Skin infection by Mycobacterium farcinogenes-senegalense group in an immunocompetent patient: a case report

Background

Mycobacterium farcinogenes–senegalense group mostly cause bovine farcy, which rarely infect human beings. We reported one case of cutaneous Mycobacterium farcinogenes–senegalense group infection in an immunocompetent victim.

Case presentation

A 66-year-old Taiwanese woman with hypertension developed tender nodules on her left dorsal foot for 2 months. Tissue culture identified Mycobacterium farcinogenes–senegalense group. The lesion was treated successfully with clarithromycin and sulfamethoxazole/trimethoprim, followed by surgical excision.

Conclusions

Mycobacterium farcinogenes–senegalense group infection should be considered as a potential pathogen of skin infection in immunocompetent patients.

Uremic Pruritus: From Diagnosis to Treatment

Uremic pruritus, or chronic kidney disease-associated pruritus, is common, bothersome, and sometimes debilitating in patients with chronic kidney disease or end-stage renal disease. Due to its variable clinical manifestations, the diagnosis of uremic pruritus requires exquisite evaluation. Excluding itch resulting from other dermatological causes as well as other systemic conditions is essential for a proper diagnosis. The pathophysiology of uremic pruritus remains uncertain. Hypotheses including toxin deposition, immune system dysregulation, peripheral neuropathy, and opioid imbalance are supposed. This review summarizes the way to accurately diagnose uremic pruritus and describes the latest treatment options.

Impaired Wnt/beta-catenin and protein patched homolog 1 signaling in extraocular sebaceous carcinoma: A clinical and histopathological study

Sebaceous carcinoma (SC) is a rare malignant neoplasm with sebaceous differentiation. SC is classified into eyelid and extraocular SC clinically. Most studies have focused on the eyelid SC in terms of pathogenesis, treatment, and prognosis. In skin, Wnt/beta-catenin and hedgehog signaling are two major pathways in sebaceous differentiation. We aimed to characterize the clinical and histopathological features of extraocular SC and to measure the expression of beta-catenin, lymphoid enhancer-binding factor 1 (LEF1), sonic hedgehog (Shh), and protein patched homolog 1 (PTCH) in extraocular SC. Ten cases of extraocular SC were identified from 2007 to 2020. The clinical features, microscopic findings, and prognosis were analyzed. Immunohistochemical stain for beta-catenin, LEF1, Shh, and PTCH were performed in extraocular SC and other benign sebaceous tumors including sebaceous hyperplasia, sebaceous adenoma, and sebaceoma. The male:female ratio was 4:6. The median onset age was 73.5 years (range, 43-88). Seven patients out of 10 were diagnosed after 60 years. Most extraocular SC were located on the head and neck with indurated plaque. Two patients had concurrent internal cancers and three patients showed lymph node metastasis at time of presentation. Five-year overall-survival was 40%. Beta-catenin was expressed membranously in all sebaceous hyperplasia, but was expressed variably in extraocular SC (1/5). While LEF1 was unequivocally expressed in normal hair follicles, LEF1 expression was absent in all extraocular SC and benign sebaceous tumors. Regarding the sonic hedgehog signaling, Shh and PTCH were all expressed in the cytoplasm of sebaceous hyperplasia, sebaceous adenoma, and sebaceoma. In contrast, PTCH was absent in all cases of extraocular SC and only 50% of the extraocular SC expressed cytoplasmic Shh. To conclude, extraocular SC commonly affects facial skin in the elderly. Inactivated Wnt/beta-catenin and aberrant hedgehog pathway may contribute to the carcinogenesis of extraocular SC. Further studies may be required to elucidate the causative mechanism of these pathways in extraocular SC.

Primary scarring alopecia: A retrospective study of 89 patients in Taiwan

Primary scarring alopecia (PSA) is caused by irreversible damage to the hair epithelial stem cells that reside in hair follicles. There is limited published work regarding PSA amongst the Asian population. The aim of this study was to evaluate the clinical features and to characterize the subtypes of PSA in southern Taiwan. In this retrospective case series, we reviewed 89 patients with pathology-confirmed PSA. The data was collected from National Cheng Kung University Hospital between 1988 through 2016. The clinical and histological data were reviewed, and the patients were characterized into different subtypes of PSA based on the clinical features and histological findings. We noted seven different subtypes of PSA. The most common type was dissecting cellulitis (DC) (30.3%), followed by lichen planopilaris (LPP) (23.5%), central centrifugal cicatricial alopecia (CCCA) (12.4%) and acne keloidalis nuchae (AKN) (12.4%). The other subtypes include folliculitis decalvans (FD), discoid lupus erythematosus (DLE) and pseudopelade of Brocq (PPB). Interestingly, FD, DC and AKN were more common in males, while CCCA, LPP, DLE and PPB had a female predominance. The mean age of patients with DLE, DC and AKN were younger, while patients with CCCA, LPP, PPB and FD tend to be older. The pattern of hair loss was more likely to be unifocal-ragged border in CCCA and DLE, multifocal-interconnected in LPP and FD, and multifocal-separated in DC. The pathogenesis of PSA may be influenced by sex, age and genetic background. It is important to identify the hair loss pattern to differentiate the subtypes of PSA.

Fluoroscopic Frameless Computer-Assisted Navigation for Transsphenoidal Surgery: A Clinical Assessment of Accuracy in Spatial Position and Trajectory

OBJECTIVE

Fluoroscopic navigation technique in transsphenoidal surgery on the one hand provides multi-planar (antero-posterior and lateral views) navigation while on the other hand it does not need any preoperative preparation. To assess the clinical accuracy of the above technique in the transsphenoidal surgery, we performed this study.

METHODS

5 patients undergoing transsphenoidal surgery were assessed. Fluoroscopic images were compared with C-arm X-ray images for difference in spatial position and trajectory.

RESULTS

26 sets of data were collected for analysis. Mean pointer tip difference was 0.6 mm. The 95 % confidence interval was 1.3 mm. Mean trajectory difference was 1.2 degree. The 95 % confidence interval was 2.7 degree.

CONCLUSION

With a good clinical accuracy, fluoroscopic navigation offers a distinct advantage to replace the traditional fluoroscopic approach for transsphenoidal surgery for its low X-ray exposure and multi-planar (antero-posterior and lateral views) navigation.

Quality of life in long-term survivors of intensive care

INTRODUCTION

Traditionally, outcome from intensive care has focused on mortality. The cost of intensive care and the limited resources devoted to patients who have a poor prognosis also raises questions about the utilisation of such resources. There is increasing pressure for outcome evaluation of intensive care to incorporate assessment of long-term survival and the quality of life in survivors. The principal objectives of this article were to examine current methods of assessing quality of life measures in critically ill patients surviving intensive care and to determine the quality of life of these survivors.

METHODS

Direct and computerised search of published research articles.

RESULTS

Measurement of quality of life after intensive care is not common practice. There is a lack of consensus concerning appropriate measuring instruments to be used and how best to interpret results. Despite the availability of general outcome tools and disease specific instruments, there is a paucity of studies in the literature which include assessments of quality of life following intensive care unit (ICU) care. Generic health indices suggest that the quality of life in ICU survivors is acceptable though in certain sub-groups, e.g. adult respiratory distress syndrome and sepsis, quality of life may be moderately impaired. ICU survivors appear to suffer less disability than chronic physical disease patients.

CONCLUSIONS

Assessment of outcome after intensive care should include health related quality of life measurements. A unifying framework is required to enhance communication between clinicians, administrators and investigators of quality of life research and also to enable more rational and effective decision making at the bedside. Patients who survive intensive care appear to enjoy a reasonable standard of quality of life. While their health status may not be as good, subjectively patients find this acceptable.

"Paper-clip" type triple helix formation by 5'-d-(TC)3Ta(CT)3Cb(AG)3 (a and b = 0-4) as a function of loop size with and without the pseudoisocytosine base in the Hoogsteen strand

The formation of a DNA "paper-clip" type triple helix (triplex) with a common sequence 5'-d-(TC)(3)T(a)()(CT)(3)C(b)()(AG)(3) (a and b = 0-4) was studied by UV thermal melting experiments and CD spectra. These DNA oligomers form triplexes and duplexes under slightly acidic and neutral conditions, respectively. The stability of the formed triplexes (at pH 4.5) or duplexes (at pH 7.0 or 8.0) does not vary significantly with the size of the loops (a and b = 1-4). At pH 6.0, the triplex stability is, however, a function of a and b. It is also interesting to note that the oligomer 5'-d-(TC)(3)(CT)(3)(AG)(3) (a and b = 0) forms a stable triplex at pH 4.5 with a slightly lower T(m) value, due to dissociation of a base triad at one end and a distorted base triad at the other, observed by (1)H NMR. Thus, we have here a model system, 5'-d-(TC)(3)T(a)(CT)(3)C(b)(AG)(3), that could form a triplex effectively with (a and b = 1-4) and without (a and b = 0) loops under acidic conditions. In addition, the triplex formation of oligomers with replacement of one, two, or three 2'-deoxycytidine in the Hoogsteen strand by either 2'-deoxypseudoisocytidine (D) or 2'-O-methylpseudoisocytidine (M) was also studied in the sequence 5'-d-(TX)(3)T(2)(CT)(3)C(2)(AG)(3) (where X is C, D, or M). Both CD spectra and UV melting results showed that only D3 [(TX)(3) = (TD)(3)] and M3 [(TX)(3) = (TM)(3)] were able to form the paper-clip structure under both neutral and acidic conditions. This is because the N(3)H of a pseudoisocytosine base can serve as a proton donor without protonation. We hereby proved that the 2'-deoxypseudoisocytidine, similar to 2'-O-methylpseudoisocytidine, could replace 2'-deoxycytidine in the Hoogsteen strand to provide triplex formation at neutral pH.

Developing a quality of life measure for Chinese patients with diabetes

The objective of this study was to develop a Chinese version of the Diabetes Quality of Life measure (DQOL), appropriate for elderly Chinese immigrants with Type 2 diabetes, and evaluate its reliability and validity through psychometric testing. Using an established diabetes quality of life measure, we employed focus groups to modify the instrument to be appropriate for an elderly Chinese population. The revised version was forward translated and back translated by four individuals independently. A review committee consensus determined the final version, which was pre-tested on five lay people to assess the equivalence of meaning. Elderly Chinese patients with Type 2 diabetes (n = 70) attending either an endocrinology or family practice clinic near Toronto were recruited to complete the Chinese version of the DQOL. Reliability of the instrument was assessed by evaluating internal consistency, item-internal consistency and test-retest reliability. Divergent validity was assessed to show that the instrument could detect worsening quality of life associated with diabetic complications. The Chinese version of the DQOL consists of 42 items and three scales including satisfaction, impact and diabetes-related worry. The DQOL and its three scales had high degrees of internal consistency (Cronbach's alpha = 0.76-0.92) and excellent test-retest reliability (Pearson correlation = 0.94-0.99). All items had high correlation with their hypothesized scale with the exception of three items. Divergent validity of the instrument was demonstrated. This study provides evidence for the reliability and validity of this Chinese version of the DQOL measure for an elderly Chinese population with Type 2 diabetes. This instrument may be used in future studies to better understand the quality of life of the Chinese population with diabetes.

Perioperative management of intra-partum seizure

A young nulliparous woman previously diagnosed with pregnancy-induced hypertension suffered a seizure during active first stage labour. Pre-seizure blood pressure was borderline high but she did not fulfill other criteria for preeclampsia. She underwent emergency caesarean section for presumed eclampsia. Postoperatively, she deteriorated neurologically. CT scan showed an intracranial haemorrhage requiring neurosurgical intervention. The similarities of presentation of a primary cerebrovascular event and eclampsia following an intra-partum seizure made the differential diagnosis difficult.

Relative Resistance of Adipocytes from Massively Obese Persons to Dedifferentiation

Previous studies on the etiology of obesity have revealed that human adipocytes have the ability to revert or dedifferentiate in culture to a morphology and replicative capacity similar to that of adipocyte precursors. To characterize some of the events of this process, we isolated adipocytes from the greater omentum of 61 morbidly obese and ten normal weight individuals with collagenase, and cultured them for 0, 4, and 7 days. In both lean and obese patients, sn-glycerol-3-phosphate dehydrogenase specific activity decreased significantly after days 4 and 7 compared to day 0. Dedifferentiation was also monitored by phase-contrast microscopy, which revealed that adipocytes from the lean had lost appreciable lipid and had assumed an elongated contour more rapidly than those from the obese. Reversion was also corroborated by reverse transcription-polymerase chain reaction, which indicated a decrease in the expression of sn-glycerol-3-phosphate dehydrogenase mRNA, and an increase in actin and glyceraidehyde-3-phosphate dehydrogenase mRNA over the 7 days. Thus, this work has described some biochemical and molecular genetic characteristics of dedifferentiation. The relative resistance of adipocytes from morbidly obese patients to revert in culture may reflect the inordinately high propensity of fat cells in massively obese persons to preserve the differentiated, triacylglycerol-overfilled state.

Development of a second-generation fiber-optic on-line image verification system

PURPOSE

We have previously reported the development of a fiber-optic fluoroscopic system for on-line imaging on radiation therapy machines with beam-stops because of space limitation. While the images were adequate for clinical purposes in most cases, an undesirable grid artifact existed and distracted visualization. The resolving power of the system, limited by the 1.6 mm x 1.6 mm dimension of the input fibers, appeared insufficient in some cases. This work identifies solutions to reduce grid artifact and to improve the resolution of the system.

METHODS AND MATERIALS

In the clinical system, it was found that the scanning mechanism of the newvicon camera was deflected differently at various gantry positions because of the different orientation of the earth's magnetic field. The small image misregistration produced grid artifact during image normalization, particularly near boundaries of the fiber bundles. One approach taken to reduce magnetic field effects was to shield the camera with mu-metal. Alternatively, a charged-coupled-device camera was used instead of the newvicon camera. As for improving spatial resolution, fibers with smaller input dimension were used. A 20 cm x 20 cm high resolution fiber-optic prototype consisting of 250 x 250 fibers, each with an input dimension of 0.8 mm x 0.8 mm was constructed. Its performance was tested using several phantoms studies.

RESULTS

Both shielding the newvicon camera with mu-metal or replacing it with a charge-coupled-device camera reduced grid artifact. However, optimal shielding could not be made for our clinical system because of the space limitation of its housing. High contrast resolution was improved, the 30% value of the modulation transfer function occurred at 0.3 linepairs per mm for the clinical system and at 0.7 linepairs per mm for the high-resolution prototype. However, because of the larger degree of transmission non-uniformity of the prototype, it was less effective using the current setup in detecting low contrast objects.

CONCLUSIONS

The results are encouraging and demonstrate successful reduction of grid artifact and improvement of high contrast spatial resolution using the proposed methods. The less effective low contrast detection was related to reduced light collection efficiency due to use of prototype fibers whose productions were not closely monitored. The findings are being considered in our construction of a second generation clinical fiber-optic on-line image verification system.

A method to analyze 2-dimensional daily radiotherapy portal images from an on-line fiber-optic imaging system

On-line radiotherapy imaging systems allow convenient treatment verification and generate a wealth of data. Quantitative analysis of data will provide important information about the nature of treatment variations. Using an inhouse fiber-optic imaging system to acquire daily portal images for five patients, we have developed a method to analyze the cumulative positional variation of blocks in the 2-dimensional images. For each beam arrangement used to treat a particular patient, a reference portal image was established. All other images for that patient were registered with respect to the anatomical landmarks visible on the reference image. Two-dimensional frequency distributions describing the overlap of the blocks during the course of treatment were then calculated and superimposed on the reference image. Results of the analysis show positional and quantitative information about the daily variation in block placement, and appeared to be site-dependent. Long term verification studies using on-line imaging systems will be important in the understanding of treatment uncertainties.

On-line radiotherapy imaging with an array of fiber-optic image reducers

In the optical approach for on-line radiotherapy imaging, a large metal sheet-fluorescent screen combination is used to convert the radiation intensity distribution into a visible light image. Data are then captured via a mirror with a camera located out of the beam. Although usable portal images can be acquired, presence of the large mirror renders the system impractical in many treatment geometries. We have overcome this limitation by replacing the mirror with an array of 16 by 16 bundles of plastic fiber-optic image reducers. Each bundle, in turn, is made up of 16 by 16 individual optical fibers. The total of 256 by 256 fibers spans an input area of 40 cm by 40 cm with each individual fiber viewing an area of 1.6 mm by 1.6 mm. Within a height of 12 cm, each fiber is reduced to an area of 0.1 mm by 0.1 mm. The reduced portal image is then turned and "piped" to a final 3.0 cm by 3.0 cm output area. For data acquisition and digitization, the fiber output is directly coupled to the sensor of a TV camera interfaced to a small computer via a 512 by 512 frame grabber. In this initial evaluation, the imaging system has been characterized in terms of its line spread function, noise and resistance to radiation damage. Adequate phantom and patient images are presented.