Primary preputial reconstruction following surgical excision of cutaneous mast cell tumours without penile amputation in eight dogs.

CASE HISTORY: Medical records from a single referral hospital (Davies Veterinary Specialists, Hitchin, UK) were reviewed to identify dogs (n = 8) with preputial cutaneous mast cell tumours (CMCT) that underwent surgical excision and primary preputial reconstruction, preserving the penis and urethra, after clients declined alternatives such as penile amputation and urethrostomy, from June 2017-June 2022. CLINICAL FINDINGS: Tumours had a median diameter of 21.5 (min 15, max 30) mm, were located cranioventrally (3/8), caudoventrally (1/8), laterally (2/8) and dorsally (2/8) relative to the prepuce and were diagnosed as CMCT based on cytology. No dogs had hepatic or splenic metastasis on cytology but inguinal lymph node metastasis was identified in 3/4 dogs sampled. TREATMENT AND OUTCOME: The owners of all dogs had declined penile amputation and scrotal urethrostomy. The CMCT were excised and primary reconstruction of the prepuce performed. Surgical lateral margins of 10, 20 or 30 mm were used and the deep margin excised the inner preputial lamina or underlying muscular fascia. The deep margin for caudoventral CMCT involved excision of the underlying SC adipose tissue. Preputial advancement was performed in 3/8 dogs to achieve adequate penile coverage. Histopathology confirmed all CMCT were Kiupel low grade, Patnaik grade II with complete margins in 6/8 dogs but identified metastasis only in one inguinal lymph node from one dog. Two dogs encountered minor complications (infection and a minor dehiscence) and one dog had a major complication (infection with major dehiscence). Median follow-up duration was 125 weeks, excluding one dog with 4 weeks of follow-up. None of the dogs experienced local recurrence or died of mast cell disease during the available follow-up period. CLINICAL RELEVANCE:  This clinical study evaluated a surgical alternative to penile amputation and advanced reconstructive techniques for Kuipel low/Patnaik grade II preputial CMCT when these procedures were declined by owners. Surgical excision of preputial CMCT with lateral margins of 10, 20 or 30 mm with primary preputial reconstruction is achievable with low morbidity and a good outcome when penile amputation and scrotal urethrostomy is not an option.

Extreme environments: microbiology leading to specialized metabolites.

The prevalence of multidrug-resistant microbial pathogens due to the continued misuse and overuse of antibiotics in agriculture and medicine is raising the prospect of a return to the preantibiotic days of medicine at the time of diminishing numbers of drug leads. The good news is that an increased understanding of the nature and extent of microbial diversity in natural habitats coupled with the application of new technologies in microbiology and chemistry is opening up new strategies in the search for new specialized products with therapeutic properties. This review explores the premise that harsh environmental conditions in extreme biomes, notably in deserts, permafrost soils and deep-sea sediments select for micro-organisms, especially actinobacteria, cyanobacteria and fungi, with the potential to synthesize new druggable molecules. There is evidence over the past decade that micro-organisms adapted to life in extreme habitats are a rich source of new specialized metabolites. Extreme habitats by their very nature tend to be fragile hence there is a need to conserve those known to be hot-spots of novel gifted micro-organisms needed to drive drug discovery campaigns and innovative biotechnology. This review also provides an overview of microbial-derived molecules and their biological activities focusing on the period from 2010 until 2018, over this time 186 novel structures were isolated from 129 representatives of microbial taxa recovered from extreme habitats.

Pseudonocardia hispaniensis sp. nov., a novel actinomycete isolated from industrial wastewater activated sludge.

A novel actinomycete, designated PA3(T), was isolated from an oil refinery wastewater treatment plant, located in Palos de la Frontera, Huelva, Spain, and characterized taxonomically by using a polyphasic approach. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate formed a distinct subclade in the Pseudonocardia tree together with Pseudonocardia asaccharolytica DSM 44247(T). The chemotaxonomic properties of the isolate, for example, the presence of MK-8 (H(4)) as the predominant menaquinone and iso-C(16:0) as the major fatty acid, are consistent with its classification in the genus Pseudonocardia. DNA:DNA pairing experiments between the isolate and the type strain of P. asaccharolytica DSM 44247(T) showed that they belonged to separate genomic species. The two strains were readily distinguished using a combination of phenotypic properties. Consequently, it is proposed that isolate PA3(T) represents a novel species for which the name Pseudonocardia hispaniensis sp. nov. is proposed. The type strain is PA3(T) (= CCM 8391(T) = CECT 8030(T)).

Phylogenetic study of the species within the family Streptomycetaceae.

Species of the genus Streptomyces, which constitute the vast majority of taxa within the family Streptomycetaceae, are a predominant component of the microbial population in soils throughout the world and have been the subject of extensive isolation and screening efforts over the years because they are a major source of commercially and medically important secondary metabolites. Taxonomic characterization of Streptomyces strains has been a challenge due to the large number of described species, greater than any other microbial genus, resulting from academic and industrial activities. The methods used for characterization have evolved through several phases over the years from those based largely on morphological observations, to subsequent classifications based on numerical taxonomic analyses of standardized sets of phenotypic characters and, most recently, to the use of molecular phylogenetic analyses of gene sequences. The present phylogenetic study examines almost all described species (615 taxa) within the family Streptomycetaceae based on 16S rRNA gene sequences and illustrates the species diversity within this family, which is observed to contain 130 statistically supported clades, as well as many unsupported and single member clusters. Many of the observed clades are consistent with earlier morphological and numerical taxonomic studies, but it is apparent that insufficient variation is present in the 16S rRNA gene sequence within the species of this family to permit bootstrap-supported resolution of relationships between many of the individual clusters.

Reassessment of the systematics of the suborder Pseudonocardineae: transfer of the genera within the family Actinosynnemataceae Labeda and Kroppenstedt 2000 emend. Zhi et al. 2009 into an emended family Pseudonocardiaceae Embley et al. 1989 emend. Zhi et al. 2009.

The taxonomic status of the families Actinosynnemataceae and Pseudonocardiaceae was assessed based on 16S rRNA gene sequence data available for the 151 taxa with validly published names, as well as chemotaxonomic and morphological properties available from the literature. 16S rRNA gene sequences for the type strains of all taxa within the suborder Pseudonocardineae were subjected to phylogenetic analyses using different algorithms in arb and phylip. The description of many new genera and species within the suborder Pseudonocardineae since the family Actinosynnemataceae was proposed in 2000 has resulted in a markedly different distribution of chemotaxonomic markers within the suborder from that observed at that time. For instance, it is noted that species of the genera Actinokineospora and Allokutzneria contain arabinose in whole-cell hydrolysates, which is not observed in the other genera within the Actinosynnemataceae, and that there are many genera within the family Pseudonocardiaceae as currently described that do not contain arabinose. Phylogenetic analyses of 16S rRNA gene sequences for all taxa within the suborder do not provide any statistical support for the family Actinosynnemataceae, nor are signature nucleotides found that support its continued differentiation from the family Pseudonocardiaceae. The description of the family Pseudonocardiaceae is therefore emended to include the genera previously classified within the family Actinosynnemataceae and the description of the suborder Pseudonocardineae is also emended to reflect this reclassification.

Treatment outcomes of laryngectomy compared to non-surgical management of T3 laryngeal carcinomas: a 10-year multicentre audit of 179 patients in the northeast of England.

OBJECTIVE: Wide-ranging outcomes have been reported for surgical and non-surgical management of T3 laryngeal carcinomas. This study compared the outcomes of T3 tumours treated with laryngectomy or (chemo)radiotherapy in the northeast of England. METHODS: The outcomes of T3 laryngeal carcinoma treatment at three centres (2007-2016) were retrospectively analysed using descriptive statistics and survival curves. RESULTS: Of 179 T3 laryngeal carcinomas, 68 were treated with laryngectomies, 57 with chemoradiotherapy and 32 with radiotherapy. There was no significant five-year survival difference between treatment with laryngectomy (34.1 per cent) and chemoradiotherapy (48.6 per cent) (p = 0.184). The five-year overall survival rate for radiotherapy (12.5 per cent) was significantly inferior compared to laryngectomy and chemoradiotherapy (p = 0.003 and p < 0.001, respectively). The recurrence rates were 22.1 per cent for laryngectomy, 17.5 per cent for chemoradiotherapy and 50 per cent for radiotherapy. There were significant differences in recurrence rates when laryngectomy (p = 0.005) and chemoradiotherapy (p = 0.001) were compared to radiotherapy. CONCLUSION: Laryngectomy and chemoradiotherapy had significantly higher five-year overall survival and lower recurrence rates compared with radiotherapy alone. Laryngectomy should be considered in patients unsuitable for chemotherapy, as it may convey a significant survival advantage over radiotherapy alone.

Relation between facial fractures and socioeconomic deprivation in the north east of England.

Patients with a low socioeconomic status suffer disproportionately from trauma, and have a high incidence of mandibular fractures. To explore how deprivation affects the incidence of facial fractures in the north east of England, we reviewed 1096 patients who were admitted to the oral and maxillofacial surgical (OMFS) unit at Sunderland Royal Hospital for treatment of a facial fracture between December 2013 and December 2017. Levels of socioeconomic deprivation, which were obtained from postcodes and the UK Government Open Data Communities database, were compared with a random sample of deprivation data from the catchment area of our hospital. Patients with nasal and mandibular fractures were more likely to be socioeconomically deprived than those in the catchment area of our hospital (p = 0.006 and p < 0.001, respectively), but this was not the case in those with malar/maxillary or orbital floor fractures (p = 0.184 and p = 0.641, respectively). The incidence of fractures that were caused by assault was not associated with increased socioeconomic deprivation (p = 0.241). Patients of low socioeconomic status were more likely to have been under the influence of a substance when the injury occurred (p = 0.014). There is a strong association between socioeconomic deprivation and facial fractures. OMFS departments should therefore be as accessible as possible to patients from more disadvantaged backgrounds, given their greater risk of injury.

Search and discovery strategies for biotechnology: the paradigm shift.

Profound changes are occurring in the strategies that biotechnology-based industries are deploying in the search for exploitable biology and to discover new products and develop new or improved processes. The advances that have been made in the past decade in areas such as combinatorial chemistry, combinatorial biosynthesis, metabolic pathway engineering, gene shuffling, and directed evolution of proteins have caused some companies to consider withdrawing from natural product screening. In this review we examine the paradigm shift from traditional biology to bioinformatics that is revolutionizing exploitable biology. We conclude that the reinvigorated means of detecting novel organisms, novel chemical structures, and novel biocatalytic activities will ensure that natural products will continue to be a primary resource for biotechnology. The paradigm shift has been driven by a convergence of complementary technologies, exemplified by DNA sequencing and amplification, genome sequencing and annotation, proteome analysis, and phenotypic inventorying, resulting in the establishment of huge databases that can be mined in order to generate useful knowledge such as the identity and characterization of organisms and the identity of biotechnology targets. Concurrently there have been major advances in understanding the extent of microbial diversity, how uncultured organisms might be grown, and how expression of the metabolic potential of microorganisms can be maximized. The integration of information from complementary databases presents a significant challenge. Such integration should facilitate answers to complex questions involving sequence, biochemical, physiological, taxonomic, and ecological information of the sort posed in exploitable biology. The paradigm shift which we discuss is not absolute in the sense that it will replace established microbiology; rather, it reinforces our view that innovative microbiology is essential for releasing the potential of microbial diversity for biotechnology penetration throughout industry. Various of these issues are considered with reference to deep-sea microbiology and biotechnology.

Estimation of brain network ictogenicity predicts outcome from epilepsy surgery.

Surgery is a valuable option for pharmacologically intractable epilepsy. However, significant post-operative improvements are not always attained. This is due in part to our incomplete understanding of the seizure generating (ictogenic) capabilities of brain networks. Here we introduce an in silico, model-based framework to study the effects of surgery within ictogenic brain networks. We find that factors conventionally determining the region of tissue to resect, such as the location of focal brain lesions or the presence of epileptiform rhythms, do not necessarily predict the best resection strategy. We validate our framework by analysing electrocorticogram (ECoG) recordings from patients who have undergone epilepsy surgery. We find that when post-operative outcome is good, model predictions for optimal strategies align better with the actual surgery undertaken than when post-operative outcome is poor. Crucially, this allows the prediction of optimal surgical strategies and the provision of quantitative prognoses for patients undergoing epilepsy surgery.

Comparison between Ki-67 index and mitotic index for predicting outcome in canine mast cell tumours.

OBJECTIVES: To assess correlation between Ki67 index and mitotic index and determine which more accurately predicts survival in canine mast cell tumours. METHODS: Retrospective analysis of cases from three UK referral hospitals. Correlation between Ki67 index and mitotic index was assessed and survival analysis performed. RESULTS: A total of 162 dogs were included: 57 dogs died with 37 due to mast cell tumour. Correlation between Ki67 index and mitotic index was moderate, while the agreement was poor. A high Ki67 index was considered sensitive (86 · 5%) at predicting mast cell tumour-related death, but poorly specific (57 · 9%). Mitotic index(>5) was poorly sensitive (32 · 4%), but highly specific (96%). A mitotic index of ê2 had a 75 · 7% sensitivity and an 80 · 0% specificity. Ki67 index showed a statistically significant survival difference within the mitotic index <2 (P = 0 · 009) group. Ki67 index did not predict survival rate in tumours with mitotic index of ê2. CLINICAL RELEVANCE: Correlation between Ki67 and mitotic index is moderate. High mitotic index accurately predicted death, but many dogs with low mitotic index also died. Low Ki67 accurately predicted survival, but high Ki67 should not be considered a poor prognostic indicator. A three-tier mitotic index assessment may more accurately predict death due to mast cell tumour.

Numerical classification and identification of Streptomyces species--a review.

Evidence is presented to show that numerical taxonomy is of proven value both for the circumscription and identification of Streptomyces species. In addition, 252 representatives of numerically defined species and species-groups of this taxon were examined for 273 unit characters and the resultant data analysed using conventional statistics. Clustering was only marginally affected by the proximity coefficients used or by test error, estimated at 3.37%. The numerical classification obtained confirmed and extended the results of previous taxometric surveys, notably by showing that the Streptomyces albidoflavus species-group encompassed taxospecies corresponding to S. albidoflavus, Streptomyces anulatus and Streptomyces halstedii. Rapid enzyme tests based upon the fluorophores, 7-amino-4-methylcoumarin and 4-methylumbelliferone, provide useful data for streptomycete systematics. It can be concluded that the genus Streptomyces is currently well circumscribed and underspeciated.

Pyrolysis mass spectrometry as a method for the classification, identification and selection of actinomycetes.

Pilot experiments were designed to determine the potential of Curie-point pyrolysis mass spectrometry (PyMS) in the classification, identification and typing of industrially significant actinomycetes, and for the detection of target and novel actinomycetes needed for pharmacological screening programmes. The results indicate that the method is of value for the separation of actinomycetes at and below the species level, in the detection and circumscription of novel actinomycetes, and for the detection of identical and duplicated strains. There is also evidence that the pyrolysis system will permit the identification of target actinomycetes directly from selective isolation plates. PyMS is one of the methods that should be used to generate polyphasic taxonomies of actinomycete genera.

Identification of some clinically significant actinomycetes.

Early recognition of infections caused by actinomycetes tend to be highly dependent on at least a tentative diagnosis derived from microbiological tests, since the clinical symptoms can be difficult to interpret. Reliable identification of clinically significant actinomycetes depends upon the application of taxonomic techniques that are not yet widely used in clinical laboratories. The value of rapid enzyme, chemical and molecular fingerprinting techniques is exemplified by their application to the identification of representatives of clinically significant actinomycete taxa.

Distribution of oxoacyl synthase homology sequences within Streptomyces DNA.

A genomic DNA sequence of Streptomyces strain ISP 5485 was cloned, sequenced and compared with corresponding information from nuclei acid data banks. The DNA sequence was unique, but showed homology to DNA coding for the condensing enzyme, 2-oxoacyl synthase, of the deoxyerythronolide B synthase complex (DEBS) from Saccharopolyspora erythraea NRRL 2338. A subfragment of the sequenced DNA was used to construct a gene-specific probe that formed part of the putative 2-oxoacyl synthase gene. The PCR-amplified and labelled probe was used in hybridization experiments involving 33 streptomycete strains that produced different classes of antibiotics. The probe showed widespread homology with DNA considered to be part of analogous genes within genomes of different polyketide producers. The implications of the probe homology to bacterial chromosomal DNA are discussed.

A phylogenetic analysis of the genus Catellatospora based on 16S ribosomal DNA sequences, including transfer of Catellatospora matsumotoense to the genus Micromonospora as Micromonospora matsumotoense comb. nov.

Phylogenetic studies based on the 16S ribosomal gene sequences showed that members of the genus Catellatospora revealed phylogenetic heterogeneity within the family Micromonosporaceae as well as a heterogeneous menaquinone composition. Among them, Catellatospora matsumotoense was closely related to members of the genus Micromonospora, indicating that this organism should be excluded from the genus Catellatospora. On the basis of classical taxonomic characteristics and phylogenetic evidence, Catellatospora matsumotoense is proposed to be transferred to the genus Micromonospora as M. matsumotoense comb. nov.

Artificial neural network analysis of pyrolysis mass spectrometric data in the identification of Streptomyces strains.

Sixteen representatives of three morphologically distinct groups of streptomycetes were recovered from soil using selective isolation procedures. Duplicated batches of the test strains were examined by Curie-point pyrolysis mass spectrometry and the first data set used for conventional multivariate statistical analyses and as a training set for an artificial neural network. The second set of data was used for 'operational fingerprinting' and for testing the artificial neural network. All of the test strains were correctly identified using the artificial neural network whereas only fifteen of the sixteen strains were assigned to the correct group using the conventional operational fingerprinting procedure. Artificial neural network analysis of pyrolysis mass spectrometric data provides a rapid, cost-effective and reproducible way of identifying and typing large numbers of microorganisms.

Rapid identification of streptomycetes by artificial neural network analysis of pyrolysis mass spectra.

An artificial neural network was trained to distinguish between three putatively novel species of Streptomyces using normalised, scaled prolysis mass spectra from three representative strains of each of the taxa, each sampled in triplicate. Once trained, the artificial neural network was challenged with spectral data from the original organisms, the 'training set', from additional members of the putative novel taxa and from over a hundred strains representing six other actinomycete genera. All of the streptomycetes were correctly identified but many of the other actinomycetes were mis-identified. A modified network topology was developed to recognise the mass spectral patterns of the non-streptomycete strains. The resultant neural network correctly identified the streptomycetes, whereas all of the remaining actinomycetes were recognised as unknown organisms. The improved artificial neural network provides a rapid, reliable and cost-effective method of identifying members of the three target streptomycete taxa.

Epidemiological typing of coagulase-negative staphylococci by pyrolysis mass spectrometry.

Pyrolysis mass spectrometry (PMS) was evaluated for the epidemiological typing of coagulase-negative staphylococci (CNS) in situations in which it was necessary to distinguish between repeated isolation of the same strain from a single patient (genuine infection) and coincidental isolation of unrelated strains (contamination). Thirteen CNS isolates were examined, consisting of five pairs, each pair isolated from a single patient, and three unrelated strains. PMS analysis gave results equivalent to a conventional typing system comprising antibiogram, biotype and plasmid profile analysis. Both methods facilitate differentiation between genuine infection with CNS and the isolation of contaminants. The speed, reproducibility, versatility and relatively low cost of PMS suggest that it may be a valuable new technique for the epidemiological typing of CNS in routine clinical settings.

Pyrolysis-mass spectrometry (Py-MS) for the rapid epidemiological typing of clinically significant bacterial pathogens.

Fresh clinical isolates of Salmonella spp. and Streptococcus pyogenes were analysed by pyrolysis-mass spectrometry (Py-MS). The results formed the basis of mathematically derived characterizations of individual strains and these were compared with the results of phage typing for the salmonellas and M protein typing for the streptococci. Py-MS was shown to be a rapid and reproducible method for inter-strain comparisons, giving evidence of identity and non-identity between strains that agreed well with the results of conventional tests. Py-MS has potential value as a rapid, relatively inexpensive and highly discriminatory method of epidemiological analysis in bacterial disease.

Taxonomic position of "Pseudomonas oxalaticus" strain ox14T (DSM 1105T) (Khambata and Bhat, 1953) and its description in the genus Ralstonia as Ralstonia oxalatica comb. nov.

"Pseudomonas oxalaticus" strain Ox1T (= DSM 1105T), which was described as an oxalate-decomposing bacterium, was reinvestigated to clarify its taxonomic position. 16S ribosomal DNA sequence comparisons demonstrated that this species is phylogenetically related to the species of the genus Ralstonia. and represents a new species. The result of the DNA-DNA hybridization value was supported in this placement. Strain Ox1T is closely related to Ralstonia eutropha with a less than 60% DNA-DNA hybridization value. The new name Ralstonia oxalatica comb. nov. is proposed to strain Ox1T, on the basis of these results and previously published data for the G+C content of the genomic DNA and the phenotypic characters.