Interstitial pressure gradients around joints; location of chief resistance to fluid drainage from the rabbit knee. (57/617)

The hypothesis has been advanced that synovium offers the main resistance to fluid escape from joints, even though it is under 20 microm thick. To test this, fluid was infused into the knee joint cavity of anaesthetised rabbits to set up a pressure gradient, then the profile of periarticular interstitial fluid pressure (P(if)) was measured by advancing a micropipette, connected to a servo-null pressure recorder, in steps through a periarticular tissue 'window' until the joint cavity was entered. With intra-articular pressure (P(j)) raised to 15 cmH(2)O (the pressure of an acute joint effusion) the pressure gradient dP(if) /dx (where x is distance) across the synovial lining was 0.47 +/- 0.04 cmH(2)O microm(-1) (n = 10 joints). This was 23.5-fold greater than the gradient in the subsynovium (0.02 +/- 0.01 cmH(2)O microm(-1); P < 0.0001, Student's t test), indicating that the hydraulic resistivity of the subsynovium is 4 % of that of the synovium. The pressure profile was not altered by circulatory arrest. To test the hypothesis further, the effect of a stab perforation of the synovial lining on fluid drainage rate ((.Q(s)) was studied. Perforation raised both.Q(s) and the conductance term d.Q(s)/dP(j) more than 10-fold (n = 6 joints; P < 0.0001, ANOVA). The results thus support the view that, despite its thinness, the synovial lining offers the main hydraulic resistance to fluid drainage from a synovial joint.  (+info)

Serial ultrasonography, hormonal profile and antisperm antibody response after testicular sperm aspiration. (58/617)

BACKGROUND: In many fertility centres, intracytoplasmic sperm injection (ICSI) with epididymal or testicular spermatozoa is a routine treatment for men with azoospermia. In this prospective study, the physiological consequences after testicular sperm aspiration (TESA), using suction and a 19 gauge needle, were evaluated. METHODS AND RESULTS: Thirty-five consecutive men with azoospermia underwent TESA. Testicular ultrasonography with Doppler flow imaging was performed and testicular volumes were evaluated pre-operatively and 3 months after aspiration. If focal testicular lesions were found, further examinations were performed 6 and 9 months after TESA. Serum FSH, testosterone and antisperm antibodies (ASA) were analysed. Focal testicular lesions were seen in four out of 61 testes (6.6%) at the 3 month investigation point. Three lesions were resolved after 6 months and all after 9 months. Testicular echogenicity remained unchanged in 50 cases (82%) 3 months after TESA. Four men (11.4%) reported severe subjective discomfort post-operatively, but only one had a medical consultation where an intratesticular haematoma was diagnosed. There were no significant changes in FSH and testosterone after surgery and testicular volumes were similar after 3 months. There were three borderline cases of ASA in serum, but none was classified as ASA-positive. CONCLUSIONS: The puncture method of testicular sperm aspiration seems to be a safe method for sperm retrieval, with minimal physiological consequences.  (+info)

Relationship between cytokine mRNA expression and organ damage following cecal ligation and puncture. (59/617)

AIM: To investigate the role of cytokine gene expression in organ damage at different tissue sites during sepsis. METHODS: Male NIH mice were subjected to cecal ligation and puncture (CLP) or sham operation (Sham). Pro-inflammatory cytokine (TNFalpha, IL-1beta and IL-6) and anti-inflammatory cytokine (IL-4) gene expression in the liver and lung tissue were assessed by RT-PCR. The permeability of microvascular and water content in the lungs and liver were also examined. RESULTS: Significant increase in TNFalpha, IL-1beta and IL-6 gene expression was observed at 3 and 12 h after CLP both in the liver and lungs (P<0.01).The level of IL-4 gene expression was not changed after CLP in the lungs, but increased at 12 h after CLP(P<0.01) in the liver tissue. Both the liver and lungs showed a significant increase in microcirculatory permeability at 12 h after CLP(P<0.01), and the increase in the lungs was higher than that in the liver. The water mass fractions in the liver (P<0.05) and lungs (P<0.01) were increased after CLP, and the increase in the lungs happened earlier and more severely than that in the liver. CONCLUSION: The inflammatory response in the liver and lungs was different during sepsis. At the early stage of sepsis, pro-inflammatory reaction dominates both in the liver and lungs. But at the later stage of sepsis, induction of compensatory anti-inflammatory response was seen in the liver but not in the lungs. This difference in situ activity may contribute to the different vulnerability of organ damage during sepsis. The strategy of systemic administration of anti-inflammatory drugs to sepsis should be reconsidered.  (+info)

Effect of acute iNOS inhibition on glomerular function in tubulointerstitial nephritis. (60/617)

BACKGROUND: Tubulointerstitial nephritis (TIN) is characterized by progressive inflammatory infiltrate of the renal interstitium, induction of cortical tubular inducible nitric oxide synthase (iNOS) and reductions in glomerular filtration rate (GFR). These studies were designed to examine the changes in glomerular hemodynamics 7 and 21 days after induction of TIN and to evaluate the effect of acute iNOS blockade on glomerular function in the early stages of this model. METHODS: TIN was induced by immunizing Brown Norway rats with renal tubular antigen in complete Freund's adjuvant (RTA/CFA). Control rats were immunized with CFA alone. Micropuncture and morphologic studies were performed 7 and 21 days after immunization. RESULTS: Histology revealed minimal peritubular and interstitial inflammation in the RTA/CFA group one week after immunization while extensive interstitial inflammation with few preserved superficial nephron was observed three weeks after RTA/CFA immunization. Micropuncture studies on day 7 in the RTA/CFA group revealed a significant reduction in single nephron GFR due to a profound reduction in nephron plasma flow and in the ultrafiltration coefficient. Studies performed on day 21 revealed that single nephron GFR (SNGFR), nephron plasma flow (SNPF) and the ultrafiltration coefficient had returned to the normal baseline value despite the severe reduction in GFR. To assess the role of increased nitric oxide production secondary to iNOS induction on the glomerular hemodynamic changes observed in the early stages of the disease, the iNOS blocker (l-N(6)-iminoethyl lysine, L-NIL) was administered IV (1 mg/h) in RTA/CFA rats and CFA rats. L-NIL had no effect in CFA rats but produced significant increases in GFR, SNGFR and SNPF in RTA/CFA rats. CONCLUSIONS: These results demonstrate that TIN is associated with a progressive reduction in GFR, which is likely the result of functional vasoconstriction and decreases in the ultrafiltration coefficient in the early stages of the disease and on a significant reduction in the number of functioning nephron in the later stages. Induction of iNOS with increased NO production actively participates in the functional changes observed in the early stages of the disease most likely by inhibiting normal endothelial NOS activity.  (+info)

Surface contraction waves (SCWs) in the Xenopus egg are required for the localization of the germ plasm and are dependent upon maternal stores of the kinesin-like protein Xklp1. (61/617)

During the first four cell cycles in Xenopus, islands of germ plasm, initially distributed throughout the vegetal half of the egg cortex, move to the vegetal pole of the egg, fusing with each other as they do so, and form four large cytoplasmic masses. These are inherited by the vegetal cells that will enter the germ line. It has previously been shown that germ plasm islands are embedded in a cortical network of microtubules and that the microtubule motor protein Xklp1 is required for their localization to the vegetal pole [Robb, D., Heasman, J., Raats, J., and Wylie, C. (1996). Cell 87, 823-831]. Here, we show that germ plasm islands fail to localize and fuse in Xklp1-depleted eggs due to the abrogation of the global cytoplasmic movements known as surface contraction waves (SCWs). Thus, SCWs are shown to require a microtubule-based transport system for which Xklp1 is absolutely required, and the SCWs themselves represent a cortical transport system in the egg required for the correct distribution of at least one cytoplasmic determinant of future pattern.  (+info)

Effectiveness of mechanical compression devices in attaining hemostasis after femoral sheath removal. (62/617)

BACKGROUND: Cardiac interventions are widely accepted as a practical treatment option for coronary artery disease. However, few changes have occurred in the techniques used for percutaneous arterial cannulation and for attaining hemostasis after cardiac interventions. To date, researchers have focused on techniques to achieve optimal hemostasis at the time of removal of the arterial catheter and to minimize the impact and complications of arterial puncture. OBJECTIVE: To summarize the best available evidence on the effectiveness of mechanical compression devices used to obtain hemostasis following femoral sheath removal after cardiac interventional procedures. METHOD: An attempt was made to detect both published and unpublished reports of research evaluations of mechanical compression techniques used to attain hemostasis after femoral sheath removal. Methodological quality was assessed by using predesigned criteria. Data were extracted from information on randomized controlled trials and were statistically combined in meta-analysis where possible. Evidence was also synthesized by using narrative summaries. RESULTS: Twelve studies met the inclusion criteria; however, only 3 were included in the meta-analysis. The results of meta-analysis indicated that the mechanical compression technique was the most effective for preventing formation of hematomas. The prevalence of bleeding did not differ significantly for different methods of compression. CONCLUSION: A gap exists in the literature on quality randomized controlled trials of various devices used to attain hemostasis after femoral sheath removal.  (+info)

Laparoscopic ovarian diathermy in women with polycystic ovarian syndrome: a retrospective study on the influence of the amount of energy used on the outcome. (63/617)

BACKGROUND: Currently, there is an uncertainty about the optimum number of punctures to be applied at laparoscopic ovarian diathermy (LOD). This retrospective study was undertaken to investigate the dose-response relationship of LOD. METHODS: The hospital records of 161 women with polycystic ovarian syndrome who underwent LOD were reviewed and the clinical data before and after LOD were documented. Subjects were divided into six groups according to the number of punctures made in their ovaries as follows: group 1, two punctures per ovary; group 2, three punctures; group 3, four punctures; group 4, five punctures; group 5, six punctures and group 6, seven to 10 punctures. Contingency table analysis and analysis of variance were used to compare the outcomes of the different groups. RESULTS: The rates of ovulation, conception and restoration of menstrual regularity after LOD were significantly lower in group 1 compared with other groups. There were no significant differences in the success rates between the other groups. CONCLUSION: Two punctures per ovary are associated with poor results. Three punctures per ovary seem to represent the plateau dose. The application of seven or more punctures per ovary may result in excessive destruction to the ovary without any improvement of the results and should therefore be discouraged.  (+info)

Transepidermal water loss does not correlate with skin barrier function in vitro. (64/617)

The purpose of this study was to investigate the relationship between transepidermal water loss and skin permeability to tritiated water (3H2O) and the lipophilic penetrant sulfur mustard in vitro. No correlation was found between basal transepidermal water loss rates and the permeability of human epidermal membranes to 3H2O (p = 0.72) or sulfur mustard (p = 0.74). Similarly, there was no correlation between transepidermal water loss rates and the 3H2O permeability of full-thickness pig skin (p = 0.68). There was no correlation between transepidermal water loss rate and 3H2O permeability following up to 15 tape strips (p = 0.64) or up to four needle-stick punctures (p = 0.13). These data indicate that transepidermal water loss cannot be unconditionally ascribed to be a measure of skin barrier function. It is clear that further work should be conducted to interpret the significance of measuring transepidermal water loss by evaporimetry.  (+info)