Concordance of in vivo reflectance confocal microscopy and horizontal-sectioning histology in skin tumours

BACKGROUND

In vivo reflectance confocal microscopy (RCM) enables the study of architectural and cytological aspects in horizontal sections, which closely correlate with histologic features. However, traditional histopathological vertical sections cannot totally reproduce the image of the in vivo RCM horizontal section.

OBJECTIVE

To evaluate the concordance between in vivo RCM and histopathologic transverse sections for melanocytic lesions, basal cell carcinoma and seborrheic keratoses.

METHODS

Prospectively collected benign melanocytic and non-melanocytic tumours diagnosed by dermoscopy were evaluated for common RCM features and compared to histopathology in horizontal sections with haematoxylin and eosin staining.

RESULTS

A total of 44 skin tumours including 19 melanocytic lesions (nine compound, five junctional and five intradermal nevi), 12 basal cell carcinomas and 13 seborrheic keratoses were collected in the Department of Dermatology of Hospital Clinic of Barcelona. The RCM features that had statistically significant agreement with the histopathological horizontal sections were the preserved and visible honeycomb pattern, well defined DEJ, small bright particles, dermal nests, tumour islands and dark silhouettes, clefting, collagen bundles, thickened collagen bundles and cytologic atypia.

CONCLUSIONS

Histopathology evaluation of horizontal sections of skin tumours can be correlated with main RCM findings. The results of this study have improved the understanding and interpretation of RCM features in relation to skin tumours, thus reinforcing the utility of RCM as a diagnostic tool.

Genomics of Re-Emergent Aeromonas salmonicida in Atlantic Salmon Outbreaks

Furunculosis, caused by Aeromonas salmonicida, poses a significant threat to both salmonid and non-salmonid fish in diverse aquatic environments. This study explores the genomic intricacies of re-emergent A. salmonicida outbreaks in Atlantic salmon (Salmo salar). Previous clinical cases have exhibited pathological characteristics, such as periorbital hemorrhages and gastrointestinal abnormalities. Genomic sequencing of three Chilean isolates (ASA04, ASA05, and CIBA_5017) and 25 previously described genomes determined the pan-genome, phylogenomics, insertion sequences, and restriction-modification systems. Unique gene families have contributed to an improved understanding of the psychrophilic and mesophilic clades, while phylogenomic analysis has been used to identify mesophilic and psychrophilic strains, thereby further differentiating between typical and atypical psychrophilic isolates. Diverse insertion sequences and restriction-modification patterns have highlighted genomic structural differences, and virulence factor predictions can emphasize exotoxin disparities, especially between psychrophilic and mesophilic strains. Thus, a novel plasmid was characterized which emphasized the role of plasmids in virulence and antibiotic resistance. The analysis of antibiotic resistance factors revealed resistance against various drug classes in Chilean strains. Overall, this study elucidates the genomic dynamics of re-emergent A. salmonicida and provides novel insights into their virulence, antibiotic resistance, and population structure.

VMAT-IGRT Hypofractionated Radiotherapy for Locally Advanced Thyroid Cancer in Resource-Limited Settings: A Retrospective Report from Bolivia

PURPOSE/OBJECTIVE(S)

This study evaluated the efficacy and safety of hypofractionated external beam irradiation with VMAT-IGRT in patients with locally advanced thyroid cancer (LATC) who are ineligible for surgery or I-131 in a resource-limited setting such as Bolivia.

MATERIALS/METHODS

Thirty-three patients were treated with H-VMAT-IGRT between August 2018 and November 2022. Axial CT images were acquired every 3 mm from the base of the skull to the middle of the chest. GTV was determined based on contrast-enhanced tumor on T1 MRI or CT scans. CTV 55 Gy at 2.75 Gy was defined based on visible residual tumor and included dissected nodal stations with pathologically positive nodes. CTV 44 at 2.2 Gy for non-dissected nodal stations with low risk of recurrence, we escalated the dose up to 60 Gy at 3 Gy for small tumors up to 20 cc. PTVs were created by adding a 0.3 cm margin around CTVs, with a reduced margin of minus 3-5 mm for critical organs such as esophagus, pharynx, and brachial plexus. Equivalent dose in 2Gy (EQD2 10-3) was reported for tumor control and OAR constraints. Acute toxicity was reported according to RTOG criteria, and response to treatment was assessed at baseline, end of treatment, and every third month thereafter.

RESULTS

The mean time since last follow-up was 24 months (r: 8-40). Patients were 80% female and 20% male. The mean age was 50 years (r: 29-72). Local recurrence was treated in 52% (13) of patients and LATC in 48% (12). Papillary carcinomas accounted for 68% of patients, followed by anaplastic (24%) and follicular (8%) carcinomas. Tumors were classified according to the AJCC classification. Of the patients treated for LATC, 25% were at stage II, 25% at stage III, 16.67% at stage IVA, and 33.33% at stage IVB. Among patients treated for local recurrence, the initial stage before progression was stage I in 61.5%, stage II in 30.8%, and stage IVA in 7.7%. The median PTV was 383.8 cc (r: 51.7 - 627.3) and the median CTV55 was 189.2 cc (r: 39.6 - 519.8). Grade 1 (10%), Grade 2 (90%) dysphagia, Grade 1 (40%), Grade 2 (60%) acute pharyngeal mucositis, and no Grade 3 acute toxicity were observed. No reports of chronic upper damage GI, 30% xerostomia G2. Two-year local control was 70% and overall survival was also 70%.

CONCLUSION

We suggest that reducing treatment duration while maintaining efficacy is particularly beneficial in resource-limited areas with a shortage of trained personnel and overburdened treatment centers. We report good local control rates with no detrimental effects on quality of life with hypofractionation. No evidence of delayed damage, such as spinal cord dysfunction, mandibular osteoradionecrosis, or brachial plexopathy, was noted. We emphasize the importance of using VMAT with IGRT for reliable and accurate daily treatment of the target area, while minimizing side effects. However, these results should be confirmed with a larger sample of patients.

Multisystemic inflammatory syndrome related to COVID-19, with latent tuberculosis in bone marrow, and satisfactory response to tocilizumab, in a 7-year-old boy

Paediatric inflammatory multisystem syndrome temporally associated with COVID-19 (PIMS-TS) or multisystem inflammatory syndrome in children (MIS-C) is a new acute-onset systemic inflammatory disease, which mainly affects children. Latent tuberculosis infection (LTBI) is characterized by the presence of immune sensitization to Mycobacterium tuberculosis (MTB) in the absence of any clinical or radiological evidence of active disease. We present a child with MIS-C related to COVID-19, with latent TB in the bone marrow, and satisfactory response to tocilizumab. It is important to pay attention in the investigation of TB cases in countries with a high prevalence of tuberculosis, especially when opting for immunusuppression.

Disentangling the environmental processes responsible for the world's largest farmed fish-killing harmful algal bloom: Chile, 2016

The dictyochophyte microalga Pseudochattonella verruculosa was responsible for the largest farmed fish mortality ever recorded in the world, with losses for the Chilean salmon industry amounting to US$ 800 M in austral summer 2016. Super-scale climatic anomalies resulted in strong vertical water column stratification that stimulated development of a dynamic P. verruculosa thin layer (up to 38 μg chl a L^-1) for several weeks in Reloncaví Sound. Hydrodynamic modeling (MIKE 3D) indicated that the Sound had extremely low flushing rates (between 121 and 200 days) in summer 2016. Reported algal cell densities of 7000-20,000 cells mL^-1 generated respiratory distress in fish that was unlikely due to low dissolved oxygen (permanently >4 mg L^-1). Histological examination of salmon showed that gills were the most affected organ with significant tissue damage and circulatory disorders. It is possible that some of this damage was due to a diatom bloom that preceded the Pseudochattonella event, thereby rendering the fish more susceptible to Pseudochattonella. No correlation between magnitude of fish mortality and algal cell abundance nor fish age was evident. Algal cultures revealed rapid growth rates and high cell densities (up to 600,000 cells mL^-1), as well as highly complex life cycle stages that can be easily overlooked in monitoring programs. In cell-based bioassays, Chilean P. verruculosa was only toxic to the RTgill-W1 cell line following exposures to high cell densities of lysed cells (>100,000 cells mL^-1). Fatty acid profiles of a cultured strain showed elevated concentrations of potentially ichthyotoxic, long-chain polyunsaturated fatty acids (PUFAs) (69.7% ± 1.8%)- stearidonic (SDA, 18:4ω3-28.9%), and docosahexaenoic acid (DHA, 22:6ω3-22.3%), suggesting that lipid peroxidation may help to explain the mortalities, though superoxide production by Pseudochattonella was low (< 0.21 ± 0.19 pmol O₂^- cell^-1 h^-1). It therefore remains unknown what the mechanisms of salmon mortality were during the Pseudochattonella bloom. Multiple mitigation strategies were used by salmon farmers during the event, with only delayed seeding of juvenile fish into the cages and towing of cages to sanctuary sites being effective. Airlift pumping, used effectively against other fish-killing HABs in the US and Canada was not effective, perhaps because it brought subsurface layers of Pseudochattonella to the surface, or and it also may have lysed the fragile cells, rendering them more lethal. The present study highlights knowledge gaps and inefficiency of contingency plans by the fish farming industry to overcome future fish-killing algal blooms under future climate change scenarios. The use of new technologies based on molecular methods for species detection, good farm practices by fish farms, and possible mitigation strategies are discussed.

Migration of noble gas tracers at the site of an underground nuclear explosion at the Nevada National Security Site

As part of an underground gas migration study, two radioactive noble gases (³⁷Ar and ¹²⁷Xe) and two stable tracer gases (SF₆ and PFDMCH) were injected into a historic nuclear explosion test chimney and allowed to migrate naturally. The purpose of this experiment was to provide a bounding case (natural transport) for the flow of radioactive noble gases following an underground nuclear explosion. To accomplish this, soil gas samples were collected from a series of boreholes and a range of depths from the shallow subsurface (3 m) to deeper levels (~160 m) over a period of eleven months. These samples have provided insights into the development and evolution of the subsurface plume and constrained the relative migration rates of the radioactive and stable gas species in the case when the driving pressure from the cavity is low. Analysis of the samples concluded that the stable tracer SF₆ was consistently enriched in the subsurface samples relative to the radiotracer ¹²⁷Xe, but the ratios of SF₆ and ³⁷Ar remained similar throughout the samples.

Genomic epidemiology of the commercially important pathogen Renibacterium salmoninarum within the Chilean salmon industry

Renibacterium salmoninarum is the causative agent of bacterial kidney disease (BKD), which is a commercially important disease of farmed salmonids. Typing by conventional methods provides limited information on the evolution and spread of this pathogen, as there is a low level of standing variation within the R. salmoninarum population. Here, we apply whole-genome sequencing to 42 R. salmoninarum isolates from Chile, primarily from salmon farms, in order to understand the epidemiology of BKD in this country. The patterns of genomic variation are consistent with multiple introductions to Chile, followed by rapid dissemination over a 30 year period. The estimated dates of introduction broadly coincide with major events in the development of the Chilean aquaculture industry. We find evidence for significant barriers to transmission of BKD in the Chilean salmon production chain that may also be explained by previously undescribed signals of host tropism in R. salmoninarum. Understanding the genomic epidemiology of BKD can inform disease intervention and improve sustainability of the economically important salmon industry. This article contains data hosted by Microreact.

Measurements of Argon-39 at the U20az underground nuclear explosion site

Pacific Northwest National Laboratory reports on the detection of ³⁹Ar at the location of an underground nuclear explosion on the Nevada Nuclear Security Site. The presence of ³⁹Ar was not anticipated at the outset of the experimental campaign but results from this work demonstrated that it is present, along with ³⁷Ar and ⁸⁵Kr in the subsurface at the site of an underground nuclear explosion. Our analysis showed that by using state-of-the-art technology optimized for radioargon measurements, it was difficult to distinguish ³⁹Ar from the fission product ⁸⁵Kr. Proportional counters are currently used for high-sensitivity measurement of ³⁷Ar and ³⁹Ar. Physical and chemical separation processes are used to separate argon from air or soil gas, yielding pure argon with contaminant gases reduced to the parts-per-million level or below. However, even with purification at these levels, the beta decay signature of ⁸⁵Kr can be mistaken for that of ³⁹Ar, and the presence of either isotope increases the measurement background level for the measurement of ³⁷Ar. Measured values for the ³⁹Ar measured at the site ranged from 36,000 milli- Becquerel/standard-cubic-meter-of-air (mBq/SCM) for shallow bore holes to 997,000 mBq/SCM from the rubble chimney from the underground nuclear explosion.

First description of clinical presentation of piscine orthoreovirus (PRV) infections in salmonid aquaculture in Chile and identification of a second genotype (Genotype II) of PRV

BACKGROUND

Heart and skeletal muscle inflammation (HSMI) is an emerging disease of marine-farmed Atlantic salmon Salmo salar, first recognized in 1999 in Norway, and recently associated with piscine orthoreovirus (PRV) infection. To date, HSMI lesions with presence of PRV have only been described in marine-farmed Atlantic salmon in Norway. A new HSMI-like disease in rainbow trout Oncorhynchus mykiss associated with a PRV-related virus has also been reported in Norway.

METHODS

Sampling of Atlantic salmon and coho salmon was done during potential disease outbreaks, targeting lethargic/moribund fish. Fish were necropsied and tissues were taken for histopathologic analysis and testing for PRV by RT-qPCR assay for segment L1 and conventional RT-PCR for PRV segment S1. The PCR products were sequenced and their relationship to PRV strains in GenBank was determined using phylogenetic analysis and nucleotide and amino acid homology comparisons.

RESULTS

The Atlantic salmon manifested the classical presentation of HSMI with high PRV virus loads (low Ct values) as described in Norway. The coho salmon with low Ct values had myocarditis but only in the spongy layer, the myositis of red muscle in general was mild, and the hepatic necrosis was severe. Upon phylogenetic analysis of PRV segment S1 sequences, all the Chilean PRV strains from Atlantic salmon grouped as sub-genotype Ib, whereas the Chilean PRV strains from coho salmon were more diversified, grouping in both sub-genotypes Ia and Ib and others forming a distinct new phylogenetic cluster, designated Genotype II that included the Norwegian PRV-related virus.

CONCLUSIONS

To our knowledge the present work constitutes the first published report of HSMI lesions with presence of PRV in farmed Atlantic salmon outside of Europe, and the first report of HSMI-like lesions with presence of PRV in coho salmon in Chile. The Chilean PRV strains from coho salmon are more genetically diversified than those from Atlantic salmon, and some form a distinct new phylogenetic cluster, designated Genotype II.

Core Content for Undergraduate Medical Education in Spain: Recommendations of the Instructors' Group of the Spanish Academy of Dermatology and Venereology (AEDV)

BACKGROUND

Skin problems are among the most frequent reasons for seeking medical attention in primary care. In recent years, as a result of the process of adapting medical curricula to the requirements of the European Higher Education Area, the amount of time students spend learning the concepts of dermatology has been reduced in many universities.

MATERIAL AND METHODS

In order to reach a consensus on core content for undergraduate education in dermatology, we sent a survey to the 57 members of the instructors' group of the Spanish Academy of Dermatology and Venereology (AEDV), asking their opinions on what objectives should be set for a dermatology course in Spain. A total of 131 previously selected objectives were listed. We then applied the Delphi method to achieve consensus on which ones the respondents considered important or very important (score≥4 on a Likert scale).

RESULTS

Nineteen responses (33%) were received. On the second round of the Delphi process, 68 objectives achieved average scores of at least 4. The respondents emphasized that graduates should understand the structure and functions of the skin and know about bacterial, viral, and fungal skin infections, the most common sexually transmitted diseases (STDs), and the 4 main inflammatory dermatoses. Students should also learn about common complaints, such as itching and bald patches; the management of dermatologic emergencies; purpura and erythema nodosum as signs of internal disease; and the prevention of STDs and skin cancer. During clinical clerkships students should acquire the communication skills they will need to interview patients, write up a patient's medical history, and refer the patient to a specialist.

CONCLUSIONS

The AEDV's group of instructors have defined their recommendations on the core content that medical faculties should adopt for the undergraduate subject of dermatology in Spain.

Genetic analysis and comparative virulence of infectious salmon anemia virus (ISAV) types HPR7a and HPR7b from recent field outbreaks in Chile

Background

Infectious salmon anemia (ISA) is a serious disease of marine farmed Atlantic salmon, Salmo salar L. caused by ISA virus (ISAV). ISAV genomic segments 5 and 6 encode surface glycoproteins hemagglutinin-esterase (HE) and F protein important for the pathogenicity of ISAV. In this study, we describe the genetic characteristics and relationship between ISAV-HPR7a and ISAV-HPR7b strains that caused the ISA outbreaks in Chile in 2013 and 2014, respectively, and the evolution of the ISAV clades since 2009 based on segment 5 and 6 sequences.

Methods

The study material included samples from six ISA cases in Chile. RNA was extracted from salmon tissues and ISAV isolated from cell culture; segments 5 and 6 were amplified by RT-PCR and compared by alignment with ISAV sequences from the GenBank database.

Results

ISAV-HPR7a and ISAV-HPR7b belong to the European Genotype I strains only found in Europe and Chile, and in both cases, show high similarity in segments 5 and 6 with identity between 95–96%. Our data confirm the hypothesis that the original virus was introduced to Chile in 1996. Compared to the 2007 ISAV-HPR7b isolate, the 2014 ISAV-HPR7b does not have an insertion in segment 5 and was associated with low mortality, which suggests that ISAV virulence was attenuated by the absence of the insertion in segment 5. In contrast, the highly virulent ISAV-HPR14 from April 2013 outbreak did not have the insertion in segment 5 either.

Conclusion

Variability in the ISAV virulence markers supports the quasispecies theory that multiple evolution forces are likely to shape ISAV genetic diversity. Our findings provide evidence of continuing evolution of ISAV in the Chilean aquaculture industry.

Electronic supplementary material

The online version of this article (doi:10.1186/s12985-014-0204-1) contains supplementary material, which is available to authorized users.

Infectious salmon anaemia virus (ISAV) in Chilean Atlantic salmon (Salmo salar) aquaculture: emergence of low pathogenic ISAV-HPR0 and re-emergence of virulent ISAV-HPR∆: HPR3 and HPR14

ABSTACT

Infectious salmon anaemia (ISA) is a serious disease of marine-farmed Atlantic salmon (Salmo salar) caused by ISA virus (ISAV), which belongs to the genus Isavirus, family Orthomyxoviridae. ISA is caused by virulent ISAV strains with deletions in a highly polymorphic region (HPR) of the hemagglutinin-esterase (HE) protein (designated virulent ISAV-HPR∆). This study shows the historic dynamics of ISAV-HPR∆ and ISAV-HPR0 in Chile, the genetic relationship among ISAV-HPR0 reported worldwide and between ISAV-HPR0 and ISAV-HPR∆ in Chile, and reports the 2013 ISA outbreak in Chile. The first ISA outbreak in Chile occurred from mid-June 2007 to 2010 and involved the virulent ISAV-HPR7b, which was then replaced by a low pathogenic ISAV-HPR0 variant. We analyzed this variant in 66 laboratory-confirmed ISAV-HPR0 cases in Chile in comparison to virulent ISAV-HPR∆ that caused two new ISA outbreaks in April 2013. Multiple alignment and phylogenetic analysis of HE sequences from all ISAV-HPR0 viruses allowed us to identify three genomic clusters, which correlated with three residue patterns of ISAV-HPR0 (360PST362, 360PAN362 and 360PAT362) in HPR. The virus responsible for the 2013 ISAV-HPR∆ cases in Chile belonged to ISAV-HPR3 and ISAV-HPR14, and in phylogenetic analyses, both clustered with the ISAV-HPR0 found in Chile. The ISAV-HPR14 had the ISAV-HPR0 residue pattern 360PAT362, which is the only type of ISAV-HPR0 variant found in Chile. This suggested to us that the 2013 ISAV-HPR∆ re-emerged from ISAV-HPR0 that is enzootic in Chilean salmon aquaculture and were not new introductions of virulent ISAV-HPR∆ to Chile. The clinical presentations and diagnostic evidence of the 2013 ISA cases indicated a mixed infection of ISAV with the ectoparasite Caligus rogercresseyi and the bacterium Piscirickettsia salmonis, which underscores the need for active ISAV surveillance in areas where ISAV-HPR0 is enzootic, to ensure early detection and control of new ISA outbreaks, as it is considered a risk factor. This is the first report of ISA linked directly to the presence of ISAV-HPR0, and provides strong evidence supporting the contention that ISAV-HPR0 shows a strong relationship to virulent ISAV-HPR∆ viruses and the possibility that it could mutate to virulent ISAV-HPR∆.

Video endoscopic inguinal lymphadenectomy: surgical and oncological results

INTRODUCTION

We evaluated the reproducibility of video endoscopic inguinal lymphadenectomy (VEIL) and we report our initial experience in the treatment of penile cancer with palpable inguinal lymph nodes.

MATERIAL AND METHODS

From July 2006 to November 2010 were conducted 33 VEIL in 20 patients as complementary treatment for penile cancer in two referral hospitals in Latin America. We analyzed the epidemiological and clinical characteristics of patients and surgical and oncologic outcomes.

RESULTS

Fifty-five percent of the patients included were clinical stage N0 and 45% were N +. Thirteen patients underwent bilateral VEIL and the remaining seven underwent VEIL unilateral and conventional open surgery in the contralateral limb. The average operative time for VEIL was 119 minutes and mean resected lymph nodes was 8 per lymphadenectomy. The overall complication rate was 33.2%. No patient had skin necrosis. The lymphatic complication rate was 27.2%. Of the 6 cases in which the saphenous vein was preserved (18.2%) there were no lymphatic complications (P=,2). The overall survival rate was 80% and cancer-specific survival was 90%. Mean follow-up was 20 months.

CONCLUSIONS

VEIL in the adjunctive treatment of penile cancer is safe, reproducible and may be an alternative to conventional lymphadenectomy. Patients with palpable lymphadenopathy also may benefit from this technique. Oncological results seem to be adequate however require longer follow-up to be confirmed.

Binding of Ru(NH3)5pz2+ to 4-sulfocalix[4]arene sodium salt. Effects of the host-guest interaction on electron transfer processes

The reactions [Ru(NH3)5pz]2++S2O8(2-) and [Ru(NH3)5pz]2++[Co(C2O4)3]3- have been studied in solutions of 4-sulfocalix[4]arene sodium salt. Results show a binding of the ruthenium complex to the calixarene with a 2:1 stoichiometry; that is, a ruthenium molecule binds to two calixarene molecules. This stoichiometry changes when NaCl is added to the medium. Thus, a mixture of 1:1 and 2:1 adducts is found in the presence of 0.1 mol dm(-3) NaCl and only 1:1 adducts when the salt concentration is increased up to 0.3 mol dm(-3). Results show that the binding of the ruthenium complex to the calixarene is due to electrostatic and nonelectrostatic interactions. Kinetic data are interpreted by using the pseudophase model and taking into account the stoichiometry of the ruthenium binding to calixarene. The presence of a supporting electrolyte in the medium produces ion pair formation which exerts an influence on the kinetic rate constants.

Arg113His mutation of vanishing white matter is not present in multiple sclerosis

Vanishing white matter (VWM) is a childhood leukoencephalopathy with central hypomyelination, white matter rarefaction, and cystic degeneration. Adult onset, variable phenotype, and high frequency characterize Arg113His mutation caused by G338A polymorphism associated with VWM. A patient with trauma-associated onset, and clinical features compatible with multiple sclerosis (MS), was homozygous for G338A mutation of eukaryotic translation initiation factor (eIF2B5). The authors checked a cohort of 101 MS patients, including 19 with head/neck trauma-associated onset, and failed to find the mutation, described above, in MS chromosomes. Our report does not exclude the presence in MS chromosomes of other mutations in the eIF2B gene family. Multiple Sclerosis 2007; 13: 424-427. http://msj.sagepub.com

Rapid assessment of drug consumption at Santa Cruz de la Sierra, Bolivia

The present paper describes a rapid assessment carried out in 1996 at Santa Cruz de la Sierra, Bolivia, with a view to defining the sociocultural groups at risk and gaining insight, through the comments of those interviewed, into their perceptions of the phenomenon of drug abuse, their reasons for abusing drugs, the drugs most frequently abused and the psychological and social factors involved when they enter, remain in and finally leave drug-abusing circles. By using qualitative methodology and techniques it was possible to gain access to the typical world inhabited by the interviewees, and thus to characterize the subjects of the study in the light of their closest social reference points (family, peer group, education and work). Among the conclusions of the study are the following: drug abuse is a complex and dynamic phenomenon that has occurred throughout the society of Santa Cruz, fostered by cultural and economic factors; there is a need for society, and especially the Government, to devise a specific, focused and diversified range of services, both in prevention and in rehabilitation, with integration and participation being key features of such initiatives; and the mechanisms for controlling the production of drugs and drug trafficking need to be strengthened.

Honeybee flight muscle phosphoglucose isomerase: matching enzyme capacities to flux requirements at a near-equilibrium reaction

In honeybee flight muscle, there are close matches between physiological flux rates and the maximal activities (Vmax; determined using crude homogenates) of key enzymes catalyzing non-equilibrium reactions in carbohydrate oxidation. In contrast, phosphoglucose isomerase (PGI), which catalyzes a reaction believed to be close to equilibrium, occurs at Vmax values greatly in excess of glycolytic flux rates. In this study, we measure the Vmax of flight muscle PGI, the kinetic parameters of the purified enzyme, the apparent equilibrium constants for the reaction and the tissue concentrations of substrate and product. Using the Haldane equation, we estimate that the forward flux capacity (Vf) for PGI required to achieve physiological glycolytic flux rates is between 800 and 1070 units ml-1 cell water, approximately 45&shy;60 % of the empirically measured Vmax of 1770 units ml-1 cell water at optimal pH (8.0) and low ionic strength (no added KCl). When measured at physiological pH (7.0) and ionic strength (120 mmol l-1 KCl) with saturating levels of substrate, PGI activity is 1130 units ml-1 cell water, a value close to the calculated Vf. These results reveal a very close match between predicted and measured PGI flux capacities, and support the concept of an economical design of muscle metabolism in systems working at very high metabolic rates.

Estradiol effect on rate of proliferation of rat carotid segments: effect of gender and tamoxifen

Using organ culture of carotid artery segments from sexually mature male and female rats, we examined the effect of estradiol 17 beta on proliferation. The index of cell proliferation was [3H]thymidine uptake. Estradiol 17 beta (0.18-0.36 microM) inhibited the uptake of thymidine in a concentration-dependent manner (p < 0.05). Estradiol 17 beta inhibited [3H]thymidine uptake only in the absence of the weak estrogen receptor agonist phenol red and in carotid artery segments from sexually mature female (p < 0.01) but not male rats. Tamoxifen (0.1 and 1 microM), a partial agonist of estrogen receptors, significantly inhibited thymidine uptake (p < 0.01). However, preincubation of the segments with tamoxifen (0.1 and 1.0 microM) for 4 h before the exposure to estradiol, blocked estradiol 17 beta-induced inhibition of thymidine uptake (p < 0.05 and p < 0.01 for 0.1 and 1.0 microM, respectively). The cyclooxygenase inhibitor indomethacin (5 microM) did not affect either the basal [3H]thymidine uptake or the estradiol 17 beta-induced inhibition of that uptake. This latter finding suggests that prostacyclin or prostaglandin E2 does not mediate the inhibitory response to estradiol 17 beta. The results of these experiments suggest that estradiol 17 beta-induced inhibition of proliferation of rat carotid artery segments is mediated through activation of estrogen receptors.

Hamsters with coronary vasospasm are at increased risk from stress

Results of earlier experiments suggested that hamsters with inherited heart disease were at a higher risk of succumbing to stress during the vasospastic, lesion-forming period of their lives rather than later when the process of congestive heart failure had begun. To test this hypothesis, we stressed cardiomyopathic hamsters (CMH) whose ages differed by about 3 months; the younger of the two groups of stressed hamsters was in the vasospastic phase of the disease. The stressor was cold immobilization in which stressor intensity was manipulated using two durations of cold exposure. Log rank survival curves revealed no difference in mortality with the more intense stressor. However, significantly fewer of the older hamsters succumbed to the less intense stressor (46% as compared with 85% of the younger CMHs). Examination of the hearts in the experiment where mortality rate was the same for both groups revealed evidence of cardiac dilatation, indicative of heart failure, only in the older hamsters following stress. Since the younger hamsters did not show these changes and since they, but not the older animals, have coronary microvascular spasm and an increased susceptibility to stress, it would appear that the process of coronary vasospasm should be viewed as an independent and additional risk factor in determining the consequences of stress. Because of the effects of stress in the younger cardiomyopathic hamster, we believe that a neural link--which can be activated by stress--may be involved in the pathogenetic process of coronary vasospasm.

Childhood sudden death secondary to accidental aspiration of black pepper

The case history is presented of a 4-year-old boy, with a history of pica, who aspirated table pepper with subsequent respiratory arrest, severe anoxia, and death. We believe this to be the first case reported in the literature of fatal accidental aspiration of pepper.

Echo-free renal masses on ultrasound: the stethoscope as an adjunct to their diagnosis

A patient with an intrarenal arteriovenous malformation is described. Ultrasound suggested this to be a renal cyst but auscultation revealed a loud bruit and, on the basis of this, arteriography rather than cyst puncture was carried out.

Multiple primary tumors in association with prostatic cancer

One hundred forty-six patients with clinically nonmetastatic carcinoma of the prostate were treated at Columbia-Presbyterian Medical Center from 1964 through 1976. Of these 146 patients, 24 (16.4%) had developed at least one additional primary cancer. This review contrasts the 122 patients who had a single primary prostate cancer only with the 24 patients who had additional primary carcinomas with respect to age, racial distribution, clinical stage, and prostate cancer histology including Gleason's score, patterns of failure of prostate cancer, and survival data. Local failure and distant failure were less in the multiple primary group. Patients with high Gleason's scores appear to be at greater risk for second primaries. Five-year observed survival (by actuarial life table method) for the single prostate primary group was 76.5%, and 5-year observed survival of the prostate multiple primary group where prostate cancer appeared first was 71%.

Amiodarone-induced pulmonary fibrosis in hamsters

Amiodarone, a cardiac antiarrhythmic agent, has been associated with the development of interstitial pulmonary fibrosis in patients receiving prolonged therapy with the drug. To further assess the toxic effects of amiodarone on lung tissue, Syrian hamsters were given a single intratracheal insufflation of the agent and evaluated for histologic evidence of lung injury. Control animals received intratracheal insufflations of the vehicle in which amiodarone was dissolved. After an initial, transient alveolitis in both experimental and control animals, the amiodarone-treated lungs developed increased interstitial thickening due to fibrinous exudates, alveolar epithelial hyperplasia, inflammatory cell infiltrates, and marked deposition of collagen manifested on trichrome staining. Controls, in contrast, showed nearly complete resolution of the initial alveolitis. An unusual feature of the amiodarone-induced lung injury was reemergence of the alveolitis between 5 and 14 days, which included a marked influx of eosinophils into the lung. Although the precise mechanism of the lung injury is not known, the persistence of the acute inflammatory cells as well as the presence of eosinophils suggests a hypersensitivity-type reaction. Furthermore, the progression of lung injury to fibrosis after a single insult with the drug suggests that mere discontinuation of amiodarone therapy in humans may not reverse the disease process, but that corticosteroid therapy may also be required. Amiodarone appears to be a useful agent to induce diffuse fibrotic reactions in the lung that morphologically resemble idiopathic pulmonary fibrosis in humans.

Clinical survey of the forms, number and localization of retinal tears in cases of relapses and recurrences in retinal detachment

This study deals with the clinical observations of the different forms and shapes of retinal tears, their number and localizations in cases of relapses and recurrences in retinal detachement surgery. Two groups of patients were considered, the first belongs to our own centre and the second to referred patient operated in other hospitals. 45.1% of both groups account for relapses. We find 7.35% of undetected retinal breaks. The greater number of tears are mainly distributed in the temporal quandrants. The most common shapes of breaks are the punched-out hole, fingernail-tip-like tears, small and medium horseshoe tears, oval and 'pebbled'-like (cluster of microholes) holes. Approximately 25% of the breaks were seen in areas where thermotherapy had not been applied and 15% of them were found beside most probably overtreated areas.