Endoscopic endonasal surgery to treat intrinsic brainstem lesions: correlation between anatomy and surgery

OBJECTIVE

The endoscopic endonasal approach (EEA) has been proposed as an alternative in the surgical removal of ventral brainstem lesions. However, the feasibility and limitations of this approach to treat such pathologies are still poorly understood. This study aimed to report our experience in five consecutive cases of intrinsic brainstem lesions that were managed via an EEA, as well as the specific anatomy of each case.

METHODS

All patients were treated in a single center by a multidisciplinary surgical team between 2015 and 2019. Before surgery, a dedicated anatomical analysis of the brainstem safe entry zone was performed, and proper surgical planning was carried out. Neurophysiological monitoring was used in all cases. Anatomical dissections were performed in three human cadaveric heads using 0° and 30° endoscopes, and specific 3D reconstructions were executed using Amira 3D software.

RESULTS

All lesions were located at the level of the ventral brainstem. Specifically, one mesencephalic cavernoma, two pontine ca- vernomas, one pontine gliomas, and one medullary diffuse midline glioma were reported. Cerebrospinal fluid leak was the major complication that occurred in one case (medullary diffuse midline glioma). From an anatomical standpoint, three main safe entry zones were used, namely the anterior mesencephalic zone (AMZ), the peritrigeminal zone (PTZ, used in two cases), and the olivar zone (OZ). Reviewing the literature, 17 cases of various brainstem lesions treated using an EEA were found.

CONCLUSIONS

To our knowledge, this was the first preliminary clinical series of intrinsic brainstem lesions treated via an EEA presented in the literature. The EEA can be considered a valid surgical alternative to traditional transcranial approaches to treat selected intra-axial brainstem lesions located at the level of the ventral brainstem. To achieve good results, surgery must involve comprehensive anatomical knowledge, meticulous preoperative surgical planning, and intraoperative neurophysiological moni- toring.

Porphyromonas gingivalis W83 traffics via ICAM1 in microvascular endothelial cells and alters capillary organization in vivo

Objective: Microvascular dysfunction is a feature of periodontal disease. P. gingivalis, one of the most common oral bacteria present in gingival tissue biofilms, has also been identified in the gingival capillaries of patients with chronic periodontitis. We sought to determine the effect of P. gingivalis W83 infection on microvascular endothelium in vivo and in vitro. Methods and Results: Interdental papillae of rats with P. gingivalis-induced alveolar bone loss had a more dilated and denser subepithelial capillary network than uninfected controls. P. gingivalis W83 was detected in the epithelial layers, the subepithelial connective tissue matrix, and subgingival capillaries. P. gingivalis invaded human dermal microvascular endothelial cells (HD-MVECS) and persisted up termination (24 h). Colocalization analysis at 2.5, 6, and 24 h post-inoculation showed that 79-88% of internalized bacteria were in ICAM-1 positive endosomes, and 10-39% were in Rab5, Rab7, or LAMP1 positive compartments, but never in autophagosomes. Antibody-based blockade of ICAM-1 significantly reduced W83 invasion in HD-MVECS. P. gingivalis infected HD-MVECS were unable to form vascular networks in Matrigel. Conclusions: P. gingivalis perturbs microvascular endothelial function and invasion of these cells via ICAM-1 may be important for microbial persistence within tissues.

Perceived and anticipating stigma in schizophrenia in relationship with depressive symptoms and functionality degree

Introduction

Perceived and anticipated stigma is relevant issues in patients with schizophrenia. Stigma has negative consequences both in quality of life and in the course of illness.

Objectives

To analyze the degree of perceived and anticipated stigma and discrimination in patients with schizophrenia and their relationship with clinical and socio-demographic variables.

Methods

A cross-sectional study was carried out in a sample of 100 patients with diagnosis of schizophrenia, 18 or more years old, clinically stabilized, without axis I DSM-IV comorbidity. Patients received treatment in the outpatient services of a catchment area in Madrid. Perceived and anticipated discrimination was evaluated trough the DISC-12 (Discrimination and Stigma scale). Other study variables were: socio-demographic characteristics, symptoms of depression (Calgary Scale) and functionality degree measured by Global Assessment of Function (GAF).

Results

The presence of symptoms of depression evaluated by the Calgary Scale and low degree of functionality measured by GAF are associated with greater feelings of discrimination and stigma, especially in the sub-scales of experienced and anticipated discrimination of the DISC 12. Anticipated stigma is higher in men than in women while the rest sub scales of the DISC-12 do not correlate with gender or other sociodemographic variables.

Conclusions

Preventive strategies to avoid the stigma in schizophrenia should consider some characteristics associated with disease, especially the degree of functionality and presence of depressive symptoms.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Prenatal infection with Mycoplasma pulmonis in rats exaggerates the angiotensin II pressor response in adult offspring

Exposure to different stressors in utero is linked to adult diseases such as obesity and hypertension. In this study, the impact of prenatal infection (PNI) on adult body weight and cardiovascular function was evaluated using a naturally occurring rodent pathogen, Mycoplasma pulmonis (MP). Pregnant Sprague-Dawley rats were infected with MP on gestational day 14 and gave birth naturally. Adult PNI offspring weighed more than controls, but resting mean arterial pressure (MAP) was unchanged. Subcutaneous injection of angiotensin II (10 μg/kg) elicited a rise in MAP that was greater in both male and female PNI offspring compared with controls (P < 0.03). The accompanying reflex bradycardia was similar to the controls, suggesting that PNI induced baroreflex dysfunction. Subcutaneous nicotine administration, a potent cardiorespiratory stimulus, also elicited a transient rise in MAP that was generally greater in the PNI group, but the change in MAP from baseline was only significant in the PNI females compared with controls (P < 0.03). Elevated body weight and cardiovascular reactivity in the PNI offspring was associated with an increase in the ratio of hypothalamic corticotrophin-releasing hormone receptors type 1 to type 2 gene expression in both sexes compared with controls. These findings support previous studies demonstrating that PNI induces alterations in cardiovascular function and body weight. Yet, unlike previous studies utilizing other models of PNI (e.g., endotoxin), MP PNI did not induce resting hypertension. Thus, our study provides a foundation for future studies evaluating the cardiovascular risks of offspring exposed to microbial challenges in utero.

Periodontal Disease and Pregnancy Outcomes: Overview of Systematic Reviews

Periodontal disease is very common during pregnancy. Although it has been linked to adverse pregnancy outcomes, systematic reviews have reached discrepant conclusions on these links. Therefore, we conducted a systematic overview of systematic reviews studying the association between periodontal disease and adverse pregnancy outcomes. We searched 6 online databases up to November 2016 and hand-searched references and citations of eligible papers. Systematic reviews of studies comparing pregnancy outcomes among women with and without periodontal disease were eligible for inclusion. Primary outcomes were maternal mortality, preterm birth, and perinatal mortality. Two reviewers extracted data and assessed risk of bias of individual systematic reviews. Findings are described in tabular and narrative form. Twenty-three systematic reviews (including between 3 and 45 studies) were included. None reported the association between periodontal disease and maternal or perinatal mortality. Systematic reviews with the lowest risk of bias consistently demonstrated positive associations between periodontal disease and preterm birth (relative risk, 1.6; 95% confidence interval, 1.3 to 2.0; 17 studies, 6,741 participants), low birth weight (LBW; relative risk, 1.7; 95% CI, 1.3 to 2.1; 10 studies, 5,693 participants), preeclampsia (odds ratio, 2.2; 95% CI, 1.4 to 3.4; 15 studies, 5,111 participants), and preterm LBW (relative risk 3.4; 95% CI, 1.3 to 8.8; 4 studies, 2,263 participants). Based on these figures, estimated population-attributable fractions for periodontal disease were 5% to 38% for preterm birth, 6% to 41% for LBW, and 10% to 55% for preeclampsia. In terms of limitations, as several primary studies did not adjust for confounding, meta-analyses may have overestimated the strength of the associations under study. Due to substantial overlap in included primary studies, we could not aggregate results across reviews. Consistent evidence from systematic reviews with low risk of bias indicates that pregnant women with periodontal disease are at increased risk of developing preeclampsia and delivering a preterm and/or LBW baby (PROSPERO: CRD42015030132).

Knowledge Transfer Statement: This study highlights that periodontal disease is an important risk factor for several common adverse pregnancy outcomes. Clinicians should be aware of this link to guide risk selection. Research is needed to develop novel preventive and treatment strategies.

Acute lung injury: apoptosis in effector and target cells of the upper and lower airway compartment

Apoptotic cell death has been considered an underlying mechanism in acute lung injury. To evaluate the evidence of this process, apoptosis rate was determined in effector cells (alveolar macrophages, neutrophils) and target cells (tracheobronchial and alveolar epithelial cells) of the respiratory compartment upon exposure to hypoxia and endotoxin stimulation in vitro. Cells were exposed to 5% oxygen or incubated with lipopolysaccharide (LPS) for 4, 8 and 24 h, and activity of caspase-3, -8 and -9 was determined. Caspase-3 of alveolar macrophages was increased at all three time-points upon LPS stimulation, while hypoxia did not affect apoptosis rate at early time-points. In neutrophils, apoptosis was decreased in an early phase of hypoxia at 4 h. However, enhanced expression of caspase-3 activity was seen at 8 and 24 h. In the presence of LPS a decreased apoptosis rate was observed at 8 h compared to controls, while it was increased at 24 h. Tracheobronchial as well as alveolar epithelial cells experienced an enhanced caspase-3 activity upon LPS stimulation with no change of apoptosis rate under hypoxia. While increased apoptosis rate is triggered through an intrinsic and extrinsic pathway in alveolar macrophages, intrinsic signalling is activated in tracheobronchial epithelial cells. The exact pathway pattern in neutrophils and alveolar epithelial cells could not be determined. These data clearly demonstrate that upon injury each cell type experiences its own apoptosis pattern. Further experiments need to be performed to determine the functional role of these apoptotic processes in acute lung injury.

The volatile anaesthetic sevoflurane attenuates lipopolysaccharide-induced injury in alveolar macrophages

Acute lung injury (ALI) is a well-defined inflammation whereby alveolar macrophages play a crucial role as effector cells. As shown previously in numerous experimental approaches, volatile anaesthetics might reduce the degree of injury in pre- or post-conditioning set-ups. Therefore, we were interested to evaluate the effect of the application of the volatile anaesthetic sevoflurane on alveolar macrophages regarding the expression of inflammatory mediators upon lipopolysaccharide (LPS) stimulation in vitro. Alveolar macrophages were stimulated with LPS. Two hours later, cells were exposed additionally to air (control) or to sevoflurane-containing air for 4, 6, 8, 12 or 24 h. Tumour necrosis factor (TNF)-alpha, cytokine-induced neutrophil chemoattractant-1 (CINC-1), macrophage-inflammatory protein-2 (MIP-2) and monocyte chemoattractant protein-1 (MCP-1) proteins were determined and chemotaxis assays were performed. To evaluate possible cellular signalling pathways phosphorylation of the kinases extracellular-regulated kinase (ERK) and Akt was assessed. In the early phase of sevoflurane post-conditioning expression of TNF-alpha, CINC-1, MIP-2 and MCP-1 was attenuated, leading to a diminished chemotaxis reaction for neutrophils. Phosphorylation of ERK seems to be a possible cellular mechanism in the sevoflurane-induced protection in vitro. Pharmacological post-conditioning of alveolar macrophages with sevoflurane immunmodulates the inflammatory response upon stimulation with endotoxin. This might be a possible option for a therapeutical approach in ALI.

Postconditioning with a volatile anaesthetic in alveolar epithelial cells in vitro

Acute lung injury is a common complication in critically ill patients. The present study examined possible immunomodulating effects of the volatile anaesthetic sevoflurane on lipopolysaccharide (LPS)-stimulated alveolar epithelial cells (AEC) in vitro. Sevoflurane was applied after the onset of injury, simulating a "postconditioning" scenario. Rat AEC were stimulated with LPS for 2 h, followed by a 4-h co-exposure to a CO(2)/air mixture with sevoflurane 2.2 volume %; control cells were exposed to the CO(2)/air mixture only. Cytokine-induced neutrophil chemoattractant-1, monocyte chemoattractant protein-1, intercellular adhesion molecule-1, as well as the potential protective mediators inducible nitric oxide synthase (iNOS)2 and heat shock protein (HSP)-32, were analysed. Additionally, functional assays (chemotaxis, adherence and cytotoxicity assay) were performed. A significant reduction of inflammatory mediators in LPS-stimulated, sevoflurane-exposed AEC was found, leading to reduced chemotaxis, neutrophil adherence and neutrophil-induced AEC killing. While iNOS2 was increased in the sevoflurane group, blocking experiments with iNOS2 inhibitor did not affect sevoflurane-induced decrease of inflammatory mediators and AEC killing. Interestingly, sevoflurane treatment also resulted in an enhanced expression of HSP-32. The data presented in the current study provide strong evidence that anaesthetic postconditioning with sevoflurane mediates cytoprotection in the respiratory compartment in an in vitro model of acute lung injury.

Hypoxia attenuates effector-target cell interaction in the airway and pulmonary vascular compartment

Leucocyte infiltration is known to play an important role in hypoxia-induced tissue damage. However, little information is available about hypoxia and interaction of effector (neutrophils) with target cells (alveolar epithelial cells, AEC; rat pulmonary artery endothelial cells, RPAEC). The goal of this study was to elucidate hypoxia-induced changes of effector-target cell interaction. AEC and RPAEC were exposed to 5% oxygen for 2-6 h. Intercellular adhesion molecule-1 (ICAM-1) expression was determined and cell adherence as well as cytotoxicity assays were performed. Nitric oxide and heat shock protein 70 (HSP70) production was assessed in target cells. Under hypoxic conditions enhanced ICAM-1 production was found in both cell types. This resulted in an increase of adherent neutrophils to AEC and RPAEC. The death rate of hypoxia-exposed target cells decreased significantly in comparison to control cells. Nitric oxide (NO) concentration was enhanced, as was production of HSP70 in AEC. Blocking NO production in target cells resulted in increased cytotoxicity in AEC and RPAEC. This study shows for the first time that target cells are more resistant to effector cells under hypoxia, suggesting hypoxia-induced cell protection. An underlying mechanism for this phenomenon might be the protective effect of increased levels of NO in target cells.

Bidirectional fusion of the heart-forming fields in the developing chick embryo

It is generally thought that the early pre-tubular chick heart is formed by fusion of the anterior or cephalic limits of the paired cardiogenic fields. However, this study shows that the heart fields initially fuse at their midpoint to form a transitory "butterfly"-shaped, cardiogenic structure. Fusion then progresses bi-directionally along the longitudinal axis in both cranial and caudal directions. Using in vivo labeling, we demonstrate that cells along the ventral fusion line are highly motile, crossing future primitive segments. We found that mesoderm cells migrated cephalically from the unfused tips of the anterior/cephalic wings into the head mesenchyme in the region that has been called the secondary heart field. Perturbing the anterior/cranial fusion results in formation of a bi-conal heart. A theoretical role of the ventral fusion line acting as a "heart organizer" and its role in cardia bifida is discussed.

Regression of papilloma high-grade lesions (CIN 2 and CIN 3) is stimulated by therapeutic vaccination with MVA E2 recombinant vaccine

Human papillomavirus (HPV) is the etiologic agent for cervical cancer. In Mexico, a women dies every 2 h, and since 1990 the statistics have shown that the numbers of deaths are increasing. We conducted a phase II clinical trial to evaluate the potential use of the MVA E2 recombinant vaccinia virus in treating high-grade lesions (CIN 2 and CIN 3) associated with oncogenic papillomavirus. Fifty-four female patients with high degree lesions were treated either with an MVA E2 therapeutic vaccine or with conization. Thirty-four women received the therapeutic vaccine, at a total of 10(7) virus particles per dose injected directly into the uterus once every week over a 6-week period. Twenty control patients were treated with conization. By colposcopy, 19 patients out of 34 showed no lesion, in three patients the lesions were reduced by 85-90%, in eight other lesions had reduced by 60%, and in four more patients, they were reduced by 25%. Histological analysis showed total elimination of high-grade lesions in 20 out of 34 patients after treatment with MVA E2. Eleven patients had a 50% reduction in lesion size. In two other patients, the lesion was reduced to CIN 2 and in one more patient the lesion was reduced to low grade (CIN 1). All patients developed antibodies against the MVA E2 vaccine, and generated a specific cytotoxic response against papilloma-transformed cells. DNA viral load was significantly reduced in MVA E2-treated patients. Conization eliminated the lesions in 80% of the patients, but patients did not develop cytotoxic activity specific against cancer cells and did not eliminate the papillomavirus. In addition, three patients treated with conization had recurrence of lesions 1 year later. These results show that therapeutic vaccination with MVA E2 proved to be very effective in stimulating the immune system against papillomavirus, and in generating regression of high-grade lesion.

Hypoxia aggravates lipopolysaccharide-induced lung injury

The animal model of inflammatory response induced by intratracheal application of lipopolysaccharide includes many typical features of acute lung injury or the acute respiratory distress syndrome. A number of experimental investigations have been performed to characterize the nature of this injury more effectively. In inflammatory conditions, hypoxia occurs frequently before and in parallel with pulmonary and non-pulmonary pathological events. This current study was designed to examine the in vivo effect of hypoxia as a potentially aggravating condition in endotoxin-induced lung injury. Lipopolysaccharide, 150 microg, was instilled intratracheally into rat lungs, and thereafter animals were exposed to either normoxia or hypoxia (10% oxygen). Lungs were collected 2, 4, 6 and 8 h later. Inflammatory response and tissue damage were evaluated by quantitative analysis of inflammatory cells and mediators, surfactant protein and vascular permeability. A significantly enhanced neutrophil recruitment was seen in lipopolysaccharide-animals exposed to hypoxia compared to lipopolysaccharide-animals under normoxia. This increased neutrophil accumulation was triggered by inflammatory mediators such as tumour necrosis factor-alpha and macrophage inflammatory protein-1beta, secreted by alveolar macrophages. Determination of vascular permeability and surfactant protein-B showed enhanced concentrations in lipopolysaccharide-lungs exposed to hypoxia, which was absent in animals previously alveolar macrophage-depleted. This study demonstrates that hypoxia aggravates lipopolysaccharide injury and therefore represents a second hit injury. The additional hypoxia-induced inflammatory reaction seems to be predominantly localized in the respiratory compartment, underlining the compartmentalized nature of the inflammatory response.

Nutritional support and quality of life in stable chronic obstructive pulmonary disease (COPD) patients

RATIONALE

Nutritional depletion is a common problem in chronic obstructive pulmonary disease (COPD) patients. It is caused, to a large extent, by an imbalance between low-energy intake and high-energy requirements. This problem adversely affects morbidity and mortality. However, the use of nutritional supplements to reach their energy necessities requires optimisation between positive and adverse effects on outcome before being used systematically as part of their comprehensive care.

PURPOSE

The aim of our study was to investigate the effects of oral nutritional repletion on quality of life in stable COPD patients.

METHODS

Prospective, randomised and multi-centre study. Stable COPD patients with a body mass index 22, a fat-free mass index 16, and/or a recent involuntary weight loss (5% during last month, or 10% during the last 3 months) were studied. Exclusion criteria were to present signs of an airway infection, to have a cardiovascular, neurological, or endocrine disease, to be treated with oral steroids, immunosuppressors or oxygen therapy at home, and to receive nutritional supplements. During 12 weeks, patients were encouraged to ingest a total daily defined energy intake. Randomly, in patients from group A the total daily energy load was Resting Energy Expenditure (REE)x1.7, and those from group B, REE x1.3. Total daily energy intake was achieved with regular food plus, if necessary, oral nutritional supplement rich in proteins (with 50% of whey protein), with predominance of carbohydrates over fat, and enriched in antioxidants. Primary end-point variable was quality of life. Secondary end-point outcomes included body weight, body composition, lung function, handgrip strength, and compliance with the energy intake previously planned. Data were treated with a SAS System. Student's test, Wilcoxon's rank sum test, and Mann-Whitney's test were used.

RESULTS

At baseline both groups of patients were comparable. All patients needed oral nutritional supplements to achieve total daily defined energy intake. After 12 weeks of follow-up, patients in both groups significantly increased energy intake. Patients in group A increased body weight (P=0.001), triceps skin fold thickness (P=0.009) and body fat mass (P=0.02), and decreased body fat-free mass index (P=0.02). In this group a marked increase in airflow limitation was observed. A tendency to increase body weight and handgrip strength, and to decrease airflow limitation was observed in patients from group B. Furthermore, patients in the later group showed a significant improvement in the feeling of control over the disease (P=0.007) and a tendency to better the other criteria in a quality of life scale.

CONCLUSIONS

According to our results, total daily energy intake of REE x 1.3 is preferable to REE x 1.7 in mild stable COPD patients. The administration of oral nutritional supplements, rich in proteins (with 50% of whey protein), with predominance of carbohydrates over fat, and enriched in antioxidants, to achieve total daily defined energy intake in patients in group B was followed by a significant improvement of one criteria (mastery) among many others in a quality of life scale.

[Estimation of bone mass of hemodialysis patients by digital radiologic radiogrammetry (DXR)]

Bone mass (BMD) may be evaluated by digital X-ray radiogrammetry (DXR) which it is estimated from multiple cortical measures carried out on five regions of interest over a simple hand-forearm X-ray film. We included 168 HD patients (108 men and 60 women; 63 +/- 14 and 66 +/- 12 years old respectively--p < 0.05-) coming from seven HD units in Asturias. We performed a hand-forearm X-ray, an epidemiologic questionnaire and we revised their medical and analytical records. As the normative data we used the measurements of a random sample of 247 subjects from our own population. The prevalence of osteoporosis was 7% and 40% in men and women respectively. BMD was correlated with weight (r = 0.346), time on HD (r = -0.188), time on treatment (r = -0.235). The porosity was correlated with PTH levels.

[Clinico-epidemiologic study of urolithiasis in a Caribbean urban area]

Urolithiasis is a common clinical disorder. Its frequency has risen with the development of humanity and varies wirl the country, geographic area, etc. It poses health problems in most countries. The urolithiasis has some potential risk factors such as intrinsic and extrinsic epidemiological, metabolic, physic-chemistry of the urine, mechanics and urinary infection. Our objective in this epidemiological study in a general population was to know the frequency, the potential risk factors, the morbidity, and social and economical impact of the urolithiasis in our subtropical Caribbean country. The prevalence was 4.64% and the annual incidence was 0.1%. Both are with in the estimated range of urolithiasis frequency in the world. It mainly started between 20 and 29 years in both genders. The white (5.2%) and the male (6.36%) patients were the most affected. 40% of all patients had a family history of urolithiasis. It was highly associated with diabetes mellitus, ischaemic cardiopathy, urinary tract infection and arterial hypertension. Stone formation was related to the warmer season. High calcium, protein-purine, carbohydrates and oxalic acid intake together with low fluid intake were closely associated with this disorder. 85% of patients had suffered renal colic and 75% of them more than once. Stone recurrence affected 33.8% of patients and 54.5% of them had more than one recurrence. Procedures for stone removal were needed in 33.8% of subjects. 40% of all patients were admitted to hospital due to urolithiasis morbidity. Non-specific medical treatment had been taken by 49.2% of the patients and specific treatment by none. Urolithiasis in this population was the some as has been reported in others studies. It has shown high frequency, increasing incidence, the same risks factors, high morbidity, and high social and economical impact. The low cost treatment is only taken by half of the patients.

Observer-blinded comparison of two nonopioid analgesics for postoperative pain in piglets

Piglets are popular for studies of respiratory and cardiovascular function, but opioid analgesics are contraindicated in these studies because of central nervous system depression. We evaluated two nonopioid analgesics for postoperative pain relief following implantation of a central arterial catheter via an inguinal incision. Animals were randomly assigned to paracetamol-treated (n=8, rectal suppositories, 100 mg/kg) meloxicam-treated (n=8, 1 mg/kg meloxicam via the catheter) or untreated control group (n=8, placebo suppositories and normal saline). Additional controls received paracetamol or meloxicam, without pain (n=6 for both groups). Behavioral and physiological assessments, and blood sampling were undertaken at nine timed intervals until 24 h after surgery. Multifactorial numerical rating scale (NRS), behavioral and physiological pain scores (PPS) decreased over time for all groups (P<.001). On NRS and behavioral criteria, meloxicam was significantly better than paracetamol (P<.001), and both were better than control (p<.001 for each). Physiological parameters discriminated between the control and analgesia-treated groups, but not between paracetamol and meloxicam. Preliminary pharmacokinetics, determined by isocratic high-performance liquid chromatography (HPLC), revealed no difference in the half-life of paracetamol (2.5+/-0.3 h) vs. meloxicam (3.4+/-0.4 h). Paracetamol and meloxicam provided effective postoperative analgesia in piglets, with meloxicam superior to paracetamol on behavioral criteria.

Epidemiology of acute hepatitis in the Stann Creek District of Belize, Central America

Hepatitis is common in the Stann Creek District of southern Belize. To determine the etiologies, incidence, and potential risk factors for acute jaundice, we conducted active surveillance for cases. Cases of jaundice diagnosed by a physician within the previous 6 weeks were enrolled. Evaluation included a questionnaire and laboratory tests for hepatitis A, B, C, D, and E, a blood film for malaria, and a serologic test for syphilis. Etiologies of jaundice among 62 evaluable patients included acute hepatitis A, 6 (9.7%), acute hepatitis B, 49 (79.0%), hepatitis non-A-E, 2 (3.2%), and malaria, 5 (8.1%). There were no cases of acute hepatitis E. One patient each with antibody to hepatitis C and D were detected. The annualized incidence of hepatitis A was 0.26 per 1,000. All cases of hepatitis A were in children 4-16 years of age. The annualized incidence of hepatitis B, 2.17 per 1,000, was highest in adults aged 15-44 years (4.4 per 1,000) and was higher in men (36 cases; 3.09 per 1,000) than women (13 cases; 1.19 per 1,000). Four (31%) of the women with hepatitis B were pregnant. The annualized incidence was significantly higher in Mestizo (6.18 per 1000) and Maya (6.79 per 1,000) than Garifuna (0.38 per 1,000) or Creole (0.36 per 1,000). Persons with hepatitis B were significantly more likely to be born outside of Belize (82%), had been in Belize < 5 years (73%), and lived and worked in rural areas (96%) than was the general population. Of those > or = 14 years of age with hepatitis B, only 36% were married. Few persons admitted to transfusions, tattoos, IV drug use, multiple sexual partners, visiting prostitutes, or sexually transmitted diseases. Only 1 of 49 had a reactive test for syphilis. Six patients were hospitalized (including 3 with acute hepatitis B and one with hepatitis A), and none to our knowledge died. Acute hepatitis B is the most common cause of viral hepatitis in the Stann Creek District, but the modes of transmission remain obscure. Infants, women attending prenatal clinics, and new workers are potential targets for immunization with hepatitis B vaccine.

[Physical and chemical characterization of industrial nixtamalized corn flour for human consumption in Central America]

The objective of this study was the characterization of industrial nixtamalized maize flour for human consumption and which are marketed in Central America for some selected physical and chemical properties which may contribute to food composition information and help nutrition and micronutrient fortification programs. A total of 12 brands purchased in triplicate were obtained from supermarkets in Guatemala, El Salvador and Honduras. These samples were kept under refrigeration until analyzed. The physical parameters measured and results were the following: particle size with most samples having a high percentage of particles greater than 60 mesh, pH (5.4-7.5), water absorption index (WAI) (3.4-4.0 g gel/g sample), water soluble index (WSI) (4.8-7.8 g/100 g) and flour density (0.410-0.547 g/ml). The differences were statistically significant for all parameters measured, except for WAI. The chemical characteristics included, moisture, protein, fat, ash and dietetic fiber. Differences between flour samples were statistically significant except for fat content. Protein content was low, ranging between 6.7-8.1 g/100 g and total dietary fiber varied between 7.7-12.0 g/100 g. The samples were analyzed for phytic acid with a variation from 632 to 903 mg/100 g, with statistical significant differences. The samples were also analyzed for total and soluble (pH 7.5) iron, phosphorus, calcium, potassium, zinc, copper, manganese, and magnesium. The difference in the iron and calcium content between flour samples were statistically significant. The physical and chemical variability found between flour samples of nixtamalized maize was relatively high and it is recommended to establish quality standards through raw material and process standardization for greater effectiveness of nutrition programs and activities on micronutrient fortification which may be pursued in the future.

Genital mycoplasmosis in rats: a model for intrauterine infection

PROBLEM

Microbial infections of the chorioamnion and amniotic fluid have devastating effects on pregnancy outcome and neonatal morbidity and mortality. The mechanisms by which bacterial pathogens cause adverse effects are best addressed by an animal model of the disease with a naturally-occurring pathogen.

METHOD OF STUDY

Intrauterine infection in humans as well as genital mycoplasmosis in humans and rodents is reviewed. We describe a genital infection in rats, which provides a model for the role of infection in pregnancy, pregnancy wastage, low birth weight, and fetal infection.

RESULTS

Infection of Sprague-Dawley rats with Mycoplasma pulmonis either vaginally or intravenously resulted in decreased litter size, increased adverse pregnancy outcome, and in utero transmission of the microorganism to the fetus.

CONCLUSION

Mycoplasma pulmonis is an ideal model to study maternal genital infection during pregnancy, the impact of infections on pregnancy outcome, fetal infection, and maternal-fetal immune interactions.

Vaxfectin enhances antigen specific antibody titers and maintains Th1 type immune responses to plasmid DNA immunization

Antigen specific immune responses were characterized after intramuscular immunization of BALB/c mice with 5 antigen encoding plasmid DNAs (pDNAs) complexed with Vaxfectin, a cationic lipid formulation. Vaxfectin increased IgG titers for all of the antigens with no effect on the CTL responses to the 2 antigens for which CTL assays were performed. Both antigen specific IgG1 and IgG2a were increased, although IgG2a remained greater than IgG1. Furthermore, Vaxfectin had no effect on IFN-gamma or IL-4 production by splenocytes re-stimulated with antigen, suggesting that the Th1 type responses typical of intramuscular pDNA immunization were not altered. Studies with IL-6 -/- mice suggest that the antibody enhancement is IL-6 dependent and results in a correlative increase in antigen specific antibody secreting cells.

Mycoplasma pulmonis genital disease: effect of rat strain on pregnancy outcome

BACKGROUND AND PURPOSE

Mycoplasma pulmonis is a natural pathogen of the respiratory and genital tracts of rats. Differential susceptibility and severity of the respiratory form of the disease, known as murine respiratory mycoplasmosis (MRM), exist between rat strains. We now report that specific rat strains vary in susceptibility to genital tract infection and pregnancy outcome.

METHODS

Specific-pathogen-free (SPF) female F344, LEW, Wistar (WIS) and Sprague Dawley (SD) rats were intravaginally inoculated with 3 x 10(7) colony-forming units (CFU) of M. pulmonis strain X1048 or sterile diluent, and allowed to breed at 10 days after inoculation. Pregnant dams and pups were necropsied within 24 hours of parturition. At necropsy, culture for M. pulmonis was performed on dam and pups, and adverse effects on pregnancy outcome were assessed by determination of the incidence of infertility, fetal resorption, stillbirths, changes in litter size, and pup birth weight. Blood from dams was collected prior to inoculation and at time of necropsy for measurement of IgM and IgG antibodies to M. pulmonis.

RESULTS

At time of necropsy, WIS (50%) and SD (60%) dams had a higher frequency of M. pulmonis culture positivity in the genital tract than did LEW (22.2%) and F344 (17.6%) dams. Dams that were still infected with M. pulmonis at time of necropsy had various complications. The SD rats had the greatest degree of adverse effects on pregnancy outcome, which were: infertility, decreased litter size (P < or = 0.01), decreased pup birth weight (P < or = 0.01), increased frequency of resorptions, stillbirths (P < or = 0.05), and the highest rate of pup pulmonary infection (23.1%) (P < or = 0.001). Despite a 50% colonization rate, WIS dams were the least adversely affected. The WIS pups born from M. pulmonis. infected dams had slight decrease in birth weight, and only 6% had pulmonary infections. The LEW infected dams developed infertility and lower numbers of liveborn pups without evidence of vertical transmission. The F344 infected dams had lower numbers of liveborn pups that were smaller than their control counterparts, and none had pulmonary infections. None of the animals had detectable IgM and IgG antibodies to M. pulmonis before inoculation. At time of necropsy, all animals inoculated with M. pulmonis developed significantly (P < or = 0.001) higher amounts of M. pulmonis IgG and IgM antibodies, with SD rats developing the highest amounts (P < or = 0.005).

CONCLUSIONS

Both F344 and LEW rats are more resistant to vaginal inoculation with M. pulmonis than are WIS and SD rats. However, only SD dams suffered severe adverse effects on pregnancy outcome. The SD dams also had the greatest IgM and IgG antibody response to M. pulmonis. Our studies clearly indicate differences among rat strains in their susceptibility to vaginal inoculation with M. pulmonis and in secondary complications associated with infection. This system may be a useful model for determining host-specific factors that influence the outcome of natural mycoplasmal infections of the genital tract.

Relationship between weight at birth and the number and size of renal glomeruli in humans: a histomorphometric study

BACKGROUND

The number of nephrons in humans varies considerably under normal circumstances, and retarded intrauterine growth has been reported to be associated with a significant reduction in nephron number. Low nephron number may be an independent risk factor for the development of hypertension. We therefore decided to evaluate the relationship between body weight at birth and the number and size of nephron units.

METHODS

We examined coronal sections of the kidneys of 35 neonates who died within two weeks of birth because of hyaline membrane, infectious complications, brain hemorrhage, or perinatal hypoxia and had no urinary congenital malformations. Nine of them (5 males and 4 females) were between 36 and 37 weeks of gestation, and the rest had 38 or more weeks of gestation. Eighteen neonates weighed less than 2500 g at birth [low birth weight (LBW); 9 females and 9 males], and 17 had weights above this value [normal birth weight (NBW); 8 females and 9 males]. In each section, glomeruli present in four sequential subcapsular microscopic fields, corresponding to 0.6 mm2, were counted; in addition, the area of each of 65 consecutive glomeruli was determined by a computerized measurement system. Glomerular volume was calculated from the glomerular area. Linear regression analysis was used to test the relationship between glomerular number and size and the weight at birth.

RESULTS

The number of glomeruli per 0.6 mm2 of renal cortex was 92.9 +/- 4.85 in the LBW and 105.8 +/- 3.91 in NBW (P < 0.0001). Glomerular volume (micro(3) x 10(-3)) was 529.1 +/- 187.63 in the LBW group and 158.0 +/- 49.89 in the NBW group (P < 0.0001). The glomeruli occupied 8.59 +/- 1.38% of the kidney area under examination in the LBW group and 14.3 +/- 2.75% in the NBW group (P < 0.0001). There were significant direct correlations between the weight at birth and the number of glomeruli (r = 0.870, P < 0.0001) and area occupied by glomeruli (r = 0.935, P < 0.0001). There were inverse correlations between the number of glomeruli and the volume of the glomeruli (r = -0.816, P < 0.0001) and the weight at birth and glomerular volume (r = -0.848, P < 0.0001). These findings were independent of sex and race (black vs. white). Essential arterial hypertension existed in 38.9% of the mothers of children with LBW and in 5.9% of the mothers of children with NBW (P < 0.05). Smoking habits existed in 50% of the mothers of LBW children and in 11.8% of the mothers of NBW children (P < 0.05).

CONCLUSION

There are strong correlations between glomerular number (direct) and size (inverse) with LBW in this cohort. Endowment with decreased nephron numbers may be a risk factor for hypertension and the rate of progression of renal disease.

[Langerhans cell histiocytosis. Clinical longitudinal study of 21 patients]

BACKGROUND

Clinical data of patients with Langerhans cell histiocytosis are well established, although new diagnostic methods and specially long term evolution of the disease with lung involvement are not well-known.

METHODS

In all cases, patients were diagnosed by means of pathologic study of the lung samples, either by transbronchial biopsy in 7 patients, or by surgical lung biopsy in 8 patients. Six patients were diagnosed by bone biopsy. Other patients were diagnosed by bronchoalveolar lavage (BAL). In 4 patients, who underwent BAL, the study of antibodies CD1 (CD1a) was positive (> 5%). Lymphocytopenia was detected in 28% of patients, whereas no decrease in delayed cutaneous hypersensitivity tests was detected in any of them. After a follow-up study of 12.8 years (range: 4-22 years), 7 patients had dead, 6 patients showed severe lung involvement and other 5 patients did not have lung affection.

CONCLUSIONS

The diagnosis of Langerhans cell histiocytosis has improved by detection of immunologic and histochemical markers recently introduced. The study of the delayed cutaneous hypersensitivity tests did not show anergy or hipoergy. Long term evolution of patients with lung involvement is poor.

High-dose folic acid supplementation in rats: effects on gestation and the methionine cycle

There is new evidence that a good folate status may play a critical role in the prevention of neural-tube defects and in lowering elevated homocysteine concentrations. This adequate folate status may be achieved through folic acid dietary supplementation. Folate is a water-soluble vitamin with a low potential toxicity. However, the possible consequences of long-term high-dose folic acid supplementation are unknown, especially those related to the methionine cycle, where folate participates as a substrate. With the aim of evaluating such possible effects, four groups of Wistar rats were classified on the basis of physiological status (virgin v. pregnant) and the experimental diet administered (folic-acid-supplemented, 40 mg/kg diet v. control, 2 mg folic acid/kg diet). Animals were fed on the diets for 3 weeks. Results showed that gestation outcome was adequate in both groups regardless of the dietary supplementation. However, there were reductions (P < 0.001) in body weight and vertex-coccyx length in fetuses from supplemented dams v. control animals. Folic acid administration also induced a higher (P < 0.01) S-adenosylmethionine: S-adenosylhomocysteine value due to increased S-adenosylmethionine synthesis (P < 0.01). However, hepatic DNA methylation and serum methionine concentrations remained unchanged. Serum homocysteine levels were reduced in supplemented dams (P < 0.05). Finally, pregnancy caused lower serum folate, vitamin B6 and vitamin B12 levels (P < 0.05). Folic acid administration prevented the effect of pregnancy and raised folate levels in dams, but did not change levels of vitamins B12 and B6. These new findings are discussed on the basis of potential benefits and risks of dietary folic acid supplementation.

Effects of Mycoplasma fermentans incognitus on differentiation of THP-1 cells

Mycoplasma fermentans incognitus has been isolated from human tissue in patients both with and without AIDS who died of systemic infection. M. fermentans incognitus and other strains of M. fermentans have been associated with rheumatoid arthritis. While cell extracts of M. fermentans incognitus can induce changes in murine and human cells of the monocytic lineage, little is known about interactions of viable organisms with such cells. Because of the central role of macrophages in chronic inflammation, we examined the effects of M. fermentans incognitus on surface markers and functions of THP-1 cells, a well-characterized human monocytic cell line. This cell line has been used extensively in studies of macrophage differentiation, especially following exposure to phorbol esters. Changes in cell morphology, phagocytosis, rate of cell division, and selected surface markers were evaluated in cultures of THP-1 cells exposed to phorbol myristate acetate (PMA), M. fermentans incognitus, or both. As reported by other investigators, PMA induced THP-1 cells to differentiate into cells resembling tissue macrophages. M. fermentans incognitus only minimally affected changes induced by PMA, slightly increasing the percentage of cells positive for FCgammaRI and major histocompatibility complex (MHC) class II antigens. M. fermentans incognitus alone induced an incomplete arrest in the cell cycle at G0 phase, increased phagocytic ability, and enhanced expression of FCgammaRI, CR3, CR4, and MHC class II antigens.

High dietary folate supplementation affects gestational development and dietary protein utilization in rats

There is new evidence that good folate status may play a critical role in the prevention of neural tube defects and in the maintenance of adequate homocysteine levels, an amino acid recently identified as a risk factor for cardiovascular disease. This has led to different folate recommendations, all of them much higher than the present dietary recommendations. Folic acid is a water-soluble vitamin with a low potential toxicity. However, the possible consequences of long-term, high folate intakes are unknown. Therefore, the present study was undertaken to determine the effects of long-term, high dietary folate supplementation on gestational and nutritional markers in pregnant and virgin rats. Four groups of Wistar rats were classified on the basis of physiological status (virgin or pregnant) and the experimental diets administered (folic acid supplemented, 40 mg/kg diet; or control diet, 2 mg folic acid/kg diet). Rats were fed their respective diets for 3 wk. Two critical periods were used for metabolic balance studies (experimental d 1-5 and 17-21), which involved the determination of fat and protein digestibilities as well as metabolic protein utilization (MPU) and net protein utilization (NPU). Gestational development (number of live fetuses) was adequate in both diet groups regardless of folate supplementation. However, body weight and vertex-coccyx length in fetuses from supplemented dams were less than (P < 0.0001) in fetuses of control dams. Fat and nitrogen digestibilities were not affected by supplementation, but MPU and NPU coefficients were significantly lower (P < 0.05) in the folic acid-supplemented groups, irrespective of physiological status, compared to control rats. These new findings of macro-micronutrient interactions caused by high folate supplementation are discussed on the basis that the vitamin may act as a xenobiotic more than as a nutrient.

Normal appearances of technetium-99m dimercaptosuccinic acid in children on planar imaging

Thirty-two children who underwent renal arteriography with normal results also underwent technetium-99m dimercaptosuccinic acid (DMSA) imaging. Variations in the normal appearance of 99mTc-DMSA images are described in these children. Criteria for high-quality 99mTc DMSA images are defined in terms of kidney outline and contrast between the inner and the outer part of the kidney. Most of the images in this study were of high quality. The two most common features of normal 99mTc-DMSA images were a round-shaped (50%) or flat (either lateral or medial aspect) (24.8%) contour. A small number of unusual appearances were observed and these have been illustrated. The mean differential function of the left kidney was 51% with a range of 45%-57%.