Prolonged recruitment manoeuvre improves lung function with less ultrastructural damage in experimental mild acute lung injury

The effects of prolonged recruitment manoeuvre (PRM) were compared with sustained inflation (SI) in paraquat-induced mild acute lung injury (ALI) in rats. Twenty-four hours after ALI induction, rats were anesthetized and mechanically ventilated with VT = 6 ml/kg and positive end-expiratory pressure (PEEP) = 5 cmH(2)O for 1 h. SI was performed with an instantaneous pressure increase of 40 cmH(2)O that was sustained for 40 s, while PRM was done by a step-wise increase in positive inspiratory pressure (PIP) of 15-20-25 cmH(2)O above a PEEP of 15 cm H(2)O (maximal PIP = 40 cmH(2)O), with interposed periods of PIP = 10 cmH(2)O above a PEEP = 15 cmH(2)O. Lung static elastance and the amount of alveolar collapse were more reduced with PRM than SI, yielding improved oxygenation. Additionally, tumour necrosis factor-alpha, interleukin-6, interferon-gamma, and type III procollagen mRNA expressions in lung tissue and lung epithelial cell apoptosis decreased more in PRM. In conclusion, PRM improved lung function, with less damage to alveolar epithelium, resulting in reduced pulmonary injury. (C) 2009 Elsevier BLV. All rights reserved.

Management of Neuroendocrine Tumors: A Meeting of Experts from Latin America

A panel of experts from Latin America convened in Brazil, in May of 2007, for consensus recommendations regarding the management of neuroendocrine tumors ( NETs) of the gastrointestinal tract and pancreas. The recently introduced World Health Organization classification of NETs represents a step forward, but the former classification of carcinoids into foregut, midgut and hindgut is still likely to be useful in the near future. Macroscopic description of the tumor should be followed by light microscopic examination and immunohistochemical staining, whereas other techniques might not be widely available in Latin America. Surgery remains the mainstay of treatment for patients with potentially curable tumors, and adequate selection is paramount in order to optimize treatment results. Regarding systemic therapy, patients with well-differentiated tumors or islet-cell carcinomas may be categorized as having indolent disease, while patients with poorly differentiated, anaplastic, and small-cell carcinomas, or with atypical carcinoids, may be approached initially as having aggressive disease. Somatostatin analogues play a cytostatic role in indolent tumors, and chemotherapy may play a role against other, more aggressive NETs. Obviously, there is an urgent need for novel therapies that are effective against NETs. Copyright (C) 2008 S. Karger AG, Basel

Immunohistochemical analysis of p53, APE1, hMSH2 and ERCC1 proteins in actinic cheilitis and lip squamous cell carcinoma

Aims: This study has compared the tissue expression of the p53 tumour suppressor protein and DNA repair proteins APE1, hMSH2 and ERCC1 in normal, dysplastic and malignant lip epithelium. Methods and results: Morphological analysis and immunohistochemistry were performed on archived specimens of normal lip mucosa (n = 15), actinic cheilitis (AC) (n = 30), and lip squamous cell carcinoma (LSCC) (n = 27). AC samples were classified morphologically according to the severity of epithelial dysplasia and risk of malignant transformation. LSCC samples were morphologically staged according to WHO and invasive front grading (IFG) criteria. Differences between groups and morphological stages were determined by bivariate statistical analysis. Progressive increases in the percentage of epithelial cells expressing p53 and APE1 were associated with increases in morphological malignancy from normal lip mucosa to LSCC. There was also a significant reduction in epithelial cells expressing hMSH2 and ERCC1 proteins in the AC and LSCC groups. A higher percentage of malignant cells expressing APE1 was found in samples with an aggressive morphological IFG grade. Conclusions: Our data showed that epithelial cells from premalignant to malignant lip disease exhibited changes in the expression of p53, APE1, hMSH2 and ERCC1 proteins; these molecular change might contribute to lip carcinogenesis.

Small airway remodeling in acute respiratory distress syndrome: a study in autopsy lung tissue

Introduction: Airway dysfunction in patients with the Acute Respiratory Distress Syndrome (ARDS) is evidenced by expiratory flow limitation and dynamic hyperinflation. These functional alterations have been attributed to closure/obstruction of small airways. Airway morphological changes have been reported in experimental models of acute lung injury, characterized by epithelial necrosis and denudation in distal airways. To date, however, no study has focused on the morphological airway changes in lungs from human subjects with ARDS. The aim of this study is to evaluate structural and inflammatory changes in distal airways in ARDS patients. Methods: We retrospectively studied autopsy lung tissue from subjects who died with ARDS and from control subjects who died of non pulmonary causes. Using image analysis, we quantified the extension of epithelial changes (normal, abnormal and denudated epithelium expressed as percentages of the total epithelium length), bronchiolar inflammation, airway wall thickness, and extracellular matrix (ECM) protein content in distal airways. The Student`s t test or the Mann-Whitney test was used to compare data between the ARDS and control groups. Bonferroni adjustments were used for multiple tests. The association between morphological and clinical data was analyzed by Pearson rank test. Results: Thirty-one ARDS patients (A: PaO(2)/FiO(2) <= 200, 45 +/- 14 years, 16 males) and 11 controls (C:52 +/- 16 years, 7 males) were included in the study. ARDS airways showed a shorter extension of normal epithelium (A:32.9 +/- 27.2%, C:76.7 +/- 32.7%, P < 0.001), a larger extension of epithelium denudation (A:52.6 +/- 35.2%, C:21.8 +/- 32.1%, P < 0.01), increased airway inflammation (A:1(3), C:0(1), P = 0.03), higher airway wall thickness (A:138.7 +/- 54.3 mu m, C:86.4 +/- 33.3 mu m, P < 0.01), and higher airway content of collagen I, fibronectin, versican and matrix metalloproteinase-9 (MMP-9) compared to controls (P = 0.03). The extension of normal epithelium showed a positive correlation with PaO(2)/FiO(2) (r(2) = 0.34; P = 0.02) and a negative correlation with plateau pressure (r(2) = 0.27; P = 0.04). The extension of denuded epithelium showed a negative correlation with PaO(2)/FiO(2) (r(2) = 0.27; P = 0.04). Conclusions: Structural changes in small airways of patients with ARDS were characterized by epithelial denudation, inflammation and airway wall thickening with ECM remodeling. These changes are likely to contribute to functional airway changes in patients with ARDS.

In situ hybridization detection of homeobox genes reveals distinct expression patterns in oral squamous cell carcinomas

Aims: To analyse the expression of three homeobox genes (HOXA7, PITX1 and PRRX1) in oral squanous cell carcinomas (OSCC) and the relationship of such expression to certain distinct histopathological features of OSCC and in comparison to adjacent non-neoplastic epithelium (NT). Methods and results: Digoxigenin-labelled riboprobes that are specific for each homeobox gene were generated and in situ hybridization was carried out on frozen sections. In NT samples, HOXA7 and PITX1 transcripts were found more frequently in all epithelial layers, while PRRX1 was expressed in the basal layer. With OSCC samples, expression of the three genes was associated with all histological features. However, the HOXA7 and PITX1 signals were more intense in sheets and nests and PRRX1 in small nests and isolated cells. Conclusion: HOXA7, PIXT1 and PRRX1 homeobox genes have different patterns of expression in OSCC depending on its histological features.

Urinary glycosaminoglycans as biomarker for urothelial injury: Is it possible to discriminate damage from recovery?

OBJECTIVES The glycosaminoglycan (GAG) layer is referred to as a bladder protective factor. We reproduced an experimental model of urothelial damage to assess GAG metabolism in the process of injury and recovery of the urothelium. METHODS Wistar female rats were bladder catheterized and instilled with either protamine sulfate (PS groups) or sterile saline (control groups). At different days after the procedure, 24-hour urine samples were obtained. The urinary levels of hyaluronic acid (HA) and sulfated glycosaminoglycan were determined in all groups and in nonmanipulated rats (day 0). Additionally, sulfated-GAG synthesis was assessed by the incorporation of [S-35]-inorganic sulfate. The bladders were analyzed by histochemical staining for HA and immunofluorescence for heparin sulfate and syndecan-4. RESULTS Urinary HA and sulfated-GAG were elevated after PS injection (P <0.05). A greater concentration of [S-35] -labeled GAG in the PS group animals on the fifth day and, especially, on the seventh day represented increased GAG synthesis at these periods (P <0.05). Bladder sections from the PS group animals on day 1 showed a greater amount of HA in the urothelium. PS instillation damaged the urothelium layer of heparin sulfate and syndecan-4 seen in the control animals. On day 5, patchy areas of a restored layer were seen, and, on day 7, this layer had completely regenerated. CONCLUSIONS Urinary GAG cannot differentiate urothelial damage from recovery. Elevated levels of urinary GAG can result from either desquamation of the surface cell GAG layer or increased GAG synthesis to regenerate the damaged urothelium.

Furosemide impairs nasal mucociliary clearance in humans

Furosemide, a potent diuretic, affects ion and water movement across the respiratory epithelium. However, the effects of furosemide, as clinically used, on mucociliary clearance, a critical respiratory defense mechanism, are still lacking in humans. Fourteen young healthy subjects were assigned to three random interventions, spaced one-week apart: no intervention (control), oral furosemide (40 mg), and furosemide + oral volume replacement (F + R). Nasal mucociliary clearance was assessed by saccharine test (STT), and mucus properties were in vitro evaluated by means of contact angle and transportability by sneeze. Urine output and osmolality were also evaluated. Urine output increased and reduced urine osmolality in furosemide and F + R compared to the control condition. STT remained stable in the control group. In contrast, STT increased significantly (40%) after furosemide and F + R. There were no changes in vitro mucus properties in all groups. In conclusion, furosemide prolongs STT in healthy young subjects. This effect is not prevented by fluid replacement, suggesting a direct effect of furosemide on the respiratory epithelium. (C) 2010 Elsevier B.V. All rights reserved.

Preoperative Gastric Acid Secretion and the Risk to Develop Barrett`s Esophagus After Esophagectomy for Chagasic Achalasia

The aim of this study was to determine the contribution of preoperative gastric secretory and hormonal response, to the appearance of Barrett`s esophagus in the esophageal stump following subtotal esophagectomy. Thirty-eight end-stage chagasic achalasia patients submitted to esophagectomy and cervical gastric pull-up were followed prospectively for a mean of 13.6 +/- 9.2 years. Gastric acid secretion, pepsinogen, and gastrin were measured preoperatively in 14 patients who have developed Barrett`s esophagus (Group I), and the results were compared to 24 patients who did not develop Barrett`s esophagus (Group II). In the group (I), the mean basal and stimulated preoperative gastric acid secretion was significantly higher than in the group II (basal: 1.52 vs. 1.01, p = 0.04; stimulated: 20.83 vs. 12.60, p = 0.01). Basal and stimulated preoperative pepsinogen were also increased at the Group I compared to Group II (Basal = 139.3 vs. 101.7, p = 0.02; stimulated = 186.0 vs. 156.5, p = 0.07. There was no difference in preoperative gastrin between the two groups. Gastritis was present during endoscopy in 57.1% of the Group I, while it was detected in 16.6% of the Group II, p = 0.014. Barrett`s esophagus in the esophageal stump was associated to high preoperative levels of gastric acid secretion, serum pepsinogen, and also gastritis in the transposed stomach.

Barrett`s esophagus (BE) and carcinoma in the esophageal stump (ES) after esophagectomy with gastric pull-up in achalasia patients: A study based on 10 years follow-up

Background: Subtotal esophagectomy and gastric pull-up with cervical anastomosis is the main treatment for advanced achalasia. This surgical technique has been associated to esophagitis and also Barrett`s epithelium following esophagectomy. Aim: To analyze late clinical, endoscopic, and pathologic findings in the esophageal stump (ES) mucosa after subtotal esophagectomy in patients treated for advanced chagasic achalasia. Methods: 101 patients submitted to esophagectomy and cervical gastroplasty were followed-up prospectively for a mean of 10.5 +/- 8.8 years. All patients underwent clinical, endoscopic and histopathological evaluation every 2 years. Gastric acid secretion was also assessed. Results: The incidence of esophagitis in the esophageal stump (45.9% at 1 year; 71.9% at 5 years, and 70.0% at 10 years follow-up); gastritis in the transposed stomach (20.4% at 1 year, 31.0% at 5 years, and 40.0% at 10 or more years follow-up), and the occurrence of ectopic columnar metaplasia and Barrett`s Esophagus in the ES (none until 1 year; 10.9% between 1 and 5 years; 29.5% between 5 and 10 years; and 57.5% at 10 or more years follow-up), all rose over time. Gastric acid secretion returns to its preoperative values 4 years postoperatively. Esophageal stump cancer was detected in the setting of chronic esophagitis in five patients: three squamous cell carcinomas and two adenocarcinomas. Conclusion: (1) Esophagitis and Barrett`s esophagus in the esophageal stump rose over time. (2) These mucosal alterations and the development of squamous cell carcinoma and adenocarcinoma are probably due to exposure to duodenogastric reflux, and progressively higher acid output in the transposed stomach.

Trypan blue staining for capsulorhexis: Ultrastructural effect on lens epithelial cells and capsules

PURPOSE: To evaluate the ultrastructural effect of trypan blue 0.1% staining for capsulorhexis on lens epithelial cells (LECs) and capsules SETTING: Division of Ophthalmology. University of Sao Paulo, Sao Paulo, Brazil METHODS: Before capsulorhexis, patients were randomly assigned to 1 of 2 groups Trypan blue 0 1% staining was performed in the treatment group No trypan blue was used in the control group Samples of capsules with LECs were fixed and analyzed with routine optical microscopy techniques. immunohistochemistry for beclin-1 expression (a marker of autophagy), terminal deoxynucleotidyl transf erase-mediated dUTP-biotin nick-end labeling to detect apoptosis, and transmission electron microscopy (TEM) Morphometric analyses were performed. and the 2 sets of data were compared. RESULTS: Each group comprised 15 patients Cell death by autophagy and apoptosis was observed in the treatment group but not in the control group The TEM images of subcapsular epithelium cells showed mitochondria` rupture, dilation of the cisterns of the endoplasmic reticulum, increased cytoplasmic and nuclear electron density, and abnormalities in the nuclear profile of trypan blue-stained cells. Morphometric analysis showed statistically significant differences between the 2 groups in the longest nuclear axes and the ratio between the total nuclear perimeter and the cell area (P = .03) The difference in capsule thickness between groups was not significant. CONCLUSION: Trypan blue caused LEC death, which supports the hypothesis that staining with trypan blue 0 1% can help reduce the incidence of posterior capsule pacification after cataract surgery

Early keratocyte apoptosis after epithelial scrape injury in the human cornea

Animal studies in mice, rats, rabbits, pigs and hens demonstrated that anterior keratocytes undergo programmed cell death or apoptosis after corneal epithelial injury. Many other wound healing changes subsequently follow the keratocyte apoptosis response. This study evaluated early keratocyte apoptosis after corneal epithelial scrape injury in human eyes scheduled for enucleation for malignancy. Two eyes had corneal epithelial scrape 1 h prior to the enucleation and another eye served as a control and had no corneal scrape prior to enucleation. One additional eye was enucleated, washed with balanced salt solution, and then had the corneal epithelium scraped 1 h prior to processing for analysis. Apoptosis was identified by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay and confirmed by transmission electron microscopy (TEM). Anterior keratocyte apoptosis was detected in the three corneas that had epithelial scrape injury, but not in the control unwounded cornea. This study confirmed that keratocyte apoptosis is also an early response to corneal epithelial injury in humans and showed that tears are not essential for keratocyte apoptosis to occur in response to epithelial injury. (C) 2009 Elsevier Ltd. All rights reserved.

Synergistic effect of ethanol and mitomycin C on corneal stroma

PURPOSE: To investigate the combined effects of ethanol and mitomycin C (MMC) application on the corneal stroma of rabbits that underwent photorefractive keratectomy (PRK). METHODS: Twenty-four rabbits (24 eyes) underwent PRK to correct -9.00 diopters of myopia. Twelve eyes had ethanol application before removing the epithelium and 12 eyes had the epithelium manually removed without ethanol, Eyes in both groups had topical MMC 0.02% application for 12 seconds immediately after excimer laser ablation. Twelve rabbits were sacrificed at two time points-4 hours and 4 weeks after surgery-and immunohistochemistry was performed with TUNEL assay, alpha-smooth muscle actin (alpha-SMA), and DAPI. RESULTS: More TUNEL-positive cells were observed in the ethanol-treated group compared to the mechanical debridement group at 4 hours after surgery (P<.01). No significant difference in alpha-SMA-positive cells was detected, between the two groups at 4 weeks after sugery. However, decreased keratocyte density in the anterior stroma was more pronounced in the ethanol-treated group compared to the mechanical debridement (P<.02). CONCLUSIONS: Ethanol application for epithelial removal during PRK seems to produce a synergistic effect with MMC, resulting in fewer keratocytes in the anterior stroma of rabbit corneas treated with MMC and ethanol than in corneas treated with MMC alone after PRK.

The soybean concentrated extract proliferates the vagina of adult rats

Objective: The aim of this study was to evaluate changes induced on the vagina of ovariectomized rats after treatment with soybean concentrated extract or conjugated equine estrogens and the association of both drugs. Methods: We conducted an experimental study with 50 ovariectomized rats that were randomly divided into five equal groups of 10 animals: GI received vehicle, GII received soybean concentrated extract 46 mg/kg per day, GIII received soybean concentrated extract 120 mg/kg per day, GIV received conjugated equine estrogens 50 mu g/kg per day, and GV received conjugated equine estrogens 50 mu g/kg and soybean concentrated extract 46 mg/kg per day. The substances were administered by gavage during 21 consecutive days. After that, the animals were killed under anesthesia and the vagina was removed for histological and immunohistochemical analysis. Data were initially submitted to analysis of variance. Whenever a significant difference was detected, the study was complemented with the Tukey-Kramer test for multiple comparisons. Results: GII did not show any differences on the vaginal epithelium or collagen compared with GI. GIII presented an increase in vaginal epithelium and collagen amount. GIV had the highest amount of collagen and the signals of vaginal proliferation. GV did not show any additional effect compared with GIV. Conclusions: Our data suggest that a high dose of isoflavone-rich soy extract may have positive effects on the vaginal structures of ovariectomized rats, but this action is less than that of estrogen treatment on vaginal thickness. In addition, soy extract may not block the estrogen effect on vaginal tissue.

Observations on the Female Internal Reproductive Organs of the Brown Howler Monkey (Alouatta guariba clamitans)

Alouatta guariba clamitans (brown howler monkey) is an endemic primate from the southeastern Brazil tropical forests, classified as near threatened by the IUCN Red List 2007. The genus Aloualta is one of the most difficult New World monkeys to breed and rear in captivity. In this study we examined the macroscopic and histological aspects of the female genital tract of wild brown howler monkeys to provide baseline information for future reproduction research. The anatomical relationship between the vagina, uterus, broad ligament, oviducts and ovaries are those of a typical primate reproductive tract. The fundic portion of the uterus is globoid, the cervix is well developed, which confers to the uterus an elongated shape, and the vagina is a long flattened channel. Histological analysis conducted in females in the follicular phase revealed large quantities of interstitial luteinized tissue in the ovaries, a stratified nonkeratinized vaginal epithelium, lack of glands in the vaginal mucosa and simple tubular endometrial glands. The observed anatomical features should be considered in the adaptation and application of assisted reproductive techniques aimed at improving captive reproduction for species conservation. Am. J. Primatol. 71:145-152, 2009. (C) 2008 Wiley-Liss, Inc.