Analysis of myocardial salvage with cardiac magnetic ressonance and angiography depending on the STEMI revascularization pathway in a PPCI centre

Background

Reperfusion networks have permitted improvements in reperfusion delays in primary percutaneous coronary intervention (PPCI)-treated ST elevation myocardial infarction (STEMI). However, the impact on myocardial salvage (MS) of direct transfer to the catheterization laboratory (cath-lab) to minimize system delay remains unknown.

Objective

We sought to quantify the myocardial salvage index (MSI) acutely and to assess adverse remodeling at 6 months in PPCI-treated STEMI according to the mode of patient presentation.

Methods

Between 2005 and 2021 we included 493 patients in a single center registry of first PPCI-treated STEMI who were studied with Late gadolinium enhanced (LGE) cardiac magnetic resonance (CMR) in the acute phase. Among them, 414 (84.0%) underwent a second LGE-CMR at 6 months. Subjects were classified depending on the mode of presentation: those diagnosed out-of-hospital and directly transferred to the cath-lab by the Emergency Medical Services (EMS group, 29.82%); subjects with first medical contact in a PCI-capable hospital (PCI-H group, 41.75%); and patients presenting to a non-PCI-capable center and transferred for PCI (non-PCI-H group, 28.43%). We computed the angiographic area at risk by BARI score, and combined it with the LGE-CMR derived infarct size to compute a validated MSI, expressed as percentage of area at risk. The change in ejection fraction (EF) and indexed left ventricle end-diastolic volume (iLVEDV) from baseline to 6 months was also computed.

Results

The mean age was 58.9±11.9 years, 84.5% were male and 51.4% had anterior STEMI. Total median ischaemic time was (median (interquartile range)) 126 (105–161) min in the EMS group, 201 (145–321) min in the PCI-H group and 300 (173–592) min in the non-PCI-H group (p<0.01). MSI was 45.28±2.6%, 39.63±2.2% and 35.53±2.7% respectively (p=0.034). In a multiple linear regression model adjusting for relevant covariables, including initial TIMI flow, area at risk, Killip class, age, sex, diabetes, number of vessels and presence of collaterals, a 7.50% (95% CI 0.9 to 14.1%) increase in MSI was observed in the EMS group compared to the PCI-H group, and 11.03% (95% CI 3.9 to 18.2%) compared to the non-PCI-H group (p=0.027 and 0.003 respectively). At 6 months, the mean absolute increase in EF was 5.36±0.6% for the EMS group, 4.03±0.5% for the PCI-H group and 3.52±0.6% for the non-PCI-H group (p<0.05 in the adjusted analysis) and the increase in iLVEDV was 2.37±7.3, 5.51±6.6 and 18.30±7.6 mL/m2 respectively (p=0.28).

Conclusions

Patients with out-of-hospital diagnostis of STEMI by the EMS who were directly transferred to the cath-lab showed shorter total ischaemic times, resulting in increased myocardial salvage and a trend towards improved indexes of left ventricular function at 6 months.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Grant from La Maratό de TV3 and grant from Fundaciό La Caixa

Combination of white matter hyperintensities and Aβ burden is related to cognitive composites domain scores in subjective cognitive decline: the FACEHBI cohort

BACKGROUND

To explore whether the combination of white matter hyperintensities (WMHs) and amyloid-beta (Aβ) deposition is associated with worse cognitive performance on cognitive composites (CCs) domain scores in individuals with subjective cognitive decline (SCD).

METHODS

Two hundred participants from the FACEHBI cohort underwent structural magnetic resonance imaging (MRI), 18F-florbetaben positron emission tomography (FBB-PET), and neuropsychological assessment. WMHs were addressed through the Fazekas scale, the Age-Related White Matter Changes (ARWMC) scale, and the FreeSurfer pipeline. Eight CCs domain scores were created using the principal component analysis (PCA). Age, sex, education, and apolipoprotein E (APOE) were used as adjusting variables.

RESULTS

Adjusted multiple linear regression models showed that FreeSurfer (B - .245; 95% CI - .1.676, - .393, p = .016) and β burden (SUVR) (B - .180; 95% CI - 2.140, - .292; p = .070) were associated with face-name associative memory CCs domain score, although the latest one was not statistically significant after correction for multiple testing (p = .070). There was non-significant interaction of these two factors on this same CCs domain score (p = .54). However, its cumulative effects on face-name associative performance indicated that those individuals with either higher WMH load or higher Aβ burden showed the worst performance on the face-name associative memory CCs domain score.

CONCLUSIONS

Our results suggest that increased WMH load and increased Aβ are independently associated with poorer episodic memory performance in SCD individuals, indicating a cumulative effect of the combination of these two pathological conditions in promoting lower cognitive performance, an aspect that could help in terms of treatment and prevention.

The role of radioactive iodine in the management of patients with differentiated thyroid cancer - An oncologic surgical perspective

With improved understanding of the biology of differentiated thyroid carcinoma its management is evolving. The approach to surgery for the primary tumour and elective nodal surgery is moving from a "one-size-fits-all" recommendation to a more personalised approach based on risk group stratification. With this selective approach to initial surgery, the indications for adjuvant radioactive iodine (RAI) therapy are also changing. This selective approach to adjuvant therapy requires understanding by the entire treatment team of the rationale for RAI, the potential for benefit, the limitations of the evidence, and the potential for side-effects. This review considers the evidence base for the benefits of using RAI in the primary and recurrent setting as well as the side-effects and risks from RAI treatment. By considering the pros and cons of adjuvant therapy we present an oncologic surgical perspective on selection of treatment for patients, both following pre-operative diagnostic biopsy and in the setting of a post-operative diagnosis of malignancy.

Meta-analysis of routine calcium/vitamin D3 supplementation versus serum calcium level-based strategy to prevent postoperative hypocalcaemia after thyroidectomy

BACKGROUND

The aim was to assess the effectiveness of routine administration of calcium +/- vitamin D3 compared with a serum calcium level-based strategy to prevent symptomatic hypocalcaemia after thyroidectomy.

METHODS

RCTs comparing routine supplementation of calcium +/- vitamin D3 with treatment based on serum calcium levels measured after total thyroidectomy, published between 1980 and 2017, were identified in MEDLINE, Embase, LILACS and Google Scholar databases. Risk of bias was evaluated using the Cochrane Collaboration tool. Risk differences were calculated by random-effects meta-analysis. Meta-regression and cumulative meta-analysis were used to explore the best therapeutic approach.

RESULTS

Fifteen studies with 3037 patients were included, and seven treatment comparisons were made. Routine supplementation with calcium + vitamin D3 offered a lower risk of symptomatic (risk difference (RD) -0·25, 95 per cent c.i. -0·32 to -0·18) and biochemical (RD -0·24, -0·31 to -0·17) hypocalcaemia than treatment based on measurement of calcium levels. The number needed to treat was 4 (95 per cent c.i. 3 to 6) for symptomatic hypocalcaemia. No publication bias was found; although heterogeneity was high for some comparisons, sensitivity analysis did not change the main results.

CONCLUSION

Routine postoperative administration of calcium + vitamin D3 is effective in decreasing the rate of symptomatic and biochemical hypocalcaemia.

The role of laryngectomy in locally advanced thyroid carcinoma. Review of 16 cases

SUMMARY

Locally advanced disease with larynx invasion is a challenge to the surgeon, but laryngectomy is almost never necessary in thyroid carcinoma. The aim of this study was to review the clinical outcomes of patients with locally advanced thyroid carcinoma invading the larynx who underwent laryngectomy. A case series of patients treated in a tertiary care hospital was reviewed. Data about the type of operation, method of reconstruction, complications and overall survival of 16 patients operated on between 2002 and 2015 with larynx invasion is presented. There were 10 females. The mean age was 63 ± 8.8 years. Besides total thyroidectomy and neck dissection, four patients underwent total pharyngolaryngectomy, 11 total laryngectomy and one hemi-laryngectomy. Reconstruction was made with regional flaps in 10 patients (7 pectoral/Bakamjian flaps and 3 gastric pull-through procedures) and a jejunum free flap in one patient. Two patients needed carotid artery reconstruction. Five tumours were classic (conventional) papillary carcinoma variants, while the others were aggressive histological varieties (insular, tall cell, sclerosing). The mean tumour size was 4.3 ± 1.6 cm. All tumours had lymphovascular invasion and 12 had positive lymph nodes. Concomitantly, oesophageal/hypopharyngeal invasion was present in 7 cases and invasion of carotid vessels in 2 cases. There were two postoperative deaths and two anastomotic leaks that were treated conservatively. The mean overall survival was 31 ± 33 months (median 27.6 months, range 0-120). Laryngectomy is an alternative surgical procedure to control selected cases of advanced thyroid carcinoma that offers good local control and long term survival.

Correlations between plasma and PET beta-amyloid levels in individuals with subjective cognitive decline: the Fundació ACE Healthy Brain Initiative (FACEHBI)

BACKGROUND

Peripheral biomarkers that identify individuals at risk of developing Alzheimer's disease (AD) or predicting high amyloid beta (Aβ) brain burden would be highly valuable. To facilitate clinical trials of disease-modifying therapies, plasma concentrations of Aβ species are good candidates for peripheral AD biomarkers, but studies to date have generated conflicting results.

METHODS

The Fundació ACE Healthy Brain Initiative (FACEHBI) study uses a convenience sample of 200 individuals diagnosed with subjective cognitive decline (SCD) at the Fundació ACE (Barcelona, Spain) who underwent amyloid florbetaben(18F) (FBB) positron emission tomography (PET) brain imaging. Baseline plasma samples from FACEHBI subjects (aged 65.9 ± 7.2 years) were analyzed using the ABtest (Araclon Biotech). This test directly determines the free plasma (FP) and total plasma (TP) levels of Aβ40 and Aβ42 peptides. The association between Aβ40 and Aβ42 plasma levels and FBB-PET global standardized uptake value ratio (SUVR) was determined using correlations and linear regression-based methods. The effect of the APOE genotype on plasma Aβ levels and FBB-PET was also assessed. Finally, various models including different combinations of demographics, genetics, and Aβ plasma levels were constructed using logistic regression and area under the receiver operating characteristic curve (AUROC) analyses to evaluate their ability for discriminating which subjects presented brain amyloidosis.

RESULTS

FBB-PET global SUVR correlated weakly but significantly with Aβ42/40 plasma ratios. For TP42/40, this observation persisted after controlling for age and APOE ε4 allele carrier status (R2 = 0.193, p = 1.01E-09). The ROC curve demonstrated that plasma Aβ measurements are not superior to APOE and age in combination in predicting brain amyloidosis. It is noteworthy that using a simple preselection tool (the TP42/40 ratio with an empirical cut-off value of 0.08) optimizes the sensitivity and reduces the number of individuals subjected to Aβ FBB-PET scanners to 52.8%. No significant dependency was observed between APOE genotype and plasma Aβ measurements (p value for interaction = 0.105).

CONCLUSION

Brain and plasma Aβ levels are partially correlated in individuals diagnosed with SCD. Aβ plasma measurements, particularly the TP42/40 ratio, could generate a new recruitment strategy independent of the APOE genotype that would improve identification of SCD subjects with brain amyloidosis and reduce the rate of screening failures in preclinical AD studies. Independent replication of these findings is warranted.

FACEHBI: A Prospective Study of Risk Factors, Biomarkers and Cognition in a Cohort of Individuals with Subjective Cognitive Decline. Study Rationale and Research Protocols

BACKGROUND

Long-term longitudinal studies with multimodal biomarkers are needed to delve into the knowledge of preclinical AD. Subjective cognitive decline has been proposed as a risk factor for the development of cognitive impairment. Thus, including individuals with SCD in observational studies may be a cost-effective strategy to increase the prevalence of preclinical AD in the sample.

OBJECTIVES

To describe the rationale, research protocols and baseline characteristics of participants in the Fundació ACE Healthy Brain Initiative (FACEHBI).

DESIGN

FACEHBI is a clinical trial (EudraCT: 2014-000798-38) embedded within a long-term observational study of individuals with SCD.

SETTING

Participants have been recruited at the memory clinic of Fundació ACE (Barcelona) from two different sources: patients referred by a general practitioner and individuals from an Open House Initiative.

PARTICIPANTS

200 individuals diagnosed with SCD with a strictly normal performance in a comprehensive neuropsychological battery.

MEASUREMENTS

Individuals will undergo an extensive neuropsychological protocol, risk factor assessment and a set of multimodal biomarkers including florbetaben PET, structural and functional MRI, diffusion tensor imaging, determination of amyloid species in plasma and neurophthalmologic assessment with optical coherence tomography.

RESULTS

Two hundred individuals have been recruited in 15 months. Mean age was 65.9 years; mean MMSE was 29.2 with a mean of 14.8 years of education.

CONCLUSIONS

FACEHBI is a long-term study of cognition, biomarkers and lifestyle that has been designed upon an innovative symptom-based approach using SCD as target population. It will shed light on the pathophysiology of preclinical AD and the role of SCD as a risk marker for the development of cognitive impairment.

[Social cognition and cognitive functions in patients with epilepsy treated with eslicarbazepine acetate]

INTRODUCTION

Epilepsy is accompanied by cognitive disorders, frequently aggravated by the use of antiepileptic drugs, which can affect social empathy.

AIM

To analyse the impact of treatment with eslicarbazepine acetate (ESL) on social cognition and prefrontal cognitive functions in adults with focal epilepsy.

PATIENTS AND METHODS

We conducted a prospective single-centre study with patients aged between 18 and 65 years with focal seizures treated with ESL. The patients were evaluated in their baseline visit and at six months after starting ESL treatment by means of tasks designed for theory of mind, executive and attentional functions, auditory-verbal memory, quality of life, and anxiety and depression.

RESULTS

Forty-one patients were treated with ESL, and 30 completed the follow-up. A significant improvement was observed in the theory of mind tasks. In the analysis stratified by sex, the men showed greater improvement. A cognitive improvement was observed in the Wisconsin Card Sorting Test, Symbol Digit, Backward Digit Span and Stroop tests. No differences were found in the Quality of Life in Epilepsy-31 Inventory or in the Hospital Anxiety and Depression Scale. These results were independent of the reduction in the number of seizures and the ESL dosage.

CONCLUSION

Treatment with ESL could improve some aspects of theory of mind in patients with epilepsy, especially in men and independently of the control of seizures, with no changes in quality of life, anxiety or depression.

The impact of family history on non-medullary thyroid cancer

INTRODUCTION

Around 10% of patients with non-medullary thyroid cancer (NMTC) will have a positive family history for the disease. Although many will be sporadic, families where 3 first-degree relatives are affected can be considered to represent true familial non-medullary thyroid cancer (FNMTC). The genetic basis, impact on clinical and pathological features, and overall effect on prognosis are poorly understood.

METHODS

A literature review identified articles which report on genetic, clinical, therapeutic and screening aspects of FNMTC. The results are presented to allow an understanding of the genetic basis and the impact on clinical-pathological features and prognosis in order to inform clinical decision making.

RESULTS

The genetic basis of FNMTC is unknown. Despite this, significant progress has been made in identifying potential susceptibility genes. The lack of a test for FNMTC has led to a clinical definition requiring a minimum of 3 first-degree relatives to be diagnosed with NMTC. Although some have shown an association with multi-centric disease, younger age and increased rates of extra-thyroidal extension and nodal metastases, these findings are not supported by all. The impact of FNMTC is unclear with all groups reporting good outcome, and some finding an association with more aggressive disease. The role of screening remains controversial.

CONCLUSION

FNMTC is rare but can be diagnosed clinically. Its impact on prognostic factors and the subsequent role in influencing management is debated. For those patients who present with otherwise low-risk differentiated thyroid cancer, FNMTC should be included in risk assessment when discussing therapeutic options.

BEHAVIOUR OF EARLY THYROGLOBULIN AFTER TOTAL THYROIDECTOMY FOR DIFFERENTIATED THYROID CANCER

Context

The objectives of treatment of thyroid carcinoma include hormonal suppression, radioiodine ablation and follow-up with serum thyroglobulin (Tg). Tg levels should not be measured before six weeks post-thyroidectomy.

Objective

To describe the behaviour of early postoperative Tg in patients who underwent total thyroidectomy and its ability to predict the serum Tg levels after suppression.

Design

This is a retrospective cohort study.

Subjects and methods

Adult patients who underwent total thyroidectomy with at least two postoperative measurements of serum Tg, negative TgAb and concomitant serum TSH values were included. Tg, TgAb and TSH level measurements were completed two weeks postoperatively and during the follow-up period.

Results

Twenty-nine patients fulfilled all criteria. The median serum Tg level at two weeks after surgery was 3.8 ug/L (0.3 -300) with a serum TSH level of 69.9 mU/L; 11-227. At the two-week measurement, 16 (55%) patients had serum Tg levels lower than 5 ug/L and 4 patients had levels between 5-10 µg/L.

Conclusions

Postoperative early serum Tg could be an alternative to values measured six months after surgery and could be used as a predictive tool to make earlier therapeutic decisions.

Genetic Diversity and Aggressiveness of Ralstonia solanacearum Strains Causing Bacterial Wilt of Potato in Uruguay

Bacterial wilt, caused by Ralstonia solanacearum, is a major disease affecting potato (Solanum tuberosum) production worldwide. Although local reports suggest that the disease is widespread in Uruguay, characterization of prevalent R. solanacearum strains in that country has not been done. In all, 28 strains of R. solanacearum isolated from major potato-growing areas in Uruguay were evaluated, including 26 strains isolated from potato tubers and 2 from soil samples. All strains belonged to phylotype IIB, sequevar 1 (race 3, biovar 2). Genetic diversity of strains was assessed by repetitive-sequence polymerase chain reaction, which showed that the Uruguayan strains constituted a homogeneous group. In contrast, inoculation of the strains on tomato and potato plants showed, for the first time, different levels of aggressiveness among R. solanacearum strains belonging to phylotype IIB, sequevar 1. Aggressiveness assays were also performed on accessions of S. commersonii, a wild species native to Uruguay that is a source of resistance for potato breeding. No significant interactions were found between bacterial strains and potato and S. commersonii genotypes, and differences in aggressiveness among R. solanacearum strains were consistent with previously identified groups based on tomato and potato inoculations. Moreover, variation in responses to R. solanacearum was observed among the S. commersonii accessions tested.

Elective neck dissection in oral carcinoma: a critical review of the evidence

More than 50% of patients with squamous cell carcinoma of the oral cavity have lymph node metastases and histological confirmation of metastatic disease is the most important prognostic factor. Among patients with a clinically negative neck, the incidence of occult metastases varies with the site, size and thickness of the primary tumour. The high incidence rate of occult cervical metastases (> 20%) in tumours of the lower part of the oral cavity is the main argument in favour of elective treatment of the neck. The usual treatment of patients with clinically palpable metastatic lymph nodes has been radical neck dissection. This classical surgical procedure involves not only resection of level I to V lymph nodes of the neck but also the tail of the parotid, submandibular gland, sternocleidomastoid muscle, internal jugular vein and spinal accessory nerve. It is a safe oncological surgical procedure that significantly reduces the risk of regional recurrences, however it produces significant post-operative morbidity, mainly shoulder dysfunction. Aiming to reduce morbidity, Ward and Roben described a modification of the procedure sparing the spinal accessory nerve to prevent post-operative shoulder morbidity. Several clinical and pathological studies have demonstrated that the pattern of metastatic lymph node metastases occurs in a predictable fashion in patients with oral and oropharyngeal carcinoma. The use of selective supraomohyoid neck dissection as the elective treatment of the neck, in oral cancer patients, is now well established. However, its role in the treatment of clinically positive neck patients is controversial. Some Authors advocate this type of selective neck dissection in patients with limited neck disease at the upper levels of the neck, without jeopardizing neck control. The main factors supporting this approach are the usually good prognosis in patients with single levels I or II metastasis independent of the extent of neck dissection, and the low rates of level V involvement in oral cavity tumours. Furthermore, the high incidence of clinically false-positive lymph nodes in oral cavity cancer patients is well recognized. In selected cases, supraomohyoid dissection could be extended to level IV, and followed by radiotherapy when indicated. Several reports have confirmed the usefulness of minimally invasive sentinel lymph node biopsy in melanoma and breast tumours. However, only preliminary data testing the feasibility of the method exist regarding the management of oral and oropharyngeal squamous cell carcinoma. The complexity of lymphatic drainage and the presence of deep lymphatics of the neck make application of this method difficult. This attractive concept has recently been explored by several investigators who examined the feasibility of identifying the sentinel lymph node in primary echelons of drainage from oral cavity squamous carcinoma. The current knowledge of sentinel lymph node biopsy does not allow avoiding the indication of elective neck dissection in clinical practice. Sentinel lymph node biopsy cannot be considered the standard of care at this time. However, there are multi-institutional clinical trials testing this approach. Management of occult neck node metastasis continues to be a matter of debate. The role of imaging methods such as ultrasound-guided needle biopsy, sentinel node biopsy and positron emission tomography-computed tomography are still being evaluated as alternatives to elective neck dissections. Whether one of these techniques will change the current management of cervical node metastasis remains to be proved in prospective multi-institutional trials.

Penetrating stab wounds to the abdomen: use of serial US and contrast-enhanced CT in stable patients

PURPOSE

To evaluate the usefulness of computed tomography (CT) and ultrasonography (US) for the initial assessment of penetrating abdominal stab wounds in patients who presented to the emergency department without indication for immediate laparotomy.

MATERIALS AND METHODS

During 36 months, 32 patients with a penetrating stab wound to the abdomen were examined with serial US (at admission and 12 hours later) and helical CT, with contrast material administered orally, intravenously, and rectally. Presence of hemoperitoneum and integrity of solid and hollow viscera were evaluated with both methods. Sonograms were interpreted by the radiologist who performed the examination, and CT images were independently evaluated by two radiologists. Findings of both techniques were compared with clinical outcome and/or surgical findings.

RESULTS

One (3.1%) of 32 patients required surgery: Surgical findings were massive hemoperitoneum and an extensive hepatic laceration. Both US and CT depicted these abnormalities. Thirty-one (96.9%) patients were treated conservatively, without surgery, and remained asymptomatic during 28 days of clinical follow-up after discharge from the hospital. US and/or CT showed intraperitoneal abnormalities in 21 of these patients. In 11 patients, both methods showed no evidence of visceral injury or hemoperitoneum, and none of these patients required surgery.

CONCLUSION

Serial US and CT help guide treatment for stable patients with penetrating stab injuries to the abdomen.

Focal arterial injuries of the proximal extremities: helical CT arteriography as the initial method of diagnosis

PURPOSE

To present our experience with helical computed tomographic (CT) arteriography as the initial diagnostic examination in patients suspected to have focal arterial injuries of the proximal extremities.

MATERIALS AND METHODS

During 19 months, 142 arterial segments in the proximal portions of the extremities of 139 patients with trauma were evaluated with helical CT arteriography. CT arteriograms were interpreted on site by the radiologist in charge of emergency procedures and retrospectively with consensus interpretation between two radiologists. CT study quality and the presence of arterial injuries were noted. CT arteriographic findings were compared with those of surgery, conventional arteriography, and/or clinical follow-up.

RESULTS

Five (3.6%) patients had nondiagnostic studies and underwent conventional arteriography. In the remaining 137 arterial segments in 134 patients, helical CT arteriography demonstrated arterial injuries in 61 segments and normal arteries in 76 segments. These segments were treated initially with surgery (55 segments) or endovascular intervention (four segments) or were observed (78 segments); 77 of the 78 observed segments remained stable at 3-18 months (mean follow-up, 5.2 months). There were no differences between the on-site and consensus interpretations (kappa = 1.0). The sensitivity of CT arteriography was 95.1%, and the specificity was 98.7%.

CONCLUSION

Helical CT arteriography can be performed as the initial diagnostic method in most patients suspected to have focal arterial injuries of the proximal portions of the extremities.

[Relationship between HLA antigens and the HIV infection in patients from the state of Zulia]

PURPOSE

Some genetic factors associated to the HLA system phenotypes may allegedly predispose to the development of infection in patients exposed to the human immunodeficiency virus (HIV). So the aim of this study was to assess if certain HLA antigens are positive or negative risk factors in the development of AIDS in Zulia State.

PATIENTS AND METHODS

A total of 62 samples were studied, 31 from HIV seropositive subjects and 31 form healthy individuals. The patients were subclassified into four groups in accordance with Atlanta's CDC guidelines. Tests for histocompatibility including HLA-A-B-C, DR and DQ typing were performed with Terasaki's technique. VIH positivity was determined by ELISA and confirmed by Western Blot. The statistical evalub1p4n was performed with the chi 2 test for antigen frequency comparison, the relative risk (RR) was estimated with the Ryder and Svelgaard test, and the inferential analysis was made by means of non-parametric statistics.

RESULTS

Most patients were included in CDC's groups II and IV, 48.4% and 29.0%, respectively. Increased B35 and DQw2 and decreased B39 and DR2 antigens were found when comparing the HLA distribution in the sample and the antigenic frequency of the population. RR > 1 was observed in the infected patients A for A1, A3, A10, A11, B5, B7, B12, B14, B35, B61, CW4, DR4, DRW52 and DQW2 HLA antigens. A positive association between symptomatic infected patients and antigen B35 was present (X = 7.045).

CONCLUSION

The findings reported here suggest that antigen B35 is a major risk factor for the development of AIDS.

Acute hypotensive action of clonidine after intravenous infusion in hypertensive emergencies

Clonidine was administered by intravenous infusion to 12 patients classified as having exaggerated arterial hypertension, their systolic (SAP), diastolic (DAP) and mean (MAP) arterial pressures were significantly reduced from the third min. The maximal percentage reduction (Mean +/- SEM) reached 30.1 +/- 3.1% (SAP) and 24.7 +/- 2.9% (DAP) after 30 to 110 min of infusion. Initially there were transitory initial increases in SAP (3 patients) and DAP (1 patient). The increases in blood pressure were related to low body surface area (BSA). The dose of clonidine per m2BSA able to reduce by 10% either SAP or DAP (active dose-10), and the dose able to reduce SAP or DAP by 10 mmHg in one minute (systolic or diastolic clonidine unit) were calculated, providing indices for detecting clonidine responsiveness in patients with exaggerated hypertension. This method is advantageous when using clonidine intravenously because it diminishes the risk of overdosage.