Metal loads and biomarker suite responses in a tropical carnivorous fish indicative of anthropogenic impacts in a Southeastern Brazilian lagoon

Tropical coastal lagoons are highly productive environments exhibiting high biodiversity. However, the use of these ecosystems by local communities is of concern, since this generally leads to environmental degradation. The Imboassica coastal lagoon, located in Macaé city, in Northern Rio de Janeiro, is an important ecosystem in the state, however, already displaying signs of anthropogenic impacts. Carnivorous fish Hoplias malabaricus specimens were sampled from this impacted site, as well as from a reference area. Fish from Imboassica Lagoon presented lower condition factor, lower cholinesterase activity, and higher percentage of erythrocyte micronuclei when compared to fish from the reference site. Metals in fish from Imboassica Lagoon were always higher than Encantada Lagoon, with some seasonal differences, where some metals were higher in the rainy season compared to the dry season in muscle tissue, with the exception of Cu, Fe, Sr, and Zn; and in the liver, except for Ba, Cd, Cr, Ni, and Sr. Cr and Mn in the edible muscle portion of the fish were higher than the limits established by Brazilian and International legislations as permissible for human consumption, thus leading to concerns regarding public health risks for the local population that use fish as their main protein source.

Tumour-suppression function of KLF12 through regulation of anoikis

Suppression of detachment-induced cell death, known as anoikis, is an essential step for cancer metastasis to occur. We report here that expression of KLF12, a member of the Kruppel-like family of transcription factors, is downregulated in lung cancer cell lines that have been selected to grow in the absence of cell adhesion. Knockdown of KLF12 in parental cells results in decreased apoptosis following cell detachment from matrix. KLF12 regulates anoikis by promoting the cell cycle transition through S phase and therefore cell proliferation. Reduced expression levels of KLF12 results in increased ability of lung cancer cells to form tumours in vivo and is associated with poorer survival in lung cancer patients. We therefore identify KLF12 as a novel metastasis-suppressor gene whose loss of function is associated with anoikis resistance through control of the cell cycle.

The dark and bright sides of an enzyme: a three dimensional structure of the N-terminal domain of Zophobas morio luciferase-like enzyme, inferences on the biological function and origin of oxygenase/luciferase activity

Beetle luciferases, the enzymes responsible for bioluminescence, are special cases of CoA-ligases which have acquired a novel oxygenase activity, offering elegant models to investigate the structural origin of novel catalytic functions in enzymes. What the original function of their ancestors was, and how the new oxygenase function emerged leading to bioluminescence remains unclear. To address these questions, we solved the crystal structure of a recently cloned Malpighian luciferase-like enzyme of unknown function from Zophobas morio mealworms, which displays weak luminescence with ATP and the xenobiotic firefly d-luciferin. The three dimensional structure of the N-terminal domain showed the expected general fold of CoA-ligases, with a unique carboxylic substrate binding pocket, permitting the binding and CoA-thioesterification activity with a broad range of carboxylic substrates, including short-, medium-chain and aromatic acids, indicating a generalist function consistent with a xenobiotic-ligase. The thioesterification activity with l-luciferin, but not with the d-enantiomer, confirms that the oxygenase activity emerged from a stereoselective impediment of the thioesterification reaction with the latter, favoring the alternative chemiluminescence oxidative reaction. The structure and site-directed mutagenesis support the involvement of the main-chain amide carbonyl of the invariant glycine G323 as the catalytic base for luciferin C4 proton abstraction during the oxygenase activity in this enzyme and in beetle luciferases (G343).

SETD2 loss-of-function promotes renal cancer branched evolution through replication stress and impaired DNA repair

Defining mechanisms that generate intratumour heterogeneity and branched evolution may inspire novel therapeutic approaches to limit tumour diversity and adaptation. SETD2 (Su(var), Enhancer of zeste, Trithorax-domain containing 2) trimethylates histone-3 lysine-36 (H3K36me3) at sites of active transcription and is mutated in diverse tumour types, including clear cell renal carcinomas (ccRCCs). Distinct SETD2 mutations have been identified in spatially separated regions in ccRCC, indicative of intratumour heterogeneity. In this study, we have addressed the consequences of SETD2 loss-of-function through an integrated bioinformatics and functional genomics approach. We find that bi-allelic SETD2 aberrations are not associated with microsatellite instability in ccRCC. SETD2 depletion in ccRCC cells revealed aberrant and reduced nucleosome compaction and chromatin association of the key replication proteins minichromosome maintenance complex component (MCM7) and DNA polymerase δ hindering replication fork progression, and failure to load lens epithelium-derived growth factor and the Rad51 homologous recombination repair factor at DNA breaks. Consistent with these data, we observe chromosomal breakpoint locations are biased away from H3K36me3 sites in SETD2 wild-type ccRCCs relative to tumours with bi-allelic SETD2 aberrations and that H3K36me3-negative ccRCCs display elevated DNA damage in vivo. These data suggest a role for SETD2 in maintaining genome integrity through nucleosome stabilization, suppression of replication stress and the coordination of DNA repair.

Candida colonisation as a source for candidaemia

Candida spp. are important healthcare-associated pathogens. Identifying the source of infection is important for prevention and control strategies. The objective of this study was to evaluate candida colonisation sites as potential sources for candidaemia. Sixty-three consecutive patients with a positive blood culture for candida were included. Surveillance cultures were collected from urine, rectum, oropharynx, skin, intravascular catheter tip and skin around catheter. Molecular typing was performed when the same species of candida was isolated from blood and surveillance sites of a patient. C. albicans was associated with 42% of candidaemias, C. parapsilosis 33%, C. tropicalis 16% and C. guilliermondii, C. krusei, C. glabrata, C. holmii and C. metapsilosis were all 2% each. Six of 10 C. parapsilosis catheter tip isolates were indistinguishable from corresponding blood isolates (all in neonates). C. albicans isolates from blood were indistinguishable from corresponding gastrointestinal tract isolates in 13 of 26 patients and from catheter tip isolates in two patients. In conclusion, the results suggest that gastrointestinal colonisation is the probable source of C. albicans candidaemia and C. parapsilosis is exogenous.

Transthyretin interacts with metallothionein 2

Transthyretin (TTR) is a 55 kDa homotetrameric protein known for the transport of thyroxine and the indirect transportation of retinol. Within the central nervous system, TTR is primary synthesized and secreted into the cerebral spinal fluid by the choroid plexus (CP), whereas most TTR in the systemic circulation is produced and secreted by the liver. TTR is involved in two types of amyloid disease, the senile systemic amyloidosis and the familial amyloidotic polyneuropathy. TTR has also been implicated in the sequestration of amyloid beta peptide (Abeta), preventing its deposition. To explore other biological roles for TTR, we searched for protein-protein interactions using the yeast two-hybrid system with the full-length human TTR cDNA as bait. We found a novel interaction between TTR and metallothionein 2 (MT2) in human liver. This interaction was confirmed by competition binding assays, co-immunoprecipitation, cross-linking, and Western blotting experiments. Binding studies using MT1 showed a saturable specific interaction with TTR with a Kd of 244.8 +/- 44.1 nM. Western blotting experiments revealed a TTR-MT1/2 protein complex present in rat CP and kidney tissue extracts. Immunofluorescence experiments, in CP primary cell cultures and in CP paraffin sections, showed co-localization of TTR and MT1/2 in the cytoplasm of epithelial CP cells and localization of MT1/2 in the endoplasmic reticulum. Moreover, dot blot immunoassays of rat CSF provided the first evidence, to our knowledge, of circulating metallothionein in CSF. Taken together, we suggest that TTR-MT1/2 complexes may be functionally significant not only in healthy conditions but also in Abeta deposition in Alzheimer disease, thereby providing a novel potential therapeutic target.

Comparative performance of two air samplers for monitoring airborne fungal propagules

Many studies have attempted to evaluate the importance of airborne fungi in the development of invasive fungal infection, especially for immunocompromised hosts. Several kinds of instruments are available to quantitate fungal propagule levels in air. We compared the performance of the most frequently used air sampler, the Andersen sampler with six stages, with a portable one, the Reuter centrifugal sampler (RCS). A total of 84 samples were analyzed, 42 with each sampler. Twenty-eight different fungal genera were identified in samples analyzed with the Andersen instrument. In samples obtained with the RCS only seven different fungal genera were identified. The three most frequently isolated genera in samples analyzed with both devices were Penicillium, Aspergillus and Cladophialophora. In areas supplied with a high efficiency particulate air filter, fungal spore levels were usually lower when compared to areas without these filters. There was a significant correlation between total fungal propagule measurements taken with both devices on each sampling occasion (Pearson coefficient = 0.50). However, the Andersen device recovered a broader spectrum of fungi. We conclude that the RCS can be used for quantitative estimates of airborne microbiological concentrations. For qualitative studies, however, this device cannot be recommended.

Infections in a burn intensive care unit: experience of seven years

The objective of this study is to describe infections in a specialized burns intensive care unit from 1993 to 1999. The criteria for admission to the unit are: children with burns involving at least 10% or adults with burns involving at least 20% of total body surface; burns affecting face, perineum or feet; suspected or proven airway injury; electric or chemical burns; age less than one year or above 50; or pre-existing disease with any extent of burns. Surveillance of hospital-acquired infection was prospective. Hospital-acquired infection criteria used were those modified from the Centers for Disease Control and Prevention. Diagnosis of infection using skin biopsy was not done. Over the study period, 320 patients were admitted to our burns intensive care unit. One hundred and seventy-five (55%) developed 388 hospital-acquired infections. The rate for vascular catheter-associated bloodstream infections was 34 per 1,000 central line-days. The rate of ventilator associated pneumonia was 26 infections per 1,000 ventilator-days. Primary bloodstream was the most common infection with 189 episodes (49%); followed by 83 burn wound infections (21%) and 56 pneumonias (14%). In 76% of these infections and in 97% of the primary bloodstream infections, aetiological agents were identified. The micro-organisms causing infections were S taphylococcus aureus (24%), Pseudomonas aeruginosa (18%), Acinetobacter spp. (14%) and coagulase-negative staphylococci (12%). Candida spp. caused 8% of infections. Gram-positive and Gram-negative organisms exhibited resistance to most antimicrobial agents used for therapy. During the first three days of hospitalization in the burns intensive care unit there were eight infections caused by S. aureus and three of these were resistant to oxacillin. These data provide background information regarding extensive burn patients on which decisions for control and prevention of hospital-acquired infections can be made.

Nosocomial pneumonia: importance of recognition of aetiological agents to define an appropriate initial empirical therapy

Of the 16,024 patients hospitalized from January 1995 to October 1997, 397 (2.4%) acquired nosocomial pneumonia and the aetiological agent was defined in 101 (25%). About 82% developed late onset pneumonia (>7 days of hospitalization). The site of isolation of microorganisms was bronchoalveolar lavage (BAL) (49%), blood culture (39%), pleural effusion (10%) and (2%) pulmonary tissue. Gram-negative bacteria were responsible for 54% of infections. Staphylococcus aureus (34%) was the most frequent microorganism isolated followed by Acinetobacter baumannii (29%) and Pseudomonas aeruginosa and Klebsiella pneumoniae, responsible for 7% of nosocomial pneumonia. Monotherapy gave good cover for early onset pneumonia, but not for late onset pneumonia. Based on our selection criteria, ciprofloxacin was the best monotherapy for early (50%) and late (31%) onset pneumonia. Vancomycin plus ciprofloxacin gave cover of 85% of early and 64% of late onset pneumonia. Monotherapy with ciprofloxacin and also combination therapy of ciprofloxacin plus vancomycin may be good options as initial empirical therapy for nosocomial pneumonia.

Cloning, characterization, and tissue distribution of prolactin receptor in the sea bream (Sparus aurata)

The prolactin receptor (PRLR) was cloned and its tissue distribution characterized in adults of the protandrous hermaphrodite marine teleost, the sea bream (Sparus aurata). An homologous cDNA probe for sea bream PRLR (sbPRLR) was obtained by RT-PCR using gill mRNA. This probe was used to screen intestine and kidney cDNA libraries from which two overlapping clones (1100 and 2425 bp, respectively) were obtained. These clones had 100% sequence identity in the overlapping region (893 bp) and were used to deduce the complete amino acid sequence of sbPRLR. The receptor spans 2640 bp and encodes a protein of 537 amino acids. Features characteristic of PRLR, two pairs of cysteines, WS box, hydrophobic transmembrane domain, box 1, and box 2, were identified and showed a high degree of sequence identity to PRLRs from other vertebrate species. SbPRLR is 29 and 32% identical to tilapia (Oreochromis niloticus) and goldfish (Carassius auratus) PRLRs, respectively. In the sea bream two PRLR transcripts of 2.8 and 3.2 kb were detected in the intestine, kidney, and gills and a single transcript of 2.8 kb was detected in skin and pituitary by Northern blot. Spermiating gonads (more than 95% male tissue; gonado-somatic index of 0.6) contained, in addition to the 2.8-kb transcript, three more transcripts of 1.9, 1.3, and 1.1 kb. RT-PCR, which is a far more sensitive method than Northern blot, detected PRLR mRNA in gills, intestine, brain, pituitary, kidney, liver, gonads, spleen, head-kidney, heart, muscle, and bone. Immunohistochemistry using specific polyclonal antibodies raised against an oligopeptide from the extracellular domain of sbPRLR detected PRLR in several epithelial tissues of juvenile sea bream, including the anterior gut, renal tubule, choroid membrane of the third ventricle, saccus vasculosus, branchial chloride cells, and branchial cartilage.

Evolution of the thyroid hormone-binding protein, transthyretin

Transthyretin (TTR) belongs to a group of proteins, which includes thyroxine-binding globulin and albumin, that bind to and transport thyroid hormones in the blood. TTR is also indirectly implicated in the carriage of vitamin A through the mediation of retinol-binding protein (RBP). It was first identified in 1942 in human serum and cerebrospinal fluid and was formerly called prealbumin for its ability to migrate faster than serum albumin on electrophoresis of whole plasma. It is a single polypeptide chain of 127 amino acids (14,000 Da) and is present in the plasma as a tetramer of noncovalently bound monomers. The major sites of synthesis of TTR in eutherian mammals, marsupials, and birds are the liver and choroid plexus but in reptiles it is synthesised only in the choroid plexus. The observation that TTR is strongly expressed in the choroid plexus but not in the liver of the stumpy-tailed lizard and the strong conservation of expression in the choroid plexus from reptiles to mammals have been taken as evidence to suggest that extrahepatic synthesis of TTR evolved first. The identification and cloning of TTR from the liver of an amphibian, Rana catesbeiana, and a teleost fish, Sparus aurata, and its absence from the choroid plexus of both species suggest an alternative model for its evolution. Protein modelling studies are presented that demonstrate differences in the electrostatic characteristics of the molecule in human, rat, chicken, and fish, which may explain why, in contrast to TTR from human and rat, TTR from fish and birds preferentially binds triiodo-l-thyronine.

Survival and functional results of Pearson's near-total laryngectomy for larynx and pyriform sinus carcinoma

BACKGROUND

Current treatment for most T3 and T4 transglottic and pyriform sinus carcinomas is total laryngectomy or total laryngectomy with partial pharyngectomy. Voice rehabilitation usually requires the use of a tracheoesophageal puncture (TEP). Pearson's near-total laryngectomy (NTL) is an option for voice preservation in selected cases with no invasion of the interarythenoid space and limited invasion of the subglottis. The purpose of this study is to report the functional and survival results of 42 consecutive patients who underwent NTL from 1988 to 1995. Patients and Methods The patients were 40 men and two women, with a median age of 58 years. All patients had squamous cell carcinoma. There were 37 larynx and five pyriform sinus tumors. T3 stage tumor represented 85.7% of the cases.

RESULTS

There were complications in 13 patients (28.9%). Vocal quality was considered good in 83.3% of the cases. To date, eight patients presented tumor recurrences: two local, two in the neck, and four distant. The 5-year actuarial overall survival rates were of 81.7% in larynx carcinoma and 66.6% in pyriform sinus carcinoma.

CONCLUSIONS

In selected transglottic and pyriform sinus carcinomas, NTL can be carried out with acceptable morbidity and a high potential of voice preservation and tumor control.

Identification of transthyretin in fish (Sparus aurata): cDNA cloning and characterisation

Transthyretin (TTR) has been proposed to have first evolved in reptiles and is one of the three plasma proteins important in the transport of thyroid hormones in higher vertebrates. A full-length cDNA encoding TTR was isolated from a sea bream (Sparus aurata) liver cDNA library using a homologous TTR cDNA probe generated by RT-PCR. Comparison of the deduced amino acid sequence of sea bream TTR with other published sequences, revealed an overall identity of 47-54%, although the amino acids in the active binding site were almost 100% conserved. Distribution of TTR was studied in sea bream adult tissue by RT-PCR and was detected in liver, brain, pituitary, gills, kidney, intestine and testis, although northern blot analysis only revealed TTR in the liver, suggesting that in sea bream, liver is the main source of this protein. TTR was also expressed in larvae from the first day post-hatch (48 h post-fertilisation). Analysis of thyroxine (T4) and triiodo-L-thyronine (T3) binding to sea bream serum proteins demonstrated that both T4 and T3 bind to albumin and TTR. By demonstrating the existence of TTR in teleost fish this study indicates TTR must have evolved in a common fish ancestor of the tetrapod evolutionary line.

Cloning, expression, and tissue localisation of prolactin in adult sea bream (Sparus aurata)

A major action of prolactin (PRL) in teleost fish is the maintenance of hydromineral balance in euryhaline species in fresh water. The function of PRL in marine teleosts is less certain and unlike euryhaline teleosts, such as tilapia and salmon, there is relatively little information about protein or gene structure. Associated with studies to determine potential functions of PRL, pituitary prolactin cDNA has been cloned and sequenced from sea bream (Sparus aurata), a marine teleost. The sequence obtained spanned 1349 bp and contained an open reading frame encoding a protein of 212 amino acids composed of a putative signal peptide of 24 residues and a mature protein of 188 amino acids. N-terminal sequencing of the native protein confirmed unambiguously the cleavage site, Ala24, Val25, predicted from alignments of the sea bream PRL cDNA with that of other teleosts. The presence of only one form of PRL in sea bream was supported by identification using Northern blots of only a single transcript of 1.35 kb. Reverse transcription and polymerase chain reaction techniques coupled with Southern blot analysis resulted in the detection of PRL in the pituitary but also in the intestine, liver, ovary, and testes.

Prognostic factors in supraglottic carcinoma patients treated by surgery or radiotherapy

The decision regarding treatment of supraglottic carcinoma remains controversial, despite recent advances in radiotherapy and surgical procedures. The need to evaluate the prognostic importance of demographic, clinical, pathologic, and treatment-related variables prompted this study. The patient population was of 164 consecutive cases of supraglottic carcinoma. Clinical charts were reviewed and cases were restaged according to the 1987 version of the UICC-AJC classification based on the initial clinical description: 18 T1, 30 T2, 58 T3, 58 T4, 61 NO, 24 N1, and 79 N2a-N3. Management policy for these patients varied during the study, reflecting different opinions of the responsible physicians and technical advances. Seventy-seven patients (47%) underwent surgery, patients who underwent surgery and radiotherapy, respectively, remained alive with no evidence of disease. The 5-year actuarial survival rates were 58.5% for patients initially treated by surgery, and 16.3% for patients in the radiotherapy group. Although several demographic, clinical, and pathologic variables were studied, only initial treatment (p <.0001), N stage (p = .0003), and T stage (p = .0017) were deemed to have independent prognostic value by multivariate regression techniques based on Cox's proportional hazards model. This study has shown that survival of supraglottic carcinoma patients depends on the treatment modality, T stage, and N stage. Our results are disappointing with regard to radiotherapy as a treatment for supraglottic carcinoma in patients with tumors at clinical stages III and IV.

Cloning and sequencing of a full-length sea bream (Sparus aurata) beta-actin cDNA

A full-length cDNA clone encoding beta-actin (beta-actin) was isolated from a sea bream (Sparus aurata) liver cDNA library. Sequencing of this clone reveals an open reading frame encoding a 375 amino acid protein that shares a high degree of conservation to other known actins. The sea bream beta-actin sequence showed 98% identity to carp and human beta-actin and 95% and 94% identity to sea squirt and Dictyostelium cytoplasmic actins, respectively.

Prognostic factors in T3,N0-1 glottic and transglottic carcinoma. A multifactorial study of 221 cases treated by surgery or radiotherapy

OBJECTIVE

To evaluate prognostic factors in patients with T3,N0-1 glottic and transglottic carcinoma treated in a single institution.

DESIGN

Retrospective, nonrandomized case series.

SETTING

Tertiary case referral centers, ambulatory or hospitalized care.

PATIENTS

Two hundred twenty-one consecutive cases of stage III glottic or transglottic squamous cell carcinoma. Tumor stage was T3,N0,M0 in 167 cases and T3,N1,M0 in 54 cases.

INTERVENTIONS

Surgery in 176 cases and radiotherapy in 45 cases.

MAIN OUTCOME MEASURES

Recurrences and survival (multivariate).

RESULTS

Almost 7% of the patients who underwent surgery and 39.6% who had radiotherapy had local recurrences. Recurrences in the neck were seen in 16.4% of the patients who underwent surgery and in 10.5% of those who had radiotherapy. Distant metastases were diagnosed only in patients who underwent surgery (4.6%). The 5-year actuarial overall survival rates were 56.3% in the surgical group and 35.2% in the radiotherapy group (P = .007). Age involvement of pyriform sinus, N stage, and history of tracheostomy were independent prognostic factors for risk of death.

CONCLUSIONS

The presence of metastatic lymph nodes, age, and involvement of the pyriform sinus were the important prognostic factors in patients who underwent surgery. A small group of patients with T3,N0,M0 tumors could benefit from radiotherapy, with surgery reserved for recurrence.

Factors influencing contralateral metastasis and prognosis from pyriform sinus carcinoma

BACKGROUND

The presence of neck metastasis reduces the probability of regional control and survival. The purpose of this study is to identify risk factors for contralateral neck metastasis in a series of 218 patients with pyriform sinus carcinoma.

PATIENTS AND METHODS

Tumor stages were: 31 T1-T2, 187 T3-T4, 40 N0, 174 N1-N3, and 4 NX. A total of 182 patients (83%) had metastatic lymph nodes (23 in the contralateral neck).

RESULTS

Thirty-five patients presented neck recurrences (27 in contralateral undissected neck). Logistic regression identified T and N stages, epilarynx and posterior pharyngeal wall involvement, hemilarynx fixation, and ipsilateral level 1 metastasis as important predictors of contralateral metastasis. Five-year survival rates were 41% (pN0), 23% (contralateral pN0), and 31% (contralateral positive nodes).

CONCLUSIONS

The contralateral side of the neck was the most common site of recurrence. A lateral neck dissection is advisable for the contralateral side of the neck for high-risk patients.

Cloning and characterisation of a fish aldolase B gene

A full length cDNA clone representing an aldolase mRNA was isolated from a sea bream (Sparus aurata) liver cDNA library. Sequencing of this clone revealed it to encode a 364 amino acid protein with 74% amino acid identity to human aldolase B and slightly lower similarity to human aldolase A and C. In view of the sequence data and of Northern blot analysis showing strong expression of a 1.6 kb transcript in liver it was concluded that the cloned gene represents aldolase B. This clone represents the first aldolase gene to be sequenced from any fish species thus providing new data on the evolution of the vertebrate aldolase gene family.

Prognostic factors in glottic carcinoma clinical stage I and II treated by surgery or radiotherapy

INTRODUCTION

Decision making regarding selection of treatment for early glottic carcinoma remains controversial. This study was undertaken to assess the impact of such factors as patient age, stage of tumor, site and size of characteristic of the lesion, and other characteristics relative to disease free and overall survival rates.

PATIENTS AND METHODS

The records of 145 consecutive patients with stage I and II glottic carcinomas treated between 1954 and 1990 were reviewed retrospectively. Surgery was performed on 50 patients (34.5%), and irradiation therapy was performed on 95 (65.5%). Cox's regression model was used to estimate the hazard ratios of recurrence and death.

RESULTS

Median follow-up was 69.3 months. Death due to cancer or treatment complications occurred in 29 patients, whereas 25 patients died due to causes not related to cancer. Five-year rates for overall survival and disease-free intervals were 94.6% and 70.8%, respectively. Tumor control was achieved by initial surgery or irradiation in 78% and 69.5%, respectively. T stage and vocal cord mobility in this series were not associated with prognosis. Arytenoid involvement intended to indicate a worse prognosis. Other site involvement such as anterior commissure had no prognostic impact.

DISCUSSION

Although stage I and II glottic cancers represent a heterogenous group, survival rates after surgery or radiotherapy vary relatively little. Death due to occurred in 17.9% of patients included in this series, whereas 17.2% died due to causes not related to cancer. Local recurrence following irradiation (29.5%) occurred more frequently than following surgery (10%). The choice of treatment modality for stage I and II glottic cancer should be justified by patient preference, involvement of anterior commissure, and impairment of vocal cord mobility and should not be a contraindication to radiotherapy.

Clinical characteristics of acute myocardial infarction in patients with Chagas' disease

From 1981 to 1988, 404 patients at our institution were found to have acute myocardial infarction. Of them, 18 (4%) had a positive fixation test for Chagas' disease. Patient age ranged from 41 to 80 years (median = 59). Eleven patients were males. Eighteen nonchagasic patients were matched by 2 year age intervals and sex with each chagasic patient. Before acute myocardial infarction, there were no differences between chagasic and nonchagasic patients with regard to the proportion of stable angina, unstable angina and coronary risk factors. Atypical chest pain occurred in 8 of 15 (53%) chagasic patients for whom this information was found in the medical records and in 1 of 18 (5%) nonchagasic patients (p = 0.003); dyspnea and palpitations occurred in 6 of 15 (40%) chagasic and 1 of 17 (5%) nonchagasic patients (p = 0.025). There were no differences between chagasic and nonchagasic patients with respect to both clinical characteristics and cardiac complications of acute myocardial infarction. Nonetheless, 4 of 11 (36%) chagasic patients for whom this information was listed in the medical records but none of 16 nonchagasic patients had normal coronary arteries (p = 0.019). Thus, chagasic patients who develop acute myocardial infarction have some peculiarities both in the clinical profile before the acute event and in the anatomy of the coronary arteries.

Clinical profile of patients with Chagas' disease before and during sustained ventricular tachycardia

Sustained ventricular tachycardia was diagnosed in 15 patients undergoing ordinary activity with Chagas' disease seen at our Institute from 1978 to 1989. Palpitations were observed in 11 (66%) of the patients, dyspnea in 7 (46%), atypical chest pain in 5 (33%) and syncope in 2 (13%). Cardiac arrhythmia was detected in 4 (26%) on physical examination. The resting electrocardiogram showed premature ventricular contractions in 13 (86%) patients, ST-T changes in 12 (80%), left axis deviation in 9 (60%) and right bundle branch block in 4 (26%). Chest X-rays showed mild cardiomegaly in 8 (53%) and moderate cardiomegaly in 3 (20%) patients. Mild left ventricular dysfunction was detected echocardiographically in 1 (10%), moderate in 3 (30%) and severe in 1 (10%) of the 10 patients studied. During sustained ventricular tachycardia, dyspnea was found in 7 of 15 (46%) patients, palpitations in 6 (40%), atypical chest pain in 6 (40%), syncope in 1 (6%), systemic arterial hypotension in 3 (20%) and cardiogenic shock in 2 (13%). The electrocardiographic findings were as follows: mean heart rate was 201 bpm; mean QRS lengthening was 0.16 sec; right bundle branch block plus right axis deviation was seen in 5 of 15 (33%) patients; right bundle branch block plus left axis deviation in 4 (26%); and a positive concordance of all precordial leads in 5 (33%) patients. Based on these findings, we conclude that the majority of patients with Chagas' disease who develop sustained ventricular tachycardia do not have severe myocardial disease, show an uncommon electrocardiographic pattern of this arrhythmia, and most importantly, have a benign clinical course.

Herpetic corneal ulcer following radial keratotomy

This is a report of a 30-year-old woman who had a herpetic corneal ulcer following radial keratotomy. Clinical applications of the results of this case reveal the following questions. (1) Can antiviral metabolites be used to prevent corneal scars, especially in the visual axis? (2) Should radial keratotomy be avoided during the vulnerable menstrual cycle period of females to prevent possible triggering of a herpetic ulcer regardless of previous herpes history?

[Human serum hexosamine. Determination in neoplastic disease (author's transl)]

The serum hexosamine levels of 93 patients with neoplastic disease and of 30 normal individuals chosen among medical students were determined. The mean values obtained in both groups show that in neoplastic disease the levels are higher than in normal persons. The application of Student (/t/) indicates a significant differences in the mean values (/t/) = 6.93 P less than 0.001). It is concluded that serum hexosamine contents are elevated in neoplastic disease.