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1.
S Afr Med J ; 114(5): e1081, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-39041468

RESUMEN

BACKGROUND: Caesarean section is a life-saving procedure which is associated with high rates of maternal and neonatal complications. It has been estimated that globally, 29.7 million births occur by caesarean section annually. The risk of postpartum infection is estimated to be five to ten times higher compared to normal vaginal delivery. Pregnancy-related sepsis was listed as a top six cause of maternal mortality in the South African Saving Mothers report between 2017 and 2019. Multiple trials have been conducted in an attempt to optimise administration of prophylactic antibiotics in an effort to reduce postpartum infection and maternal sepsis, and current practice guidelines suggest that there is sufficient evidence that extended spectrum antibiotics, in combination with kefazolin, result in reduction of postpartum infections Objectives. To investigate the effect of perioperative administration of kefazolin alone compared to kefazolin plus metronidazole on postpartum infection in women undergoing caesarean section at Kalafong Provincial Tertiary Hospital. METHOD: All patients undergoing emergency or elective caesarean section were randomised and then sequentially numbered in opaque sealed envelopes, which were placed in the caesarean section operating theatre. The intervention group received kefazolin and a sealed envelope with metronidazole. The control group received kefazolin and a sealed envelope with normal saline. RESULTS: A total of 57/1 010 patients (5.64%) had surgical site infections, of which 27 (5.33%) were in the control group, and 30 (5.96%) were in the intervention group (p=0.66). Two patients in each arm (0.40% in the intervention arm and 0.39% in the control arm) underwent laparotomy procedures, while three women (0.60%) in the intervention arm and four women (0.79%) in the control arm underwent hysterectomy procedures. There were no statistically significant differences in all the measured secondary outcomes between the two groups. CONCLUSION: The overall sepsis rate in this study was 5.64%. Postpartum infection is multifactorial and there are multiple factors that can be addressed in strengthening the sepsis care bundle. We do not recommend the addition of metronidazole to kefazolin as prophylaxis at caesarean section.


Asunto(s)
Profilaxis Antibiótica , Cesárea , Metronidazol , Humanos , Femenino , Embarazo , Cesárea/efectos adversos , Adulto , Metronidazol/uso terapéutico , Profilaxis Antibiótica/métodos , Sudáfrica/epidemiología , Antibacterianos/uso terapéutico , Antibacterianos/administración & dosificación , Infección Puerperal/prevención & control , Infección Puerperal/epidemiología , Quimioterapia Combinada , Infección de la Herida Quirúrgica/prevención & control , Infección de la Herida Quirúrgica/epidemiología
2.
S Afr Med J ; 114(6): e1081, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-39041508

RESUMEN

BACKGROUND: Caesarean section is a life-saving procedure which is associated with high rates of maternal and neonatal complications. It has been estimated that globally, 29.7 million births occur by caesarean section annually. The risk of postpartum infection is estimated to be five to ten times higher compared with normal vaginal delivery. Pregnancy-related sepsis was listed as a top-six cause of maternal mortality in the South African Saving Mothers report between 2017 and 2019. Multiple trials have been conducted in an attempt to optimise administration of prophylactic antibiotics in an effort to reduce postpartum infection and maternal sepsis, and current practice guidelines suggest that there is sufficient evidence that extended-spectrum antibiotics, in combination with kefazolin, result in reduction of postpartum infections. OBJECTIVES: To investigate the effect of perioperative administration of kefazolin alone compared with kefazolin plus metronidazole on postpartum infection in women undergoing caesarean section at Kalafong Provincial Tertiary Hospital, Pretoria, South Africa. METHOD: All patients undergoing emergency or elective caesarean section were randomised and then sequentially numbered in opaque sealed envelopes, which were placed in the caesarean section operating theatre. The intervention group received kefazolin and a sealed envelope with metronidazole. The control group received kefazolin and a sealed envelope with normal saline. RESULTS: A total of 57/1 010 patients (5.64%) had surgical site infections, of which 27 (5.33%) were in the control group, and 30 (5.96%) were in the intervention group (p=0.66). Two patients in each arm (0.40% in the intervention arm and 0.39% in the control arm) underwent laparotomy procedures, while three women (0.60%) in the intervention arm and four women (0.79%) in the control arm underwent hysterectomy procedures. There were no statistically significant differences in all the measured secondary outcomes between the two groups. CONCLUSION: The overall sepsis rate in this study was 5.64%. Postpartum infection is multifactorial and there are multiple factors that can be addressed in strengthening the sepsis care bundle. We do not recommend the addition of metronidazole to kefazolin as prophylaxis at caesarean section.


Asunto(s)
Antibacterianos , Profilaxis Antibiótica , Cesárea , Metronidazol , Humanos , Femenino , Metronidazol/administración & dosificación , Embarazo , Profilaxis Antibiótica/métodos , Adulto , Sudáfrica , Antibacterianos/administración & dosificación , Cuidados Preoperatorios/métodos , Infección de la Herida Quirúrgica/prevención & control , Infección de la Herida Quirúrgica/epidemiología , Quimioterapia Combinada , Infección Puerperal/prevención & control
3.
J Phys Condens Matter ; 36(24)2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38437717

RESUMEN

We present temperature-dependent single-crystal diffraction results on seven antifluorite-typeA2MeX6compounds withMe= Os or Ir: K2OsCl6,A2OsBr6withA= K, Rb, Cs and NH4, and K2IrX6withX= Cl and Br. The structural transitions in this family arise fromMeX6octahedron rotations that generate a rich variety of symmetries depending on the rotation axis and stacking schemes. In order to search for local distortions in the high-symmetry phase we perform refinements of anharmonic atomic displacement parameters with comprehensive data sets. Even at temperatures close to the onset of structural distortions, these refinements only yield a small improvement indicating only small anharmonic effects. The phase transitions in these antifluorites are essentially of displacive character. However, some harmonic displacement parameters are very large reflecting soft phonon modes with the softening covering large parts of the Brillouin zone. The occurrence of the rotational transitions in the antifluorite-type family can be remarkably well analyzed in terms of a tolerance factor of ionic radii.

4.
Internet Interv ; 35: 100723, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38370289

RESUMEN

Background: Internet-based interventions offer a way to meet the high demand for psychological support. However, this setting also has disadvantages, such as the lack of personal contact and the limited ability to respond to crises. Blended care combines Internet-based interventions with face-to-face psychotherapy and merges the benefits of both settings. To ensure the uptake of blended care in routine care, Internet-based interventions need to be suitable for different therapeutic approaches and mental disorders. Objective: This paper describes the participatory development process of the Internet-based intervention "TONI" using a common therapeutic language and content on various transdiagnostic topics to be integrated into routine outpatient psychotherapy. Methods: To develop this intervention in a participatory manner, we followed the Integrate, Design, Assess, and Share (IDEAS) framework. In a multilevel development process, we used a combination of interviews, focus groups, and proofreading to optimally tailor online modules to routine outpatient psychotherapy. Building on well-established cognitive-behavioral online content, we included expert interviews with psychodynamic (n = 20) and systemic psychotherapists (n = 9) as well as focus groups with psychotherapists of different approaches (n = 10) and persons with lived experience of mental illness (PWLE; n = 10). Results: We describe the development process of TONI step-by-step, outlining the specific requirements that therapists from different therapeutic approaches as well as PWLE have and how we implemented them in our intervention. This includes the content and specific exercises in the online modules, aspects of data protection, language, design, and usability. Conclusion: Internet-based interventions that use a common therapeutic language and address therapeutic principles across different approaches have the potential to advance digitalization in psychotherapy. Involving psychotherapists and PWLE in intervention development may positively impact acceptance and usage in practice. This study shows how participatory intervention development involving both psychotherapists and PWLE can be carried out.

5.
Rev. otorrinolaringol. cir. cabeza cuello ; 83(2): 166-170, jun. 2023. ilus
Artículo en Español | LILACS | ID: biblio-1515475

RESUMEN

La parálisis o paresia facial alternobárica es una neuropraxia del séptimo nervio cra-neal debido a cambios de presión. Se produce en el contexto de una disfunción de la trompa de Eustaquio, una dehiscencia canal del nervio facial y cambios en la presión atmosférica. Se considera una rara complicación de barotrauma. Su prevalencia es difícil de estimar y, probablemente, se encuentre subreportada. La forma de presentación más habitual incluye paresia facial, plenitud aural, hipoacusia, otalgia, parestesias faciales y linguales. La mayoría de los episodios son transitorios, con una duración entre minutos y algunas horas, con recuperación posterior completa. Entre los diagnósticos diferenciales se encuentran causas periféricas y centrales de paresia facial, las cuales hay que sospechar ante la persistencia de los síntomas en el tiempo o ante la presencia de otros signos o síntomas neurológicos. La evaluación inicial debe incluir un examen otoneurológico completo. La tomografía computarizada de hueso temporal favorece la visualización de posibles dehiscencias del canal del facial. La prevención de nuevos episodios incluye la práctica de ecualización efectiva, la resolución de la disfunción de la trompa de Eustaquio y en algunos casos específicos, métodos alternativos de ventilación del oído medio como la colocación de tubos de ventilación. Una vez instalada la parálisis facial, si no se produce recuperación espontánea, el uso de corticoides es una opción. Se presenta un caso de paresia facial alternobárica recurrente y una revisión de literatura.


Alternobaric facial palsy or paralysis is a neuropraxia of the seventh cranial nerve due to pressure changes. It occurs in the context of Eustachian tube dysfunction, facial nerve canal dehiscence, and changes in atmospheric pressure. It is considered a rare complication of barotrauma. Its prevalence is difficult to estimated, and this condition is probably underreported. The most common form of presentation includes facial weakness, ear fullness or pressure, hearing loss, otalgia, facial and lingual paresthesias. Most episodes are transient, lasting from minutes to a few hours, with a subsequent complete recovery. Among the possible differential diagnoses are peripheral and central causes of facial paralysis, which must be suspected due to the persistence of symptoms over time or the presence of other neurological signs or symptoms. The initial evaluation should include a complete otoneurological examination. Computed tomography of the temporal bone is useful for the visualization of facial canal dehiscence. Prevention of further episodes includes practicing effective equalization, Eustachian tube dysfunction treatment, and in certain specific cases, alternative middle ear ventilation methods such as tympanostomy tubes. Once facial paralysis is established, if spontaneous recovery does not occur, the use of corticosteroids is considered an option. A case of recurrent alternobaric facial paresis and a review of the literature are presented.


Asunto(s)
Humanos , Femenino , Persona de Mediana Edad , Parálisis Facial/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Potenciales Evocados
6.
Artículo en Inglés | AIM (África) | ID: biblio-1272250

RESUMEN

Background: Obesity changes body composition including fat free mass (FFM), regarded as the "pharmacologically active mass". Scaling drug doses to obese patients by total body mass (TBM) results in overdose. We aimed to determine the success rate of inducing anaesthesia in normal, overweight and obese patients with propofol, using an adjusted body mass scalar (ABM), which embodies the increased FFM of obese patients. Methods: Ninety-six patients were divided into three groups according to body mass index (BMI): normal, overweight and obese. Propofol 2 mg/kg ABM was administered according to the equation: ABM = IBM + 0.4(TBM ­ IBM), where IBM = ideal body mass. Induction success was assessed clinically and by electroencephalographic spectral entropy. Results: The groups were similar regarding gender, age, height and IBM. One patient was morbidly obese (BMI = 44). State entropy (SE) decreased to < 60 in 33/33, 28/29 and 33/34 patients in the normal-weight, overweight and obese groups respectively, an overall success rate of 97.5% (95% confidence interval 92.7% to 99.4%). Median lowest achieved SE values and median times that SE remained < 60 did not differ between groups, however the individual values ranged widely in allthree groups. Induction failed in the two patients whose SE did not decrease to < 60 (one overweight and one obese). Conclusions: The ABM-based propofol induction dose has a high success rate in normal, overweight and obese patients. Further studies are required to determine the feasibility among morbidly obese patients


Asunto(s)
Composición Corporal , Índice de Masa Corporal , Obesidad , Propofol
8.
S. Afr. respir. j ; 22(1): 3-6, 2016.
Artículo en Inglés | AIM (África) | ID: biblio-1271292

RESUMEN

Introduction. Severe pneumonia in infants who are HIV-infected is a common problem in many parts of the developing world; especially sub-Saharan Africa. What has been missing from previous studies of severe pneumonia in HIV-infected infants; however; is a description of the host inflammatory response and cytokine/chemokine profile that accompanies this disease. Objective. To describe the cytokine profiles associated with severe hypoxic pneumonia in HIV-infected infants Methods. In a cohort of HIV-infected children diagnosed clinically with severe hypoxic pneumonia; paired serum and sputum cytokines were tested. A control group of HIV-infected children with bronchiectasis contributed matching controls.Results. A total of 100 infants (mean age 2.8 months) with a clinical diagnosis of severe hypoxic pneumonia were included in this study. IP-10 was markedly elevated in both sputum (mean 560.77pg/ml) and serum (mean 9091.14pg/ml); while IP-10 was elevated in serum (mean 39.55 pg/ml); with both these cytokines being significantly higher than in stable children with HIV-related bronchiectasis. Conclusion. This study of HIV-infected infants with severe hypoxic pneumonia suggests that IL-10 and IP-10 are associated with more severe lung disease. However; further investigation of this association is required


Asunto(s)
Citocinas , Infecciones por VIH , Lactante , Neumonía
10.
S. Afr. fam. pract. (2004, Online) ; 52(2): 142-148, 2010.
Artículo en Francés | AIM (África) | ID: biblio-1269878

RESUMEN

Background:Statistics around the world show a rapid increase in HIV infection in the older population. Many older women remain sexually active and are therefore exposed to heterosexual transmission of HIV infection. Older women are most likely considered respected opinion leaders within the families and communities and are likely to influence others' attitudes and behaviours. An increase in knowledge through information plays a fundamental role and is a prerequisite for behavioural change that may prevent new HIV infections. The purpose of the current study was to assess the knowledge and misconceptions regarding the spread and prevention of HIV in older women attending the Tshwane District Hospital (TDH) in South Africa. Methods: A prospective cross-sectional study of 100 women; aged 50 to 80 years; attending the TDH out-patient section during November and December 2006 was done. The levels of knowledge were determined by using a directed questionnaire. Results: Eight per cent of the participants answered all the questions correctly; showing knowledge gaps in the remaining 92(95confidence interval: 86.7-97.3). Many participants were unaware of the protective effects of condom use; especially female condoms; and of HIV spread by anal transmission; the sharing of needles and blood transfusion. Three or more misconceptions were present in 48of the participants; such as HIV spread by casual contact; the sharing of personal items; air-borne infection; mosquito bites; HIV testing and AIDS prevention or cure by traditional medicines or alternatives. Sixty-two per cent of the older women were found to have adequate knowledge (95confidence interval: 52-71.5); knowing the basic concepts regarding HIV transmission.Conclusion: There is a significant need for HIV-related preventive health education in older women; not only to decrease potential high-risk behaviours; but also to reduce unnecessary feelings of anxiety and misconceptions. Family physicians; due to their unique role; might be able to use the present study in their practices in order to optimise the planning and structuring of awareness interventions and prevention programmes


Asunto(s)
Infecciones por VIH/prevención & control , Conocimiento , Malentendido Terapéutico , Población Urbana , Mujeres
11.
S. Afr. j. sci. (Online) ; 105(1-2): 68-72, 2010.
Artículo en Inglés | AIM (África) | ID: biblio-1270887

RESUMEN

A disproportionately large number of young (50 years); those from young black patients presented more often with a low methylation phenotype (CIMP-L) and high levels of microsatellite instability (MSI-H). Furthermore; as determined by real-time PCR using probe technology; the tissues from35of young blacks showed mutations within exon 1 of the KRAS gene. The BRAF-V600E mutation was only evident in the case of a single young black patient. Based on these results it seems likely that a proportion of CRC cases in young black patients from South Africa develop through the accumulation of mutations resulting in a mismatch repair deficiency linked to MSI-H and; possibly; germline mutations in the mismatch repair genes. The features in these patients are consistent with a diagnosis of the Hereditary Non-Polyposis Colorectal Cancer (HNPCC) syndrome. This finding has important implications for patient management and suggests that family members may be at high risk for CRC


Asunto(s)
Población Negra , Neoplasias Colorrectales , Adulto Joven
12.
S. Afr. med. j. (Online) ; 99(2): 103-106, 2009.
Artículo en Inglés | AIM (África) | ID: biblio-1271284

RESUMEN

Background. Colorectal carcinoma (CRC) has a low incidence among the black African population. Largely unrecognised in the scientific literature is the fact that a disproportionately large number of young black patients (50 years old) present with CRC. Objectives. To analyse those tumours; which we propose may link them to morphological features associated with known genetic pathways. Methods. A retrospective review of South African patients histologically diagnosed as having CRC by the Division of Anatomical Pathology; National Health Laboratory Service (NHLS) and the University of the Witwatersrand (1 732 patients from 1990 to 2003). The histology was fully reviewed in 609 patients (1997 - 2002); and all specimens from patients 50 years of age were subjected to immunohistochemistry tests for mismatch repair proteins; as well as APC and p53 proteins. Results. Most young patients (50 years) were black (41v. 10white; p=0.001). Blacks had predominantly proximal tumours and significantly more poorly differentiated and/or mucinous tumours (p=0.006); and loss of mismatch repair protein expression was more evident than in whites. Conclusions. It seems likely that CRC in young blacks develops through the accumulation of mutations; most probably via mis- match repair deficiency or promoter methylation; which in turn is linked to poor differentia- tion and a mucinous architecture


Asunto(s)
Población Negra , Neoplasias Colorrectales , Adulto Joven
13.
14.
S. Afr. j. sports med. (Online) ; 20(1): 28-31, 2008.
Artículo en Inglés | AIM (África) | ID: biblio-1270917

RESUMEN

OBJECTIVE. Athletes frequently report training to music; yet there have been relatively few studies that have addressed the benefit of exercising with music. Design. Volunteer men and women (N=30); aged between 18 and 40 years; performed an initial familiarisation session. Part of this session involved the measurement of maximal oxygen consumption. With at least a 48-hour intervening period; this was then followed by a first 20-minute submaximal cycling session; at 80of maximal oxygen consumption. At least 48 hours later a second submaximal cycling session was performed. Subjects were randomly divided into two groups. Group A cycled without music and group B cycled with music for the first submaximal cycling session. Subjects underwent the same testing procedure for the second submaximal cycling session; but this time group A cycled to music and group B cycled without music. Subjects served as their own controls. SETTING. The study was performed in the physiology exercise laboratory; at the University of the Witwatersrand. MAIN OUTCOME MEASURES. During the submaximal sessions heart rate; perceived exertion (Borg scale) and plasma lactate concentration were assessed. Subjects completed a post-test questionnaire once both submaximal cycling sessions were completed. RESULTS. There were no significant differences in physiological variables (change in plasma lactate and heart rate); nor were there any significant differences in Borg scale ratings when the subjects cycled with and without music. However; according to the post-test questionnaire 67of subjects identified the cycling session with music to be easier than the session without music. CONCLUSION. Listening to music while performing submaximal cycling resulted in no physiological benefit. Yet; the cycling session done in conjunction with music was deemed; by the majority of the subjects; to be easier than the cycling session without music


Asunto(s)
Música , Educación y Entrenamiento Físico/métodos , Deportes
15.
Cardiovasc. j. Afr. (Online) ; 19(3): 141-144, 2008.
Artículo en Inglés | AIM (África) | ID: biblio-1260379

RESUMEN

Aim : Ischaemia-modified albumin (IMA); as measured by the albumin-cobalt binding (ACB) testr; has been cleared by the US Food and Drug administration as a biomarker to exclude the presence of myocardial ischaemia in patients. Although there are a number of published studies detailing the clinical utility of IMA; data on the biological variation of IMA are still lacking. In this study we determined the analytical and biological variance components of ischaemia-modified albumin; and compared the distribution of IMA values in our patient population to those provided by the kit manufacturer. Methods : IMA was determined once a week for five consecutive weeks on a cohort of healthy subjects using a colorimetric method; the ACB testr on a Roche modular analyser. Results : The analytical coefficient of variation (CVA) was 5; and the within-subject (CVI) and between-subject (CVG) biological variations were 3 and 7; respectively. Analysis of the repeated measures with gender and race (black and Caucasian) as between-subject factors; and weeks (1-5) as the within-subject factor showed that gender had no significant effect on circulating IMA concentrations (p = 0.3146); whereas race did have a significant effect (p = 0.0062). A significant (p = 0.0185) interaction was observed between gender and race. Conclusion : The ACB testr could bring a new dimension to the care and management of patients with acute coronary syndrome. Further studies for normal population distributions by gender and ethnicity; and an optimum cut-off value appear to be required


Asunto(s)
Albúminas , Biodiversidad , Isquemia
16.
Health SA Gesondheid (Print) ; 12(1): 3-11, 2007.
Artículo en Inglés | AIM (África) | ID: biblio-1262381

RESUMEN

Research has proven that developmentally supportive care (DSC) improves the developmental outcomes for preterm infants. Available evidence regarding the similar effect of one of its principles; developmentally supportive positioning (DSP); was inconclusive; which lead to this study. The study was conducted in two phases: firstly; the Hennessy Stress Scale for the Preterm Infant was developed and; secondly; using a within-subject design; the effects of DSP n the stress levels of preterm infants were measured. Using the Hennessy Stress Scale for the Preterm Infant; observed qualitative data could be quantified to reflect the infant's stress levels as a percentage. Nonprobability sampling was used to select twenty-two preterm infants of gestational age 37 weeks. The stress levels of these infants; who were admitted to a specific neonatal intensive care unit and not sedated; were observed before and after the implementation of DSP; and were then quantified; and recorded. The pre-test (infants without DSP) and post-test (same infants with DSP) mean stress level scores were 29.07 vs. 16.87 (mean shift of 12.2 and standard deviation of 3.97); which were significantly different (p 0.0001; Student's paired t-test). The conclusion was that DSP significantly decreases premature infants' stress levels


Asunto(s)
Nacimiento Prematuro , Estrés Fisiológico
17.
Artículo en Inglés | AIM (África) | ID: biblio-1272223

RESUMEN

Background and Aim: Recently an electroencephalographic (EEG) spectral entropy module (M-ENTROPY) for an anaesthetic monitor has become commercially available. We compared its performance as an indicator of the state of anaesthesia with that of an older conventional quantitative EEG (QEEG) module (M-EEG) by the same manufacturer (Datex-Ohmeda Division; Instrumentarium Corp.; Helsinki; Finland). Methods: There were 40 ASA class I or II subjects; aged between 16-60 years; who underwent elective abdominal surgery. EEG data were collected from the printouts of the respective modules. The data presented here were related to four levels of anaesthesia: Pre-anaesthetic wakefulness (state A); 2 sevoflurane endtidal (ET) concentration after completion of surgery (state B); low ET sevoflurane concentrations (~ 0.5) just prior to regaining responsiveness (state C); and post-anaesthetic responsiveness (state D). Results: In terms of the prediction probability (Pk statistic); response entropy (RE) and state entropy (SE) produced higher values (0.95-1.0) than the best performing QEEG variable; frontal amplitude (0.86-0.95). Only RE scores did not overlap between states A and B or between B and D. The misclassification of subjects between states C and D was far lower for RE (28) than for any of the conventional QEEG measures (90). Conclusion: In on-line monitoring spectral entropy is superior in distinguishing states of anaesthesia and is also easier to use than conventional QEEG. It is speculated that the artefact rejection strategies accorded spectral entropy might significantly benefit conventional QEEG analysis

18.
Acta amaz ; 27(1)1997.
Artículo en Portugués | LILACS-Express | LILACS, VETINDEX | ID: biblio-1454601

RESUMEN

Lecythidaceae comprise one of the four most common tree families in the Amazon forest, but there have been few studies of vesicular-arbuscular mycorrhizae in this taxon. In this study roots of 31 species in six genera of Lecythidaceae were collected in a primary forest on an acid oxisol. No vesicular-arbuscular mycorrhizae, as indicated by the presence of vesicles or arbuscules were detected. Only some hyfas were found on some species roots, but not enough for increasing the nutrient absorption from the soil. This indicated that under the edaphic condiction and the time which the samples were collected, these species worked as no mycor-rhizal plants. These informations confirm datas found for other researches, and may be important for exploring more efficiently and by a not predatory way, the species of Lecythidaceae on agroforestry systems in the Amazon.


As Lecythidaceae compreendem uma das quatro famílias de árvores mais abundantes na floresta amazônica, mas foram pouco estudadas no que sc refere à simbiose com fungos micorrízicos dos solos. Foram coletadas raízes de 31 espécies de seis gêneros desta família numa floresta de terra firme da Amazônia Central, próxima a Manaus, sob um latossolo amarelo. Em algumas espécies observou-se uma ausência total de fungos nas raízes, enquanto que em outras, apenas algumas hifas de fungos, mas sem vesículas ou arbúsculos, estruturas que serviriam para confirmar a presença de micorrizas vesículo-arbusculares efetivas nas mesmas. As poucas bifas encontradas não seriam suficientes para aumentar a absorção de nutrientes do solo, indicando que nas condições edáficas e épocas de coletas do presente estudo, as plantas se comportaram como não micorrizicas. Estas informações reforçam dados obtidos por outros autores e podem servir de embasamento para uma exploração mais eficiente e não predatória de espécies desta família em sistemas agroflorestais na Amazônia.

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