modified diabetic splenocytes.

Pregnancy outcome and complications in women with spina bifida

OBJECTIVE

To describe the antenatal complications, mode of delivery and outcome of pregnancy in women with spina bifida.

STUDY DESIGN

Case series of women known to have attended the spina bifida clinic at the Royal Children's Hospital. Medical records, postal questionnaire and telephone interview were utilized to collect data on the effect of pregnancy on the health of women and the effect of spina bifida on pregnancy outcome.

RESULTS

Of 207 women born between 1945 and 1975, 23 reported having a pregnancy, and 17 who had completed pregnancies agreed to participate. The 17 women had a total of 29 pregnancies, with 23 pregnancies progressing to births. Fourteen of 17 women had antenatal admissions, with wheelchair-dependent women requiring more-frequent and longer admissions. Recurrent urinary infections in pregnancy occurred in women with a prior history of urinary infections; stomal problems occurred but were not serious; mobility was reduced for two women during pregnancy, with full recovery afterwards; and preexisting pressure sores worsened during pregnancy. Vaginal deliveries occurred in one in five pregnancies of women who were wheelchair dependent and in ten of eighteen pregnancies in independently mobile women, including seven of eight pregnancies of independently mobile women without ileal conduits. Cesarean sections were accompanied by postoperative complications in 10 women.

CONCLUSION

Women with spina bifida who become pregnant generally have a positive outcome, with relatively low complication rates.

Insulin secretion by pancreas of athymic mice injected with peripheral mononuclear cells from insulin-dependent diabetic patients

We studied the effect of peripheral blood mononuclear cells (PBMNC) from insulin-dependent diabetic (IDDM) children on the insulin secretion pattern of the pancreas from recipient athymic mice. PBMNC from healthy controls or IDDM patients in different stages of disease were injected into athymic mice. PBMNC from newly diagnosed IDDM children elicited basal nonfasting hyperglycemia and in vitro inhibition of the first and second phases of glucose-stimulated insulin secretion in recipient mice. Animals injected with cells from chronically IDDM children showed normoglycemia, abnormal tolerance to glucose, and inhibition of first-phase insulin secretion. Mitomycin C treatment of MNC from IDDM patients abolished insulin secretion inhibition in recipient mice. PBMNC from newly diagnosed and chronically IDDM patients showed positive anti-beta-cell cellular immune aggression. Mice injected with cells from patients during the remission period showed normoglycemia and no alteration of insulin secretion patterns. When relapsed to their former clinical stage, injection of the cells significantly inhibited first-phase glucose-induced insulin secretion in recipients. PBMNC from newly diagnosed IDDM patients were found to migrate to the pancreas of recipient mice preferably as compared with cells from controls. Cells from chronically IDDM patients cultured with concanavalin A (Con A) increased insulin secretion inhibition; despite this, cells from children during the remission period cultured with Con A failed to modify insulin secretion in recipients. These results show that injection of PBMNC from diabetic patients leads to insulin secretion impairment in recipient mice pancreas, and provide a basis for the study of mechanisms involved in the onset and modulation of anti-beta-cell cellular immune aggression induced by human PBMNC.

Beta-cell function in mice injected with mononuclear splenocytes from multiple-dose streptozotocin diabetic mice

Multiple low doses of streptozotocin (mid sz 40 mg/kg/day, five consecutive days) induce autoimmune diabetes in mice. The aim of the present work was to study beta-cell function in mice injected with splenocytes from mid-sz diabetic mice. Mononuclear splenocytes (MS) from control or diabetic donors were injected into syngeneic C57BL/6J healthy mice (5 x 10(7) MS, ip). MS from diabetic donors did not produce basal hyperglycemia, but they induced abnormal ip glucose tolerance in recipient mice. These "diabetic" MS were also preferentially trapped by the recipient's pancreas. Perifused pancreas from mice injected with MS from mid sz-diabetic donors showed a diminished first and second phase of glucose-induced insulin secretion after 15 days of the cell injection. At this time, pancreatic insulin content among MS recipients did not differ from that found in controls or diabetic donors. Diabetic MS treated with Mitomycin C prior to transfer did not inhibit insulin secretion in recipient mice. Injection of MS from mice made diabetic by a single high sz dose (200 mg/kg) did not induce any alterations of the insulin secretion in recipients. There is enough evidence when using athymic and euthymic (BALB/c nu/nu and +/nu) mice to suggest that proliferation of the injected splenocytes enhanced the progression to the diabetic state, and that both donor and recipient T lymphocytes played an important part in this progression. The results suggest that injection of MS from mid sz-diabetic mice interfere with glucose-stimulated insulin secretion in recipient mice and provide a basis for the study of the mechanisms involved in the onset and modulation of autoimmune pancreatic aggression.

Comparison of two new immobilization collars

STUDY OBJECTIVE

To evaluate the limitation of movement of four cervical collars, with emphasis on two new extrication collars.

DESIGN

Ranges of motion permitted by four extrication collars, measured by two goniometric techniques, were compared. Times required to apply each collar were noted and compared.

SETTING

In a laboratory setting, volunteers were asked to flex, extend, laterally bend, and rotate their necks, first without restriction and then with each of the collars applied.

TYPE OF PARTICIPANTS

Participants were healthy volunteers who worked either in the Department of Physical Therapy or in the Emergency Department of Tulane Medical Center Hospital.

INTERVENTIONS

The collars used were the Nec-Loc Extrication Collar, Philadelphia Collar, Philadelphia Red EM Collar with Immobilizer, and Vacuum Splint Cervical Collar.

MEASUREMENTS

Measurements were performed first using the head goniometer and then the hand-held goniometer. Time required for application was measured in seconds. Statistical evaluation was performed using repeated measure analysis of variance and then Newman-Keuls multiple comparison procedure.

MAIN RESULTS

The Vacuum Splint Cervical Collar restricted range of motion of the cervical spine most effectively.

CONCLUSION

A cervical collar with design characteristics similar to the Vacuum Splint Cervical Collar (ie, a rigid collar that incorporates part of the thorax) will restrict movement of the neck more effectively than shorter, less rigid collars.

Rhabdomyosarcoma with focal cartilaginous differentiation (malignant mesenchymoma) of the inferior vena cava

A sarcoma arising from the inferior vena cava occupied the entire lumen of the inferior vena cava, right atrium, hepatic veins and common iliac veins. Its histological appearance was non-specific sarcoma, except for the presence of a few rhabdomyoblasts and some immature cartilaginous tissue. Immunohistochemically, some tumor cells were positive for myoglobin, desmin, HHF-35, and vimentin. Electron microscopy revealed that some tumor cells contained myofilaments and Z bands in the cytoplasm, which are characteristics of rhabdomyosarcoma. The tumor was diagnosed as rhabdomyosarcoma with focal cartilaginous differentiation (malignant mesenchymoma) of the inferior vena cava.

First phase of insulin secretion stimulated by glucose plus theophylline and inhibitory effect of somatostatin in genetically diabetic mice (C57BL/KsJ-mdb)

In a previous study in C57BL/KsJ mdb/mdb mice aged 4 to 12 days we observed a diminished first phase of glucose-induced insulin secretion in vitro, and alterations in the inhibitory effect of somatostatin on insulin secretion. This study explores, using perifused pancreatic slices, whether the reduced B-cell responsiveness to somatostatin in mdb/mdb mice can be overcome upon induction of a biphasic insulin release by using theophylline. Under these conditions our results show: (1) in mdb/mdb mice aged 4 to 6 days, the restoration of the first peak of insulin secretion overcomes the reduced B-cell sensitivity to somatostatin; and (2) in mdb/mdb mice aged 7 to 12 days, the addition of theophylline only causes a partial restoration of B-cell responsiveness to somatostatin, suggesting that other mechanisms could be involved in the progressive impairement of B-cell sensitivity to somatostatin inhibitory effect.

Secretion and effect of somatostatin in early stages of the diabetic syndrome in C57BL/KsJ-mdb mice

In a previous study in C57BL/KsJ (mdb) mice aged 12 to 90 days, we observed alterations in the secretion of insulin and somatostatin and in the inhibitory effect of the latter upon insulin secretion. This study explores whether hormonal alterations are to be found in the very early stages of the diabetic syndrome, i.e. between ages 4 and 12 days. The results demonstrate two distinct phases in the development of the syndrome: up to age 6 days, the perifused slices of pancreata of control animals present biphasic glucose-induced patterns of insulin and somatostatin secretion, whereas the diabetic animals show a diminished first peak of insulin secretion, but a similar pattern of somatostatin secretion, to that of the control animals; between ages 7 and 12 days, the pancreata of diabetic mice exhibit insulin hypersecretion in basal conditions, and an absence of the first secretion peak and insulin hypersecretion in the second phase in response to glucose stimulation. The glucose-induced pattern of somatostatin secretion presents hormonal hypersecretion in both phases. B-cell sensitivity to the inhibitory effect of somatostatin is diminished in mdb mice of the above-mentioned groups, an alteration which becomes more evident as diabetes evolves. The results show that, in very early stages of the evolution of the diabetic syndrome in C57BL/KsJ (mdb) mice, there are already alterations in insulin and somatostatin secretion patterns and in the inhibitory effect of the latter on insulin secretion.

Effect of salicylate poisoning on insulin secretion. Studies on its mechanism of action

Sodium salicylate poisoning increased glucose-induced insulin secretion by slices of rat pancreas. The alpha adrenergic blocker phentolamine, but not salicylate poisoning, overcame the inhibitory effect of epinephrine on insulin secretion. Theophylline (5, 10 and 15 mM) significantly increased the insulin secretion induced by 11 mM glucose. The highest insulin response was obtained when theophylline was used at a 10 mM concentration. However, when pancreas slices from salicylate poisoned rats were used, a 5 mM concentration was sufficient to achieve maximal insulin response. Salicylate poisoning diminished the free tubulin pool, an action that was impaired by imidazole; however, imidazole did not modify the effect of the ionophore A23187. The results suggest that: a) sodium salicylate poisoning increases B-cell response to glucose; b) changes in alpha adrenergic activity are not related to the mechanism of action of salicylate; c) an increment in the cAMP concentration may mediate the stimulatory effect of salicylate poisoning on insulin secretion; d) the effect of salicylate on the microtubular system is indirect and probably mediated through an increment in pancreatic cAMP.

Studies on the Relationship Between Structure of Human IgG and Anti-complementary Activity

Aggregated human IgG which was prepared by incubation in 6 M urea and dialysis against saline (U-IgG) had anti-complementary activity and was capable of increasing vascular permeability and of reacting with rheumatoid factor (RF). U-IgG also fixed to the skin of the guinea pig.

U-IgG was treated with 2-mercaptoethanol (ME) with or without alkylation by monoiodoacetamide (MIA). Treatment of U-IgG with ME and MIA diminished its anti-complementary activity and its ability to fix to the skin of guinea pigs; reactivity with RF was not destroyed by this treatment.

U-IgG was separated into polymer type (pU-IgG) and monomer type (mU-IgG) by Sephadex G-200 column chromatography. pU-IgG showed high anti-complementary activity, reactivity with RF and ability to increase vascular permeability. mU-IgG reacted weakly with RF, was not able to increase vascular permeability and had no anti-complementary activity. Both pU-IgG and mU-IgG fixed to the skin of the guinea pig.