Alteration in ouabain-sensitive sodium potassium pump of erythrocytes during pregnancy induced hypertension: a kinetic study

The erythrocytes are widely used as model cells for studies of sodium-potassium pump (Na(+)-K(+) pump) in health and disease. Hence, to explore the possible role of the Na(+) transport across the cell membrane in the pathogenesis of pregnancy-induced hypertension (PIH), the present study was conducted to assess the Na(+)-K(+) pump functions in relation to its intrinsic kinetic properties using erythrocytes (RBC). Erythrocyte sodium concentration in pregnancy-induced hypertensive women was significantly (p<0.01) lower in comparison to normotensive pregnant women. On the contrary erythrocyte potassium was significantly higher (p<0.01) in PIH women as compared to normotensive pregnant women. Observed alterations in Na(+) and K(+) concentrations in erythrocytes were associated with significantly (p<001) increased Ouabain-sensitive sodium efflux rate and rate constants in erythrocytes from PIH women. Further, kinetic studies revealed that increased Ouabain-sensitive efflux rate constant in RBC from PIH women was accompanied by increased maximal velocity (V(max)) of Na(+)-K(+) pump. However, the affinity constant (K(m)) was unaltered in both the groups. Therefore, these findings suggest that increased Na(+)-K(+) pump activity in RBC of PIH women could be due to either increased numbers of Na(+)-K(+) pump units of increased numbers of active subunits of Na(+)-K(+) pump possibly due to specific plasma factors in PIH women.

Postcoital vaginal laceration in a patient presenting with signs of small bowel perforation: report of a case

Postcoital vaginal rupture or tear is a well-known entity to the gynecologist, albeit unusual; however, such cases are rarely encountered by the general surgeon. The index case is reported to highlight the rare situation wherein a middle-aged woman underwent laparotomy for a suspected small bowel perforation, which revealed a vaginal tear as the cause of pneumoperitoneum. This case emphasizes the importance of taking a gynecological history and performing a gynecological examination when the clinical diagnosis is uncertain.

Assessment of near-infrared spectral information for rapid monitoring of bioprocess quality

Access to real-time process information is desirable for consistent and efficient operation of bioprocesses. Near-infrared spectroscopy (NIRS) is known to have potential for providing real-time information on the quantitative levels of important bioprocess variables. However, given the fact that a typical NIR spectrum encompasses information regarding almost all the constituents of the sample matrix, there are few case studies that have investigated the spectral details for applications in bioprocess quality assessment or qualitative bioprocess monitoring. Such information would be invaluable in providing operator-level assistance on the progress of a bioprocess in industrial-scale productions. We investigated this aspect and report the results of our investigation. Near-infrared spectral information derived from scanning unprocessed culture fluid (broth) samples from a complex antibiotic production process was assessed for a data set that incorporated bioprocess variations. Principal component analysis was applied to the spectral data and the loadings and scores of the principal components studied. Changes in the spectral information that corresponded to variations in the bioprocess could be deciphered. Despite the complexity of the matrix, near-infrared spectra of the culture broth are shown to have valuable information that can be deconvoluted with the help of factor analysis techniques such as principal component analysis (PCA). Although complex to interpret, the loadings and score plots are shown to offer potential in process diagnosis that could be of value in the rapid assessment of process quality, and in data assessment prior to quantitative model development.

Local control of neurofilament accumulation during radial growth of myelinating axons in vivo. Selective role of site-specific phosphorylation

The accumulation of neurofilaments required for postnatal radial growth of myelinated axons is controlled regionally along axons by oligodendroglia. Developmentally regulated processes previously suspected of modulating neurofilament number, including heavy neurofilament subunit (NFH) expression, attainment of mature neurofilament subunit stoichiometry, and expansion of interneurofilament spacing cannot be primary determinants of regional accumulation as we show each of these factors precede accumulation by days or weeks. Rather, we find that regional neurofilament accumulation is selectively associated with phosphorylation of a subset of Lys-Ser-Pro (KSP) motifs on heavy neurofilament subunits and medium-size neurofilament subunits (NFMs), rising >50-fold selectively in the expanding portions of optic axons. In mice deleted in NFH, substantial preservation of regional neurofilament accumulation was accompanied by increased levels of the same phosphorylated KSP epitope on NFM. Interruption of oligodendroglial signaling to axons in Shiverer mutant mice, which selectively inhibited this site-specific phosphorylation, reduced regional neurofilament accumulation without affecting other neurofilament properties or aspects of NFH phosphorylation. We conclude that phosphorylation of a specific KSP motif triggered by glia is a key aspect of the regulation of neurofilament number in axons during axonal radial growth.

At-line monitoring of a submerged filamentous bacterial cultivation using near-infrared spectroscopy

The use of near infra-red spectroscopy (NIRS) to monitor a submerged filamentous bacterial bioprocess was investigated. An industrial strain of the filamentous bacterium Streptomyces fradiae was cultured in a 12 litre stirred tank reactor (STR) using a complex medium. This mycelial 4 phase (oil, water, gas and solid) system produced highly complex and variable matrices, therefore monitoring such a complex fluid with NIRS represented a considerable challenge. Nevertheless, successful models for four key analytes (methyl oleate, glucose, glutamate and ammonium) were built at-line (rapid off-line) using NIRS. In the present study, the methods used to formulate, select and validate the models for the key analytes are discussed, with particular emphasis on how the model performance can be critically evaluated. Since previous reports on NIRS in monitoring bioprocesses have either involved simpler matrices, or, in filamentous systems, have not discussed how NIRS models can be critically assessed, the emphasis in the present study on providing an insight into the modelling process in such a complex matrix, may be particularly important to the applicability of NIRS to such industrial bioprocesses.

Critical evaluation of models developed for monitoring an industrial submerged bioprocess for antibiotic production using near-infrared spectroscopy

Near-infrared spectroscopy (NIRS) is known to have potential for cost-effective monitoring of bioprocesses. Although this has been demonstrated in many instances and several models have been reported, information regarding the complexity of models required and their utility over extended periods of time is lacking. In the present study, the complexity of the models required for the NIRS prediction of substrate (oil) and product (tylosin) concentration in an industrial bioprocess that employs a physicochemically heterogeneous medium for antibiotic production was assessed. Measurements made by both the diffuse reflectance and transmittance modes were investigated. SEP values for the prediction of the analytes averaged 5% or less, for the successful models, when evaluated using an external validation set, 2 years after the initial model development exercise. Diffuse reflectance measurements showed poorer results, compared to transmittance measurements, especially for monitoring tylosin. In general, this investigation provides evidence to support the fact that models built for the prediction of analytes in a commercial bioprocess that employs a physicochemically complex production medium can be robust in performance over an extended period of time and that simple models based on fewer terms or latent variables can perform well, even in the context of matrices that are relatively complex. It also indicates that sample presentation is likely to be a critical factor in the successful application of NIRS in bioprocess monitoring, which merits further detailed investigation.

Dental floss ingestion requiring endoscopic retrieval

We report an unusual case of a toddler who ingested dental floss and who subsequently was intubated in a community ED prior to transfer to our pediatric tertiary care center for endoscopic removal of the foreign body.

Inflammatory bowel disease in children and young adults: correlation of sonographic and clinical parameters during treatment

OBJECTIVE

The objective of this study was to evaluate the sonographic findings of inflammatory bowel disease activity in children undergoing treatment.

SUBJECTS AND METHODS

Eighty-eight sonograms were obtained of 23 bowel segments in 17 children and young adults (age range, 10-21 years; mean, 16 years) with new or recurrent inflammatory bowel disease. Sixteen segments were involved with Crohn's disease and seven with ulcerative colitis. Serial sonography (range, two to eight examinations; mean, four per segment) was performed while patients underwent treatment. Bowel wall thickness measurements and color and power Doppler sonography grading were recorded and compared with clinical data.

RESULTS

All 17 patients had at least one abnormal bowel segment on initial sonography. The correlation was significant (p < 0.01). Agreement was 91% on direction of change over time between bowel wall thickness and Doppler grades, with 100% correlation between color and power Doppler sonography grades. In patients with Crohn's disease, the correlation was significant (p < 0.05) between bowel wall thickness and Doppler grades with two of seven and four of seven clinical parameters, respectively. In patients with ulcerative colitis, the correlation was significant (p < 0.05) between bowel wall thickness and Doppler sonography grades with four of seven and three of seven clinical parameters, respectively. The erythrocyte sedimentation rate correlated with all sonographic measurements in both patient groups. Combining bowel wall thickness and Doppler sonography, the percentage of agreement was significant in the direction of change, with five of seven clinical parameters in both patient groups.

CONCLUSION

Gray-scale and color or power Doppler sonography can show changes in disease activity in children and young adults undergoing treatment for inflammatory bowel disease.

Issues in the development of an industrial bioprocess advisory system

The background and motivation for the construction of a fault detection and advisory system for an industrial fermentation process plant are described. Here, the knowledge extracted from the operators (implemented in the form of production rules) is integrated with multivariate data-based methods for fault detection. The industrial benefits arising from this integrated system include: (1) reduced variability, (2) increased mean performance levels, (3) reduced operator-training time and (4) knowledge management in the broader organization.

The role of intraoperative heparin in cyclosporine treated cadaveric renal transplant recipients

PURPOSE

We analyze the effect of intraoperative heparin in cadaveric renal transplantation.

MATERIALS AND METHODS

We examined the records of 100 consecutive cadaveric transplant recipients who received 5,000 units of heparin at the time of vascular clamping (group 1), and compared the incidence of graft thrombosis and postoperative hemorrhagic complications to 100 consecutive cadaveric transplant recipients who did not receive heparin (group 2). The groups were similar in terms of donor age, sex, number of transplant recipients, sensitization, multiple vessels, delayed graft function and human leukocyte antigen mismatch. All patients received cyclosporine based triple therapy immunosuppression. All explanted grafts were examined histologically to rule out hyperacute rejection.

RESULTS

There was no statistical difference between the 2 groups. The overall incidence of graft thrombosis was 5% (6% in group 1 and 4% in group 2). There was a greater need for blood transfusion in group 1, with 25 patients requiring transfusion postoperatively versus 14 in group 2.

CONCLUSIONS

Intraoperative heparin did not reduce the incidence of graft thrombosis in this retrospective study. It did increase the postoperative blood transfusion requirements. As a result of this analysis, we have abandoned its use.

Lipolysis is an important determinant of isoproterenol-induced myocardial necrosis

The cardiotoxic effect of isoproterenol (ISO) is associated with, and possibly due to, calcium overload. Prior work suggests that calcium entry into cardiac myocytes after ISO administration occurs in two phases: an early rapid phase, followed by a slow phase beginning about 1 hour after ISO injection, leading to a peak myocardial calcium level after about 4 hours. We have tested the relationship of these phases to myocardial necrosis (MN) by determining the time after ISO administration at which the commitment to MN occurs. This was done by administration of propranolol at various times before and after ISO. In addition, since ISO induces lipolysis, and lipids can be toxic, experiments were conducted to determine if adrenergically-activated lipolysis could play a significant role in ISO-MN. We found that propranolol protected the myocardium equally well when administered anytime within 2 hours of ISO injection, but had no effect when given 4 hours after ISO. This showed that metabolic events taking place more than two hours after ISO injection are required for ISO-MN. As expected from prior work, there was a small and consistent amount of propranolol-resistant ISO-MN. Lipolysis, assessed by measuring serum glycerol levels, increased to tenfold above base line at one hour after ISO administration and returned to near basal levels at 4 hours. Potentiation of lipolysis by intravenous injections of phospholipase A2 (PLA2) or lipoprotein lipase (LPL) to rats treated with ISO substantially augmented MN. Propranolol completely blocked the increase in necrosis produced by PLA2 when given with ISO. Lipases induced only minimal necrosis in the absence of ISO. Administration of adenosine (an anti-lipolytic agent), oxfenicine (an inhibitor of mitochondrial palmitoyl carnitine transferase), or vitamin C (an anti-oxidant) resulted in a 55-60% reduction in MN. These results suggest that critical necrosis-determining events occur between 2 and 4 hours after ISO administration and imply a relationship between ISO-induced lipolysis, calcium influx, and ISO-MN. We hypothesize that importance of lipolysis as a determinant of ISO-MN is related to the generation of free fatty acids, their oxidized/metabolic products, or direct damage to plasma membrane.

Pathways from war trauma to posttraumatic stress symptoms among Tamil asylum seekers, refugees, and immigrants

Path analysis was used to examine the antecedents of posttraumatic stress (PTS) symptoms in Tamil asylum-seekers, refugees, and immigrants in Australia. The Harvard Trauma Questionnaire and a postmigration living difficulties questionnaire were completed by 62 asylum-seekers, 30 refugees, and 104 immigrants who responded to a mail-out. Demographic characteristics, residency status, and measures of trauma and postmigration stress were fitted to a structural model in PTS symptoms. Premigration trauma exposure accounted for 20% of the variance of PTS symptoms. Postmigration stress contributed 14% of the variance. Although limited by sampling constraints and retrospective measurement, the study supports the notion that both traumatic and posttraumatic events contribute to the expression of PTS symptoms.

Measles immunisation coverage in urban slums

A cross-sectional, community-based study was conducted in 32 slums of Udaipur city to assess the prevalence of missed opportunities for measles immunization, reason for their occurrence and potential impact of avoiding them on measles immunization coverage. Two hundred and sixty-five children, between the age of 9 and 24 months were enlisted for the study, using a practical cluster sampling method. Immunization status of the children, visits to health facilities after 9 months of age and reasons for non-immunization were noted. Missed opportunities for measles immunization was defined as any visit by an eligible child to a health facility, which did not result in his/her vaccination. Measles immunization coverage amongst the study population was 50.61%. The prevalence of missed opportunities for measles immunization was 14.3%. Not offering measles immunization at curative visits (86.9%) was the major reason for missing opportunities. Avoiding all missed opportunities could have increased the measles immunization coverage to 64.9%.

Synthesis, characterization and antimicrobial studies of metal(II) bis-chelates and mixed-ligand complexes of alpha-(2-hydroxyphenyl)-N-(1-phenyl-2-nitroethyl)nitrone

This paper describes the synthesis of complexes of the type MB2. 2H2O and CuBL.2H2O where BH = alpha-(2-hydroxyphenyl)-N-(1-phenyl-2-nitroethyl)-nitrone, M = copper(II)/cobalt(II)/nickel(II) and LH = salicylaldehyde/salicylaldoxime/8-hydroxyquinoline/2-hydroxypyridine. The magnetic moment, ligand field spectra, thermal and ESR studies reveals that these dihydrates possess octahedral geometry. The antimicrobial studies of these complexes against several microorganisms such as Staphylococcus aureus, Escherichia coli, Klebsiella aerogenes, Salmonella typhi and Pseudomonas sp. have been tested and reported in comparison with ceftazidime standard.

The effects of perhexiline on the rat coronary vasculature

The predominant site and mechanism(s) of perhexiline-induced coronary vasodilatation were investigated in the rat heart. Perhexiline was more potent in the Langendorff perfused heart than in the left anterior descending coronary artery (EC50; 0.27 microM, confidence limits 0.19-0.39: 2.7 microM, 2.0-3.4, respectively). Selective endothelial inactivation with Triton X-100 in the perfused heart, reduced the response to perhexiline 1 microM (76+8% to 30+3% of control). 1H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) 3 microM, Nomega-nitro-L-arginine 100 microM, or a combination of the latter with indomethacin 10 microM, had no significant effect on responses to perhexiline in the perfused heart. Unlike bradykinin-induced vasodilatation, responses to perhexiline were not inhibited by tetrabutylammonium 1 mM, or charybdotoxin 20 nM. SKF525A 5 microM inhibited both perhexiline and bradykinin responses, while apamin 1 microM and glibenclamide 3 microM inhibited neither. Perhexiline exerts partially endothelium-dependent coronary vasodilator effects in the rat, predominantly on small coronary arteries, which appear to be independent of nitric oxide (NO), prostacyclin and the endothelium-derived hyperpolarising factor (EDHF) released by bradykinin.

Caspase-mediated fragmentation of calpain inhibitor protein calpastatin during apoptosis

Two cysteine protease families (caspase and calpain) participate in apoptosis. Here we report that the endogenous calpain inhibitor calpastatin is fragmented by caspase(s) to various extents during early apoptosis in two cell types. In anti-fas or staurosporine-treated Jurkat T-cells, the high-molecular-weight form (HMW) of calpastatin (apparent Mr 110 K) was extensively degraded to immunoreactive fragments of Mr 75 K and 30 K In apoptotic SH-SY5Y human neuroblastoma cells, HMW calpastatin was degraded to a major immunoreactive fragment of 75 K. In both cell types, fragmentation of HMW calpastatin was blocked by a caspase-specific inhibitor carbobenzoxy-Asp-CH2OC(O)-2,6-dichlorobenzene. In vitro translated HMW calpastatin was sensitive to proteolysis by recombinant caspase-1, -3, and -7. By contrast, in vitro translated LMW calpastatin (which lacks domains L and I) was cleaved into multiple fragments only by caspase-1 and was relatively resistant to caspase-3, -7, and other caspases tested. Consistently with that, purified erythroid LMW calpastatin was also highly susceptible to caspase-1 digestion. Recombinant human calpastatin spanning domain I through III (CAST(DI-III)) was found cleaved by caspase-1 at at least three sites, located in either the A or the C helix of domains I and III (ALDD137*L, LSSD203*F and ALAD404*S), while only a single site (ALDD137*L) was cleaved by caspase-3. These findings suggest that both HMW and LMW calpastatins are more vulnerable to caspase-1 than to caspase-3. Surprisingly, both erythroid LMW calpastatin and recombinant CAST(DI-III) fragmented by caspase-1 suffered only a less than twofold reduction of inhibitory activity toward calpain. We propose that the proteolysis of calpastatin in early apoptosis might have yet unidentified effects on the cross-talk between the two protease systems.

Trauma exposure, postmigration stressors, and symptoms of anxiety, depression and post-traumatic stress in Tamil asylum-seekers: comparison with refugees and immigrants

Compared to research on displaced persons whose refugee status has been endorsed prior to arriving in Western countries, there is little systematic information available about levels of past trauma, postmigration living difficulties and psychiatric symptoms amongst asylum-seekers who claim refugee status only after arrival. Asylum-seekers, authorized refugees and immigrants of Tamil background were recruited by personal contact and mail-out in Sydney, Australia. A total of 62 subjects, constituting approximately 60% of the estimated pool of Tamil asylum-seekers, agreed to participate in the study. They returned statistically significantly higher scores than immigrants (n = 104) on measures of past trauma, symptoms of anxiety, depression and post-traumatic stress, and on all dimensions of postmigration difficulties. Asylum-seekers did not differ from refugees (n = 30) on measures of past trauma or psychiatric symptoms, but they scored higher on selective components of postmigration stress relating to difficulties associated with their insecure residency status. Although limited by sampling and diagnostic constraints, the present study suggests that asylum-seekers may be a high-risk group in relation to ongoing stress in the postmigration period.