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We describe the geographical variation in tree species composition across Amazonian forests and show how environmental conditions are associated with species turnover. Our analyses are based on 2023 forest inventory plots (1 ha) that provide abundance data for a total of 5188 tree species. Within-plot species composition reflected both local environmental conditions (especially soil nutrients and hydrology) and geographical regions. A broader-scale view of species turnover was obtained by interpolating the relative tree species abundances over Amazonia into 47,441 0.1-degree grid cells. Two main dimensions of spatial change in tree species composition were identified. The first was a gradient between western Amazonia at the Andean forelands (with young geology and relatively nutrient-rich soils) and central-eastern Amazonia associated with the Guiana and Brazilian Shields (with more ancient geology and poor soils). The second gradient was between the wet forests of the northwest and the drier forests in southern Amazonia. Isolines linking cells of similar composition crossed major Amazonian rivers, suggesting that tree species distributions are not limited by rivers. Even though some areas of relatively sharp species turnover were identified, mostly the tree species composition changed gradually over large extents, which does not support delimiting clear discrete biogeographic regions within Amazonia., (© 2024. The Author(s).)

Cricopharyngeal achalasia (CPA), also known as cricopharyngeal bar, is a rare motor disorder affecting the upper oesophageal sphincter. This comprehensive literature review focuses on clinical aspects that can assist physicians in daily decision-making. The diagnosis of CPA is primarily based on symptoms of upper dysphagia and radiological identification of a posterior bar. However, the diagnostic process is not standardized and necessitates a multimodal approach, including radiological, endoscopic, and manometric studies performed by various specialists. Treatment options for CPA include botulinum toxin injection, endoscopic balloon dilatation, open or endoscopic surgery, and cricopharyngeal peroral endoscopic myotomy (CP-POEM). CP-POEM is the latest indication for POEM and has shown promising results with minimal adverse events, though high-quality evidence is still lacking., Competing Interests: Declaration of competing interest Fermin Estremera-Arevalo and Eduardo Albéniz declares no conflicts of interest., (Copyright © 2024. Published by Elsevier Ltd.)

Introduction: The diagnosis of intestinal tuberculosis is challenging even nowadays. This study aims to report the positivity rates of new diagnostic methods such as immunohistochemistry and Real-Time Polymerase Chain Reaction in patients with intestinal tuberculosis, as well as describe the pathological and endoscopic features of intestinal tuberculosis in our population., Methods: This was a retrospective observational study conducted in patients diagnosed with intestinal tuberculosis, between 2010 to 2023 from the Hospital Nacional Daniel Alcides Carrion and a Private Pathology Center, both located in Peru. Clinical data was obtained, histologic features were independently re-evaluated by three pathologists; and immunohistochemistry and real-time Polymerase Chain Reaction evaluation were performed. The 33 patients with intestinal tuberculosis who fulfilled the inclusion criteria were recruited., Results: Immunohistochemistry was positive in 90.9% of cases, while real-time Polymerase Chain Reaction was positive in 38.7%. The ileocecal region was the most affected area (33.3%), and the most frequent endoscopic appearance was an ulcer (63.6%). Most of the granulomas were composed solely of epithelioid histiocytes (75.8%). Crypt architectural disarray was the second most frequent histologic finding (78.8%) after granulomas, but most of them were mild., Conclusion: Since immunohistochemistry does not require an intact cell wall, it demonstrates higher sensitivity compared to Ziehl-Neelsen staining. Therefore, it could be helpful for the diagnosis of paucibacillary tuberculosis., (© 2024. The Author(s).)

Amazonia's floodplain system is the largest and most biodiverse on Earth. Although forests are crucial to the ecological integrity of floodplains, our understanding of their species composition and how this may differ from surrounding forest types is still far too limited, particularly as changing inundation regimes begin to reshape floodplain tree communities and the critical ecosystem functions they underpin. Here we address this gap by taking a spatially explicit look at Amazonia-wide patterns of tree-species turnover and ecological specialization of the region's floodplain forests. We show that the majority of Amazonian tree species can inhabit floodplains, and about a sixth of Amazonian tree diversity is ecologically specialized on floodplains. The degree of specialization in floodplain communities is driven by regional flood patterns, with the most compositionally differentiated floodplain forests located centrally within the fluvial network and contingent on the most extraordinary flood magnitudes regionally. Our results provide a spatially explicit view of ecological specialization of floodplain forest communities and expose the need for whole-basin hydrological integrity to protect the Amazon's tree diversity and its function., (© 2024. The Author(s).)

Portal hypertension (PHT) is defined as an increase in pressure at the level of the portal vein above 5 mmHg, the most common cause being liver cirrhosis. Among the presinusoidal intrahepatic causes of PHT with portal venular involvement, what was traditionally known as idiopathic non-cirrhotic portal hypertension (NCIH) is described, with the requirements of excluding those patients who did not present PHT, as well as those with the presence of liver cirrhosis and thrombosis. portal venous vein (PVT). Currently, the diagnostic criteria for this entity have been reconsidered, and its name, being known as porto-sinusoidal vascular disease (PSVD), also does not exclude patients with PHT or the presence of underlying liver disease. Liver biopsy continues to be the gold standard for diagnosis. The clinical manifestations are derived from PHT and the management is similar to the complications that occur in patients with liver cirrhosis. The case of a male patient is presented who presents with symptoms of digestive bleeding, with findings of esophageal varices in upper endoscopy in addition to a study of viral, autoimmune liver disease and negative deposits, with a conclusive liver biopsy of porto-sinusoidal vascular disease.

In this study, dry dispersion laser diffraction was used to study the dispersibility of spheronized agglomerate formulations and identify geometric particle size metrics that correlated well with aerodynamic particle size distribution (APSD). Eleven unique batches of agglomerates were prepared for both laser diffraction and cascade impaction testing. Correlations between the particle size distribution (PSD) and aerodynamic particle size distribution (APSD) metrics for the eleven agglomerate batches were determined in a semi-empirical manner. The strongest correlation between APSD and PSD was observed between the impactor-sized mass (%ISM) and the cumulative PSD fraction <14.5 µm. The strongest correlation with fine particle fraction (FPF) was observed with the cumulative PSD fraction <0.99 micron (R-squared = 0.974). In contrast to the other APSD metrics, good correlations were not found between the mass median aerodynamic diameter (MMAD) and the cumulative PSD fractions. Overall, the implementation of laser diffraction as a surrogate for cascade impaction has the potential to streamline product development. Laser diffraction measurements offer savings in labor and turnaround time compared to cascade impaction., (© 2024. Merck & Co., Inc., Rahway, NJ, USA and its affiliates, under exclusive licence to American Association of Pharmaceutical Scientists.)

Forests are a substantial terrestrial carbon sink, but anthropogenic changes in land use and climate have considerably reduced the scale of this system 1 . Remote-sensing estimates to quantify carbon losses from global forests 2-5 are characterized by considerable uncertainty and we lack a comprehensive ground-sourced evaluation to benchmark these estimates. Here we combine several ground-sourced 6 and satellite-derived approaches 2,7,8 to evaluate the scale of the global forest carbon potential outside agricultural and urban lands. Despite regional variation, the predictions demonstrated remarkable consistency at a global scale, with only a 12% difference between the ground-sourced and satellite-derived estimates. At present, global forest carbon storage is markedly under the natural potential, with a total deficit of 226 Gt (model range = 151-363 Gt) in areas with low human footprint. Most (61%, 139 Gt C) of this potential is in areas with existing forests, in which ecosystem protection can allow forests to recover to maturity. The remaining 39% (87 Gt C) of potential lies in regions in which forests have been removed or fragmented. Although forests cannot be a substitute for emissions reductions, our results support the idea 2,3,9 that the conservation, restoration and sustainable management of diverse forests offer valuable contributions to meeting global climate and biodiversity targets., (© 2023. The Author(s).)

Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution., (© 2023. The Author(s).)

Understanding what controls global leaf type variation in trees is crucial for comprehending their role in terrestrial ecosystems, including carbon, water and nutrient dynamics. Yet our understanding of the factors influencing forest leaf types remains incomplete, leaving us uncertain about the global proportions of needle-leaved, broadleaved, evergreen and deciduous trees. To address these gaps, we conducted a global, ground-sourced assessment of forest leaf-type variation by integrating forest inventory data with comprehensive leaf form (broadleaf vs needle-leaf) and habit (evergreen vs deciduous) records. We found that global variation in leaf habit is primarily driven by isothermality and soil characteristics, while leaf form is predominantly driven by temperature. Given these relationships, we estimate that 38% of global tree individuals are needle-leaved evergreen, 29% are broadleaved evergreen, 27% are broadleaved deciduous and 5% are needle-leaved deciduous. The aboveground biomass distribution among these tree types is approximately 21% (126.4 Gt), 54% (335.7 Gt), 22% (136.2 Gt) and 3% (18.7 Gt), respectively. We further project that, depending on future emissions pathways, 17-34% of forested areas will experience climate conditions by the end of the century that currently support a different forest type, highlighting the intensification of climatic stress on existing forests. By quantifying the distribution of tree leaf types and their corresponding biomass, and identifying regions where climate change will exert greatest pressure on current leaf types, our results can help improve predictions of future terrestrial ecosystem functioning and carbon cycling., (© 2023. The Author(s).)

Indigenous societies are known to have occupied the Amazon basin for more than 12,000 years, but the scale of their influence on Amazonian forests remains uncertain. We report the discovery, using LIDAR (light detection and ranging) information from across the basin, of 24 previously undetected pre-Columbian earthworks beneath the forest canopy. Modeled distribution and abundance of large-scale archaeological sites across Amazonia suggest that between 10,272 and 23,648 sites remain to be discovered and that most will be found in the southwest. We also identified 53 domesticated tree species significantly associated with earthwork occurrence probability, likely suggesting past management practices. Closed-canopy forests across Amazonia are likely to contain thousands of undiscovered archaeological sites around which pre-Columbian societies actively modified forests, a discovery that opens opportunities for better understanding the magnitude of ancient human influence on Amazonia and its current state.

Determining the drivers of non-native plant invasions is critical for managing native ecosystems and limiting the spread of invasive species 1,2 . Tree invasions in particular have been relatively overlooked, even though they have the potential to transform ecosystems and economies 3,4 . Here, leveraging global tree databases 5-7 , we explore how the phylogenetic and functional diversity of native tree communities, human pressure and the environment influence the establishment of non-native tree species and the subsequent invasion severity. We find that anthropogenic factors are key to predicting whether a location is invaded, but that invasion severity is underpinned by native diversity, with higher diversity predicting lower invasion severity. Temperature and precipitation emerge as strong predictors of invasion strategy, with non-native species invading successfully when they are similar to the native community in cold or dry extremes. Yet, despite the influence of these ecological forces in determining invasion strategy, we find evidence that these patterns can be obscured by human activity, with lower ecological signal in areas with higher proximity to shipping ports. Our global perspective of non-native tree invasion highlights that human drivers influence non-native tree presence, and that native phylogenetic and functional diversity have a critical role in the establishment and spread of subsequent invasions., (© 2023. The Author(s).)

Background: Given the recent detection of tetrodotoxin (TTX) in bivalve molluscs but the absence of a full collaborative validation study for TTX determination in a large number of shellfish samples, interlaboratory assessment of method performance was required to better understand current capabilities for accurate and reproducible TTX quantitation using chemical and immunoassay methods., Objective: The aim was to conduct an interlaboratory study with multiple laboratories, using results to assess method performance and acceptability of different TTX testing methods., Methods: Homogenous and stable mussel and oyster materials were assessed by participants using a range of published and in-house detection methods to determine mean TTX concentrations. Data were used to calculate recoveries, repeatability, and reproducibility, together with participant acceptability z-scores., Results: Method performance characteristics were good, showing excellent sensitivity, recovery, and repeatability. Acceptable reproducibility was evidenced by HorRat values for all LC-MS/MS and ELISA methods being less than the 2.0 limit of acceptability. Method differences between the LC-MS/MS participants did not result in statistically different results. Method performance characteristics compared well with previously published single-laboratory validated methods and no statistical difference was found in results returned by ELISA in comparison with LC-MS/MS., Conclusion: The results from this study demonstrate that current LC-MS/MS methods and ELISA are on the whole capable of sensitive, accurate, and reproducible TTX quantitation in shellfish. Further work is recommended to expand the number of laboratories testing ELISA and to standardize an LC-MS/MS protocol to further improve interlaboratory precision., Highlights: Multiple mass spectrometric methods and a commercial ELISA have been successfully assessed through an interlaboratory study, demonstrating excellent performance., (© The Author(s) 2023. Published by Oxford University Press on behalf of AOAC INTERNATIONAL.)

Competing Interests: The authors declare that they have no conflict of interest.

The most common major adverse event of endoscopic mucosal resection (EMR) is clinically significant post-EMR bleeding (CSPEB), with an incidence of 6%-7% in large lesions. Repeat colonoscopy, blood transfusions, or other interventions are often needed. The associated direct costs are much higher than those of an uncomplicated EMR. In this review, we discuss the aspects related to CSPEB of large nonpedunculated polyps, such as risk factors, predictive models, and prophylactic measures, and we highlight evidence for preventive treatment options and explore new methods for bleeding prophylaxis. We also provide recommendations for steps that can be taken before, during, and after EMR to minimize bleeding risk. Finally, this review proposes future directions to reduce CSPEB incidence., (Copyright © 2022 by The American College of Gastroenterology.)

Gastroesophageal reflux disease has an increasing incidence and prevalence worldwide. A significant proportion of patients have a suboptimal response to proton pump inhibitors or are unwilling to take lifelong medication due to concerns about long-term adverse effects. Endoscopic anti-reflux therapies offer a minimally invasive option for patients unwilling to undergo surgical treatment or take lifelong medication. The best candidates are those with a good response to proton pump inhibitors and without a significant sliding hiatal hernia. Transoral incisionless fundoplication and nonablative radiofrequency are the techniques with the largest body of evidence and that have been tested in several randomized clinical trials. Band-assisted ligation techniques, anti-reflux mucosectomy, anti-reflux mucosal ablation, and new plication devices have yielded promising results in recent noncontrolled studies. Nonetheless, the role of endoscopic procedures remains controversial due to limited long-term and comparative data, and no consensus exists in current clinical guidelines. This review provides an updated summary focused on the patient selection, technical details, clinical success, and safety of current and future endoscopic anti-reflux techniques., Competing Interests: Conflict-of-interest statement: The authors declare no conflicts of interest for this article., (©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.)

Amazonian forests are extraordinarily diverse, but the estimated species richness is very much debated. Here, we apply an ensemble of parametric estimators and a novel technique that includes conspecific spatial aggregation to an extended database of forest plots with up-to-date taxonomy. We show that the species abundance distribution of Amazonia is best approximated by a logseries with aggregated individuals, where aggregation increases with rarity. By averaging several methods to estimate total richness, we confirm that over 15,000 tree species are expected to occur in Amazonia. We also show that using ten times the number of plots would result in an increase to just ~50% of those 15,000 estimated species. To get a more complete sample of all tree species, rigorous field campaigns may be needed but the number of trees in Amazonia will remain an estimate for years to come.

A major shortcoming of drug nanocomposites as compared with amorphous solid dispersions (ASDs) is their limited supersaturation capability in dissolution media. Here, we prepared drug hybrid nanocrystal-amorphous solid dispersions (HyNASDs) and compare their performance to ASDs. A wet-milled griseofulvin (GF, BCS II drug) nanosuspension and a GF solution, both containing the same dissolved polymer-surfactant (SDS: sodium dodecyl sulfate) with 1:1 and 1:3 GF:polymer mass ratios, were spray-dried. Hydroxypropyl cellulose (HPC) and Soluplus (Sol) were used as matrix-forming polymers. XRPD, DSC, and Raman spectroscopy reveal that ASDs were formed upon spray-drying the solution-based feed, whereas nanocomposites and nanocomposites with >10% amorphous content, HyNASDs, were formed with the nanosuspension-based feed. Sol provided higher GF relative supersaturation, up to 180% and 360% for HyNASDs and ASDs, respectively, in the dissolution tests than HPC (up to 50% for both) owing to Sol's stronger intermolecular interactions and miscibility with GF and its recrystallization inhibition. Besides the higher kinetic solubility of GF in Sol, presence of GF nanoparticles vs. micron-sized particles in the nanocomposites enabled fast supersaturation. This study demonstrates successful preparation of fast supersaturating (190% within 20 min) HyNASDs, which renders nanoparticle formulations competitive to ASDs in bioavailability enhancement of poorly soluble drugs., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such "monodominant" forests are known from all of the main tropical regions. For Amazonia, we sampled the occurrence of monodominance in a massive, basin-wide database of forest-inventory plots from the Amazon Tree Diversity Network (ATDN). Utilizing a simple defining metric of at least half of the trees ≥ 10 cm diameter belonging to one species, we found only a few occurrences of monodominance in Amazonia, and the phenomenon was not significantly linked to previously hypothesized life history traits such wood density, seed mass, ectomycorrhizal associations, or Rhizobium nodulation. In our analysis, coppicing (the formation of sprouts at the base of the tree or on roots) was the only trait significantly linked to monodominance. While at specific locales coppicing or ectomycorrhizal associations may confer a considerable advantage to a tree species and lead to its monodominance, very few species have these traits. Mining of the ATDN dataset suggests that monodominance is quite rare in Amazonia, and may be linked primarily to edaphic factors.

Background: Irritable bowel syndrome (IBS) is a highly prevalent condition. It is diagnosed on the basis of chronic symptoms after the clinical and/or investigative exclusion of organic diseases that can cause similar symptoms. There is no reproducible non-invasive test for the diagnosis of IBS, and this raises diagnostic uncertainty among physicians and hinders acceptance of the diagnosis by patients. Functional gastrointestinal (GI) syndromes often present with overlapping upper and lower GI tract symptoms, now believed to be generated by visceral hypersensitivity. This study examines the possibility that, in IBS, a nutrient drink test (NDT) provokes GI symptoms that allow a positive differentiation of these patients from healthy subjects., Aim: To evaluate the NDT for the diagnosis of IBS., Methods: This prospective case-control study compared the effect of two different nutrient drinks on GI symptoms in 10 IBS patients (patients) and 10 healthy controls (controls). The 500 kcal high nutrient drink and the low nutrient 250 kcal drink were given in randomized order on separate days. Symptoms were assessed just before and at several time points after drink ingestion. Global dyspepsia and abdominal scores were derived from individual symptom data recorded by two questionnaires designed by our group, the upper and the general GI symptom questionnaires, respectively. Psycho-social morbidity and quality of life were also formally assessed. The scores of patients and controls were compared using single factor analysis of variance test., Results: At baseline, IBS patients compared to controls had significantly higher levels of GI symptoms such as gastro-esophageal reflux ( P = 0.05), abdominal pain ( P = 0.001), dyspepsia ( P = 0.001), diarrhea ( P = 0.001), and constipation ( P = 0.001) as well as higher psycho-social morbidity and lower quality of life. The very low incidence of GI symptoms reported by control subjects did not differ significantly for the two test drinks. Compared with the low nutrient drink, IBS patients with the high nutrient drink had significantly more dyspeptic symptoms at 30 ( P = 0.014), 45 ( P = 0.002), 60 ( P = 0.001), and 120 min ( P = 0.011). Dyspeptic symptoms triggered by the high nutrient drink during the first 120 min gave the best differentiation between healthy controls and patients (area under receiver operating curve of 0.915 at 45 min for the dyspepsia score). Continued symptom monitoring for 24 h did not enhance separation of patients from controls., Conclusion: A high NDT merits further evaluation as a diagnostic tool for IBS., Competing Interests: Conflict-of-interest statement: None of the authors have conflicts of interest to be declared.

The extent to which pre-Columbian societies altered Amazonian landscapes is hotly debated. We performed a basin-wide analysis of pre-Columbian impacts on Amazonian forests by overlaying known archaeological sites in Amazonia with the distributions and abundances of 85 woody species domesticated by pre-Columbian peoples. Domesticated species are five times more likely than nondomesticated species to be hyperdominant. Across the basin, the relative abundance and richness of domesticated species increase in forests on and around archaeological sites. In southwestern and eastern Amazonia, distance to archaeological sites strongly influences the relative abundance and richness of domesticated species. Our analyses indicate that modern tree communities in Amazonia are structured to an important extent by a long history of plant domestication by Amazonian peoples., (Copyright © 2017, American Association for the Advancement of Science.)

Purpose: To compare the incidence, microbial profile, management and outcomes of endophthalmitis after glaucoma drainage implant (GDI), or trabeculectomy over 2 separate time periods before and after the year 2000., Methods: A chart review was performed for patients with endophthalmitis after trabeculectomy (trabeculectomy group) or GDI group between 1983 to 1999 (group 1) and 2000 to 2011 (group 2) at a tertiary care hospital. Data were compared between groups and time periods., Results: There were 56 cases of endophthalmitis after trabeculectomy in group 1 and 17 cases in group 2. After GDI, there were 10 cases of endophthalmitis in group 1 and 1 case in group 2. The incidence of endophthalmitis after GDI decreased significantly from 0.0105% to 0.00074% in groups 1 and 2, respectively (P<0.05). The incidence of endophthalmitis decreased significantly after trabeculectomy from 0.007% in group 1 to 0.00197% in group 2 (P=0.0004). There were 26 culture-positive cases in group 1 and 10 in group 2. The most common isolates were Streptococcus species in group 1 and Staphylococcus species in group 2. Indicators of morbidity were lower in group 2. The final visual outcome in either group was not correlated to the type of surgery, microbes, or initial management., Conclusions: There was a greater incidence of endophthalmitis after trabeculectomy compared with GDI. The incidence of endophthalmitis decreased from 2001 to 2011 compared with 1983 to 1999, which is likely due to advances in surgical technique. However, significant visual morbidity does occur despite prompt treatment.

Introduction: Voluntary muscle activity, including swallowing, decreases during the night. The association between nocturnal awakenings and swallowing activity is under-researched with limited information on the frequency of swallows during awake and asleep periods., Aim: The aim of this study was to assess nocturnal swallowing activity and identify a cut-off predicting awake and asleep periods., Methods: Patients undergoing impedance-pH monitoring as part of GERD work-up were asked to wear a wrist activity detecting device (Actigraph(®)) at night. Swallowing activity was quantified by analysing impedance changes in the proximal esophagus. Awake and asleep periods were determined using a validated scoring system (Sadeh algorithm). Receiver operating characteristics (ROC) analyses were performed to determine sensitivity, specificity and accuracy of swallowing frequency to identify awake and asleep periods., Results: Data from 76 patients (28 male, 48 female; mean age 56 ± 15 years) were included in the analysis. The ROC analysis found that 0.33 sw/min (i.e. one swallow every 3 min) had the optimal sensitivity (78 %) and specificity (76 %) to differentiate awake from asleep periods. A swallowing frequency of 0.25 sw/min (i.e. one swallow every 4 min) was 93 % sensitive and 57 % specific to identify awake periods. A swallowing frequency of 1 sw/min was 20 % sensitive but 96 % specific in identifying awake periods. Impedance-pH monitoring detects differences in swallowing activity during awake and asleep periods. Swallowing frequency noticed during ambulatory impedance-pH monitoring can predict the state of consciousness during nocturnal periods.

Hypothesis: The mechanisms underlying impairment of dynamic cerebral autoregulation in diabetes are not well known. Cardiovascular autonomic neuropathy (CAN) could contribute to dynamic cerebral autoregulation impairment. In this study, we assessed the association between CAN and impairment of dynamic cerebral autoregulation in patients with type 1 diabetes., Methods: We evaluated dynamic cerebral autoregulation (DCA) in patients with type 1 diabetes and no history of cerebrovascular disease. DCA was assessed with transcranial Doppler using the correlation coefficient index Mx method. Mx was calculated from slow changes in mean cerebral blood flow velocity and mean arterial blood pressure. Increase in Mx indicates weaker DCA, with a threshold for impaired DCA above 0.3. Moderate CAN was defined as reduced heart rate variability (HRV) on the following tests: deep controlled breathing, Valsalva maneuver or initiation of active standing. Severe CAN was defined as reduced HRV associated with orthostatic hypotension., Results: 60 patients were included (M/F: 33/27; mean age ± SD: 46 years ± 11.5). 23 patients had moderate CAN and 15 patients severe CAN. DCA was impaired in 37 patients. CAN was associated with impaired DCA (p = 0.005). Impairment of DCA was more pronounced in patients with severe CAN (p = 0.019). Glycosylated haemoglobin (HbA1c) was associated with impaired DCA in univariate analysis (p = 0.05). In multivariate analysis, only CAN was associated with impaired DCA (p = 0.007) whereas HbA1c was not (p = 0.161)., Conclusions: CAN was associated with impaired DCA in type 1 diabetes. The magnitude of DCA impairment increased with the severity of CAN., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Objective: To determine the effectiveness of a low-dose intravitreal injection of autologous plasmin enzyme (APE), without the performance of a vitrectomy, as a treatment for refractory diffuse diabetic macular edema (DDME)., Design: Prospective, comparative, interventional case series., Patients: Sixteen patients with bilateral DDME who had not responded to prior laser photocoagulation. All patients received an injection in 1 eye, while the other eye served as a control., Intervention: Intravitreal 0.2 mL APE injection under topical anesthesia. The APE was obtained using a simplified method., Main Outcome Measures: Central macular thickness (CMT) at 1 and 6 months, determined by optical coherence tomography (OCT) and best corrected visual acuity (BCVA)., Results: All patients underwent a 1-month follow-up. Prior to injection, CMT in the eye about to receive the injection was 541 +/- 79 microm (mean +/- standard deviation [SD]) versus 535 +/- 76 microm in the control eye. One month after injection, CMT was 241 +/- 47 microm in injected eyes and 530 +/- 85 microm in control eyes (P < 0.001, bilateral Wilcoxon test for paired samples). The macular edema (ME) improved in all injected eyes (100%), with complete resolution in 7 patients (44%). The mean BCVA of treated eyes was 0.618 +/- 0.27 (mean +/- SD) at baseline and 0.45 +/- 0.24 four weeks after injection (paired samples t-test, P < 0.001). No adverse effects were observed in any of the patients. BCVA and CMT were stable when evaluated at 6-month follow-up (0.43 +/- 0.242 and 244 +/- 46 microm, respectively)., Conclusions: Intravitreal APE injection effectively reduces macular thickening due to DDME in cases that fail to respond to conventional laser photocoagulation, and improves visual acuity in a short term, and this results remain stable in a medium term what is very important. Further investigation is warranted in order to assess long-term efficacy and safety.

Southern cattle tick, Boophilus microplus, control in the Mexican tropics is based on the application by spray, dip or pour-on of acaricides. In Mexico the first report of ticks resistant to amitraz was reported in 2002. Amitraz resistance affecting the cattle industry of Yucatan State, Mexico, has not been investigated. A cross-sectional study was carried out in order to investigate the possible association between management risk factors and the prevalence of B. microplus ticks resistant to amitraz in Yucatan, Mexico. Ninety-eight cattle farms were randomly selected and a sample of 20-30 engorged B. microplus females was collected from at least 10 cattle from each farm. Collected ticks were taken to the laboratory where the larval progeny were obtained. The modified larval immersion test was used to detect ticks resistant to amitraz. A discriminating dose of 0.0002% amitraz was used. A questionnaire was applied on each collaborating farm. For the statistical analysis a 2x2 contingency table was used to identify potential risk factors. The prevalence of farms with B. microplus resistant to amitraz was 19.40%. However, even though tick resistance to amitraz is a present problem there was no evidence that it was associated with the risk factors analyzed in this survey.

A cross-sectional study was carried out in order to investigate the association between management risk factors and the prevalence of organophosphate (OP) and synthetic pyrethroid (SP) resistance in Boophilus microplus ticks in Yucatan State, Mexico. Ninety-eight cattle ranches were randomly selected and a sample of 20-30 engorged female B. microplus ticks was collected at each. The modified larvae packet test was used to detect OP and SP tick resistance. A questionnaire was administered on each ranch. For risk factors, four reference types of response were used: Tuxpan (resistant to coumaphos, chlorfenvinphos and diazinon), Parkhurst (resistant to flumethrin, deltamethrin and cypermethrin), Lamington (resistant to flumethrin in absence of deltamethrin and cypermethrin) and Marmor (resistant to flumethrin and cypermethrin in absence of flumethrin). A primary screening was performed using 2 x 2 contingency tables of exposure variables. All variables with p < or = 0.20 were analyzed by a logistic regression. The prevalence of B. microplus resistance to OP and SP groups were 83.70% and 66.32%, respectively. The prevalence for a single chemical compound was: diazinon (80.60%), coumaphos (45.90%), chlorfenvinphos (35.70%), flumethrin (63.28%), deltamethrin (61.22%), and cypermethrin (59.18%). The prevalence type of response was: Tuxpan (34.16%), Parkhurst (58.16%), Lamington (4.08%), and Marmor (4.08%). The use of a different tick control program was the risk management factor associated with the Parkhurst type of response. It is concluded that the prevalence of cattle ranches with B. microplus resistant to OPs and SPs in Yucatan, Mexico, is a current problem, and a treatment interval of > or =6 times/year and use of a tick control program (macrocyclic lactones and pasture burn) different from standard recommended programs are risk factors associated with the Parkhurst type of response.

There is a paucity of HIV autopsy data from South America and none that document the postmortem findings in patients with HIV/AIDS in Peru. The purpose of this autopsy study was to determine the spectrum of opportunistic infections and the causes of mortality in HIV-positive patients at a public hospital in Lima. Clinico-epidemiological information regarding HIV infection in Peru is also reviewed. Sixteen HIV-related hospital postmortems, performed between 1999 and 2004, were included in this retrospective analysis. The primary cause of death was established in 12 patients: one died of neoplasia and 11 of infectious diseases, including 3 from pulmonary infection, 7 from disseminated infection, and 2 from central nervous system infection (one case had dual pathology). Opportunistic infections were identified in 14 cases, comprising cytomegalovirus, histoplasmosis, cryptococcosis, toxoplasmosis, Pneumocystis pneumonia, aspergillosis, tuberculosis, varicella zoster virus, and cryptosporidiosis. Fourteen patients had at least one AIDS-related disease that had been neither clinically suspected nor diagnosed premortem. Moreover, 82% of the diagnoses considered to be of important clinical significance had not been suspected antemortem. The spectrum and frequency of certain opportunistic infections differed from other South American autopsy studies, highlighting the importance of performing HIV/AIDS postmortems in resource-limited countries where locally specific disease patterns may be observed.

Background/purpose: The organoid nevus (sebaceous nevus) syndrome is characterized primarily by cutaneous sebaceous nevus, seizures, and epibulbar choristomas. On the basis of ophthalmoscopic and computed tomographic studies, a yellow fundus lesion recently observed in this syndrome has been called a coloboma by some investigators and a choroidal osteoma by others. This study was undertaken to review our personal experience with the organoid nevus syndrome, to review the English language literature on the subject, and to address some misconceptions regarding its ocular manifestations., Methods: We reviewed the records of patients with the organoid nevus syndrome who were personally evaluated by the investigators. The ocular findings were studied in more detail, with emphasis on the epibulbar and fundus lesions., Results: We identified five patients with the organoid nevus syndrome. Four had a classic sebaceous nevus in the facial and scalp area, and 2 had seizures and arachnoid cysts. All 5 patients had an epibulbar tumor, which proved to be a complex choristoma in one case that was studied histopathologically. A characteristic ophthalmoscopic feature, observed in the 4 patients with clear ocular media, was a flat yellow discoloration of the posterior fundus, of variable size and shape, which appeared to correlate with a dense plaque noted on ultrasonography and computed tomography. In 1 case, histopathologic examination showed that this posterior lesion contained intrascleral cartilage., Conclusions: Our observations and a review of the literature indicated that the organoid nevus syndrome has varied manifestations. Like the closely related phakomatoses, it often occurs as a forme fruste, without full expression of the syndrome. The most important ocular manifestations are an epibulbar mass, compatible with a complex choristoma, and focal yellow discoloration in the fundus, probably related to intrascleral cartilage.

Purpose: To determine if scleral buckling is of any benefit in surgical repair of cytomegalovirus (CMV)-associated retinal detachment if combined with vitrectomy, silicone oil, and inferior midperipheral endolaser., Materials and Methods: Twenty-two consecutive eyes with CMV-associated retinal detachments were repaired with vitrectomy and endolaser to all breaks and to the inferior midperipheral retina using silicone oil without scleral buckling (group 1, control group) between July 1987 and May 1992. Results were compared with another series of 56 consecutive eyes undergoing vitrectomy, silicone oil injection, endolaser to all breaks, and 360 degrees encircling scleral buckling (group 2, study group) between June 1992 and July 1993., Results: Total retinal reattachment rates were 84% for group 1 and 86% for group 2. Rates of macular reattachment were 91% for group 1 and 91% for group 2. Mean best postoperative refracted visual acuity was 20/66 for group 1 and 20/67 for group 2. Median best postoperative refracted visual acuity was 20/74 for group 1 and 20/80 for group 2. These differences in results between the two groups were not statistically significant. Mean postoperative refractive error was +3.95 for group 1 and +4.92 for group 2. Patients who underwent surgery with the macula attached had a better postoperative visual outcome., Conclusion: Scleral buckling may not be necessary in CMV-related retinal detachment if repaired with vitrectomy, silicone oil, and inferior midperipheral endolaser. Elimination of scleral buckling may reduce intraoperative time, patient morbidity, and the risk of an accidental needle stick. Patients with macula-on retinal detachments also should be considered for surgery before macular detachment.

New data on the properties of red blood cells (RBC) cross-linked with glutaraldehyde are presented (see also Biochem. Biophys. Res. Commun., 1988, 156, 970-977). Equilibrium and kinetic data show that by carrying out the fixation procedure in the absence of oxygen but in the presence of allosteric effectors (e.g., stabilizing the low-affinity (T) quaternary state of hemoglobin), it is possible to maintain, at least in part, the biochemical functions of the crosslinked hemoglobin inside the cell. Moreover, we show that the oxygen affinity of fixed red blood cells (RBC) is still modulated, even though to a smaller degree, by the allosteric effector bezafibrate (BZF), which is able to cross the fixed RBC membrane. Membrane filtration experiments indicate that the higher rigidity of fixed RBC alters significantly their rheodynamic properties and show that in order to exploit "engineered" RBC as "blood substitutes," more flexible cross-linking reagents may offer significant advantages.

The ligand-binding properties of hemoglobins from two homozygote phenotypes (AA and BB) of water buffalo (Bubalus bubalis) have been characterized by equilibrium and kinetic techniques. In the case of the BB phenotype, the two constituent hemoglobins have been purified and separately analysed. Buffalo hemoglobins display the reduced sensitivity to organic phosphates characteristic of ruminant hemoglobins, their physiological effector probably being the chloride ion. In contrast to the other known hemoglobins from ruminants, all the hemoglobins from the water buffalo display a significant temperature sensitivity, the delta H for oxygen binding in the presence of physiological effectors approaching that of human hemoglobin (delta H = -30.5 kJ/mol O2). This discrepancy with the other ruminant hemoglobins (e.g. ox, delta H = -10.4 kJ/mol O2), whose primary structure is very similar to that of buffalo, hemoglobins might be correlated to the different habitat and phylogenetic history of the two subfamilies (Bos and Bubalus) of Bovidae.

Two cases of bilateral subclavian steal syndrome are presented, demonstrating complete occlusion at the origin of both subclavian arteries with distal reconstitution via reversal of blood flow through the vertebrobasilar system. Since unsuspected subclavian artery obstruction may present significant angiographic hazard, careful physical examination including blood pressures in both upper extremities and auscultation of the neck is necessary in order to avoid undesirable complications.

The use and value of a relatively new diagnostic modality, ultrasound, in the diagnosis of renal masses are discussed. Several examples are presented.