Near-infrared fluorescent image-guided lymph node dissection compared with locoregional lymphadenectomies in dogs with mast cell tumours.

OBJECTIVES: Near-infrared fluorescent imaging has been described for intraoperative mapping of the draining lymph nodes in human cancer and canine oral tumours. The aim of this study was to retrospectively describe the results of lymphadenectomies in dogs with mast cell tumours treated either by standard unguided locoregional lymph node dissection or near-infrared fluorescent image-guided lymph node dissection. METHODS: Medical records between 2012 and 2020 were reviewed for dogs that were presented for surgical resection of mast cell tumours with concurrent lymphadenectomy either with (near-infrared fluorescent image-guided lymph node dissection) or without near-infrared fluorescence image guidance (lymph node dissection). The number and location of lymph nodes planned for surgical dissection and actually dissected nodes, presence of metastases and perioperative complications were recorded. RESULTS: Thirty-five patients underwent near-infrared fluorescent image-guided lymph node dissection, and 43 lymph node dissections. The number of nodes preoperatively planned for resection were 70 and 68, respectively. Fifty-eight of those (83%) were identified during near-infrared fluorescent image-guided lymph node dissection procedures, compared with 50 (74%) during lymph node dissection. near-infrared fluorescent image-guided lymph node dissection resulted in resection of additional fluorescent nodes not corresponding to locoregional nodes in 15 of 35 dogs. Using near-infrared fluorescent image-guided lymph node dissection, we identified at least one metastatic node in 68% of dogs (24 of 35) compared with 33% (14 of 43) when lymph node dissection was used without imaging. No complications related to near-infrared fluorescent imaging were reported. CLINICAL SIGNIFICANCE: The present study suggests that near-infrared imaging is a promising technique for intraoperative detection of the draining lymph nodes in dogs with mast cell tumours. Further validation of the technique is required to assess if near-infrared fluorescent imaging can detect the true sentinel lymph node.

Aligning tumor mutational burden (TMB) quantification across diagnostic platforms: phase II of the Friends of Cancer Research TMB Harmonization Project.

BACKGROUND: Tumor mutational burden (TMB) measurements aid in identifying patients who are likely to benefit from immunotherapy; however, there is empirical variability across panel assays and factors contributing to this variability have not been comprehensively investigated. Identifying sources of variability can help facilitate comparability across different panel assays, which may aid in broader adoption of panel assays and development of clinical applications. MATERIALS AND METHODS: Twenty-nine tumor samples and 10 human-derived cell lines were processed and distributed to 16 laboratories; each used their own bioinformatics pipelines to calculate TMB and compare to whole exome results. Additionally, theoretical positive percent agreement (PPA) and negative percent agreement (NPA) of TMB were estimated. The impact of filtering pathogenic and germline variants on TMB estimates was assessed. Calibration curves specific to each panel assay were developed to facilitate translation of panel TMB values to whole exome sequencing (WES) TMB values. RESULTS: Panel sizes >667 Kb are necessary to maintain adequate PPA and NPA for calling TMB high versus TMB low across the range of cut-offs used in practice. Failure to filter out pathogenic variants when estimating panel TMB resulted in overestimating TMB relative to WES for all assays. Filtering out potential germline variants at >0% population minor allele frequency resulted in the strongest correlation to WES TMB. Application of a calibration approach derived from The Cancer Genome Atlas data, tailored to each panel assay, reduced the spread of panel TMB values around the WES TMB as reflected in lower root mean squared error (RMSE) for 26/29 (90%) of the clinical samples. CONCLUSIONS: Estimation of TMB varies across different panels, with panel size, gene content, and bioinformatics pipelines contributing to empirical variability. Statistical calibration can achieve more consistent results across panels and allows for comparison of TMB values across various panel assays. To promote reproducibility and comparability across assays, a software tool was developed and made publicly available.

The role of sentinel lymph node mapping in small animal veterinary medicine: A comparison with current approaches in human medicine.

The relevance of regional lymph node (LN) assessment to quantify the metastatic spread of cancer is well recognized in veterinary oncology. Evaluation of LNs is critical for tumour staging. However, sampling the correct LN may not be possible without sentinel lymph node (SLN) mapping. Methods for diagnostic imaging and intraoperative detection of SLNs are well established in human medicine, in particular, the combination of lymphoscintigraphy and intraoperative application of blue dyes. Nevertheless, alternative imaging techniques are available and have gained increasing interest. Successful implementation of these techniques in dogs have been reported in both clinical and experimental studies. This review aims to provide an overview of SLN mapping techniques in human and veterinary medicine.

Persistent STAT5 activation in myeloid neoplasms recruits p53 into gene regulation.

STAT (Signal Transducer and Activator of Transcription) transcription factors are constitutively activated in most hematopoietic cancers. We previously identified a target gene, LPP/miR-28 (LIM domain containing preferred translocation partner in lipoma), induced by constitutive activation of STAT5, but not by transient cytokine-activated STAT5. miR-28 exerts negative effects on thrombopoietin receptor signaling and platelet formation. Here, we demonstrate that, in transformed hematopoietic cells, STAT5 and p53 must be synergistically bound to chromatin for induction of LPP/miR-28 transcription. Genome-wide association studies show that both STAT5 and p53 are co-localized on the chromatin at 463 genomic positions in proximal promoters. Chromatin binding of p53 is dependent on persistent STAT5 activation at these proximal promoters. The transcriptional activity of selected promoters bound by STAT5 and p53 was significantly changed upon STAT5 or p53 inhibition. Abnormal expression of several STAT5-p53 target genes (LEP, ATP5J, GTF2A2, VEGFC, NPY1R and NPY5R) is frequently detected in platelets of myeloproliferative neoplasm (MPN) patients, but not in platelets from healthy controls. In conclusion, persistently active STAT5 can recruit normal p53, like in the case of MPN cells, but also p53 mutants, such as p53 M133K in human erythroleukemia cells, leading to pathologic gene expression that differs from canonical STAT5 or p53 transcriptional programs.

Ex vivo expansion of normal and chronic myeloid leukemic stem cells without functional alteration using a NUP98HOXA10homeodomain fusion gene.

HOX genes have been implicated as regulators of normal and leukemic stem cell functionality, but the extent to which these activities are linked is poorly understood. Previous studies revealed that transduction of primitive mouse hematopoietic cells with a NUP98HOXA10homeodomain (NA10HD) fusion gene enables a subsequent rapid and marked expansion in vitro of hematopoietic stem cell numbers without causing their transformation or deregulated expansion in vivo. To determine whether forced expression of NA10HD in primitive human cells would have a similar effect, we compared the number of long-term culture-initiating cells (LTC-ICs) present in cultures of lenti-NA10HD versus control virus-transduced CD34(+) cells originally isolated from human cord blood and chronic phase (CP) chronic myeloid leukemia (CML) patients. We found that NA10HD greatly increases outputs of both normal and Ph(+)/BCR-ABL(+) LTC-ICs, and this effect is particularly pronounced in cultures containing growth factor-producing feeders. Interestingly, NA10HD did not affect the initial cell cycle kinetics of the transduced cells nor their subsequent differentiation. Moreover, immunodeficient mice repopulated with NA10HD-transduced CP-CML cells for more than 8 months showed no evidence of altered behavior. Thus, NA10HD provides a novel tool to enhance both normal and CP-CML stem cell expansion in vitro, without apparently altering other properties.

Genetic variations in androgen metabolism genes and associations with prostate cancer in South African men.

Background. In South Africa white men have the highest incidence of prostate cancer (PCa), coloured (mixed ancestry) men have an intermediate incidence, and low incidences are reported for black and Asian men. It has been suggested that ethnic differences in incidence and mortality of PCa are related to genetic variations in genes that regulate androgen metabolism. We investigated the role of genetic variants in the androgen metabolism genes and the probability of developing PCa in South African coloured and white men. Methods. Genotype and allele counts and frequencies of single nucleotide polymorphisms (SNPs) in CYP3A5, CYP3A4 and CYP3A43 were assessed in coloured men (160 case individuals, 146 control individuals) and white men (121 case individuals, 141 control individuals). Results. A genetic association indicating an increased probability of developing PCa was observed with the G allele of the SNP rs2740574 in CYP3A4 in coloured men, the A allele of rs776746 (CYP3A5) and the G allele of rs2740574 (CYP3A4) in white men, and the G allele of rs2740574 and the C allele of rs501275 (CYP3A43) in the combined ethnic groups analysis. In addition, we identified allele combinations (termed haplotypes) with significantly higher frequencies in the PCa case individuals than in the control individuals. Conclusions. The findings support the role of variants in genes that regulate androgen metabolism and the probability of developing PCa. The study paves the way to identify other genetic associations in South African men, and to establish genetic profiles that could be used to determine disease progression and prognosis.

Cardiovascular and pupillary autonomic nervous dysfunction in patients with rheumatoid arthritis - a cross-sectional and longitudinal study.

OBJECTIVES: Patients with inflammatory diseases often demonstrate autonomic nervous dysfunction. This study was initiated to investigate cardiovascular (CAD) or pupillary autonomic dysfunction (PAD) in patients with rheumatoid arthritis (RA). METHODS: Between 1997 and 1998, 33 RA patients were examined for characteristics, and parameters of CAD and PAD. In a longitudinal part of this study, thirty patients have been re-evaluated 8.3 +/- 0.1 yr later (response rate = 91%). RESULTS: A total of 18 patients (60%) demonstrated either CAD or PAD. The prevalence of CAD was 6/30 (20%) and the prevalence of PAD was 15/30 (50%). Of all cardiovascular tests, the Ewing test demonstrated the worst results (13/30 patients were below the 5th percentile). Similar as in other diseases, several RA patients demonstrated autonomic nervous hyperreflexia with values above the 95 th percentile (relative variation coefficient: 7/30; respiratory sinus arrhythmia measure: 12/30; Valsalva measure: 1/30; Ewing measure: 0/30; latency time of pupillary light reflex: 5/30; maximal pupillary area: 0/30). During the 8-year observation period, 4/30 RA patients died. Non-survivors as compared to survivors had increased heart rate variation in the respiratory arrhythmia test (p= 0.038, hyperreflexia) but largely decreased heart rate variation in the Ewing test (p= 0.009, hyporeflexia). Non-survivors as compared to survivors demonstrated more frequent pupillary autonomic dysfunction (100% vs. 42%, p= 0.035). CONCLUSION: This study demonstrates that CAD and PAD were frequent in patients with RA. Patients with a poor test result in the Ewing test and PAD might have an increased risk of death. This study in RA patients demonstrates similar results as in patients with diabetes mellitus.

Intravitreal preservative-free triamcinolone acetonide for the treatment of macular oedema.

PURPOSE: To report the use of commercially available preservative-free intravitreal triamcinolone acetonide for the treatment of macular oedema due to retinal vascular diseases. DESIGN: Retrospective interventional case series. METHODS: Charts of eyes that received 4 mg preservative-free intravitreal triamcinolone acetonide for the treatment of persistent macular oedema due to retinal vascular diseases were reviewed. Patients were included if they had a follow-up of at least 3 months. Visual acuity, intraocular pressure, presence of an anterior chamber reaction, and mean macular thickness on optical coherence tomography (OCT) were recorded. RESULTS: A total of 10 eyes of 10 patients were identified. Visual acuity improved by a mean of 1.1 Snellen lines at 1 month and 1.3 lines at 3 months. Macular thickness on OCT decreased by a mean of 183.5 microm at 1 month (P<0.0001). Intraocular pressure increased from a mean of 13.5 mmHg at baseline to 15.3 at 1 month, and 14.5 at 3 months. Only the 1-month change in intraocular pressure was statistically significant (P=0.0274). There were no cases of endophthalmitis, anterior chamber reaction, or retinal detachment. CONCLUSION: In this small retrospective, noncomparative series, commercially available preservative-free intravitreal triamcinolone acetonide had no adverse outcomes. Macular oedema was noted to decrease following treatment.

Photodynamic therapy for maculopathy due to radiation retinopathy.

BACKGROUND/AIMS: To describe the clinical outcomes of four eyes with macular oedema due to radiation retinopathy treated with verteporfin photodynamic therapy (PDT). METHODS: Interventional Case Series. Four charts of four patients who underwent PDT for macular oedema due to radiation retinopathy were reviewed. Snellen visual acuities, clinical examination and fundus photographs were performed before and after PDT. Main outcome measures were visual acuity, clinical examination before and after PDT. RESULTS: All four eyes had a marked reduction in hard exudates. Three of four eyes had an improvement in vision following the PDT. CONCLUSION: PDT may have a role in the treatment of macular oedema due to radiation retinopathy.

Problems with prostate specific antigen screening for prostate cancer in the primary healthcare setting in South Africa.

OBJECTIVES: To assess the feasibility of detecting early-stage prostate cancer in the primary healthcare setting, and to investigate whether there is a higher incidence of prostate cancer in Black African men. PATIENTS AND METHODS: The study was a collaboration with registrars in the authors' institutions and primary healthcare centres serving mainly a Black African or mixed ancestry (Coloured) population in the semi-urban Cape Town metropolitan area of South Africa. Men aged 50-70 years attending the clinics were counselled about prostate cancer and invited to have a digital rectal examination (DRE), serum prostate-specific antigen (PSA) assay and transrectal ultrasonography-guided sextant prostate biopsy if the DRE was clinically suspicious of malignancy or the serum PSA was > or = 4.0 ng/mL. An American Urological Association Symptom Index (AUA-SI) was obtained, and urine analysed using dipsticks. RESULTS: From May 2000 to November 2001, 660 men were assessed (mean age 59.4 years, range 30-82); 60.6% were Black African, 37.3% mixed (Coloured), 1.8% White (Caucasian) and 0.2% Asian (Indian). The mean (range) AUA-SI was 5.98 (0-35) in the whole group; the DRE was recorded as clinically suspicious of malignancy in 3.2%. The mean PSA was 20.39 (0.04-10 000) ng/mL in the whole group, but when two outliers (1865 and 10 000 ng/mL) were disregarded, it was 2.4 ng/mL. In Black patients the mean PSA was 31.8 (0.04-10 000) ng/mL, and without the outliers, 2.1 ng/mL; in Coloured patients it was 2.94 (0.05-50) ng/mL. The PSA was > or = 4.0 ng/mL in 9.6% of the whole group, in 7.8% of Black and in 13% of Coloured patients. Prostate biopsies were taken in 21 patients (3.2% of the whole group and a third of those with a PSA of > or = 4.0 ng/mL); in Black patients, biopsies were taken in 1.5% and 19.4%, respectively, and in Coloured patients in 6.1% and 46.9%, respectively. The prostate biopsy showed cancer in 43% of the whole group, in a third of Black and in 47% of Coloured patients; prostate cancer was detected in 1.4%, 0.5% and 2.8%, respectively. CONCLUSIONS: That prostate biopsies were obtained in only 19% of Black and in only 47% of Coloured men with a serum PSA of > or = 4.0 ng/mL is of concern. This indicates that there is a significant problem in getting men with an elevated serum PSA level to undergo a prostate biopsy in the primary healthcare setting in South Africa.

Novel resorcin[4]arenes as potassium-selective ion-channel and transporter mimics.

A series of novel resorcin-[4]arenes with extended pi systems have been synthesised and developed as potassium-selective transporters. Resorcin[4]arenes that feature crown ether moieties function as efficient carriers of K+ across bulk liquid membranes showing enhanced selectivity over the other alkali metal ions relative to a model system (benzo[15]crown-5). Incorporation of functionalities suitable for pore formation, in addition to an extra annulus of aromatic residues, gives molecules which have remarkable ion-channel-mimicking behaviour in a biological lipid bilayer with outstanding K+/Na+ selectivity.

Ion pair cooperative binding of potassium salts by new rhenium(I) bipyridine crown ether receptors.

The new rhenium(I) bipyridine crown ether receptors 1-4 have been prepared and their ion pair recognition properties examined. The crystal structure of [1.KCl](2).2H(2)O demonstrates that potassium is coordinated by benzo-18-crown-6 and chloride is hydrogen bonded to the amide groups. Receptor 3 extracts solid KCl and KOAc into chloroform via ion pair complexation. NMR and emission titration studies with receptors 1-4 and KCl/KOAc show that cobound potassium enhances anion binding strength by electrostatic and conformational effects. Significant cooperative interactions are observed between the anion and cation sites for host 4 in CH(3)CN. This molecule coordinates potassium to form a 1:1 intramolecular sandwich complex, which preorganizes the host for acetate binding.

The binding of difunctional neutral guest molecules by novel bis(tripyrrolyl) cryptands.

Bis(tripyrrolyl) cryptands are prepared via a [2 + 3] Schiff base condensation of formyltripyrrolyls with diamines; an ethyl-spaced hexapyrrole cryptand is shown to bind strongly ethane-1,2-diamine and ethane-1,2-diol in chloroform solution.

Molecular recognition of anions by synthetic receptors.

Over the past year, several significant developments have been made in the field of anion binding. The fundamental principles of molecular recognition are increasingly being better understood, and of particular interest are reports of several synthetic anion receptors able to perform their task in complex natural media. Additionally, macroscopic devices such as anion specific electrodes and membranes based on a molecular recognition approach are now being made.

Spontaneous regression and successful laser prophylaxis in progressive outer retinal necrosis syndrome.

PURPOSE: To describe a case of progressive outer retinal necrosis syndrome that regressed spontaneously after discontinuation of all systemic antiviral medications with macular sparing after prophylactic laser photocoagulation of the posterior pole. METHODS: Prophylactic laser photocoagulation surrounding the posterior pole was performed in an attempt to spare the macula from detachment in a patient with progressive outer retinal necrosis. RESULTS: Progressive outer retinal necrosis regressed spontaneously without systemic antiviral medications. The posterior pole within the area of photocoagulation remained attached. CONCLUSIONS: Prophylactic laser treatment surrounding the posterior pole rather than peripheral retina may allow more time for formation of firm chorioretinal adhesions and protect the macula from detachment.

Cenani-Lenz syndrome in father and daughter.

We present a father and daughter with typical clinical and radiological features of Cenani-Lenz syndrome. Cenani-Lenz syndrome has been delineated as a type of complete syndactyly resembling the spoon hand seen in Apert syndrome, with as important additional feature, the fusion of metacarpals and disorganization of the phalanges. Based on the observation of the syndrome in at least two affected siblings born to normal parents and the consanguinity in one family autosomal recessive inheritance was proposed. The findings in the present family could indicate that Cenani-Lenz syndrome may be genetically heterogeneous. Another possible explanation could be that the occurrence in affected siblings born to normal parents could be explained by gonadal mosaicism for an autosomal dominant gene.

Polymerase chain reaction in the diagnosis of urinary tract tuberculosis.

The polymerase chain reaction (PCR) is a technique that can be used to amplify a specific DNA genomic sequence, whereby the presence of an extremely small number of bacteria can be detected. The high sensitivity of PCR is particularly useful in paucibacillary situations such as non-pulmonary tuberculosis (TB). The aims of the present study were to establish a PCR assay for the rapid detection of Mycobacterium tuberculosis (MTb) in urine, to compare the sensitivity of PCR with routine culture technique (Bactec) and to determine the optimal type of urine specimen for PCR detection of MTb. In the first phase of the study, a total of 92 urine specimens were collected from 83 patients with suspected urinary tract TB. Two urine specimens in 2 patients were positive for TB by both PCR and Bactec, while 90 specimens from 81 patients were negative by both methods. Inhibition of PCR was present in nine urine specimens (10%). In the second phase of the study, a further seven patients were selected for intensive investigation to determine the optimal urine sampling for PCR detection of MTb. The conclusions of the study are that PCR can provide much faster confirmation of urinary TB (within 24-48 h) than Bactec urine culture (which may take several weeks). About 10% of urine specimens could not be evaluated by PCR due to the presence of inhibitory substances of unknown nature. MTb organisms were found to be excreted intermittently in the urine of infected patients, and single specimens were more likely to be false negative than a 24-h sample. The best method appeared to be the concentration of a large volume of urine, for instance 11 concentrated to 2 ml.