Experience in colorectal surgery at a quaternary care hospital in Bogotá, Colombia

INTRODUCTION AND AIMS

Colorectal cancer is among the three most common cancers worldwide. Knowledge and identification of suboptimal outcome-associated factors enable comprehensive patient management. The aim of the present study was to present the results of the surgical management of colorectal cancer at a quaternary care university hospital.

MATERIALS AND METHODS

An observational, analytic, cross-sectional study was conducted. Information was collected on a retrospective cohort of patients diagnosed with colorectal cancer from 2013 to 2017 at the Hospital Universitario Mayor Méderi, Bogotá, Colombia.

RESULTS

Data on 452 patients, within the study period, were collected. A total of 48.5% of the patients were men, the overall complication rate was 24%, the surgical site infection (SSI) rate was 15.38%, anastomotic dehiscence occurred in 4.18% of the patients, bleeding required reoperation in 1.32%, and the intrahospital mortality rate was 7.47%.

CONCLUSION

Colorectal cancer management at a university hospital was as beneficial as that provided by other types of hospitals, showing a direct association with complete R0 dissections; low complication rates, according to international reports; and reduced overall morbidity.

The role of defects in the persistent photoconductivity of BaSnO3thin films

Time-dependent photoconductivity (PC) and PC spectra have been studied in oxygen deficient BaSnO₃thin films grown on different substrates. X-ray spectroscopy measurements show that the films have epitaxially grown on MgO and SrTiO₃substrates. While on MgO the films are nearly unstrained, on SrTiO₃the resulting film is compressive strained in the plane. Electrical conductivity in dark is increased in one order of magnitude for the films on SrTiO₃in comparison to the one on MgO. This leads to an increase of PC in the latter film in at least one order of magnitude. PC spectra show a direct gap with a value ofEG=3.9eV for the film grown on MgO while on SrTiO₃EG=3.36eV. For both type of films, time-dependent PC curves show a persistent behavior after illumination is removed. These curves have been fitted employing an analytical procedure based on the frame of PC as a transmission phenomenon showing the relevant role of donor and acceptor defects as carrier traps and as a source of carriers. This model also suggests that in the BaSnO₃film on SrTiO₃more defects are created probably due to strain. This latter effect can also explain the different transition values obtained for both type of films.

O-077 The chromosomal constitution of embryos developing from 0PN zygotes

Study question

To compare the ploidy status of embryos originated from zygotes with absence of pronuclei (0PN) with those developing from normal two pronuclei (2PN) fertilization.

Summary answer

We did not find significant differences in euploidy rates between blastocysts from 0PN and 2PN zygotes.

What is known already

Information regarding the ploidy number of 0PN zygotes, even when the pronuclei number is assessed by time-lapse microscope coupled incubators, is still insufficient. Because of this, embryos originating from 0PN zygotes are usually discarded or individualized in order not to include them in first transfers. Even more, abnormal fertilization is considered as a proxy of poor embryo quality.

Study design, size, duration

A retrospective observational study from March 2016 and December 2021 including 80 PGT-A cycles in which at least one of the blastocysts studied developed from oocytes in which pronuclei were not seen at the time of fertilization check.

Participants/materials, setting, methods

307 blastocysts were studied, of which 115 originated from 0PN and 192 from 2PN zygotes. Pronuclear number was assessed 16-20 h after insemination. Zygotes with 0PN were cultured separately from 2PN ones of the same cohort. After extended culture, a biopsy was performed and the material obtained was genetically studied using Next Generation Sequencing. Statistical comparisons were made with Fisher's exact and Chi-square tests. Significance level was set at P<0.05.

Main results and the role of chance

No differences were observed in euploidy rates between the 2PN and 0PN groups [55.2% (106/193) VS 43.5% (50/115)]. In aneuploid embryos originating from 2PN zygotes, a similar amount of trisomies and monosomies was observed (56 and 56 respectively). In contrast, aneuploid embryos from 0PN oocytes showed a greater number of trisomies than monosomies (55 and 35 respectively, P < 0.05). None of the blastocysts resulting from 0PN was haploid, that is, we did not find parthenogenic embryos. Blastocysts derived from 0PN zygotes showed similar quality scoring than those from 2PN ones. To date, 20 euploid blastocysts from the 0PN group have been transferred, producing 12 pregnancies: 6 still ongoing and 4 healthy live births.

Limitations, reasons for caution

Non-visualization of pronuclei in oocytes that later generate normal diploid blastocysts may be due to a faster or slower cell cycle progression. Modifications in the daily fertilization check schedules of busy laboratories should also be considered.

Wider implications of the findings

Contrary to expectations, aneuploid embryos from 0PN oocytes showed a greater number of trisomies than monosomies. A significant fraction of the embryos generated from 0PN zygotes were actually diploid, with similar quality and outcome results than 2PN ones. This makes them perfectly usable in IVF routines.

Trial registration number

Not applicable

P-223 Women aged 40 or older and non-male factor have the same reproductive outcome using intracytoplasmic sperm injection (ICSI) or conventional in vitro fertilization (cIVF)

Study question

Do women aged 40 or older have the same reproductive outcome using ICSI or cIVF when male factor infertility is not present?

Summary answer

Women aged 40 or older with non-male factor partners achieved similar reproductive outcomes either with ICSI or cIVF.

What is known already

Although initially proposed to treat couples with severe male factor infertility, ICSI has become the preferred tool to treat patient populations others than initially intended. Many studies and international forums, however, have alerted that its overuse is not free due to its safety, cost and time-consuming concerns. Moreover, it was noted that it does not increase clinical outcomes even in cases of compromised oocyte factor such as poor responder patients or few oocytes retrieved. However, there is still no information regarding its use in the group of patients of advanced reproductive age.

Study design, size, duration

Retrospective cohort study including 412 women aged 40 or older with non-male factor infertility performing ICSI or cIVF between May 2015 and October 2017.

Participants/materials, setting, methods

Patients underwent ICSI (n = 109) or cIVF (n = 303) according to medical indication. The decision to use ICSI in non-male factor patients was merely operational, with the objective of evaluating oocyte maturity.Those cycles with own oocytes, non-male factor and fresh embryo transfers were included. Semen samples were considered normal following the World Health Organization fifth edition sperm parameters values, and prepared by density gradient selection.

Main results and the role of chance

The primary outcome was clinical pregnancy rate. Secondary outcomes included ongoing pregnancy, miscarriage and implantation rates. Statistical significance was denoted by P < 0.05. The mean age of the women were 41.4 in the ICSI group and 41.6 years in the cIVF group, while the mean age for male couple was 43.6 and 41.6 respectively.

No differences between ICSI and cIVF groups were observed regarding clinical pregnancy [16.5% (18/109) vs. 20.8% (63/303)], ongoing pregnancy [9.2% (10/109) vs. 7.9% (24/303)], miscarriage [41.2% (7/17) vs. 46,5% (20/43)], and implantation rates [11.3% (17/151) vs. 9.9% (50/506)].

Limitations, reasons for caution

These results need confirmation with a bigger population size. As with any retrospective study, the potential for residual confounding exists.

Wider implications of the findings

These data suggest that ICSI offers no clinical benefit for women aged 40 and older with non-male factor infertility, beyond oocyte maturation classification.

Trial registration number

not applicable

Morphine exposure alters Fos expression in a sex-, age-, and brain region-specific manner during adolescence

Data in both humans and preclinical animal models clearly indicate drug exposure during adolescence, when the "reward" circuitry of the brain develops, increases the risk of substance use and other mental health disorders later in life. Human data indicate that different neural and behavioral sequelae can be observed in early versus late adolescence. However, most studies with rodent models examine a single adolescent age compared to a mature adult age, and often only in males. Herein, we sought to determine whether the acute response to the opioid morphine would also differ across adolescence, and by sex. By quantifying Fos positive cells, a proxy for neural activity, at different stages during adolescence (pre-, early, mid-, and late adolescence) and in multiple reward regions (prefrontal cortex, nucleus accumbens, caudate/putamen), we determined that the neural response to acute morphine is highly dependent on adolescent age, sex, and brain region. These data suggest that heterogeneity in the consequences of adolescent opioid exposure may be due to age- and sex-specific developmental profiles in individual reward processing regions. In future studies, it will be important to add age within adolescence as an independent variable for a holistic view of healthy or abnormal reward-related neural development.

A semi-automated brain atlas-based analysis pipeline for c-Fos immunohistochemical data

BACKGROUND

The use of immunohistochemistry to quantify neural markers in various brain regions is a staple of neuroscience research. Numerous programs exist to automate quantification, but manual assignment of regions of interest (ROIs) within individual brain sections remains time consuming and can introduce interobserver variability.

NEW METHOD

We have developed a novel open source FIJI-based immunohistochemical data analysis pipeline, Atlas-Based Analysis (ABA). ABA uses landmark-based image warping to adjust the experimental image to closely align with a published rat brain atlas. c-Fos positive cells are then quantified within predetermined ROI coordinates derived from the brain atlas. Image warping adjusts for natural variation in brain sections to ensure reliable alignment of ROIs for data analysis. This pipeline can be adapted for new atlases, landmarks, ROIs, and quantification measurements.

RESULTS

ABA permits rapid quantification of immunoreactivity in multiple ROIs and produces results with high levels of interobserver consistency.

COMPARISON WITH EXISTING METHODS

Compared to manual ROI designation, ABA reduces total analysis time by ∼70%. With correct use of landmarks for image warping, ABA produces similar results to manually drawn ROIs, results in no interobserver variability, and maintains c-Fos+ pixel dimensions.

CONCLUSIONS

ABA reduces time to obtain reliable results when performing automated immunoreactivity quantification and allows multiple users to analyze data without compromising the reliability of data obtained.

Marijuana use and outcomes in adult and pediatric trauma patients after legalization in California

BACKGROUND

Marijuana has become legal in eight states since 2012. We hypothesized the incidence of marijuana-positive trauma patients and rate of mortality has increased post-legalization.

METHODS

A single level-I trauma center was used to identify patients screening positive for marijuana on urine-toxicology. Patients in the pre-legalization and post-legalization periods were compared.

RESULTS

In the pre-legalization cohort 9.4% were marijuana-positive versus 11.0% in the post-legalization cohort (p = 0.001). Marijuana-positive patients post-legalization had higher rates of critical trauma activation (20.0% vs. 15.0%, p = 0.01) and mortality (2.6% vs. 1.2%, p = 0.03). In the pediatric (age 12-17) subgroup, the incidence of marijuana-positive patients did not change after legalization (pre: 39.3%, post: 46.4%, p = 0.24).

CONCLUSION

The incidence of marijuana-positive trauma patients increased post-legalization. Adult marijuana-positive trauma patients post-legalization were more likely to meet criteria for critical trauma activation and have a higher mortality rate. A subgroup of pediatric patients had an alarmingly high rate of marijuana use.

SUMMARY

The rate of marijuana use among trauma patients increased post-legalization in California. The rate of critical trauma activation also increased as well as the mortality rate.

Mental health in the Americas: an overview of the treatment gap

Objective

To understand the mental health treatment gap in the Region of the Americas by examining the prevalence of mental health disorders, use of mental health services, and the global burden of disease.

Methods

Data from community-based surveys of mental disorders in Argentina, Brazil, Canada, Chile, Colombia, Guatemala, Mexico, Peru, and the United States were utilized. The World Mental Health Survey published data were used to estimate the treatment gap. For Canada, Chile, and Guatemala, the treatment gap was calculated from data files. The mean, median, and weighted treatment gap, and the 12-month prevalence by severity and category of mental disorder were estimated for the general adult, child-adolescent, and indigenous populations. Disability-adjusted Life Years and Years Lived with Disability were calculated from the Global Burden of Disease study.

Results

Mental and substance use disorders accounted for 10.5% of the global burden of disease in the Americas. The 12-month prevalence rate of severe mental disorders ranged from 2% - 10% across studies. The weighted mean treatment gap in the Americas for moderate to severe disorders was 65.7%; North America, 53.2%; Latin America, 74.7%; Mesoamerica, 78.7%; and South America, 73.1%. The treatment gap for severe mental disorders in children and adolescents was over 50%. One-third of the indigenous population in the United States and 80% in Latin America had not received treatment.

Conclusion

The treatment gap for mental health remains a public health concern. A high proportion of adults, children, and indigenous individuals with serious mental illness remains untreated. The result is an elevated prevalence of mental disorders and global burden of disease.

Community Partnering for Behavioral Health Equity: Public Agency and Community Leaders' Views of its Promise and Challenge

Objective

To understand potential for multi-sector partnerships among community-based organizations and publicly funded health systems to implement health improvement strategies that advance health equity.

Design

Key stakeholder interviewing during HNI planning and early implementation to elicit perceptions of multi-sector partnerships and innovations required for partnerships to achieve system transformation and health equity.

Setting

In 2014, the Los Angeles County (LAC) Board of Supervisors approved the Health Neighborhood Initiative (HNI) that aims to: 1) improve coordination of health services for behavioral health clients across safety-net providers within neighborhoods; and 2) address social determinants of health through community-driven, public agency sponsored partnerships with community-based organizations.

Participants

Twenty-five semi-structured interviews with 49 leaders from LAC health systems, community-based organizations; and payers.

Results

Leaders perceived partnerships within and beyond health systems as transformative in their potential to: improve access, value, and efficiency; align priorities of safety-net systems and communities; and harness the power of communities to impact health. Leaders identified trust as critical to success in partnerships but named lack of time for relationship-building, limitations in service capacity, and questions about sustainability as barriers to trust-building. Leaders described the need for procedural innovations within health systems that would support equitable partnerships including innovations that would increase transparency and normalize information exchange, share agenda-setting and decision-making power with partners, and institutionalize partnering through training and accountability.

Conclusions

Leaders described improving procedural justice in public agencies' relationships with communities as key to effective partnering for health equity.

Stakeholder Perspectives on the Social Determinants of Mental Health in Community Coalitions

Objective

Although evidence supports the potential for community coalitions to positively address social determinants of mental health, little is known about the views of stakeholders involved in such efforts. This study sought to understand county leaders' perspectives about social determinants related to the Health Neighborhood Initiative (HNI), a new county effort to support community coalitions.

Design

Descriptive, qualitative study, 2014.

Setting

Community coalitions, located in a large urban city, across eight service planning areas, that serve under-resourced, ethnic minority populations.

Procedures

We conducted key informant interviews with 49 health care and community leaders to understand their perspectives about the HNI. As part of a larger project, this study focused on leaders' views about social determinants of health related to the HNI. All interviews were audio-recorded and transcribed. An inductive approach to coding was used, with text segments grouped by social determinant categories.

Results

County leaders described multiple social determinants of mental health that were relevant to the HNI community coalitions: housing and safety, community violence, and employment and education. Leaders discussed how social determinants were interconnected with each other and the need for efforts to address multiple social determinants simultaneously to effectively improve mental health.

Conclusions

Community coalitions have an opportunity to address multiple social determinants of health to meet social and mental health needs of low-resourced communities. Future research should examine how community coalitions, like those in the HNI, can actively engage with community members to identify needs and then deliver evidence-based care.

A Window of Opportunity: Visions and Strategies for Behavioral Health Policy Innovation

Objective

The New York City's Thrive (ThriveNYC) and the Los Angeles County Health Neighborhood Initiative (HNI) are two local policies focused on addressing the social determinants of behavioral health as a preventive strategy for improving health service delivery. On January 29, 2016, leaders from both initiatives came together with a range of federal agencies in health care, public health, and policy research at the RAND Corporation in Arlington, Virginia. The goal of this advisory meeting was to share lessons learned, consider research and evaluation strategies, and create a dialogue between stakeholders and federal funders - all with the purpose to build momentum for policy innovation in behavioral health equity.

Methods

This article analyzes ethnographic notes taken during the meeting and in-depth interviews of 14 meeting participants through Kingdon's multiple streams theory of policy change.

Results

Results demonstrated that stakeholders shared a vision for behavioral health policy innovation focused on community engagement and social determinants of health. In addition, Kingdon's model highlighted that the problem, policy and politics streams needed to form a window of opportunity for policy change were coupled, enabling the possibility for behavioral health policy innovation.

Conclusions

The advisory meeting suggested that local policy makers, academics, and community members, together with federal agents, are working to implement behavioral health policy innovation.

Estimation of central aortic forces in the ballistocardiogram under rest and exercise conditions

The ballistocardiogram (BCG) signal represents the movements of the body in response to cardiac ejection of blood. The BCG signal can change considerably under various physiological states; however, little information exists in literature describing how these forces are generated. A physical analysis is presented using a finite element model of thoracic aortic vasculature to quantify forces generated by the blood flow during the cardiac cycle. The traction at the fluid-solid interface of this deformable wall model generates a Central Aortic Force (CAF) which appears of similar magnitude to recorded BCG forces. The increased pulse pressure in an exercise simulation caused a significant increase in CAF, which is consistent with recent BCG measurements in exercise recovery.

Evaluation and applications of optical cell density probes in mammalian cell bioreactors

On-line optical cell density probes were implemented to continuously monitor the cell densities in mammalian cell bioreactor and to achieve advanced bioreactor controls. We tested cell density probes from six manufacturers in high cell density bioreactors. When externally calibrated, Aquasant and Ingold backscattering probes produced the most linear probe responses (PR) versus cell density (CD), followed by the ASR and Cerex laser probes. Monitek and Wedgewood transmission probes had lower resolutions. All probes were tested in two murine hybridoma fermentations. Cell densities varied between 1 x 10(6) cells/mL to 20 x 10(6) cells/mL and the bioreactors were operated for 5 to 7 weeks. For our bioreactors, Aquasant, Ingold, ASR, Wedgewood, and Monitek probes gave satisfactory responses. Little fouling was observed with any probe at the end of 2 weeks. Fouling was a possibility after 3 weeks in one bioreactor but its effect can be easily corrected. Cell density control and specific perfusion control of bioreactors based on the Aquasant probe were achieved. Implementation of cell density probe based perfusion control, instead of "step perfusion adjustments" based on manual hemacytometer control, will result in smoother operation, healthier cultures, increased medium delivery efficiency, and reduced operational excursions.

Prenylated Rab acceptor protein is a receptor for prenylated small GTPases

Localization of Ras and Ras-like proteins to the correct subcellular compartment is essential for these proteins to mediate their biological effects. Many members of the Ras superfamily (Ha-Ras, N-Ras, TC21, and RhoA) are prenylated in the cytoplasm and then transit through the endomembrane system on their way to the plasma membrane. The proteins that aid in the trafficking of the small GTPases have not been well characterized. We report here that prenylated Rab acceptor protein (PRA1), which others previously identified as a prenylation-dependent receptor for Rab proteins, also interacts with Ha-Ras, RhoA, TC21, and Rap1a. The interaction of these small GTPases with PRA1 requires their post-translational modification by prenylation. The prenylation-dependent association of PRA1 with multiple GTPases is conserved in evolution; the yeast PRA1 protein associates with both Ha-Ras and RhoA. Earlier studies reported the presence of PRA1 in the Golgi, and we show here that PRA1 co-localizes with Ha-Ras and RhoA in the Golgi compartment. We suggest that PRA1 acts as an escort protein for small GTPases by binding to the hydrophobic isoprenoid moieties of the small GTPases and facilitates their trafficking through the endomembrane system.

Peroxisomal proteins in rat gametes

Peroxisomes are essential subcellular organelles, which appear to be derived from pre-existing organelles. This biogenetic mechanism assumes the presence of peroxisomes in either or both mammalian gametes (sperms and/or oocytes). In order to test the presence and subcellular localization of peroxisomal proteins in rat sperms and oocytes, the authors carried out fractionation and immunofluorescence experiments. The results showed that rat oocytes contain peroxisome-like structures, which were detected by indirect immunofluorescence, using an antisera against total peroxisomal proteins. In contrast, such structures were not detected in rat sperms, which appear to contain catalase localized in the cell cytosol. The results reported herein show evidence for the first time of the presence of peroxisome-like structures in mammalian oocytes, and provide evidence for the peroxisome biogenesis hypothesis, by division of pre-existing organelles.

[Clinical characterization of 450 patients with cerebrovascular disease admitted to a public hospital during 1997]

BACKGROUND

In Chile, cerebrovascular diseases are the fifth cause of death among men and the third cause among women.

AIM

To assess the clinical features and management of patients with cerebrovascular disease admitted to a public hospital during 1997.

PATIENTS AND METHODS

A retrospective analysis of clinical records of patients discharged with a diagnosis of cerebrovascular disease. Those records in which there was discordance between the discharge diagnosis and the clinical picture were not considered in the analysis.

RESULTS

Of the 563 discharges from the hospital with the diagnosis of cerebrovascular disease, 487 records were located and 450 were considered in the analysis. Fifty four percent of patients were male and ages ranged from 17 to 96 years old. Fifty-one percent of patients had an ischemic stroke, 34% a cerebral hemorrhage, 12% a subarachnoidal hemorrhage and 3% a transient ischemic attack. There was a history of hypertension in 64% patients and 20% had an adequate treatment. Eighteen percent were diabetics, 34% had a heart disease and 20% had a previous episode of stroke. Mean hospital stay was 6.3 days in the emergency room and 11 days in the neurology ward. Hospital infections appeared in 21% of patients (respiratory in 68% and urinary in 22%), lethality was 30.5% and a CAT scan was done in 94%. At the moment of admission, 10% of patients had an evolution of less than 2 hours, 27% had an evolution between 2 and 6 hours and nine cases were potential eligible for thrombolysis.

CONCLUSION

This is a picture of the local features of patients with cerebrovascular diseases that can be used as a reference for future studies.

Negative regulation of the serine/threonine kinase B-Raf by Akt

B-Raf contains multiple Akt consensus sites located within its amino-terminal regulatory domain. One site, Ser(364), is conserved with c-Raf but two additional sites, Ser(428) and Thr(439), are unique to B-Raf. We have investigated the role of both the conserved and unique phosphorylation sites in the regulation of B-Raf activity in vitro and in vivo. We show that phosphorylation of B-Raf by Akt occurs at multiple residues within its amino-terminal regulatory domain, at both the conserved and unique phosphorylation sites. The alteration of the serine residues within the Akt consensus sites to alanines results in a progressive increase in enzymatic activity in vitro and in vivo. Furthermore, expression of Akt inhibits epidermal growth factor-induced B-Raf activity and inhibition of Akt with LY294002 up-regulates B-Raf activity, suggesting that Akt negatively regulates B-Raf in vivo. Our results demonstrate that B-Raf activity can be negatively regulated by Akt through phosphorylation in the amino-terminal regulatory domain of B-Raf. This cross-talk between the B-Raf and Akt serine/threonine kinases is likely to play an important role in modulating the signaling specificity of the Ras/Raf pathway and in promoting biological outcome.

Allopurinol encapsulated in polycyanoacrylate nanoparticles as potential lysosomatropic carrier: preparation and trypanocidal activity

The activity of allopurinol-loaded polyethylcyanoacrylate nanoparticles against Trypanosoma cruzi was compared to that of free allopurinol using in vitro cultures of epimastigotes. Ethylcyanoacrylate nanoparticles were prepared by an emulsion polymerization process, and formulations containing different concentrations of allopurinol, polyethylcyanoacrylate and surfactants were investigated and analyzed in size and amount of drug entrapped. The nanoparticles obtained were less than 200 nm in size, as measured by electron microscopy and cytometry. The peak amount of allopurinol entrapped in the nanoparticles was 62.8+/-1.9 microg mg(-1) of nanoparticles using 400 microl of polyethylcyanoacrylate, 200 microl of surfactant (Tween 20) and 20 mg of allopurinol in 50 ml of polymerization medium and the association efficiency was 100.7%. After 6 h of incubation at pH 7.4 the release of allopurinol from the nanoparticles was 7.4%, while at pH 1.2 only 3.1% was released after 4-6 h (t=42.8, P<0.0001). The in vitro studies, using cultures of T. cruzi epimastigotes, demonstrated considerable increases in the trypanocidal activity of the allopurinol-loaded nanoparticles in comparison with a standard solution of allopurinol (91.5 vs. 45.9%) at an allopurinol concentration of 16.7 microg ml(-1). In addition, it was shown that the unloaded nanoparticles, by mechanisms not completely elucidated, had a trypanocidal activity similar to that of standard solutions of allopurinol. To study cytotoxicity, increasing concentrations of unloaded nanoparticles were incubated on vero-line cell cultures. The concentration that killed 50% cells was 200 microg ml(-1), four times higher than that necessary to kill 50% of T. cruzi. It is concluded that the polyethylcyanoacrylate nanoparticles constitute a good carrier of drugs against the T. cruzi. The allopurinol loaded-nanoparticles significantly increased the trypanocidal activity in comparison to the free drug.

The long-term reinfection rate and the course of duodenal ulcer disease after eradication of Helicobacter pylori in a developing country

OBJECTIVE

The aim of this study was to evaluate the effect of Helicobacter pylori (H. pylori) eradication on the natural history of duodenal ulcer disease and the reinfection rate after treatment in a developing country.

METHODS

A total of 111 H. pylori-infected patients with duodenal ulcer were treated with either omeprazole or famotidine plus two antibiotics for 2 wk. Those failed to respond to treatment were retreated with bismuth-based triple therapy.

RESULTS

The radication rate was 76% (95% CI: 67-83%). Eventually, H. pylori was eradicated in 96 of the 111 patients (86%), who were followed-up clinically and endoscopically for a mean of 37.2 months. The cumulative reinfection rate after eradication (Kaplan-Meier) was 8%+/-3% in yr 1, 11%+/-4% in yr 2, and 13%+/-4% in yr 3. Nine of the 12 reinfections occurred during yr 1. Recurrence of duodenal ulcer was detected in five patients (5.2%), all of them during yr 1 of follow-up. Histologically, gastritis scores (according to the Sydney system) improved significantly after eradication.

CONCLUSIONS

In a high prevalence setting, H. pylori eradication and early reinfection rates after treatment are similar to rates observed in a low prevalence environment, whereas the late reinfection rate seems to be higher. However, up to 3 yr after treatment, most treated patients are free of H. pylori infection and/or ulcer activity. Even longer follow-up studies are necessary to determine whether specific retreatment policies are necessary to maintain long term eradication in developing countries.

[Microbiological study of gallbladder bile in a high risk zone for gallbladder cancer]

BACKGROUND

Gallbladder cancer is frequent in Chile and there is sparse information about the association between this type of cancer and the presence of bacteria in the gallbladder bile.

AIM

To determine the presence of aerobic bacteria in gallbladder bile in patients with and without gallbladder cancer.

MATERIAL AND METHODS

A microbiological analysis of bile and pathological study was performed in 608 gallbladders, obtained during to cholecystectomies performed to 513 women and 95 men aged 44 years old as a mean.

RESULTS

Pathological study showed a chronic cholecystitis in 468 cases (77%), an acute cholecystitis in 140 (33%), cancer in 24 (3.9%) and dysplasia in 5 cases (0.8%). A positive culture was obtained in 22.5% of women and 28.5% of males. Twenty seven percent of women over 30 years old had positive cultures compared with 10% of younger women (p < 0.001). Thirty two percent of acute cholecystitis had positive cultures, compared with 24% of chronic cholecystitis (p = 0.03). E Coli was isolated in 51% of positive cases, Streptococci-Enterococci in 24%, Enterobacter sp in 9%, Klebsiella and Proteus in lower proportions. Salmonella sp was isolated in 4 cases, being all women with chronic cholecystitis. Thirteen of 29 cases with cancer or dysplasia had positive cultures (45%), compared with 25% of patients with inflammatory gallbladder diseases (p = 0.02). Streptococci-Enterococci were isolated in 7 cases and Enterobacter sp in three.

CONCLUSIONS

The presence of Salmonella sp in gallbladder bile was not frequent in the studied patients. Its role in the pathogenesis of gallbladder cancer must be reassessed.

Successful related umbilical cord blood transplantation for graft failure following T cell-depleted non-identical bone marrow transplantation in a child with major histocompatibility complex class II deficiency

Major histocompatibility complex (MHC) class II deficiency is a rare form of primary combined immunodeficiency that can only be corrected by stem cell transplantation. We report a 4(1/2)-year-old girl with MHC class II deficiency who underwent a related CBT due to graft failure following T cell-depleted non-identical BMT. The patient is alive and well 2 years after the second transplant. A sustained hematopoietic engraftment and a progressive immune recovery have been detected. We conclude that cord blood may be an effective source of hematopoietic stem cells for patients with immuno- deficiency disorders including diseases with a high rate of graft failure.

Improved success rate in reoperative parathyroidectomy with intraoperative PTH assay

OBJECTIVE

The clinical usefulness of preoperative localization and intraoperative PTH assay (QPTH) in primary hyperparathyroidism have been established. However, without the use of QPTH, the parathyroidectomy failure rate remains 5% to 10% in large reported series and is probably much higher in the hands of less experienced parathyroid surgeons. Persistent hypercalcemia requires another surgical procedure. The authors compared the outcomes in 50 consecutive patients undergoing more difficult secondary parathyroidectomy with and without the adjunctive support of QPTH.

METHODS

Two groups of similar patients underwent reoperative parathyroidectomy for failed surgery or recurrent disease. The successful return to normocalcemia in group I, with QPTH used to localize and confirm complete excision of all hyperfunctioning glands, was compared with group II, who did not have this intraoperative adjunct.

RESULTS

In 31/33 patients in group I, calcium levels returned to normal. With good preoperative localization studies, 17 patients underwent successful straightforward parathyroidectomies as predicted by QPTH. In the other 14 patients, QPTH assay proved extremely beneficial by facilitating localization with differential venous sampling; measuring the increase in hormone secretion after massage of specific areas; recognizing suspicious nonparathyroid tissue excised without a decrease in hormone levels, avoiding frozen-section delay; and correctly identifying the excision of abnormal tissue despite false-positive/false-negative sestamibi scans. In group II, who underwent surgery before QPTH was available, 4 of 17 patients (24%) remained hypercalcemic after extensive reexploration.

CONCLUSION

With the intraoperative hormone assay used to facilitate localization and confirm excision of all hyperfunctioning tissue, the success rate of reoperative parathyroidectomy has improved from 76% to 94%.

[Bone marrow transplantation for severe aplastic anemia]

Severe aplastic anemia is a hematological disease with a high mortality rate, for which bone marrow transplantation is the treatment of choice, specially in children and young adults. The number of transfusions undergone before the transplant is the most important factor to predict the possibility of graft failure. Twenty patients with severe aplastic anemia, most of them already multiple transfused, were transplanted utilizing cyclophosphamide combined with antilymphocyte globulin as a conditioning regiment. All the evaluable patients engrafted and there were no episodes of graft failure. Three patients died, and 17 (85%) are alive with hematopoietic recovery at a median of 27.7 months post-transplant. Bone marrow transplantation was an excellent therapeutic option in this series of patients with severe aplastic anemia and the conditioning regiment appeared to be sufficiently myeloablative and immunosuppressive to avoid early or late graft failure.

Accuracy of invasive and noninvasive tests to diagnose Helicobacter pylori infection after antibiotic treatment

OBJECTIVES

To compare the diagnostic accuracy of the most widely available tests for diagnosis of Helicobacter pylori infection after antibiotic treatment.

METHODS

A total of 59 H. pylori-positive, duodenal ulcer patients (mean age, 40.7 +/- 11.7 yr; 40 male and 19 female) were treated for 2 wk with either amoxicillin-metronidazole (n = 36) or omeprazole-amoxicillin-tinidazole (n = 23), and after 4 wk, were tested for H. pylori infection by [14C]urea breath test (UBT), serum IgG antibody level, and multiple antral biopsies for rapid urease testing, histology, Warthin-Starry stain, and polymerase chain reaction to detect H. pylori DNA. Infection status was established by a concordance of test results.

RESULTS

H. pylori was eradicated in 47 patients (80%). UBT and rapid urease testing had the best sensitivity and specificity, although not statistically different to Warthin-Starry stain and polymerase chain reaction. Serology and histology had little diagnostic value in this setting due to high proportion of false-positive results.

CONCLUSIONS

Noninvasive UBT is as accurate in predicting H. pylori status after antibiotic treatment as rapid urease testing and Warthin-Starry stain. Especially for duodenal ulcer patients, UBT could be considered the gold standard to confirm eradication of H. pylori.

Estrogen and luminal stimulation of rat uterine kallikrein

To understand the regulation of rat uterine kallikrein, we evaluated its variations in animals that had been ovariectomized and supplemented with estradiol or progesterone, in pseudopregnant animals intraluminally oil-stimulated or unstimulated, and in unilaterally pregnant animals. The content of kallikrein, determined by an RIA highly specific for rK1 (true tissue kallikrein), rose in ovariectomized rats with estradiol supplementation (0.28 +/- 0.03 to 0.44 +/- 0.05 ng/mg) and decreased with progesterone (0.13 +/- 0.02 ng/mg; n = 15; p < 0.001). Kallikrein content rose from Day 1 of pseudopregnancy (PP1) to a maximum on PP7 (0.18 +/- 0.01 to 0.39 +/- 0.04 ng/mg protein; n = 36; p < 0.001). On PP7 with unilateral oil intraluminal stimulation, the decidualized horn had higher kallikrein content than did the contralateral (0.98 +/- 0.09 vs. 0.35 +/- 0.05 ng/mg protein; n = 7; p < 0.001). Immunocytochemistry revealed that mainly rK1 is localized in the luminal and glandular epithelium, and it increased in the stimulated horn. In the unilaterally pregnant rat on Day 7, the fertile horn had a higher kallikrein content than its contralateral control (0.71 +/- 0.07 vs. 0.37 +/- 0.03 ng/mg protein, p < 0.001; n = 8), as well as a higher kininogenase activity (239 +/- 34.3 vs. 83.5 +/- 7.9 ng bradykinin(BK)/h per horn, p < 0.003; and 945 +/- 90 vs. 585 +/- 40 ng BK/h per gram tissue, p < 0.002; n = 6). These results indicate that estrogen stimulates, whereas progesterone inhibits, kallikrein production, and that hormonal regulation is overridden by intraluminal stimulation, thus associating the enzyme with decidualization.

Moderate expansion of a normally biallelic trinucleotide repeat in spinocerebellar ataxia type 2

The gene for spinocerebellar ataxia type 2 (SCA2) has been mapped to 12q24.1. A 1.1-megabase contig in the candidate region was assembled in P1 artificial chromosome and bacterial artificial chromosome clones. Using this contig, we identified a CAG trinucleotide repeat with CAA interruptions that was expanded in patients with SCA2. In contrast to other unstable trinucleotide repeats, this CAG repeat was not highly polymorphic in normal individuals. In SCA2 patients, the repeat was perfect and expanded to 36-52 repeats. The most common disease allele contained (CAG)37, one of the shortest expansions seen in a CAG expansion syndrome. The repeat occurs in the 5'-coding region of SCA2 which is a member of a novel gene family.

Enhanced biliary excretion of canalicular membrane enzymes in estrogen-induced and obstructive cholestasis, and effects of different bile acids in the isolated perfused rat liver

BACKGROUNDS/AIMS

Canalicular membrane enzymes are normally released into bile by partially known processes. This study was undertaken to investigate whether hepatocellular cholestatis induced in rats by ethynylestradiol or obstructive cholestasis produced by complete biliary obstruction for 24 h is associated with an increased release of alkaline phosphatase and gamma-glutamyl transpeptidase into bile, and to clarify how this process is affected by different bile acids.

METHODS

The studies were performed in the isolated perfused liver during infusion of sodium taurocholate, taurochenodeoxycholate and tauroursodeoxycholate at increasing rates.

RESULTS

Maximum sodium taurocholate, taurochenodeoxycholate and tauroursodeoxycholate secretory rates were decreased in both cholestatic groups (complete biliary obstruction > ethynylestradiol) compared with controls. Maximum biliary outputs of alkaline phosphatase and gamma-glutamyl transpeptidase were significantly increased in the ethynylestradiol group during infusion of sodium taurocholate and taurochenodeoxycholate, but not of tauroursodeoxycholate, and were increased in the complete biliary obstruction group during the infusion of sodium taurocholate and tauroursodeoxycholate but not of taurochenodeoxycholate. The biliary outputs of alkaline phosphatase and gamma-glutamyl transpeptidase showed a significant and direct linear relationship with sodium taurocholate and taurochenodeoxycholate secretory rates in both cholestatic groups. However, only in the complete biliary obstruction group did alkaline phosphatase and gamma-glutamyl transpeptidase excretion show a significant correlation with tauroursodeoxycholate secretory rates. The slope of the line, which indicated the mU of enzyme activity secreted per nmol of sodium taurocholate or taurochenodeoxycholate, was greater for gamma-glutamyl transpeptidase and alkaline phosphatase in both cholestatic groups (ethynylestradiol > complete biliary obstruction) than in the control group. Alkaline phosphatase activity in purified isolated canalicular and sinusoidal membranes was significantly increased in both cholestatic groups (complete biliary obstruction > ethynylestradiol), while gamma-glutamyl transpeptidase activity was unchanged compared with controls.

CONCLUSION

The marked increase in sodium taurocholate and taurochenodeoxycholate-mediated release of alkaline phosphatase and gamma-glutamyl transpeptidase into bile in cholestatic rats suggests an increased lability of these intrinsic membrane proteins to the detergent effects of secreted bile acids. It remains to be elucidated whether this phenomenon, which was particularly intense in ethynylestradiol induced cholestasis, is important in the pathogenesis and perpetuation of bile secretory failure. In contrast, tauroursodeoxycholate administration did not result in enhanced biliary excretion of these membrane enzymes, in either the control group or the ethynylestradiol group, supporting the concept that this bile salt lacks the membrane toxicity of common bile acids.

Identification of immunoreactive tissue kallikrein in human ductal breast carcinomas

Various proteases have been shown to be present in malignant breast tissue. Although the question of the involvement of tissue kallikrein, a serine protease, in the pathophysiology of tumours has been raised, the presence of this enzyme in human breast carcinoma has so far not been examined. In the present study, both neoplastic and normal human breast are scanned by immunocytochemistry for the presence and cellular localization of tissue kallikrein. In the healthy breast, tissue kallikrein was observed as a deposit of immunoreactive material that localized in the apical portion of duct cells. In the malignant breast tumours surveyed, the enzyme was observed only in ductal carcinomas, whereas lobular carcinomas were devoid of immunostaining. In ductal carcinomas, the immunoreactivity for tissue kallikrein appeared to be associated with gradations of malignancy, being absent in dedifferentiated tumours. The presence of tissue kallikrein in malignant breast tumours poses the question of the role of this enzyme in malignant breast tissue. The enzyme may participate within the tissue either in proteolytic processes (it has been shown to activate procollagenase) or by enhancing vascularity or mitogenicity by the generation of kinins.

Characterization of human peroxisomal membrane proteins

The peroxisomal membrane appears to play a crucial role in transporting proteins into the organelle. Some human genetic disorders involving peroxisome biogenesis, such as Zellweger syndrome, may be caused by genetic defects of the import machinery located in the peroxisomal membrane. In order to characterize the proteins of the human peroxisomal membrane, we isolated peroxisomes from human liver. We obtained their membranes using various procedures and analyzed their proteins by SDS-polyacrylamide gel electrophoresis and silver staining. We compared the protein composition of peroxisomal membranes with membranes derived from mitochondria and microsomes. The main peroxisomal membrane proteins (PMPs) have apparent molecular masses of 147, 112, 95, 87, 81, 79, 74, 69(70), 53-52 (double band), 47, 45, 43, 37, 31, 28, 22, and 17 kDa. The following PMPs of 147, 112, 79, 69(70), 53-52 (double band), 47, 43, 31, 28, 22, and 17 kDa fit the criteria for integral membrane proteins. We then produced rabbit polyclonal and mouse monoclonal antibodies that recognized some human PMPs. One of these antibodies detected mainly PMP43. We used this antiserum to evaluate the presence and subcellular distribution of the PMP43 in fibroblasts derived from patients affected by Zellweger syndrome. These results represent new information about the protein composition of the human peroxisomal membrane and provide biological tools for further characterization of the human PMPs and their genes in normal and pathological conditions.

Identification of kallikrein in cultures of adult renal cells

Cortical tubular cultures enriched with distal segments were prepared from the kidney of adult Fisher 344 rats bearing thyroid tumors. After two years of cultivation (20 passages) cell monolayers contained immunocytochemically detectable cytokeratin and kallikrein material in their cytoplasm. Furthermore cell pellets showed a true renal type of kininogenase activity corresponding to active kallikrein which ranged from 22.3 to 1.5, and total Kallikrein from 29.9 to 2.8 pg kinins/min per mg of protein.