First report of frequencies of Y chromosome microdeletions at a reproductive medicine center in Peru

Objective

Y chromosome Microdeletions are the second genetic cause of infertility in men. Despite its importance for infertility treatment, there is no previous research in Peru. The aim of this study was to determine the frequencies and characteristics of Y chromosome microdeletions in a group of men who sought infertility consultation at a specialized reproductive medicine center in Peru.

Methods

In this study, 201 semen samples were analyzed. The samples were obtained from Niu Vida's fertility program. Each seminal sample was analyzed according to the recommendations of the Laboratory Manual of the World Health Organization (WHO) 2010. A buccal swab and a 500 μL aliquot of seminal sample were used for the molecular study of Y chromosome microdeletions in each patient. The frequencies and the type of Y chromosome microdeletion in the AZFa, AZFb and AZFc regions were evaluated.

Results

The prevalence of Y chromosome microdeletions in the AZF region was 6.45% in oligozoospermic and azoospermic patients, and a prevalence of 20% was observed specifically in azoospermic patients. No microdeletions of AZFb type were detected. A partial region microdeletion of AZFa was detected in a teratozoospermic patient with a normal sperm count.

Conclusions

The study represents the first report on the incidence of Y chromosome microdeletions in Peru. Our results indicate a high prevalence of microdeletions in azoospermic patients compared to similar studies. It is suggested to assess the presence of AZFa microdeletions and to evaluate additional genetic markers in this region to identify specific mutations that may cause impaired sperm production and male infertility in the Peruvian male population.

γ-Linolenic acid in maternal milk drives cardiac metabolic maturation

Birth presents a metabolic challenge to cardiomyocytes as they reshape fuel preference from glucose to fatty acids for postnatal energy production1,2. This adaptation is triggered in part by post-partum environmental changes3, but the molecules orchestrating cardiomyocyte maturation remain unknown. Here we show that this transition is coordinated by maternally supplied γ-linolenic acid (GLA), an 18:3 omega-6 fatty acid enriched in the maternal milk. GLA binds and activates retinoid X receptors4 (RXRs), ligand-regulated transcription factors that are expressed in cardiomyocytes from embryonic stages. Multifaceted genome-wide analysis revealed that the lack of RXR in embryonic cardiomyocytes caused an aberrant chromatin landscape that prevented the induction of an RXR-dependent gene expression signature controlling mitochondrial fatty acid homeostasis. The ensuing defective metabolic transition featured blunted mitochondrial lipid-derived energy production and enhanced glucose consumption, leading to perinatal cardiac dysfunction and death. Finally, GLA supplementation induced RXR-dependent expression of the mitochondrial fatty acid homeostasis signature in cardiomyocytes, both in vitro and in vivo. Thus, our study identifies the GLA-RXR axis as a key transcriptional regulatory mechanism underlying the maternal control of perinatal cardiac metabolism.

Retinoid X receptor promotes hematopoietic stem cell fitness and quiescence and preserves hematopoietic homeostasis

Hematopoietic stem cells (HSCs) balance self-renewal and differentiation to maintain hematopoietic fitness throughout life. In steady-state conditions, HSC exhaustion is prevented by the maintenance of most HSCs in a quiescent state, with cells entering the cell cycle only occasionally. HSC quiescence is regulated by retinoid and fatty-acid ligands of transcriptional factors of the nuclear retinoid X receptor (RXR) family. Herein, we show that dual deficiency for hematopoietic RXRα and RXRβ induces HSC exhaustion, myeloid cell/megakaryocyte differentiation, and myeloproliferative-like disease. RXRα and RXRβ maintain HSC quiescence, survival, and chromatin compaction; moreover, transcriptome changes in RXRα;RXRβ-deficient HSCs include premature acquisition of an aging-like HSC signature, MYC pathway upregulation, and RNA intron retention. Fitness loss and associated RNA transcriptome and splicing alterations in RXRα;RXRβ-deficient HSCs are prevented by Myc haploinsufficiency. Our study reveals the critical importance of RXRs for the maintenance of HSC fitness and their protection from premature aging.

Macrophages promote endothelial-to-mesenchymal transition via MT1-MMP/TGFβ1 after myocardial infarction

Macrophages (Mφs) produce factors that participate in cardiac repair and remodeling after myocardial infarction (MI); however, how these factors crosstalk with other cell types mediating repair is not fully understood. Here we demonstrated that cardiac Mφs increased the expression of Mmp14 (MT1-MMP) 7 days post-MI. We selectively inactivated the Mmp14 gene in Mφs using a genetic strategy (Mmp14^f/f:Lyz2-Cre). This conditional KO (MAC-Mmp14 KO) resulted in attenuated post-MI cardiac dysfunction, reduced fibrosis, and preserved cardiac capillary network. Mechanistically, we showed that MT1-MMP activates latent TGFβ1 in Mφs, leading to paracrine SMAD2-mediated signaling in endothelial cells (ECs) and endothelial-to-mesenchymal transition (EndMT). Post-MI MAC-Mmp14 KO hearts contained fewer cells undergoing EndMT than their wild-type counterparts, and Mmp14-deficient Mφs showed a reduced ability to induce EndMT in co-cultures with ECs. Our results indicate the contribution of EndMT to cardiac fibrosis and adverse remodeling post-MI and identify Mφ MT1-MMP as a key regulator of this process.

Relapsing-Remitting Multiple Sclerosis Is Characterized by a T Follicular Cell Pro-Inflammatory Shift, Reverted by Dimethyl Fumarate Treatment

Multiple sclerosis (MS) is considered a T cell-mediated autoimmune disease, although several evidences also demonstrate a B cell involvement in its etiology. Follicular T helper (Tfh) cells, a CXCR5-expressing CD4+ T cell subpopulation, are essential in the regulation of B cell differentiation and maintenance of humoral immunity. Alterations in circulating (c)Tfh distribution and/or function have been associated with autoimmune diseases including MS. Dimethyl fumarate (DMF) is a recently approved first-line treatment for relapsing-remitting MS (RRMS) patients whose mechanism of action is not completely understood. The aim of our study was to compare cTfh subpopulations between RRMS patients and healthy subjects and evaluate the impact of DMF treatment on these subpopulations, relating them to changes in B cells and humoral response. We analyzed, by flow cytometry, the distribution of cTfh1 (CXCR3+CCR6-), cTfh2 (CXCR3-CCR6-), cTfh17 (CXCR3-CCR6+), and the recently described cTfh17.1 (CXCR3+CCR6+) subpopulations of CD4+ Tfh (CD45RA-CXCR5+) cells in a cohort of 29 untreated RRMS compared to healthy subjects. CD4+ non-follicular T helper (Th) cells (CD45RA-CXCR5-) were also studied. We also evaluated the effect of DMF treatment on these subpopulations after 6 and 12 months treatment. Untreated RRMS patients presented higher percentages of cTfh17.1 cells and lower percentages of cTfh2 cells consistent with a pro-inflammatory bias compared to healthy subjects. DMF treatment induced a progressive increase in cTfh2 cells, accompanied by a decrease in cTfh1 and the pathogenic cTfh17.1 cells. A similar decrease of non-follicular Th1 and Th17.1 cells in addition to an increase in the anti-inflammatory Th2 subpopulation were also detected upon DMF treatment, accompanied by an increase in naïve B cells and a decrease in switched memory B cells and serum levels of IgA, IgG2, and IgG3. Interestingly, this effect was not observed in three patients in whom DMF had to be discontinued due to an absence of clinical response. Our results demonstrate a possibly pathogenic cTfh pro-inflammatory profile in RRMS patients, defined by high cTfh17.1 and low cTfh2 subpopulations that is reverted by DMF treatment. Monitoring cTfh subsets during treatment may become a biological marker of DMF effectiveness.

[Pulmonary lobectomy in children: the sooner the better?]

AIM OF THE STUDY

Recommendation of early pulmonary resection in asymptomatic congenital pulmonary airway malformations (CPAMs) is based on the presumed compensatory lung growth during the first months of life. Our aim is to analyze the long-term pulmonary function after lobectomy before and after one year of age using spirometry.

METHODS

We performed a retrospective review of children who underwent pulmonary lobectomy for CPAM between 2001 and 2016. Patients who were old enough (>5 years) to carry out a spirometry were included in the study and were divided into 2 groups (surgery before or after 12 months of age). Pulmonary function testing values were considered normal if they were >80% of predicted.

MAIN RESULTS

Forty-seven patients underwent pulmonary lobectomy for CPAM, 23 of them met the inclusion criteria and prospectively performed a spirometry. Among them, 7 had surgery before and 16 after one year of age (0.1 vs. 2); being both groups comparable in terms of sex, type of CPAM and surgical approach. Time from surgery until pulmonary function testing was longer in patients who had surgery before one year of age (9.1 vs. 4.6 years, p = 0.003). After correcting results by time from surgery until spirometry, a better FEV1/FVC was found in patients who had surgery after one year of age (90% vs. 77%, p = 0.043).

CONCLUSION

Although spirometry may be influenced by many other variables, these preliminary results do not support the current recommendation of performing early lobectomy in CPAMs. Further studies are required in order to resolve the best age to perform pulmonary lobectomy.

[The role of fetal magnetic resonance imaging in the study of congenital diaphragmatic hernia]

INTRODUCTION AND OBJECTIVES

Different echographic and fetal magnetic resonance (MRI) measurements have been described in the diagnosis of associated malformations and the prognosis of congenital diaphragmatic hernia (CDH). We have reviewed our experience searching for useful isolated or combined parameters and how MRI can complement ultrasound.

MATERIAL AND METHODS

We evaluated 29 fetuses with CDH. We examined ultrasonography: Lung to Head (LHR o/e) and in MRI: ipsilateral lung volume (IPV) and total expressed as percentage of observed / expected lung volume (VPT o/e) and percentage of herniated liver (PHH). We studied: survival, ECMO and associated malformations.

RESULTS

LHR o/e was the measure that best predicted survival (p< 0.05). VPT o/e did not predict survival or the need of ECMO (p> 0.05). PHH ≥19% was related to the need of ECMO. IPV < 2 cc required ECMO more frequently (p< 0.018) and when it was 0 cc in all cases. No combination of MR measurements was superior to LHR o/e in prediction of survival. MRI complemented the ultrasound in 4 cases: diaphragmatic eventration diagnosed with HDC, right HDC with fluid in the sac that suggested thoracic cyst, differentiation between spleen and lung that measured together overestimated the LHR and/or suspicion of Cornelia de Lange due to facial malformations.

CONCLUSIONS

Not a single or combined MRI measurement exceeds LHR o/e in survival prediction. MRI is related to prognosis and can be used to support ultrasound in making decisions. MRI occasionally provides complementary morphological information.

[Nissen fundoplication in children under 1 year of age: is age important?]

AIM

Nissen fundoplication (NF) is a procedure with technical difficulties and variable functional prognosis the lower the patient's age is. Our objective is to analyze the peculiarities of this procedure when performed in children under 1 year.

MATERIALS AND METHODS

Retrospective study of the NF in our center from 1999 to 2014. We review the differences between children under 1 year of age and the leftover of the series: history, indications, surgical approach and postoperative outcomes.

RESULTS

A total of 233 patients (57.1% male) were operated at a median age of 2.3years (1 month-17.31years), of which 82 (35.2%) were younger than 1 year. It Open surgery was performed in 118 patients (86.6% of children under 1 year and 31.1% over 1 year, p <0.05) and laparoscopic in 115. The median follow-up was 3.92 ± 3.24 years. Patients under 1 year had a higher number of comorbidities (91.5% vs 81.5%), respiratory symptoms (76.8% vs 49.7%) and postoperative complications (20.7% vs 9.9% OR = 2.4), with statistically significant differences (p <0.05). There were not differences in the Nissen's failure rate (15.9% vs 8.6%) or the need of reoperation (15.9% vs 7.9%).

CONCLUSIONS

Patients under 1 year operated by NF form a group with particular indications and comorbidities. Although the outcomes among these patients are favourable, surgical complications are more frequent than in older children.

Retinoid X receptors orchestrate osteoclast differentiation and postnatal bone remodeling

Osteoclasts are bone-resorbing cells that are important for maintenance of bone remodeling and mineral homeostasis. Regulation of osteoclast differentiation and activity is important for the pathogenesis and treatment of diseases associated with bone loss. Here, we demonstrate that retinoid X receptors (RXRs) are key elements of the transcriptional program of differentiating osteoclasts. Loss of RXR function in hematopoietic cells resulted in formation of giant, nonresorbing osteoclasts and increased bone mass in male mice and protected female mice from bone loss following ovariectomy, which induces osteoporosis in WT females. The increase in bone mass associated with RXR deficiency was due to lack of expression of the RXR-dependent transcription factor v-maf musculoaponeurotic fibrosarcoma oncogene family, protein B (MAFB) in osteoclast progenitors. Evaluation of osteoclast progenitor cells revealed that RXR homodimers directly target and bind to the Mafb promoter, and this interaction is required for proper osteoclast proliferation, differentiation, and activity. Pharmacological activation of RXRs inhibited osteoclast differentiation due to the formation of RXR/liver X receptor (LXR) heterodimers, which induced expression of sterol regulatory element binding protein-1c (SREBP-1c), resulting in indirect MAFB upregulation. Our study reveals that RXR signaling mediates bone homeostasis and suggests that RXRs have potential as targets for the treatment of bone pathologies such as osteoporosis.

Differential lipid partitioning between adipocytes and tissue macrophages modulates macrophage lipotoxicity and M2/M1 polarization in obese mice

OBJECTIVE

Obesity-associated insulin resistance is characterized by a state of chronic, low-grade inflammation that is associated with the accumulation of M1 proinflammatory macrophages in adipose tissue. Although different evidence explains the mechanisms linking the expansion of adipose tissue and adipose tissue macrophage (ATM) polarization, in the current study we investigated the concept of lipid-induced toxicity as the pathogenic link that could explain the trigger of this response.

RESEARCH DESIGN AND METHODS

We addressed this question using isolated ATMs and adipocytes from genetic and diet-induced murine models of obesity. Through transcriptomic and lipidomic analysis, we created a model integrating transcript and lipid species networks simultaneously occurring in adipocytes and ATMs and their reversibility by thiazolidinedione treatment.

RESULTS

We show that polarization of ATMs is associated with lipid accumulation and the consequent formation of foam cell-like cells in adipose tissue. Our study reveals that early stages of adipose tissue expansion are characterized by M2-polarized ATMs and that progressive lipid accumulation within ATMs heralds the M1 polarization, a macrophage phenotype associated with severe obesity and insulin resistance. Furthermore, rosiglitazone treatment, which promotes redistribution of lipids toward adipocytes and extends the M2 ATM polarization state, prevents the lipid alterations associated with M1 ATM polarization.

CONCLUSIONS

Our data indicate that the M1 ATM polarization in obesity might be a macrophage-specific manifestation of a more general lipotoxic pathogenic mechanism. This indicates that strategies to optimize fat deposition and repartitioning toward adipocytes might improve insulin sensitivity by preventing ATM lipotoxicity and M1 polarization.

Autoimmune kidney disease and impaired engulfment of apoptotic cells in mice with macrophage peroxisome proliferator-activated receptor gamma or retinoid X receptor alpha deficiency

Autoimmune glomerulonephritis is a common manifestation of systemic lupus erythematosus (SLE). In this study, we show that mice lacking macrophage expression of the heterodimeric nuclear receptors PPARγ or RXRα develop glomerulonephritis and autoantibodies to nuclear Ags, resembling the nephritis seen in SLE. These mice show deficiencies in phagocytosis and clearance of apoptotic cells, and they are unable to acquire an anti-inflammatory phenotype upon feeding of apoptotic cells, which is critical for the maintenance of self-tolerance. These results demonstrate that stimulation of PPARγ and RXRα in macrophages facilitates apoptotic cell engulfment, and they provide a potential strategy to avoid autoimmunity against dying cells and to attenuate SLE.

Retinoid X receptor alpha controls innate inflammatory responses through the up-regulation of chemokine expression

The retinoid X receptor alpha (RXRalpha) plays a central role in the regulation of many intracellular receptor signaling pathways and can mediate ligand-dependent transcription by forming homodimers or heterodimers with other nuclear receptors. Although several members of the nuclear hormone receptor superfamily have emerged as important regulators of macrophage gene expression, the existence in vivo of an RXR signaling pathway in macrophages has not been established. Here, we provide evidence that RXRalpha regulates the transcription of the chemokines Ccl6 and Ccl9 in macrophages independently of heterodimeric partners. Mice lacking RXRalpha in myeloid cells exhibit reduced levels of CCL6 and CCL9, impaired recruitment of leukocytes to sites of inflammation, and lower susceptibility to sepsis. These studies demonstrate that macrophage RXRalpha plays key roles in the regulation of innate immunity and represents a potential target for immunotherapy of sepsis.

Scorpion envenoming in two regions of Colombia: clinical, epidemiological and therapeutic aspects

To determine clinical and epidemiological features of scorpion stings in two departments of Colombia, a descriptive study was performed in the hospitals of 10 towns from Antioquia (2 256 071 inhabitants) and five from Tolima (630 424 inhabitants). One hundred and twenty-nine cases were admitted during one year, 51 in Antioquia, 78 in Tolima and 41 were children less than 15 years old. Most stings (70.5%) occurred inside the house; 27.9% were on the hands and 26.4% on the feet. The scorpion species involved were Tityus pachyurus (51), Centruroides gracilis (31), T. fuehrmanni (29), T. asthenes (7) and Chactas spp. (1). In 10 cases the scorpion involved was not identified. Systemic envenoming signs (e.g. vomiting, tachypnea) were significantly more frequent in children than in adults (P < 0.05). Four children had hypertension, but none developed pulmonary oedema. One 3-year-old girl, stung by T. asthenes, had acute oedematous pancreatitis. Ninety-eight patients had mild envenoming. Moderate (27 patients) and severe (four patients) envenoming was significantly more frequent in children than in adults (P = 0.003; relative risk = 2.97). A pepsin-digested anti-Centruroides spp. antivenom was administered to 19 of 31 patients presenting systemic envenoming signs. No adverse reactions to antivenom were observed.

Neutralization of the edema-forming, defibrinating and coagulant effects of Bothrops asper venom by extracts of plants used by healers in Colombia

We determined the neutralizing activity of 12 ethanolic extracts of plants against the edema-forming, defibrinating and coagulant effects of Bothrops asper venom in Swiss Webster mice. The material used consisted of the leaves and branches of Bixa orellana (Bixaceae), Ficus nymphaeifolia (Moraceae), Struthanthus orbicularis (Loranthaceae) and Gonzalagunia panamensis (Rubiaceae); the stem barks of Brownea rosademonte (Caesalpiniaceae) and Tabebuia rosea (Bignoniaceae); the whole plant of Pleopeltis percussa (Polypodiaceae) and Trichomanes elegans (Hymenophyllaceae); rhizomes of Renealmia alpinia (Zingiberaceae), Heliconia curtispatha (Heliconiaceae) and Dracontium croatii (Araceae), and the ripe fruit of Citrus limon (Rutaceae). After preincubation of varying amounts of each extract with either 1.0 microg venom for the edema-forming effect or 2.0 microg venom for the defibrinating effect, the mixture was injected subcutaneously (sc) into the right foot pad or intravenously into the tail, respectively, to groups of four mice (18-20 g). All extracts (6.2-200 microg/mouse) partially neutralized the edema-forming activity of venom in a dose-dependent manner (58-76% inhibition), with B. orellana, S. orbicularis, G. panamensis, B. rosademonte, and D. croatii showing the highest effect. Ten extracts (3.9-2000 microg/mouse) also showed 100% neutralizing ability against the defibrinating effect of venom, and nine prolonged the coagulation time induced by the venom. When the extracts were administered either before or after venom injection, the neutralization of the edema-forming effect was lower than 40% for all extracts, and none of them neutralized the defibrinating effect of venom. When they were administered in situ (sc at the same site 5 min after venom injection), the neutralization of edema increased for six extracts, reaching levels up to 64% for C. limon.

[Subclinical carotid atherosclerosis in patients with coronary disease]

BACKGROUND

B-mode ultrasonography is a simple and valid method to evaluate subclinical atherosclerosis of the major superficial arteries. The aim of this study was toknow by this technique the prevalence of carotid atherosclerosisin patients with coronary disease and related factors.

PATIENTS AND METHOD

In 232patients (205 men and 27 women; age: mean [standard deviation]59 [8] years) with coronary disease, intima-media thickness (IMT),presence and number of atheroma plaques in carotid arteries wereevaluated by B-mode ultrasonography. Controls were 50 healthy subjects whose age was not different from patients. Carotid atherosclerosis was considered when IMT was higher than mean plus two standarddeviations of control values, and/or existence of atheroma plaques.

RESULTS

Carotid IMT wasincreased in patients compared to controls 0.82 [0.22] vs 0.62[0.12] mm; p < 0.001) and there were more patients with plaques(67 vs 20%; p < 0.001). Carotid atherosclerosis was found in170 patients and 11 controls (73 vs 22%; p < 0.001). By multivariate analysis, carotid atherosclerosis was associated with age (oddsratio: 1.05; 95% confidence interval [CI], 1.01-1.09) and smoking(odds ratio, 2.11; 95% CI: 1.04-4.26). The presence of more thanone plaque was associated with levels of low-density-lipoprotein(LDL)-cholesterol (odds ratio, 1.01; 95% CI, 1.00-1.02).

CONCLUSIONS

In the patients with coronary disease, prevalence of subclinical carotid atherosclerosisis very high (73%), and it is associated with age and smoking. The advanced stage of atherosclerosis, evaluated by the existence of more than one plaque, is correlated with LDL-cholesterol levels.

Snakebites and ethnobotany in the northwest region of Colombia. Part III: neutralization of the haemorrhagic effect of Bothrops atrox venom

Thirty-one of 75 extracts of plants used by traditional healers for snakebites, had moderate or high neutralizing ability against the haemorrhagic effect of Bothrops atrox venom from Antioquia and Chocó, north-western Colombia. After preincubation of several doses of every extract (7.8-4000 microg/mouse) with six minimum haemorrhagic doses (10 microg) of venom, 12 of them demonstrated 100% neutralizing capacity when the mixture was i.d. injected into mice (18-20 g). These were the stem barks of Brownea rosademonte (Caesalpiniaceae) and Tabebuia rosea (Bignoniaceae); the whole plants of Pleopeltis percussa (Polypodiaceae), Trichomanes elegans (Hymenophyllaceae) and Senna dariensis (Caesalpiniaceae); rhizomes of Heliconia curtispatha (Heliconiaceae); leaves and branches of Bixa orellana (Bixaceae), Philodendron tripartitum (Araceae), Struthanthus orbicularis (Loranthaceae) and Gonzalagunia panamensis (Rubiaceae); the ripe fruits of Citrus limon (Rutaceae); leaves, branches and stem of Ficus nymphaeifolia (Moraceae). Extracts of another 19 species showed moderate neutralization (21-72%) at doses up to 4 mg/mouse, e.g. the whole plants of Aristolochia grandiflora (Aristolochiaceae), Columnea kalbreyeriana (Gesneriaceae), Sida acuta (Malvaceae), Selaginella articulata (Selaginellaceae) and Pseudoelephantopus spicatus (Asteraceae); rhizomes of Renealmia alpinia (Zingiberaceae); the stem of Strychnos xinguensis (Loganiaceae); leaves, branches and stems of Hyptis capitata (Lamiaceae), Ipomoea cairica (Convolvulaceae), Neurolaena lobata (Asteraceae), Ocimum micranthum (Lamiaceae), Piper pulchrum (Piperaceae), Siparuna thecaphora (Monimiaceae), Castilla elastica (Moraceae) and Allamanda cathartica (Apocynaceae); the macerated ripe fruits of Capsicum frutescens (Solanaceae); the unripe fruits of Crescentia cujete (Bignoniaceae); leaves and branches of Piper arboreum (Piperaceae) and Passiflora quadrangularis (Passifloraceae). When the extracts were independently administered by oral, i.p. or i.v. route either before or after an i.d. venom injection (10 microg), neutralization of haemorrhage dropped below 25% for all the extracts. Additionally, B. rosademonte and P. percussa extracts were able to inhibit the proteolytic activity of B. atrox venom on casein.

Snakebites and ethnobotany in the northwest region of Colombia: Part II: neutralization of lethal and enzymatic effects of Bothrops atrox venom

Twelve of 74 ethanolic extracts of plants used by traditional healers for snakebites in the northwest region of Colombia, were active against lethal effect of Bothrops atrox venom when they were i.p. injected into mice (18-20 g). After preincubation of sublethal doses of every extract (0.5-4.0 mg/mouse) with 1.5 i.p. lethal dose 50% (LD50) (99.3 microg) of venom, seven of them demonstrated 100% neutralizing capacity within 48 h. These were the stem barks of Brownea rosademonte (Caesalpiniaceae) and Tabebuia rosea (Bignoniaceae); rhizomes of Renealmia alpinia (Zingiberaceae) and Heliconia curtispatha (Heliconiaceae); the whole plants of Pleopeltis percussa (Polypodiaceae) and Trichomanes elegans (Hymenophyllaceae); and the ripe fruits of Citrus limon (Rutaceae). The other five extracts showing partial neutralization (45-80%; 10-30% survival rate in the control group receiving the venom alone; P<0.05) were: leaves, branches and stem of Costus lasius (Costaceae); the whole plant of Sida acuta (Malvaceae); rhizomes of Dracontium croatii (Araceae); leaves and branches of Bixa orellana (Bixaceae) and Struthanthus orbicularis (Loranthaceae). When the extracts were independently administered per oral or i.p. route 60 min before an i.m. venom injection (204 microg=1.5 i.m. LD50), C. limon, T. elegans, B. orellana and T. rosea extracts had partial and significant neutralizing capacity against B. atrox venom lethal effect. C. limon extract was also partially effective when it was administered either i.v. 15 min before or i.p. 5 min after an i.m. venom injection. Three of the 12 extracts with anti-lethal effect (C. limon, D. croatii and S. acuta) were devoid of antiphospholipase A2 activity, when they were tested against one minimum indirect hemolytic dose of B. atrox venom (2 microg) in agarose-erythrocyte-egg yolk gels.

Snakebites and ethnobotany in the northwest region of Colombia: Part I: traditional use of plants

In Antioquia and Chocó, traditional healers attend 60% of snakebites. With the aim to produce an inventory of the plants used by the healers to treat snakebites and to document the methods of preparation, administration, the dosage, number of patients treated throughout their years of practice with treatment results, 20 healers with experience in Bothrops, Porthidium and Bothriechis envenomations were interviewed between August, 1996 and November, 1998. They belong to nine black and three indigenous rural communities located near the towns of Bojayá, Vigía del Fuerte, Unguía (Atrato river valley), Nuquí and Bahía Solano (Pacific coast). Based on field interviews, 101 species of plants were identified as used to treat snakebites. The part used of each plant varies according to the species. Sixty plants are used in the form of drinks prepared by infusion, decoction or maceration; 78 as external baths on the affected extremity; 11 for steam application and 39 for poultices; the latter is used mainly when the bite is complicated by local necrosis. In mild and moderate envenomations, they generally use a mixture of three plants, while in severe cases they mix from five to 12, a handful of each one. Treatment is generally performed for 1-3 days, when the patient reacts positively. They reported to have treated 454 patients during their years of experience, 20 of them (4.4%) died. With the guidance of the healers, 77 species of plants were collected and photographed. These plants belong to 41 families, of which Piperaceae (13 species), Araceae (six species), Asteraceae (five species) and Gesneriaceae (three species) have the highest number of species.

A randomized blinded clinical trial of two antivenoms, prepared by caprylic acid or ammonium sulphate fractionation of IgG, in Bothrops and Porthidium snake bites in Colombia: correlation between safety and biochemical characteristics of antivenoms

A randomized blinded clinical trial was performed in 53 patients bitten by Bothrops sp. and Porthidium sp. in Antioquia and Chocó, Colombia, in order to compare the efficacy and safety of two antivenoms made of whole IgG obtained by either ammonium sulphate (monovalent anti-B. atrox) or caprylic acid (polyvalent) fractionation. Additionally, antivenoms were compared by electrophoretic and chromatographic analyses and anticomplementary activity in vitro. With a protocol of 2, 4 and 6 antivenom vials for the treatment of mild, moderate and severe envenomings, respectively, both antivenoms were equally efficient to neutralize the most relevant signs of envenoming and to clear serum venom levels in patients from the first hour and later on. Three patients with severe envenoming and initially treated with less than six vials on admission had persistent or recurrent venom antigenemia within 12-48 h. Monovalent antivenom fractionated by ammonium sulphate precipitation had higher amounts of protein aggregates and nonimmunoglobulin proteins than polyvalent antivenom fractionated by caprylic acid precipitation. Both antivenoms presented anticomplementary activity in vitro, being higher in the monovalent product. In agreement, monovalent antivenom induced a significantly higher incidence of early antivenom reactions (52%) than polyvalent antivenom (25%).

Comparative study of the venoms of three subspecies of Lachesis muta (bushmaster) from Brazil, Colombia and Costa Rica

A comparative study was performed on the pharmacology and biochemistry of venoms from three subspecies of Lachesis muta (L. m. stenophrys, L. m. muta and L. m. rhombeata) from Brazil, Colombia and Costa Rica. All venoms induced lethal, hemorrhagic, edema-forming, myotoxic, coagulant and defibrinating effects, showing also proteolytic and indirect hemolytic activities. The venoms of L. m. stenophrys from Costa Rica and L. m. muta from Cascalheira, Brazil, had the highest lethal and hemorrhagic activities and the venom of L. m. rhombeata showed the highest coagulant activity, whereas no significant differences were observed in myotoxic and edema-forming activities at most of the time intervals studied. In addition, venoms showed similar electrophoretic patterns on SDS-polyacrylamide gel electrophoresis. In conclusion, despite quantitative differences in toxic and enzymatic activities, together with subtle variations in electrophoretic patterns, our results indicate that experimental envenomation by these venoms induce a qualitatively similar pathophysiological profile.

[Modification of the nutritional septicemic risk (RSN) by means of perioperative transfusion]

A prospective study was carried out in 207 patients with benign and neoplastic diseases of the digestive tract who were candidates for elective surgery, in order to evaluate the influence of the nutritional status and perioperative transfusions on the appearance of postoperative infections. All patients were subjected to a nutritional assessment study based on anthropometric parameters, analytical data, and cutaneous delayed hypersensitivity tests. With the aim of establishing a risk potential for postoperative infection based on the nutritional status of the patients, a multi-parametric index called Nutritional Septicemic Risk (NSR) was applied to all. NSR = 14.265 - 1.764 + Albumin - 1.472 x risk area The criteria that were considered to indicate Proteic Caloric Malnutrition (PCM) were the presence of a Usual Weight Percentage (UW%) lower than 90% and an albumin level lower than 3.5 g/dl. Transfusions were indicated at Hemoglobin levels lower than 10 g/dl and/or a Hematocrit lower than 30%. The perioperative transfusion was defined as that which took place within three weeks prior to the surgery, during the surgery itself, and that which took place during the first 48 hours postoperatively. The postoperative infections have qualitatively been evaluated as: infection of the surgical wound, intraabdominal abscess, and respiratory infection. A total of 80 patients (38.6%) showed some degree of malnutrition. With regard to the transfusions, 55 patients (26.6%) underwent a transfusion. The univariable study has identified the nutritional status as classified according to the NSR multi-parametric index, neoplastic disease, perioperative transfusion and a surgical intervention time greater than two hours, as being risk factors of infection. By means of the logistic regression study, the nutritional status (NSR score) and the perioperative transfusions have been identified as independent risk factors.

A randomized double-blind clinical trial of two antivenoms in patients bitten by Bothrops atrox in Colombia. The Regional Group on Antivenom Therapy Research (REGATHER)

A randomized double-blind clinical trial in 39 patients envenomed by Bothrops atrox in Antioquia and Chocó, Colombia, was performed to compare the efficacy and safety of 2 equine-derived antivenoms prepared at Instituto Clodomiro Picado, University of Costa Rica. Twenty patients received a monovalent anti-B. atrox antivenom (group A) and 19 patients were treated with a polyvalent (Crotalinae) antivenom (group B). Both antivenoms were equally efficient in the neutralization of the most relevant signs of envenoming (haemorrhage and blood clotting time alteration). Fourteen patients (36%) presented early adverse reactions to antivenoms and no significant difference between the 2 groups was observed. Urticaria (18%) was the most frequent early adverse reaction and there was no life-threatening anaphylactic reaction. Based on clinical criteria and serum venom levels, estimated by an enzyme immunoassay, 15 patients were classified into 2 groups: mild and moderate/severe envenoming. With the antivenom doses used in this study (3, 6 and 9 vials for mild, moderate and severe envenoming, respectively), both antivenoms were equally efficient in clearing serum venom levels within the first hour of treatment, and the levels remained below the lower limit of venom detection for 24 h. Antivenom concentration in serum remained high for up to 24 h after antivenom infusion, suggesting that an excess of antibody in relation to circulating antigen had been administered.

[Peroperative transfusion and postoperative infections in patients with benign pathology of the digestive tract]

A prospective study of 136 patients submitted to elective surgery for benign digestive tract pathology, submitted to elective surgery, has been done to evaluate the influences of the nutritional state and the perioperative transfusions on the development of postoperative infections. All patients were given a nutritional evaluation protocol based on anthropometric parameters, analytical data and delayed-type hypersensitivity skin tests (DHST). The criteria for undernourishment were a standard weight percentage lower than 90% and/or an albumin level lower than 3.5 g/dl. Transfusion indication was established at hemoglobin levels lower than 10 g/dl and/or hematocrit values below 30% with perioperative transfusion being considered as that which took place within three weeks prior to the surgery, that taking place during the surgery, and that which took place within the first 48 postoperative hours. The infections were qualitatively evaluated as wound infection, intraabdominal infection and respiratory infection, and quantitatively by means of the Elebeute and Stoner index. 32 of the patients (23.5%) presented undernourishment, and 18 of the patients (13.2%) were transfused. A total of 20 patients (14.7%) presented a postoperative infection. A significant association between under nourishment and infection has been shown (p =), as between transfusion and undernourishment (p < 0.001). Finally, we confirm that the combination of the factors undernourishment and transfusion leads a significance increase (f = 28,462, p < 0.001) of infectious complications.

[The role of multiparameter indices in preoperative nutritional assessment]

The consequence of malnutrition in surgical patients is an increase in post-operative complications. Detection of alteration in the nutritional state is a target in surgery theatres, using a variety of methods, notably anthropometry, analytic protein calculation, and delayed hypersensitivity cutaneous trials, which provide and objective assessment of the different body behaviors. A drawback is the large number of calculations required per patient, so that there is a limited number of patients with all the normal tests. To improve results in predicting complications in surgical patients based on nutritional parameters, the use is proposed of Multiparametric Nutritional Indices, obtained from the joint valuation of those parameters, by using multivariable statistical calculation techniques. The main indices in the literature are described. Multiparametric Indices are useful and easily calculated for the nutritional screening of surgical populations.

[The prediction of postoperative septic complications by means of nutritional parameters. II. The verification of the predictive formula]

An assessment was made of the predictive capacity of the following predictive formulation named Nutritional Sepsis Risk: NSR = 14.26 - 1.76 (albumin) - 1.47 (risk area) This was done in a sample of 65 surgery patients with digestive pathology who were candidates for selective surgery. All had undergone a pre-operative nutritional evaluation program, based on anthropometric and analytical data and Retarded Hypersensitivity Cutaneous Tests (RHCT). NSR was calculated pre-operatively. Infections were assessed qualitatively and quantitatively using Elebeute and Stoner's sepsis index. There were a total of five post-operative infections (7.69%). The NSR intersection point was calculated with an ROC curve, situated in a score of 3. The NSR detected the five infections, so is 100% sensitive, with 70% specificity and, in the detection of the septic risk population, surpassed the other nutritional parameters, whether anthropometric or analytical, and the RHCTs, when they were studied individually.

[The prediction of postoperative septic complications via nutritional parameters. I. The prognostic formulation]

A study has been made of the influence of the nutritional situation on post-operative infections in a sample of 217 patients. A nutritional evaluation file was prepared for each of them, based on anthropometric and analytical tests and delayed hypersensitivity skin tests (PCHR) during the first 24 hours of hospital admission. The criteria whereby a post-operative infection was considered to be present were surgical wound infection, intra-abdominal infection, pneumonia and post-operative fever of 38.5 degrees C or more without a demonstrable septic focus. They were also evaluated quantitatively using Elebeute and Stoner's sepsis index. In the study of the anthropometric parameters, the relation was noted between the body mass index (BMI) and usual weight Percentage (HW%), and septic risk areas (RA) were defined, as a new anthropometric data. A total of 33 patients (15.2%) showed some type of post-surgical infection, manifested in this group by an alteration of the nutritional state revealed by a lower BMI, increased weight loss, a lower albumin rate than in the control group. The septic prognostic value of the RAS is confirmed: no relation was found between septic complications and the PCHR. Finally a multiple regression procedure was prepared between the Elebeute and Stoner sepsis index and all the nutritional parameters studied, to give the following nutritional sepsis risk prognosis index (RSN): NSR = 14,265 - 1,764 x Albumin - 1,427 x Risk Area.

[The nutritional status and immunological situation of cancer patients]

A study was performed on the nutritional state of a sample of 138 patients with digestive and extradigestive neoplasias. The study protocol was based on anthropometric, analytical and immunological tests. The main criteria for malnutrition were as follows: loss of 10% or more in normal weight and/or albumen levels of less than 3.5 gr/dl. A global malnutrition percentage of 56.5% was obtained. The highest malnutrition percentages were found among patients with neoplasia of the oesophagus (78.9%) and the lowest in neoplasias of the breast (9.1%). From the nutritional standpoint, neoplasias of the rectum showed an extradigestive behaviour, with a low malnutrition percentage (40%) compared to digestive tumors. The global malnutrition level for the sample studied was 56.6%. The muscular compartment was the most affected in cases of malnutrition. In the PCHR results, no evidence of the effect of the nutritional state on the alteration of these was recorded (Chi 2 = 6.42, p = 0.207).

[Preoperative nutritional assessment: a 1-year experience]

A study was made of 443 surgical patients using a standard protocol for nutritional evaluation based on anthropometrical, analytical and immunological tests. The main criteria used for considering the presence of malnutrition was a weight loss of 10% and/or seric albumin level of less than 3.5 g/dl., by which method four nutritional groups were established. The average age of the sample was 56 +/- 15 years and 35% of patients had neoplasias, 9.25% of patients were classified as belonging to Group A (weight loss and low albumin levels), 10.15% as group B (low albumin levels), 14.44% as group C (weight loss), and 66.16% as group D (normal), so that the global malnutrition percentage was 33.84%. The Body Mass Index (BMI) and Ideal Weight Percentage (% IWP) were of similar importance, and there was a significant alteration in the Triceps Skin Fold (% TSF) and Muscular Area Percentage of the arm (% MAP) when malnutrition was in evidence. In the study of the Delayed Hypersensitivity Skin Tests (DSST) 21.4% showed anergia, 15.8% hypoergia and 62.8% were reactive, with a reduction in reactivity in the case of malnutrition. This was the parameter that most affected the albumen level.

[Variability of anthropometric parameters]

Presentation of a comparative study of four ideal weight tables applied to the same population, in order to evaluate the differences or similarities between the same. Significant differences (p<0.001) were found between the four tables studied (WHO, USA, Barcelona, Tenerife) when classifying a patient into one of the three groups defined (malnutrition, normal and obese). The maximum differences found were between the Barcelona and Tenerife tables, which classified 13,7% and 24.05% respectively as cases of malnutrition and 35.9% and 16.89% respectively as obese.

[Incidence of malnutrition in a surgery department]

Presentation of a description of the initial results obtained in nutritional evaluation of patients admitted for elective surgery during a 6-month period. A total of 212 patients were studied, recording malnutrition in 25%. This was severe in half of the cases. As a result of the malnutrition, a significant reduction was observed in the number of positive responses to the Multitest and the total count of lymphocytes.

[Immunologic consequences of malnutrition: assessment with multitest]

Presentation of a clinical study of 256 patients eligible for elective surgery, with the purpose of evaluating the immunological consequences of malnutrition. With this aim, retarded hypersensitivity skin tests were performed. The malnutrition criteria used included 10% normal weight loss and/or seric albumin levels of less than 3.5 g/dl. There were 99 patients in total (38.67%) with malnutrition criteria. Within this group 21.79% showed positive responses compared to 38.88% of control group (p less than 0.001). The "average papule" in the group suffering from malnutrition was 4.18 +/- 2.06 and in the control group, 3.64 +/- 2.20 (p less than 0.001), with a significant increase in tuberculine papule in the group with malnutrition.