Genitourinary symptoms and sexual function in women with primary ovarian insufficiency

OBJECTIVE

There are limited studies on urogenital symptoms in women who experience menopause before the age of 40 years due to primary ovarian insufficiency (POI) or bilateral oophorectomy (surgical POI). This study aimed to compare the urogenital symptoms, including sexuality, of women with POI to those without the condition.

METHODS

This cross-sectional study conducted was in seven Latin American countries, in which postmenopausal women (with POI and non-POI) were surveyed with a general questionnaire, the Menopause Rating Scale (MRS) and the six-item Female Sexual Function Index (FSFI-6). The association of premature menopause with more urogenital symptoms and lower sexual function was evaluated with logistic regression analysis.

RESULTS

Women with POI experience more urogenital symptoms (MRS urogenital score: 3.54 ± 3.16 vs. 3.15 ± 2.89, p < 0.05) and have lower sexual function (total FSFI-6 score: 13.71 ± 7.55 vs. 14.77 ± 7.57 p < 0.05) than women who experience menopause at a normal age range. There were no significant differences in symptoms when comparing women based on the type of POI (idiopathic or surgical). After adjusting for covariates, our logistic regression model determined that POI is associated with more urogenital symptoms (odds ratio [OR]: 1.38, 95% confidence interval [CI] 1.06-1.80) and lower sexual function (OR: 1.67, 95% CI 1.25-2.25).

CONCLUSION

POI, whether idiopathic or secondary to bilateral oophorectomy, is associated with symptoms that affect vaginal and sexual health.

Functionalized bioadhesion-enhanced carboxymethyl cellulose/polyvinyl alcohol hybrid hydrogels for chronic wound dressing applications

Wounds produced by trauma, burns, and chronic diseases cause millions of patients to suffer discomfort, pain, and, in many cases, disability and death, leading to enormous health, social and financial impacts globally. Regrettably, current clinical treatments for chronic wounds remain unsatisfactory. Thus, this study reports for the first time the design, development, and synthesis of chemically biofunctionalized hybrid hydrogels made of carboxymethyl cellulose (CMC) and poly(vinyl alcohol) (PVA) crosslinked by citric acid using an entirely biocompatible and green process. They demonstrated suitable physicochemical properties, cytocompatibility, and hemocompatibility to be applied as a smart wound dressing for skin tissue engineering. These novel hybrids were biofunctionalized with l-arginine and RGD peptide through carbodiimide mediated-amide formation to promote bioadhesion of fibroblast and keratinocyte cells as a potential enhancement for wound healing and skin tissue engineering applications.

Botulinum toxin in the treatment of residual limb hyperhidrosis: A systematic review

The aim of the study was to analyze the current evidence regarding the effect of intradermal injections of botulinum toxin on residual limb hyperhidrosis. A comprehensive search of the MEDLINE and Scopus databases from inception until December 2021 was performed according to the PRISMA guidelines. The search terms used were "botulinum toxins", "botulinum toxins, Type A", "rimabotulinumtoxinB", "amputees", "amputation stumps", "amputation" and "residual limbs". The specific controlled vocabulary of each database was also used (e.g., MeSH). One hundred and thirty-one different studies met this search criteria and were reviewed. Two independent reviewers assessed the quality of the manuscripts. Eight studies met the inclusion criteria for this review. The results demonstrated an improvement in residual limb hyperhidrosis in all studies. Botulinum toxin A or B can be regarded as safe and effective for the treatment of residual limb hyperhidrosis, as well as improving prosthesis use and quality of life.

Antimicrobial profile of a dental implant abutment coating to prevent adhesion and migration of bacteria and screw loosening

OBJECTIVE

Failure of dental implants treatment is frequently the result of bacterial colonization of implants followed by diseases like peri-implantitis. Recent studies have been made regarding the surface treatment of implants components, namely abutments that are in the interface of the living tissue with the implant. This work aimed at evaluating the antimicrobial profile of a silane-based coating with TiO₂ adapted to an abutment screw, that was also developed as an anti-loosening agent, to prevent adhesion and migration of Gram + and Gram-bacteria, Staphylococcus aureus, and Escherichia coli, respectively.

METHODS

Direct contact antimicrobial studies were conducted on coated and uncoated samples by resazurin fluorescent assay and cytotoxicity assessment was done via MTT indirect method on days 1 and 4. Sterilizations studies by FTIR analysis were also performed to understand the ideal balance between sterilization efficacy and coating functionality subjecting the samples to ethylene oxide, gamma irradiation, and autoclave sterilization, before antimicrobial testing. The implant system as a whole was also studied for its ability to block bacterial migration and preventing microleakage as well as an assessment of initial bacterial adhesion evaluated by scanning electron microscopy.

RESULTS

Direct contact studies performed on coated samples showed a very high antimicrobial activity, while cytotoxicity assays revealed the coating to be safe and non-leachable. Sterilizations studies showed that the antimicrobial features of the coating were preserved and interchangeable regardless of the sterilization method. The implant system migration studies demonstrated that the implant system works as an efficient barrier for the studied bacteria.

SIGNIFICANCE

The acquired results clearly show that it is possible to obtain a highly functional coating with obvious and marked antimicrobial features that together with an abutment that prevents bacterial migration and versatility in sterilization methodology has a very high potential in the dental implant field.

Development of asymmetric resorbable membranes for guided bone and surrounding tissue regeneration

Membranes design for guided tissue engineering have been studied to aid in cell viability and function as tissue barriers. Two asymmetric resorbable membranes for guided bone regeneration (GBR) were produced: chitosan/pectin/poly-caprolactone (PECm) and poly(vinyl alcohol)/polyethylenimine/poly(ethylene glycol) (PVAm). Both membranes were characterized by physical, chemical, mechanical, degradation rate, and in vitro biological assessment. Scanning electron microscopy (SEM) confirmed the membranes asymmetry, in which PECm asymmetry is given by roughness and chemical composition, while PVAm's only by differences in porosity. Fourier transform infrared spectroscopy (FTIR) identified chemical groups and bonds between polymers. Both sides of PVAm revealed to be hydrophobic, whereas the PECm presented one side with higher hydrophobicity than the other. In vitro biological assessment disclosed that PECm presented a higher cell adhesion growth pattern than PVAm, where it seemed to occur a delay in proliferation due to initial low cell adhesion. Both developed membranes are suitable for GBR, since both membranes fulfil the requirements to be used as a tissue barrier. The PECm has an additional role in cell viability that was not observed in the PVAm. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2141-2150, 2018.

Down-Klinefelter syndrome (48,XXY,+21) in a neonate associated with congenital heart disease

Double aneuploidy is considered a rare phenomenon. Herein, we describe a case of double aneuploidy 48,XXY,+21 in a neonate with congenital heart defects. The 28-day-old neonate male (23-year-old mother and 24-year-old father) was admitted to a neonatal intensive care unit owing to congenital heart disease. Echocardiography showed a complete atrioventricular septal defect with Rastelli type B and significant left ventricular failure, moderate atrioventricular valve regurgitation, right-sided heart failure, and preserved systolic function. Cytogenetic analysis of the newborn showed double aneuploidy 48,XXY,+21. The maternal karyotype was 46,XX,inv(9)(p11q13) and the paternal was 46,XY. Characteristics associated with Down syndrome are observed in newborns; on the other hand, children under 10 months of age and neonates may show little or no signs of the Klinefelter syndrome. According to this study, there seem to be differences between the frequency of congenital heart disease among patients with Down-Klinefelter and Down syndrome. At about 11 months of age, the child died after undergoing heart surgeries. The early cytogenetic study is important for better diagnosis and management of the disease.

Imaging features of intracerebral hemorrhage with cerebral amyloid angiopathy: Systematic review and meta-analysis

BACKGROUND

We sought to summarize Computed Tomography (CT)/Magnetic Resonance Imaging (MRI) features of intracerebral hemorrhage (ICH) associated with cerebral amyloid angiopathy (CAA) in published observational radio-pathological studies.

METHODS

In November 2016, two authors searched OVID Medline (1946-), Embase (1974-) and relevant bibliographies for studies of imaging features of lobar or cerebellar ICH with pathologically proven CAA ("CAA-associated ICH"). Two authors assessed studies' diagnostic test accuracy methodology and independently extracted data.

RESULTS

We identified 22 studies (21 cases series and one cross-sectional study with controls) of CT features in 297 adults, two cross-sectional studies of MRI features in 81 adults and one study which reported both CT and MRI features in 22 adults. Methods of CAA assessment varied, and rating of imaging features was not masked to pathology. The most frequently reported CT features of CAA-associated ICH in 21 case series were: subarachnoid extension (pooled proportion 82%, 95% CI 69-93%, I2 = 51%, 12 studies) and an irregular ICH border (64%, 95% CI 32-91%, I2 = 85%, five studies). CAA-associated ICH was more likely to be multiple on CT than non-CAA ICH in one cross-sectional study (CAA-associated ICH 7/41 vs. non-CAA ICH 0/42; χ2 = 7.8, p = 0.005). Superficial siderosis on MRI was present in 52% of CAA-associated ICH (95% CI 39-65%, I2 = 35%, 3 studies).

CONCLUSIONS

Subarachnoid extension and an irregular ICH border are common imaging features of CAA-associated ICH, but methodologically rigorous diagnostic test accuracy studies are required to determine the sensitivity and specificity of these features.

CASE-REPORT Low-level trisomy 14 mosaicism in a male newborn with ectrodactyly

Complete trisomy 14 mosaicism is a rare chromosome disorder and was first reported in 1970. We describe a case of a male neonate who presented complete trisomy 14 mosaicism in only 4% of the cells from peripheral blood. A nineteen-day-old male neonate was born as result of the second pregnancy. The infant was delivered by cesarean section due to gestational hypertension and chronic fetal distress. The length of the term pregnancy was 37 weeks, the birth weight was 3.105 g, the length was 48 cm, and the head circumference was 35.5 cm. The baby remained hospitalized for 19 days in the neonatal intensive care unit due to respiratory distress syndrome and congenital malformations. Physical examination revealed a toned and normal activity, followed by phenotypic changes such as a broader forehead, formation of a cleft palate, hypertelorism, low-set ears, bilateral cryptorchidism, absence of the second toe of the left foot (ectrodactyly), and fusion of third and fourth toes in the right foot (bilateral syndactyly). Cytogenetic analysis was performed on peripheral blood cultures after hospitalization in the neonatal intensive care unit. Analysis of 200 G-banded metaphases showed that 192 (96%) had normal karyotype 46,XY and only 8 (4%) presented trisomy 47,XY,+14. It was not possible to perform cytogenetic analysis on the patient's parents. Our patient represents the first case of trisomy 14 disorder to present ectrodactyly.

THE EFFECT OF AN OPTIMIZED IMAGING FLOW CYTOMETRY ANALYSIS TEMPLATE ON SAMPLE THROUGHPUT IN THE REDUCED CULTURE CYTOKINESIS-BLOCK MICRONUCLEUS ASSAY

In cases of overexposure to ionizing radiation, the cytokinesis-block micronucleus (CBMN) assay can be performed in order to estimate the dose of radiation to an exposed individual. However, in the event of a large-scale radiation accident with many potentially exposed casualties, the assay must be able to generate accurate dose estimates to within ±0.5 Gy as quickly as possible. The assay has been adapted to, validated and optimized on the ImageStream^X imaging flow cytometer. The ease of running this automated version of the CBMN assay allowed investigation into the accuracy of dose estimates after reducing the volume of whole blood cultured to 200 µl and reducing the culture time to 48 h. The data analysis template used to identify binucleated lymphocyte cells (BNCs) and micronuclei (MN) has since been optimized to improve the sensitivity and specificity of BNC and MN detection. This paper presents a re-analysis of existing data using this optimized analysis template to demonstrate that dose estimations from blinded samples can be obtained to the same level of accuracy in a shorter data collection time. Here, we show that dose estimates from blinded samples were obtained to within ±0.5 Gy of the delivered dose when data collection time was reduced by 30 min at standard culture conditions and by 15 min at reduced culture conditions. Reducing data collection time while retaining the same level of accuracy in our imaging flow cytometry-based version of the CBMN assay results in higher throughput and further increases the relevancy of the CBMN assay as a radiation biodosimeter.

Sentinel node biopsy using blue dye and technetium99 in advanced gastric cancer: anatomical drainage and clinical application

Lymph node metastases are an independent prognosis factor in gastric carcinoma (GC) patients. Radical lymphadenectomy can improve survival but it can also increase surgical morbidity. As a principle, sentinel node (SN) navigation surgery can avoid unnecessary lymphadenectomy without compromising prognosis. In this pilot study, 24 patients with untreated GC were initially screened for SN navigation surgery, of which 12 were eligible. Five patients had T2 tumors, 5 had T3 tumors and 2 had T1 tumors. In 33% of cases, tumor diameter was greater than 5.0 cm. Three hundred and eighty-seven lymph nodes were excised with a median of 32.3 per patient. The SN navigation surgery was feasible in all patients, with a median of 4.5 SNs per patient. The detection success rate was 100%. All the SNs were located in N1 and N2 nodal level. In 70.9% of cases, the SNs were located at lymphatic chains 6 and 7. The SN sensitivity for nodal staging was 91.6%, with 8.3% of false negative. In 4 patients who were initially staged as N0, the SNs were submitted to multisection analyses and immunohistochemistry, confirming the N0 stage, without micrometastases. In one case initially staged as negative for nodal metastases based on SN analyses, metastases in lymph nodes other than SN were found, resulting in a 20% skip metastases incidence. This surgery is a reproducible procedure with 100% detection rate of SN. Tumor size, GC location and obesity were factors that imposed some limitations regarding SN identification. Results from nodal multisection histology and immunohistochemistry analysis did not change initial nodal staging.

Optimized automated data analysis for the cytokinesis-block micronucleus assay using imaging flow cytometry for high throughput radiation biodosimetry

The cytokinesis-block micronucleus (CBMN) assay is a well-established technique that can be employed in triage radiation biodosimetry to estimate whole body doses of radiation to potentially exposed individuals through quantitation of the frequency of micronuclei (MN) in binucleated lymphocyte cells (BNCs). The assay has been partially automated using traditional microscope-based methods and most recently has been modified for application on the ImageStream(X) (IS(X) ) imaging flow cytometer. This modification has allowed for a similar number of BNCs to be automatically scored as compared to traditional microscopy in a much shorter time period. However, the MN frequency measured was much lower than both manual and automated slide-based methods of performing the assay. This work describes the optimized analysis template which implements newly developed functions in the IDEAS(®) data analysis software for the IS(X) that enhances specificity for BNCs and increases the frequency of scored MN. A new dose response calibration curve is presented in which the average rate of MN per BNC is of similar magnitude to those presented in the literature using automated CBMN slide scoring methods. In addition, dose estimates were generated for nine irradiated, blinded samples and were found to be within ±0.5 Gy of the delivered dose. Results demonstrate that the improved identification accuracy for MN and BNCs in the IS(X) -based version of the CBMN assay will translate to increased accuracy when estimating unknown radiation doses received by exposed individuals following large-scale radiological or nuclear emergencies. © 2016 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of ISAC.

Multi-parameter dose estimations in radiation biodosimetry using the automated cytokinesis-block micronucleus assay with imaging flow cytometry

The cytokinesis-block micronucleus (CBMN) assay is an established technique in radiation biological dosimetry for estimating the dose to an individual by measuring the frequency of micronuclei (MN) in binucleated lymphocyte cells (BNCs). The assay has been partially automated using slide-scoring algorithms, but an automated multiparameter method without the need of the slide-making procedure would be advantageous to further increase throughput for application in mass casualty events. The development of the ImageStreamX (ISX) imaging flow cytometer has made it possible to adapt the CBMN assay to an automated imaging flow cytometry (FCM) method. The protocol and analysis presented in this work tailor and expand the assay to a multiparameter biodosimetry tool. Ex vivo irradiated whole blood samples were cultured, processed, and analyzed on the ISX and BNCs, MN, and mononuclear cells were imaged, identified, and enumerated automatically and simultaneously. Details on development of the method, gating strategy, and dose response curves generated for the rate of MN per BNC, percentage of mononuclear cells as well as the replication index are presented. Results indicate that adapting the CBMN assay for use in imaging FCM has produced a rapid, robust, multiparameter analysis method with higher throughput than is currently available with standard microscopy. We conclude that the ISX-CBMN method may be an advantageous tool following a radiological event where triage biodosimetry must be performed on a large number of casualties.

Automated analysis of the cytokinesis-block micronucleus assay for radiation biodosimetry using imaging flow cytometry

The cytokinesis-block micronucleus (CBMN) assay is employed in biological dosimetry to determine the dose of radiation to an exposed individual from the frequency of micronuclei (MN) in binucleated lymphocyte cells. The method has been partially automated for the use in mass casualty events, but it would be advantageous to further automate the method for increased throughput. Recently, automated image analysis has been successfully applied to the traditional, slide-scoring-based method of the CBMN assay. However, with the development of new technologies such as the imaging flow cytometer, it is now possible to adapt this microscope-based assay to an automated imaging flow cytometry method. The ImageStream(X) is an imaging flow cytometer that has adequate sensitivity to quantify radiation doses larger than 1 Gy while adding the increased throughput of traditional flow cytometry. The protocol and analysis presented in this work adapts the CBMN assay for the use on the ImageStream(X). Ex vivo-irradiated whole blood samples cultured for CBMN were analyzed on the ImageStream(X), and preliminary results indicate that binucleated cells and MN can be identified, imaged and enumerated automatically by imaging flow cytometry. Details of the method development, gating strategy and the dose response curve generated are presented and indicate that adaptation of the CBMN assay for the use with imaging flow cytometry has potential for high-throughput analysis following a mass casualty radiological event.

Biological evaluation of alginate-based hydrogels, with antimicrobial features by Ce(III) incorporation, as vehicles for a bone substitute

A novel hydrogel, based on an alginate/hyaluronate mixture and Ce(III) ions, with effective bioactive and antimicrobial ability was developed to be used as vehicle of a synthetic bone substitute producing an injectable substitute (IBS). Firstly, three different IBSs were prepared using three developed alginate-based hydrogels, the hydrogel Alg composed by alginate, the hydrogel Alg/Ch composed by an alginate/chitosan mixture and the hydrogel Alg/HA composed by an alginate/hyaluronate mixture. MG63 cells viability on the IBSs was evaluated, being observed a significantly higher cell viability on the Alg/HA_IBS at all time points, which indicates a better cell adaptation to the material, increasing their predisposition to produce extracellular matrix and thus allowing a better bone regeneration. Moreover, SEM analysis showed evident filopodia and a spreader shape of MG63 cells when seeded on Alg/HA_IBS. This way, based upon the in vitro results, the hydrogel Alg/HA was chosen to the in vivo study by subcutaneous implantation in an animal model, promoting a slight irritating tissue response and visible tissue repairing. The next step was to grant antimicrobial properties to the hydrogel that showed the best biological behavior by incorporation of Ce(III) ions into the Alg/HA, producing the hydrogel Alg/HA2. The antimicrobial activity of these hyaluronate-based hydrogels was evaluated against Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa and Candida albicans. Results showed that Ce(III) ions can significantly enhance the hydrogel antimicrobial ability without compromising the osteoconductivity improvement promoted by the vehicle association to the synthetic bone substitute.

Physical activity and amyloid-β plasma and brain levels: results from the Australian Imaging, Biomarkers and Lifestyle Study of Ageing

Previous studies suggest physical activity improves cognition and lowers Alzheimer's disease (AD) risk. However, key AD pathogenic factors that are thought to be influenced by physical activity, particularly plasma amyloid-β (Aβ) and Aβ brain load, have yet to be thoroughly investigated. The objective of this study was to determine if plasma Aβ and amyloid brain deposition are associated with physical activity levels, and whether these associations differed between carriers and non-carriers of the apolipoprotein E (APOE) ε4 allele. Five-hundred and forty six cognitively intact participants (aged 60-95 years) from the Australian Imaging, Biomarkers and Lifestyle Study of Ageing (AIBL) were included in these analyses. Habitual physical activity levels were measured using the International Physical Activity Questionnaire (IPAQ). Serum insulin, glucose, cholesterol and plasma Aβ levels were measured in fasting blood samples. A subgroup (n=116) underwent (11)C-Pittsburgh compound B (PiB) positron emission tomography (PET) scanning to quantify brain amyloid load. Higher levels of physical activity were associated with higher high density lipoprotein (HDL) (P=0.037), and lower insulin (P<0.001), triglycerides (P=0.019) and Aβ1-42/1-40 ratio (P=0.001). After stratification of the cohort based on APOE ε4 allele carriage, it was evident that only non-carriers received the benefit of reduced plasma Aβ from physical activity. Conversely, lower levels of PiB SUVR (standardised uptake value ratio) were observed in higher exercising APOE ε4 carriers. Lower plasma Aβ1-42/1-40 and brain amyloid was observed in those reporting higher levels of physical activity, consistent with the hypothesis that physical activity may be involved in the modulation of pathogenic changes associated with AD.

Incidental meandering right pulmonary vein, literature review and proposed nomenclature revision

We report a case of an anomalous pulmonary vein on chest X-ray resembling a scimitar sign in an 80-year-old female undergoing investigation of syncope. Multislice computed tomography (CT) with multiplanar reformatting and maximum intensity projections demonstrated an aberrant right inferior pulmonary vein coursing inferomedially towards the diaphragm before turning superiorly and draining normally into the left atrium. The diagnosis of an incidental meandering right pulmonary vein was established. The case is used to review the literature on this rare pulmonary anomaly, including pathogenesis, its relationship with scimitar syndrome and scimitar variant, and diagnosis, with an emphasis on the role modern CT techniques can play in non-invasive diagnosis. A revision to the nomenclature of pulmonary vascular anomalies is proposed to help reduce confusion in the literature.

Knowledge of Clostridium difficile infection among UK health-care workers: development of a knowledge assessment tool

Doctors’ knowledge provides the basis to support good practice in infection prevention and control. However, there exists a paucity of validated knowledge assessment tools that can be reliably employed to identify poor knowledge levels of Clostridium difficile infection (CDI) within populations of doctors, preventing the effective identification of knowledge deficiencies and focused targeting of educational interventions. Here, we describe a development process to validate a novel CDI knowledge assessment tool for doctors. Two previously published CDI knowledge questionnaires were amalgamated to produce a combined questionnaire. Content was further evaluated by a panel of CDI experts, producing the ‘Lothian’ questionnaire. These questionnaires were tested in control populations comprising either infection control nurse (ICN) specialists or non-clinically trained individuals, and a cohort of medical staff. We compared the efficacy of the ‘Lothian’ questionnaire against that of previous questionnaire reports. We found that all of the questionnaires studied significantly discriminated between non-clinical and clinical populations (ICNs and medical staff) ( P < 0.001) and had similar levels of sensitivity and specificity in discrimination between these targeted populations. This study describes the development of a robust CDI knowledge assessment tool that can be used to evaluate knowledge levels among doctors, compare populations and assist the targeting of educational interventions and plot trends following such interventions.

Clostridium difficile infection in general surgery patients; identification of high-risk populations

BACKGROUND

Risk factors associated with Clostridium difficile infection (CDI) in general surgical patients are poorly characterised. This study aimed to characterise the incidence and associations of C. difficile positivity (CDP) in general surgical inpatients to aid in the design of future policies regarding focused screening and risk-stratification mechanisms in this patient subpopulation.

MATERIALS AND METHODS

Discharge, laboratory and coding data from all general surgery inpatients admitted to a large tertiary referral general surgical unit, between March 2005 and May 2007, were examined.

RESULTS

21,371 patient records were interrogated. 101 (0.47%) CDP cases were identified from laboratory records and compared with non-CDP controls for age, gender, length of stay (LOS), admission to intensive care unit or high dependency unit (ICU/HDU), co-morbidities and surgical procedures. Univariate analysis identified a range of risk factors associated with positivity. Multivariate analysis identified malignancy, gastrointestinal disease, anaemia, respiratory disease, circulatory disease, diabetes mellitus, those undergoing gastrointestinal surgery and increasing age to be independently associated with CDP status.

CONCLUSIONS

This study identifies incidence and risk factor associations of those who tested CDP in a large contemporary general surgery inpatient population. Focused screening programmes based on high-risk populations may provide information on further risk factors and allow risk-stratification. Further healthcare worker education regarding risk factors may reduce the clinical impact of CDI by encouraging increased vigilance and therefore earlier detection.

Nuclear calcium signaling: a cell within a cell

Calcium (Ca2+) is a versatile second messenger that regulates a wide range of cellular functions. Although it is not established how a single second messenger coordinates diverse effects within a cell, there is increasing evidence that the spatial patterns of Ca2+ signals may determine their specificity. Ca2+ signaling patterns can vary in different regions of the cell and Ca2+ signals in nuclear and cytoplasmic compartments have been reported to occur independently. No general paradigm has been established yet to explain whether, how, or when Ca2+ signals are initiated within the nucleus or their function. Here we highlight that receptor tyrosine kinases rapidly translocate to the nucleus. Ca2+ signals that are induced by growth factors result from phosphatidylinositol 4,5-bisphosphate hydrolysis and inositol 1,4,5-trisphosphate formation within the nucleus rather than within the cytoplasm. This novel signaling mechanism may be responsible for growth factor effects on cell proliferation.

Effect of light reduction on the incidence of retinopathy of prematurity

The effect of ocular protection on the incidence of retinopathy of prematurity was tested in 188 newborns weighing less than 1600 g in a randomised controlled trial. No effect of ambient light reduction on the incidence of retinopathy of prematurity was shown.

Invasive enteritis by Strongyloides stercoralis presenting as acute abdominal distress under corticosteroid therapy

Overwhelming helminthiasis is still a problem in endemic areas, especially in immunocompromised patients. We report a case of invasive intestinal strongyloidiasis that was clinically expressed as acute abdominal distress in a 73-year-old man from São Paulo who had been receiving methylprednisone, 20 mg/day, for one year for osteoarthritis. A surgical specimen from the ileum revealed invasive enteritis with severe infestation by Strongyloides stercoralis. The patient died of sepsis 6 days after surgery. The possibility of invasive strongyloidiasis should be considered in the differential diagnosis of acute abdominal distress in patients undergoing immunosuppressive therapy.

A biomechanical model of the upper airways for simulating laryngoscopy

This paper describes a three-dimensional finite element model of the human upper airways during rigid laryngoscopy. In this procedure, an anaesthetist uses a rigid blade to displace and compress the tongue of the patient, and then inserts a tube into the larynx to allow controlled ventilation of the lungs during an operation. A realistic model of the main biomechanical aspects involved would help anaesthetists in training and in predicting difficult cases in advance. For this purpose, the finite element method was used to model structures such as the tongue, ligaments, larynx, vocal cords, bony landmarks, laryngoscope blade, and their inter-relationships, based on data extracted from X-ray, MRI, and photographic records. The model has been used to investigate how the tongue tissue behaves in response to the insertion of the laryngoscope blade, when it is subjected to a variety of loading conditions. In particular, the mechanical behaviour of the soft tissue of the tongue was simulated, from simple linear elastic material to complex non-linear viscoelastic material. The results show that, within a specific set of tongue material parameters, the simulated outcome can be successfully related to the view of the vocal cords achieved during real laryngoscopies on normal subjects, and on artificially induced difficult laryngoscopy, created by extending the upper incisors teeth experimentally.

Posterior approach for soft cervical disc herniation: a neglected technique?

BACKGROUND

The ideal approach to the treatment of soft cervical disc herniation remains controversial. Recent reports emphasize several variations of anterior cervical approaches, including the introduction of instrumentation techniques. New issues have been raised and modern neurosurgeons seem to be less familiar with the posterior approach. The objective of this study was to analyze the results obtained by surgical treatment via a posterior approach of soft cervical disc herniation.

METHOD

Fifty-one patients who underwent laminectomy/flavectomy and disc removal for the treatment of soft cervical disc herniation in the period of 1990 to 1999 were analyzed retrospectively. Relief of pain and motor and sensory improvement were the criteria used to measure the success of the procedure.

RESULTS

Most of the patients presented with acute radiculopathy. Radicular involvement was as follows: 25 cases-C7 root, 19 cases-C6 root, 4 cases-C5 root, and 3 cases-C8 root. Total relief of pain was obtained in 49 of 51 patients (96%). Motor improvement was obtained in 35 of 46 patients (76%) and sensory improvement in 22 of 35 patients (62.8%) in the short term. The mean time of hospitalization was 3 days. There was no mortality and no morbidity.

CONCLUSION

The advantage of this method, in selected cases, over the classical anterior approach, is that there is no need for grafting, thus avoiding the additional pain and possible complications at the donor and receptor sites, while obtaining similar results.

Early and late effects of wound healing on development of colon tumours in a model of colon carcinogenesis by 1,2-dimethylhydrazine in the rat

The early and late effects of wound healing on tumour development at a distant site were evaluated morphologically in an experimental model of colon carcinogenesis induced by 1,2-dimethylhydrazine (DMH). Random bred male Wistar rats were given subcutaneous injections of DMH (20 mg/kg) or saline, once a week, for eight weeks. One week after the last DMH injection the animals received a full thickness skin wound in their dorsal skin and the wound was left open to heal by second intention. Control and DMH treated rats, with or without skin wounds were sacrificed at the twelfth and twentieth weeks. The colons were removed and the incidence, distribution and morphology of any tumours were recorded. Tumours induced by DMH in the colonic mucosa increased in size during the experiment. At the twelfth week, just after healing of the skin wound was complete, the total number of tumours in the colonic mucosa and the number of tumours per rat was significantly higher in the skin-wounding DMH-treated group than in the unwounded group. No differences on tumour incidence and multiplicity were observed among the groups at the twentieth week. Histologically the number of poorly differentiated mucin-secreting carcinomas was increased in the skin-wounding DMH-treated group than in the unwounded group at the twelfth week. This effect was not observed at the twentieth week. The present results suggest that wound healing enhances tumour development at a distant site. This effect coincides with the period of repair and does not have a marked impact on later stages of tumour progression.

Gastric cryptosporidiosis as a clue for the diagnosis of the acquired immunodeficiency syndrome

Cryptosporidium parvum has been detected with increasing frequency in the gastrointestinal tract, but involvement of the stomach is rarely reported. Whenever found in the histologic examination of the gastrointestinal mucosa, it should raise the suspicion of an immunocompromised host. We report a case of Cryptosporidium-associated erosive gastritis in a 64-year-old woman, who was found later to have the acquired immunodeficiency syndrome. Gastroduodenoendoscopy and biopsy of the gastric mucosa played an invaluable role in the diagnosis of cryptosporidiosis and to disclose the underlying immunodeficiency state.

Promotion of hepatocarcinogenesis by hexachlorobenzene in energy-restricted rats

The interaction between dietary energy restriction and low dose of the fungicide hexachlorobenzene (HCB) was evaluated in a rat liver medium-term bioassay for carcinogenesis. Male Wistar rats were fed a control or a 50% energy-restricted diet, both added or not with 50 ppm HCB, for 6 weeks. HCB exposure or energy restriction separately did not exert any influence on the development of glutathione S-transferase placental form (GST-P(+)) foci of hepatocytes. Simultaneous HCB exposure and energy restriction induced a significant increase in liver centrilobular hypertrophy and GST-P(+) foci development. Our findings suggest that energy restriction increases liver response to low dose of HCB, unmasking the promoting potential of this fungicide.

Dose- and sex-related carcinogenesis by N-bis(2-hydroxypropyl)nitrosamine in Wistar rats

An initiation-promotion medium-term bioassay for detection of chemical carcinogens, developed in the male F344 rat, uses 0.1% N-bis(2-hydroxypropyl)nitrosamine (DHPN) among five genotoxic chemicals for the initiation of carcinogenesis in multiple organs. To establish this bioassay in the Wistar strain, the effects of two dose levels of DHPN were evaluated on the main DHPN rat target organs: lung, thyroid gland, kidneys and liver. Four groups of male and female animals were studied: Control -- untreated group; Multi-organ initiated group (also referred to as DMBDD, based on the initials of the five initiators) -- treated sequentially with N-diethylnitrosamine (DEN, i.p.), N-methyl-N-nitrosourea (MNU, i.p.), N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN, drinking water), N, N'-dimethylhydrazine (DMH, s.c.) and DHPN (drinking water) for 4 weeks; a third group treated with 0.1% DHPN in drinking water for 2 weeks and the last group treated with 0.2% DHPN in drinking water for 4 weeks. The animals were sacrificed after 30 weeks. DHPN at 0. 2% induced preneoplasia in the liver and kidneys of rats of both sexes, the number and area of the putative preneoplastic liver glutathione S-transferase-positive hepatocyte foci being significantly increased in these animals. It also induced benign and malignant tumors in female and in male rats. However, there was no relationship between the increased incidence of preneoplastic lesions and tumor development in the 0.2% DHPN-exposed groups of both sexes. DHPN at 0.1% induced only a few preneoplastic lesions in the liver and kidney and no tumors in both male and female rats. A clear dose and sex-related carcinogenic activity of DHPN was registered, although Wistar rats of both sexes showed a relative resistance to the carcinogenic activity of this compound.

Comparison of omega-3 fatty acids and sulfasalazine in ulcerative colitis

Fish oil omega-3 fatty acids exert antiinflammatory effects on patients with ulcerative colitis. However, a comparative study in patients with mild to moderate ulcerative colitis receiving only sulfasalazine or omega-3 fatty acids has not been performed. We sought to detect changes in the inflammatory disease activity with the use of either fish oil omega-3 fatty acids or sulfasalazine in patients with ulcerative colitis. Ten patients (five male, five female; mean age = 48 +/- 12 y) with mild to moderate active ulcerative colitis were investigated in a randomized cross-over design. They received either sulfasalazine (2 g/d) or omega-3 fatty acids (5.4 g/d) for 2 m.o. Disease activity was assessed by clinical and laboratory indicators, sigmoidoscopy, histology, and whole-body protein turnover (with 15N-glycine). Treatment with omega-3 fatty acids resulted in greater disease activity as detected by a significant increase in platelet count, erythrocyte sedimentation rate, C-reactive protein, and total fecal nitrogen excretion. No major changes in protein synthesis and breakdown were observed during either treatment. In conclusion, treatment with sulfasalazine is superior to treatment with omega-3 fatty acids in patients with mild to moderate active ulcerative colitis.

Biological differences between reflux stimulated proliferative stomal lesions and N-methyl-N'-nitro-N-nitrosoguanidine induced carcinomas in Wistar rats

The morphology and evolution of epithelial lesions that developed at a gastrojejunal stoma due to reflux of duodenal contents were compared with MNNG-induced carcinomas in the pyloric mucosa of rats in a long term experiment. Random bred male Wistar rats were given MNNG in drinking water (100 mg/l) for 12 weeks and then one group was submitted to a gastrojejunal anastomosis at the greater curvature in the oxyntic mucosa. Untreated rats underwent either gastrojejunostomy or gastrotomy. The animals were killed at the 24th and 66th weeks of the experiment. The lesions obtained in the pyloric mucosa and in the mucosa of the gastrojejunal stoma were analyzed histologically using hematoxylin and eosin staining and immunohistochemistry for pepsinogen isoenzyme 1. Duodenal reflux induced proliferative lesions at the gastrojejunal junction that increased in incidence and size with time. Histologically they consisted of benign epithelial proliferation of gastric type. No evidence of malignant transformation within the gastric components of the proliferative lesions at the gastrojejunal stoma was observed even at the 66th week. Adenocarcinomas induced by MNNG in the pyloric mucosa increased in size during the experiment and were morphologically and histochemically distinct from the proliferative lesions at the gastrojejunal junction. In conclusion, proliferative lesions at the gastrojejunal stoma stimulated by duodenal reflux are biologically distinct from adenocarcinomas induced by MNNG in the pyloric mucosa. They do not seem to be precursor lesions of gastric carcinogenesis, as they do not undergo malignant transformation even after long-term, up to 66 weeks, follow-up.

[Common iliac artery false aneurysm as complication of lumbar disc hernia surgery. Case report]

Surgery for discogenic disease of lumbar region is a challenging and diverse field. The significance of complications in disc surgery arises from the possibility that failure of primary treatment may lead to a permanently disable patient. The most common iatrogenic lesions in the posterior approach to lumbar disc herniation are neurologic, vascular, enteric, ureteral, and sexual dysfunction. Abramovitz reports that vascular complications of the posterior approach occur in at least 0.1% of cases. The vascular complications may present during surgery as severe bleeding leading to hypotension. The most common late complication is arteriovenous fistula followed by false aneurysms. We describe the case of a 39 year-old woman who was operated on for a lumbar disc herniation in other hospital. She came to us with a persistent pain in lumbar area. A MRI scan of lumbosacral region revealed a paravertebral lesion suggesting abscess. An angiography was performed and showed a false aneurysm of left common iliac artery, which was surgically treated successfully. We discuss the mechanisms of lesion and precautions against vascular ones during lumbar disc surgery.

Natural killer activity in a medium-term multi-organ bioassay for carcinogenesis

Natural killer (NK) cell activity was evaluated after the initiation and promotion steps in a medium-term multi-organ bioassay for carcinogenesis. NK cell activity was assessed in vitro by Cr51 release assay at the 4th and 30th weeks of the experiment. Male Wistar rats were sequentially initiated with N-diethylnitrosamine (DEN i.p.), N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN drinking water), N-methyl-N-nitrosourea (MNU i.p.), dihydroxy-di-N-propylnitrosamine (DHPN drinking water) and N,N'-dimethylhydrazine (DMH s.c.) at subcarcinogenic doses for 4 weeks (DMBDD initiation). One group was evaluated at the 4th week and the other was maintained without any further treatment until the 30th week. Two initiated groups were exposed through the diet to 2-acetylaminofluorene (2-AAF) or phenobarbital (PB), from the 6th until the 30th week. Five additional groups were studied to evaluate the effects of each initiator on NK activity. All groups submitted to initiation only, initiation plus promotion, or promotion only, developed significantly more preneoplastic lesions than the untreated control group. The main target organs for tumor development in the initiated animals were the liver and the colon, irrespective of treatment with 2-AAF or PB. NK cell activity was not affected by exposure to genotoxic carcinogens after initiation, at the 4th week. Treatments only with PB or 2-AAF did not change NK cell activity. However, decreased NK cell activity was registered in the group only initiated with DMBDD and in the group given DMBDD+2-AAF. This late depression of NK cell activity at the 30th week could be related to the production of suppressing molecules by the tumor cells.

[Use of proteic metabolism (15N-glycine) in the early detection of disease exacerbation in patients with non-specific ulcerative colitis]

Disease activity was assessed in 10 (five males and five females) ulcerative colitis patients through the following parameters: clinical, laboratory, sigmoidoscopic and histological. Protein metabolism was also assessed with 15N-glycine and urinary ammonia as end product. Only one patient had exacerbation of the disease two months after the study started. This patient presented in the beginning of the study protein synthesis and breakdown of 4.51 and 3.47 g protein/kg/day, respectively, values higher than all other patients, showing an hypermetabolic state, suggesting an increase of the disease activity. However, this increase was not detected by others indicators and indexes utilized. These data allow to suggest the hypothesis that protein metabolism predicts precociously the exacerbation of disease activity in ulcerative colitis patients.

[Disinfection of medical and surgical equipment: efficacy of chemical disinfectants and water and soap]

In this experimental study we compared the previous descontamination efficacy of the medical surgical materials by the use of chemical disinfectants and the mechanical cleaning with water and soap, as well as verified the organic material interference in these procedures. To carry out this study, we used surgical pincers under contamination with: Staphylococcus aureus ATCC-6538, Salmonella cholerae suis ATCC-10708, and Pseudomonas aeruginosa ATCC-15442 in presence and absence of organic matter (fetal bovine serum). The following treatments: glutaraldehyde 2%, sodium hypochlorite 1%, hydrogen peroxide 6%, alcohol 70% and the mechanical cleaning with water and soap were compared with eight repetitions in a total of 480 observations. In the described conditions, the disinfectants had a good efficacy in the previous descontamination of the medical surgical materials and a less inactivation by the organic material. The mechanical cleaning with water and soap showed a reduction of the microrganism to safe levels, considered adequate for previous descontamination.

Evaluation of the role of formulation on parathion toxicity

The influence of the vehicle on the toxicity of parathion was evaluated by determining the oral and dermal LD50 in rats. The assessment of dermal absorption was performed by measuring the inhibition of plasma cholinesterase activity. The test vehicles were arol and xylene. The data obtained indicated that the acute oral and dermal toxicities are higher in xylene than in arol, but no differences were observed on plasma cholinesterase activity.

Amitraz effects on foot-and-mouth disease virus in mammalian cells in vitro

The toxicity of the acaricide amitraz and its effect on foot-and-mouth disease virus multiplication were evaluated in IB-RS-2 cells in vitro. A reduction of cell growth rate that was dependent on the dose and the length of treatment was observed in cells exposed to amitraz concentrations ranging from 20 to 50 micrograms/ml. Foot-and-mouth disease virus infectivity remained essentially unchanged in cells exposed to amitraz (20 micrograms/ml) 24 hr prior to virus infection or after the adsorption period. Viral RNA synthesis evaluated through [3H]uridine incorporation in cells treated for 24 hr prior to infection was not affected by amitraz.

[Reactivation of ulcerative rectocolitis with the use of non-steroidal anti-inflammatory drugs. Report of a case and review of the literature]

The case of a patient with ulcerative colitis and isolated sacro-ileitis is presented. She suffered reactivation of the intestinal disease with diclofenac. The patient was allergic to sulfasalazine and was using fish oil fatty acid. The possible mechanisms of reactivation of the inflammatory bowel disease with non-steroidal anti-inflammatory drugs are discussed. It is suggested when necessary the utilization of non-steroidal anti-inflammatory drugs that inhibits the lipoxygenase in these patients.

Lactate dehydrogenase isoenzymes in mammalian cells exposed to isophenphos

The cytotoxicity of isophenphos, an organophosphorus insecticide that has the potential to cause delayed polyneuropathy, was evaluated in GBK and V79 cells. A 72 h time course following isophenphos exposure indicated a dose-dependent growth inhibition as determined by cell counts. The administration of isophenphos (20 g/ml) to GBK cells cultured at high densities indicated a decrease in the activities of LDH isoenzymes. Analysis of V79 cells revealed a decrease of LDH3, the only LDH isoenzyme detected in these cells.

Diabetes and experimental pregnancy in rats: course of maternal blood glucose levels and its repercussions on the blood glucose levels and pancreas of newborn pups

The objective of the present investigation was to determine the course of maternal blood glucose levels in pregnant rats and its repercussions on the glucose levels and pancreas of their newborn pups. Diabetes was induced by alloxan (42 mg/kg body weight) and streptozotocin (40 mg/kg). Sixty-two pregnant Wistar rats weighing 180 to 250 g were divided into a control group and two groups with moderate (120 to 200 mg/dl glucose) and severe diabetes (greater than 200 mg/dl glucose), respectively. Blood glucose levels were measured in the dams on the 1st, 14th, and 21st days of pregnancy and in the pups at birth. The results were pooled for each litter. The fetal pancreases were removed after cesarian section performed on the 21st day of pregnancy, pooled for each litter and processed for histopathologic examination by light microscopy. Maternal blood glucose levels were significantly increased compared with the first day of pregnancy in both normal and diabetic rats starting on the 14th day of pregnancy. Fetal blood glucose levels correlated with maternal levels. The histopathologic changes characterized by vacuolization and basophilia of the cytoplasm of endocrine pancreas of newborn pups from dams with moderate or severe diabetes suggested pancreatic hyperactivity.

Effects of ivermectin on the activity of enzymes in mammalian cells in vitro

The effects of ivermectin on the activities of lactate dehydrogenase, glucose-6-phosphate dehydrogenase, and glucose-6-phosphatase have been estimated in IB-RS-2 cells in vitro. A 72-hr time course following ivermectin exposure indicated a decrease in the activity of lactate dehydrogenase. The activities of glucose-6-phosphate dehydrogenase and glucose-6-phosphatase remained essentially unchanged.

Gut intraepithelial lymphocyte counts in neonates, infants and children

Intraepithelial lymphocyte (IEL) counts were histologically assessed in the jejunum, ileum and appendix of 39 neonates (0-28 days), 32 infants (1-9 months) and 13 children (1-9 years). Small intestinal mucosa samples were obtained from 73 autopsies, and from 8 surgical and 3 aspirative biopsies. IEL counts of specimens from the jejunum, ileum and appendix gave similar results in the same patient. The number of IEL counts was significantly lower in neonates for all three segments. The difference between infants and children was more marked in the jejunum than in the ileum, although this was not significant. In the appendix, there was no difference between the different age groups. Our results indicate that postnatal expansion of IEL occurs homogeneously along the gut after the neonatal period.

Gastric and small intestinal lesions after partial stomach resection with Billroth II or Roux-en-Y reconstruction in the rat

The evolution and phenotypic expression of mucosal lesions of the gastric stump were investigated in male rats submitted to gastric resection with reconstruction by the Billroth II technique (BII with biliopancreatic reflux, BPR) or by the Roux-en-Y procedure (without BPR). Animals were studied at 24, 36, 54 and 64 weeks after surgery and the phenotypic expression of lesions analysed using routine hematoxylin and eosin staining, immunohistochemical staining for pepsinogen isoenzyme 1 and histochemical procedures for mucins (paradoxical concanavalin A, galactose oxidase Schiff (GOS) and sialidase GOS reactions). BPR was found to be responsible for the formation of adenomatous hyperplasia (AH), increasing in incidence and size with time, since the Roux-en-Y procedure failed to induce the gastric stump lesions observed after BII reconstruction. AHs always occurred in the transition of the gastrojejunal junction, a site offering special conditions for BPR influence, and were classified as gastric (G), intestinal (I) and G+I types according to their phenotypic expression. No pure I type AH was diagnosed at any time point. The G and G+I types developed at approximately equal incidences (i.e., G type 7/17, G+I type 10/17 at the 64th week). It was suggested that both gastric and intestinal mucosal elements were stimulated to proliferate by BPR, with the gastric mucosa tending to demonstrate AH. Intestinal type components of AH were found adjacent to the jejunum and not at the stomach margin, indicating an origin from intestinal mucosa. No metaplasia of the gastric mucosa was observed in any animal after partial gastric resection. In 101 rats submitted to the BII procedure, 5 mucinous adenocarcinomas were eventually diagnosed, mostly located in the subserosa of the gastrojejunal junction. All carcinomas expressed the phenotype of cells of the small intestine. Evidence of malignant transformation within the gastric components of AH was not observed even at the 64th week. In conclusion, all lesions induced by BPR in the rat remnant stomach are benign, and the few true cancers that arise in association are derived from the small intestine.

Cytotoxicity of captafol in mammalian cells

The cytotoxicity of captafol, a phthalimide-derived fungicide, was evaluated in IB-RS-2 cells. Captafol at 0.12-1.0 microgram/ml blocks the cell multiplication. This effect is concentration-dependent, only partially reversible and the degree of inhibition increases with time. The synthesis of DNA and RNA is inhibited in parallel by increasing concentrations of the chemical.

[Lesions of the gastrointestinal tract in acquired immunodeficiency syndrome: study of 45 consecutive necropsies]

This study was designed to evaluate retrospectively the frequency and etiology of the gastrointestinal (GI) lesions in 45 consecutive necropsies of adult patients with Acquired Immunodeficiency Syndrome (AIDS). Gross descriptions and histological sections of the GI tract, from mouth to anus, were reviewed. The slides were H&E stained, and when necessary special stains and immunohistochemical methods were also employed. There were lesions in GI tract in 37 (82.3%) patients; the mouth was the segment most frequently involved (73.3% of the cases), followed by the colon (55.5%). Multiple lesions occurred in 17 (37.7%) cases. Cytomegalovirus caused colonic lesions in 35.7% of the cases. Candidiasis was observed in 26.6% mainly in the mouth and herpes simplex (8.8%) was the important agent of esophageal lesions. Oral hairy leukoplasia associated with HPV was found in 16 (35.5%) cases. Neoplasia was diagnosed in 7 (15.5%) cases: four Kaposi's sarcoma, two anal intramucosal carcinomas and one gastric lymphoma. Our data confirm the high frequency and variety of GI tract alterations in AIDS.

Effects of protein deficiency and natural intestinal infection with Giardia lamblia on jejunal intraepithelial lymphocytes in rats of different ages

1. The interaction between experimental protein deprivation and natural intestinal infection by Giardia lamblia was studied in terms of its effects on the intraepithelial lymphocyte (IEL) population and morphology of the jejunal mucosa of rats of different ages. 2. Young, adult and old male Wistar rats received a protein-deficient diet (2% casein) or a control diet (20% casein) for 42 days. Mucosal height and the number of lymphocytes located among 500 consecutive epithelial cells (EC) along the villi or crossing the basement membrane were determined in PAS-stained jejunal fragments. 3. The number of IEL increased progressively with animal age, from 14 to 25 per 100 epithelial cells, with significant differences between age ranges. However, the number of IEL did not differ between control and protein-deficient rats in any of the age groups. The proportion of lymphocytes crossing the basement membrane was approximately two-fold greater in young (2.8/100 EC) and adult (5.8/100 EC) protein-deficient animals than in their respective controls (1.6 and 2.8/100 EC). The intensity of parasite colonization was moderate, from 3 to 5/100 EC and did not differ between groups. The pattern of morphologic changes of jejunal mucosa in protozoal infection did not differ between control and protein-deficient animals in any of the three age groups. 4. We conclude that intestinal infection with Giardia lamblia probably stimulated the local immune response, masking the reduction of the IEL population induced by protein deficiency. The increase in lymphocyte numbers with age may be related to prolonged antigenic stimulation promoted by infection.

Acidic polysaccharides of the ascidian Styela plicata. Biosynthetic studies on the sulfated L-galactans of the tunic, and preliminary characterization of a dermatan sulfate-like polymer in body tissues

Histochemical and chemical analyses reveal important differences between tunic and body of the ascidian Styela plicata. The body contains hydroxyproline, nucleic acid and hexuronic acid. Analyses of the hexuronic acid-containing molecules indicates the presence of dermatan sulfate and heparan sulfate. The tunic, on the other hand, contains no hydroxyproline and small amounts of nucleic acid and hexuronic acid. Large amounts of sulfated polysaccharides, identified by agarose gel electrophoresis, are also present in the tunic. In vitro, incorporation of 35S-sulfate and 14C-glucose and 35S-sulfate pulse-chase experiments show that sulfate and glucose are incorporated into the sulfated polysaccharides of the tunic. The radioactivity is associated mainly with the region of the tunic containing the epidermal cells; however, a small amount of radioactivity is also detected in other regions of the tunic, suggesting that the sulfated polysaccharides are synthesized mainly by the epidermal cells and, to a small extent, by other cell types present in the tunic. Conversion of D-glucose to L-galactose, previously observed in the tunic of Styela plicata (Biochemistry 30, 3458-3464, 1990) is more intense in the region of the tunic containing the epidermal cells.

Assessment of gut intraepithelial lymphocytes during late gestation and the neonatal period

Intraepithelial lymphocyte counts (IEL % enterocytes) were carried out in histological samples of jejunal, ileal and appendiceal mucosa of 39 neonates, aged from birth to 28 days. Correlations between IEL counts and developmental factors, namely gestational age, birth weight and intrauterine growth, as well as neonatal infections or feeding state were performed. No significant differences were observed among neonates grouped according to birth weight, intrauterine growth or neonatal infections. The pattern of feeding, however was associated with significantly higher IEL counts (p < 0.02) in the ileum in oral/enterally fed neonates than in the unfed or parenterally fed. Full-term neonates also had higher counts in the ileum (p < 0.02). In this group, oral/enterally fed neonates had the higher values. Thus, besides in utero development, the pattern of feeding might be considered as an important modulating factor on IEL postnatal expansion.

Prevalence of Helicobacter pylori in Brazilian patients with gastric carcinoma

Investigators have speculated on the role of Helicobacter pylori in gastric carcinogenesis. The current study was performed to evaluate prospectively the prevalence of H. pylori infection in the stomachs of Brazilian patients with gastric carcinoma. Forty patients receiving gastrectomy for gastric carcinoma were studied. H. pylori was examined in four areas without atrophy or with minor atrophic changes. Mucosal fragments were obtained for microbiologic studies in 19 cases. H. pylori was detected in 82.5% of the cases. Of the cases evaluated by histologic and microbiologic methods, 94% had positive results by at least one method. In most cases there were small numbers of microorganisms. There was no correlation between the site and histologic type of neoplasia and the presence of H. pylori. The use of more than one diagnostic method improves H. pylori detection in gastric carcinoma. The small number of microorganisms observed in gastric carcinoma cases may lead to an underestimate of H. pylori in histologic sections. This might explain the variation in H. pylori infection rates reported for patients with gastric carcinoma.