Minimally invasive neonatal surgery

Minimally invasive surgery is now an option to patients as light as 1.2 kg, extending the benefits of small incisions, faster recoveries, decreased pain, and more precise procedures in critically ill neonates. This article provides a review of the historical development of minimally invasive surgery and an overview of the equipment involved, identifies the roles of the neonatal and perioperative nurse, and briefly describes several minimally invasive surgery procedures currently performed in the neonatal population.     

Manganese induces spreading and process outgrowth in rat pheochromocytoma (PC12) cells

Mn²⁺ has been shown to promote cell–substrate adhesion and cell spreading in many cell culture systems. In this study, we present data demonstrating that Mn²⁺ not only promotes spreading, but also induces process outgrowth in rat pheochromocytoma (PC12) cells. In the presence of 1.0 mM MnCl₂, cell spreading was apparent by 6 hr, and nearly 50% of the exposed cells extended neurite-like processes. These morphological effects of Mn²⁺ were both time- and dose-dependent. In the presence of cycloheximide, a protein synthesis inhibitor, both Mn²⁺-induced spreading and neurite outgrowth were prevented, indicating that de novo protein synthesis is required for the effects of Mn²⁺ to take place. Of the other divalent cations tested, Mg²⁺, Cd²⁺, Cu²⁺, Ni²⁺, and Zn²⁺ were ineffective, and only Co²⁺ partially mimicked the effects of Mn²⁺. Although Mn²⁺-induced cell adhesion and spreading have been extensively studied, this is the first report that this divalent cation can cause neurite outgrowth. The neurite outgrowth-promoting effects of Mn²⁺ were distinct from those of nerve growth factor in that the response to Mn²⁺ was considerably more rapid, but apparently lacked the ability to sustain continuous outgrowth and networking of neurites. Mn²⁺ also induced the levels of GAP-43 and peripherin, two proteins associated with neuronal differentiation of PC-12 cells. In cells grown in serum-free defined medium, Mn²⁺ was capable of promoting neurite outgrowth when the cells were plated on surfaces pretreated with normal growth medium, vitronectin, or fibronectin, while it failed to cause these morphological changes in cells plated on untreated or poly-D-lysine-coated substrata. Similarly, Mn²⁺ also promoted neurite outgrowth from rat sympathetic neurons attached to laminin-treated substrate, but had no effect on neurons maintained on substrate with polylysine only. The pentapeptide Gly-Arg-Gly-Asp-Ser nearly completely prevented the morphological effects of Mn²⁺ on PC12 cells. These findings are consistent with a hypothesis that Mn²⁺-mediated alteration of an RGD-dependent extracellular matrix-integrin interaction is responsible for the neuritogenic effects. © 1993 Wiley-Liss, Inc.     

Beneficial effect of tachykinin NK1 receptor antagonism in the development of hapten-induced colitis in mice

The gastro-intestinal tract is highly innervated by both intrinsic and extrinsic sensory nerves and this neuronal component is thought to play a role in local inflammatory responses. This in vivo study was designed to determine the function of substance P and the tachykinin NK1 receptor in the pathogenesis of inflammatory bowel disease by the use of the specific antagonist RP 67580. The dinitrofluorobenzene (DNFB)-induced colonic hypersensitivity model is associated with increased levels of substance P in the colon. The tachykinin NK1 receptor antagonist RP 67580 was used to investigate the role of substance P on the development of diarrhea, mast cell infiltration and activation, colonic tissue damage, hypertrophy of colonic lymphoid structures and leukocyte infiltration. The formation of watery diarrhea could completely be abrogated by treatment with RP 67580 in DNFB-sensitized animals 72 h after challenge. Antagonizing the tachykinin NK1 receptor in these animals also resulted in significantly reduced colonic patch hypertrophy, leukocyte recruitment and tissue damage. Total levels of substance P in the colon of DNFB-sensitized mice treated with the inactive enantiomer of the tachykinin NK1 receptor antagonist were significantly higher compared to DNFB-sensitized mice treated with RP 67580 72 h after challenge. Although RP 67580 was capable of reducing the total number of mast cells present in the colon, mast cell activation was not affected by this treatment. In conclusion, in this chemically-induced immunological model for inflammatory bowel disease we demonstrated an important role for tachykinin NK1 receptors, and its ligand substance P, in the development of colitis downstream from mast cell activation.     

The magnitude and duration of post-exercise hypotension after land and water exercises

The objective of the study was to determine and compare the magnitude and duration of post-exercise hypotension (PEH) during free-living conditions after an acute session of concurrent water and land exercise in individuals with prehypertension and hypertension. Twenty-one men and women (aged 52?±?10?years) volunteered for the study. Participants completed a no exercise control session, a water exercise session and a land exercise session in random order. After all three sessions, participants underwent 24-h monitoring using an Ergoscan ambulatory BP monitoring device. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were monitored to determine changes from resting values after each session and to compare the PEH responses between land and water exercises. During daytime, both land and water exercises resulted in significantly lower SBP (12.7 and 11.3?mmHg) compared to the control session (2.3?mmHg). The PEH response lasted for 24?h after land exercise and 9?h after water exercise. There was no difference in the daytime DBP for the three treatments (P?>?0.05). Although all three groups showed significant reductions during nighttime, both exercise treatments showed greater nocturnal falls in BP than the control treatment. This is the first study to show that the magnitude of the PEH response is similar for land and water exercises, although the duration of PEH may be longer for land exercise. These results suggest that water exercise is a safe alternative exercise modality for individuals with suspected and known hypertension.     

Reasons for risk-reducing mastectomy versus MRI-screening in a cohort of women at high hereditary risk of breast cancer

Objective

To determine the reasons that motivate women in a cohort of women under intensive surveillance for breast cancer to undergo risk-reducing mastectomy (RRM).

Patients and methods

Women with a BRCA1 or BRCA2 mutation who were enrolled in an MRI-based breast screening study were eligible to participate in this survey. A self-administered questionnaire was given to women who did, and who did not terminate annual MRI-based surveillance in order to undergo RRM. The questionnaire included information on family history, risk perception and satisfaction with screening. In addition, women were asked to provide the principal reason for their choice of having preventive surgery or not, and were asked about their satisfaction with this choice.

Results

246 women without breast cancer participated in the study. Of these, 39 women (16%) elected to have RRM at some point after initiating screening. Although women who had a mother or sister with breast cancer were more likely to opt for RRM than were women with no affected first-degree relative (21% versus 10%) this did not reach statistical significance. Women who perceived their breast cancer risk to be greater than 50% were more likely to opt for RRM than were women who estimated their risk to be less than 50% (19% versus 6%). Fear of cancer was the most common reason cited for choosing to have RRM (38% of respondents) followed by having had a previous cancer, (25%), then concern over their children (16%).

Conclusion

Among women with a BRCA mutation who are enrolled in an MRI-based screening program, a high perception of personal breast cancer risk and a history of breast cancer in a first-degree relative are predictors of the decision to have RRM.     

Inhalational anthrax

Inhalational anthrax is a lethal infection acquired from the inhalation of Bacillus anthracis, a pathogen classified as a Category A bioterrorist agent by the Centers for Disease Control and Prevention. The recent 2001 attack in which weaponized spores were delivered by mail to several US cities exposed our vulnerability to bioterrorism, and taught us important lessons in the timely diagnosis of this devastating disease. It is clear that patient mortality is significantly decreased by early recognition and immediate administration of antibiotic therapy. Unfortunately, the nonspecific clinical presentation is often misinterpreted as a flu-like illness and confirmatory microbiologic tests may take up to 24 hours. Radiologic manifestations, however, are distinctive and may prove essential in directing appropriate clinical care in the critical early hours of inhalational anthrax.     

Targeting chemokine receptors in chronic inflammatory diseases: an extensive review

The traffic of the different types of immune cells is an important aspect in the immune response. Chemokines are soluble peptides that are able to attract cells by interaction with chemokine receptors on their target cells. Several different chemokines and receptors exist enabling the specific trafficking of different immune cells. In chronic inflammatory disorders there is abundance of immune cells present at the inflammatory site. This review focuses on the role of chemokine receptors in chronic inflammatory disorders of the lungs, intestine, joints, skin and nervous system and the potential of targeting these receptors as therapeutic intervention in these disorders.     

Soluble Urokinase Plasminogen Activator Receptor (suPAR) is Associated with Metabolic Changes in HIV-1-Infected Africans: A Prospective Study

Soluble urokinase plasminogen activator receptor (suPAR) is associated with inflammation and may predict lipodystrophy and dysmetabolism in human immunodeficiency virus (HIV)-infected individuals on antiretroviral therapy. We aimed to assess firstly, whether suPAR levels are elevated in treated and untreated HIV-1-infected Africans compared to uninfected controls at baseline and at a 3-year follow-up, and secondly whether suPAR levels are correlated with cardiovascular and/or metabolic changes. SuPAR, cardiovascular, and metabolic variables were assessed and the percentage change was determined. HIV-1-infected black South Africans had significantly higher suPAR levels than uninfected controls at baseline and at follow-up 3 years later. However, only the treated HIV-1-infected participants showed an increase in suPAR levels at follow-up. The treated group also showed signs of lipodystrophy and their baseline suPAR levels correlated positively with an increased waist circumference. This study indicates that suPAR levels increase and that baseline suPAR is associated with an increase in abdominal fat distribution in HIV-infected black Africans on antiretroviral therapy.