Intravital imaging of the kidney using multiparameter multiphoton microscopy

Intravital optical microscopy provides a powerful means of studying the cell biology in the most physiologically relevant setting. The ability of multiphoton microscopy to collect optical sections deep into biological tissues has opened up the field of intravital microscopy to high-resolution studies of multiple organs. Presented here are examples of how two-photon microscopy can be applied to intravital studies of kidney physiology and the study of disease processes. These include studies of cell vitality and apoptosis, fluid transport, receptor-mediated endocytosis, blood flow, and leukocyte trafficking. Efficient two-photon excitation of multiple fluorophores permits comparison of multiple probes and simultaneous characterization of multiple parameters. Two-photon microscopy can now provide a level of investigation previously unattainable in intravital microscopy, enabling kinetic analyses and physiological studies of the organs of living animals with subcellular resolution. Therefore, application of this technology will provide direct visualization of organ-specific and cell-specific responses to an array of stimuli and therapeutic approaches, enhancing our understanding and treatment of disease processes.     

Sildenafil increases ocular perfusion

Purpose: Our goal was to determine whether visual system responses to sildenafil accompany shifts in ocular perfusion.The human choroid, which supports the metabolic functionof the outer retina, is an erectile tissue, analogous in many respects to the corpus cavenosum. Methods: Right eyes of 12 normal adults were evaluated before and 2 hafter 50 mg oral dose of sildenafil. Pulsatile ocular blood flow (POBF), intraocular pressure (IOP), Heidelberg retinal flowmetry (HRT), 4.26 cpd, 7.5 Hz temporally-modulated contrast sensitivity (CS), full-threshold C-20 frequency doubling technology (FDT) perimetry, and blood pressure (BP) were measured.Results: POBF (+29.4%; p > 0.016) and CS (+33.6%; p > 0.014%)increased within 110 (±7.7) minutes after sildenafil administration. No subject demonstrated decreases in either variable. HRF flow values increase among 7 of the 9 eyes producing stable scans (+8.2%; p > 0.1). FDT values did not change significantly, nor did systemic pulse amplitude or mean IOP.Conclusions: Since IOP and systemic pulse amplitude bothremained stable after sildenafil administration, while POBF values increased to a level nearly one third greater than baseline. It appears sildenafil can induce intrinsic change in the choroidal vasculature, with an apparently positive impact on pericentral contrast sensitivity. This effect may be of clinical utility.     

Imagery rehearsal therapy for chronic nightmares in sexual assault survivors with posttraumatic stress disorder: a randomized controlled trial

CONTEXT: Chronic nightmares occur frequently in patients with posttraumatic stress disorder (PTSD) but are not usually a primary target of treatment. OBJECTIVE: To determine if treating chronic nightmares with imagery rehearsal therapy (IRT) reduces the frequency of disturbing dreams, improves sleep quality, and decreases PTSD symptom severity. DESIGN, SETTING, AND PARTICIPANTS: Randomized controlled trial conducted from 1995 to 1999 among 168 women in New Mexico; 95% had moderate-to-severe PTSD, 97% had experienced rape or other sexual assault, 77% reported life-threatening sexual assault, and 58% reported repeated exposure to sexual abuse in childhood or adolescence. INTERVENTION: Participants were randomized to receive treatment (n = 88) or to the wait-list control group (n = 80). The treatment group received IRT in 3 sessions; controls received no additional intervention, but continued any ongoing treatment. MAIN OUTCOME MEASURES: Scores on the Nightmare Frequency Questionnaire (NFQ), Pittsburgh Sleep Quality Index (PSQI), PTSD Symptom Scale (PSS), and Clinician-Administered PTSD Scale (CAPS) at 3- and 6-month follow-up. RESULTS: A total of 114 participants completed follow-up at 3 and/or 6 months. Comparing baseline to follow-up (n = 97-114), treatment significantly reduced nights per week with nightmares (Cohen d = 1.24; P<.001) and number of nightmares per week (Cohen d = 0.85; P<.001) on the NFQ and improved sleep (on the PSQI, Cohen d = 0.67; P<.001) and PTSD symptoms (on the PSS, Cohen d = 1.00; P<.001 and on the CAPS, Cohen d = 1.53; P<.001). Control participants showed small, nonsignificant improvements for the same measures (mean Cohen d = 0.21). In a 3-point analysis (n = 66-77), improvements occurred in the treatment group at 3-month follow-up (treatment vs control group, Cohen d = 1.15 vs 0.07 for nights per week with nightmares; 0.95 vs -0.06 for nightmares per week; 0.77 vs 0.31 on the PSQI, and 1.06 vs 0.31 on the PSS) and were sustained without further intervention or contact between 3 and 6 months. An intent-to-treat analysis (n = 168) confirmed significant differences between treatment and control groups for nightmares, sleep, and PTSD (all P<.02) with moderate effect sizes for treatment (mean Cohen d = 0.60) and small effect sizes for controls (mean Cohen d = 0.14). Posttraumatic stress symptoms decreased by at least 1 level of clinical severity in 65% of the treatment group compared with symptoms worsening or not changing in 69% of controls (chi(2)(1) = 12.80; P<.001). CONCLUSIONS: Imagery rehearsal therapy is a brief, well-tolerated treatment that appears to decrease chronic nightmares, improve sleep quality, and decrease PTSD symptom severity.     

Follow-up of a case of retroperitoneal fibroses treated sequencially via right side autotransplant and left uterolysis with wrapper of posterior preperitoneal fat

We present a case of retroperitoneal fibrosis treated with a renal autotransplantation in a patient inicially treated with endourologic measures and corticotherapy without success. The extense ureteral affectation was the indication to carry out an autotransplant. The follow-up is of nine years, with the function of the renal unity still preserved. We checked the literature for the therapeutic possibilities, medical as much as surgical, of the retroperitoneal fibrosis with special attention to the usage of the refractory IRF to other treatments. This revised version was published online in June 2006 with corrections to the Cover Date.     

Endotoxin shock in the beagle dog.

The hemodynamic and metabolic responses to endotoxemia were assessed in seven splenectomized, chronically instrumented, conscious but lightly sedated beagle dogs. Measurements included: cardiac output (CO), right and left atrial pressures (RAP, LAP), systemic and pulmonary arterial pressures (SAP, PAP), and heart rate (HR). Arterial blood samples were measured for blood gas tensions, pH, lactate, and pyruvate. After a brief control period, 1 mg/kg endotoxin (Difco 026:B6) was given as an intravenous bolus. Two hours later, each animal was treated with low-molecular weight dextran (LMDX), 2 ml/kg/min for 15 minutes. Endotoxin initially produced a precipitate decline in CO, HR, RAP, LAP, and SAP with concurrent pulmonary hypertension; both pulmonary and systemic vascular resistance increased significantly, then declined to control values as the animal partially recovered. A progressive metabolic acidosis with excess lactate accumulation developed. LMDX produced a significant increase in CO, SAP, PAP, and LAP with a decrease in HR; RAP increased slightly. With hydration, hemodilution was noted along with relief of the metabolic acidosis and the oxygen debt. We conclude (1) neither pulmonary nor systemic vasconstriction persisted in the shocked dog, (2) the response of the pulmonary and systemic vascular beds to endotoxin was qualitatively similar, and (3) oncotic fluid therapy appeared to restore the hemodynamic and metabolic parameters to preshock values.     

Hepatic basolateral plasma high-affinity Ca2+-ATPase is inhibited by nitric oxide and peroxynitrite anion

The aim of the present work was to study the effect of nitric oxide (NO) and peroxynitrite radicals on basolateral liver plasma membrane activity of high-affinity Ca2+-ATPase. Basolateral membranes were isolated by ultracentrifugation in sucrose gradients and characterized enzymatically. Basolateral membranes were incubated with S-nitroso-N-acetyl-penicillamine (SNAP, an NO donor) or 3-morpholinosydnonimine (SIN-1, a peroxynitrite donor). The liberation of NO or peroxynitrite was monitored by measuring in the medium. Calcium ATPase activity decreased by NO and peroxynitrite in a concentration-dependent manner. It is likely that both compounds inhibit ATPase activity by oxidation of thiol groups of the enzyme. Our results suggest that NO may exert part of its cytotoxic properties by inhibiting the calcium ATPase activity. Inhibition of calcium ATPase may result in Ca2+ accumulation, which in turn may be useful as an intracellular signal.     

Laparoscopic splenectomy in pediatric patients with hematologic diseases.

OBJECTIVE: The aim of this study was to evaluate our experience with laparoscopic splenectomy in pediatric patients with hematologic diseases. METHODS: A retrospective chart review was performed to analyze the following: indication for splenectomy, pre- and peri-operative management, surgical technique, complications, duration of hospitalization, and outcome. RESULTS: Eleven patients underwent laparoscopic splenectomy for the following indications: recurrent thrombocytopenia (<10,000) in seven with chronic immune thrombocytopenic purpura; anemia in two with hereditary spherocytosis; and hypersplenism in one and recurrent splenic sequestration in another with homozygous hemoglobin S. The six girls and five boys had a median age of 7 years. The median operative time was 180 minutes, and the median hospitalization was 72 hours. Among the patients with immune thrombocytopenic purpura (median platelet count, 153,000), those patients (n=3) with platelet counts of <100,000 did not suffer any bleeding complications. The patient with hypersplenism and homozygous hemoglobin S required a small incision in the left lower quadrant to facilitate removal of a 558-gram spleen. This patient also underwent cholecystectomy for cholelithiasis. The operative time was 295 minutes, and he was hospitalized for 5 days because of atelectasis. CONCLUSIONS: Laparoscopic splenectomy is a safe and effective procedure in children with hematological disorders.