Syringocystadenocarcinoma papilliferum: a systematic review of clinical characteristics, reappraisal of associations, diagnostic pitfalls and management challenges.

Syringocystadenocarcinoma papilliferum (SCACP) is a rare and aggressive malignant adnexal tumor originating from apocrine or pluripotent appendageal glands, often associated with a preceding syringocystadenoma papilliferum (SCAP) or nevus sebaceus (NS). This systematic review rigorously examines SCACP through an analysis of 78 cases documented between 1980 and 2024. The study aims to provide a comprehensive review of the clinical manifestations, diagnosis, treatment modalities, and outcomes associated with SCACP, while also reappraising its associations, particularly with NS. SCACP predominantly affects older adults, with an average age of 66.3 years and a slight male predominance, commonly presenting as ulcerated nodules or plaques on the scalp. This review highlights the aggressive nature of SCACP, evidenced by significant rates of metastasis and recurrence. Treatment is primarily surgical, with Mohs micrographic surgery offering potential benefits in terms of margin control and cosmetic outcomes. The association of SCACP with NS is critically evaluated, suggesting a complex etiopathogenesis and underscoring the importance of recognizing this association for timely diagnosis and management. Our review also briefly discusses potential pitfalls faced by clinicians in the diagnosis of SCACP. Our findings emphasize the need for standardized treatment protocols and further research into targeted therapies to improve patient outcomes in SCACP.

A systematic review of basal cell carcinoma on the scrotum-reviewing presentation and identifying challenges in management.

Since the scrotum is rarely exposed to sunlight, basal cell carcinoma (BCC) development in this area is an uncommon occurrence. As result, there is a scarcity of research covering this particular presentation, which poses a diagnostic and therapeutic challenge for clinicians. The objective of this systematic review is to provide a thorough overview of scrotal BCC, including a summary of its clinical characteristics, and microscopic subtypes. It also seeks to discuss the many techniques used in the management of this uncommon clinical presentation. Utilizing data from 1957 to October 2023, a systematic review of PubMed and Wiley Online Library was conducted to identify all cases of scrotal BCC with various presentations and managements. A total of 73 patients were included. The median patient age was 65.9 years (range 42 to 87). All studies were either case reports or case series. Our review shows that treatment with Mohs micrographic surgery (MMS), leads to a superior patient outcome based on anecdotal evidence in select cases. To deepen our understanding of Mohs surgery's efficacy in treating scrotal BCC, it is imperative to conduct more robust research in the form of randomized clinical trials.

The RGD (Arg-Gly-Asp) is a potential cell-binding motif of UNC-52/PERLECAN.

UNC-52/perlecan is a basement membrane (BM) proteoglycan playing an essential role in the muscle cell attachment of C. elegans. The UNC-52 protein contains two RGD (Arg-Gly-Asp) motifs in domains III and IV, a well-characterized tripeptide known for binding to mammalian ß integrin. To investigate the role of the RGD motif in UNC-52/perlecan, we created two mutations in the 2021RGD2023 motif: one mutation changed the RGD to an RGE, and the other deleted the RGD motif. The RGE2023 caused defective actin filaments and aberrant localization of PAT-3 ß integrin and TLN-1/talin. Additionally, the in-frame deletion of RGD2023 resulted in a paralyzed and arrested at two-fold embryonic stages (Pat) phenotype, which is the identical phenotype of the pat-3 ß integrin null allele. These results indicate that RGD2023 is a potential ligand for cell binding and is essential for development and survival. Furthermore, our analysis reveals that the RGD of an invertebrate BM molecule is a potential cell-binding motif, suggesting that the function of the RGD motif is conserved among species.

Deletion of the RGD motif in LON-2/glypican is associated with morphological abnormalities.

The lon-2 gene in Caenorhabditis elegans encodes a heparan sulfate proteoglycan family glypican that negatively regulates the BMP signaling pathway responsible for controlling body length. LON-2 contains multiple functional domains, including an RGD (Arg-Gly-Asp) motif at amino acid number from 348 to 350. A novel mutant allele of lon-2 was investigated in this study. In this mutant allele, lon-2(kq348ΔRGD), the RGD motif at position 348 was deleted. Another pre-existing mutant allele, lon-2(e678), contains a ~9kb deletion and lacks most of the genomic coding sequence. The lon-2(e678) line was used as a reference allele. The novel mutant line was significantly shorter than wild-type animals, suggesting that removal of the RGD motif in LON-2 may improve its ability to inhibit BMP signaling.

Interaction of petroleum-relevant organosulfur compounds with TiO2(110).

The interaction of two sets of structurally related molecules, thiophenol/thioanisole, and thiophene/tetrahydrothiophene, with vacuum-annealed and ion-bombarded TiO(2)(110) surfaces has been studied using a combination of temperature-programmed reaction spectroscopy (TPRS) and X-ray photoelectron spectroscopy (XPS). All thioethers studied were observed to adsorb and desorb from both surfaces without producing reaction products, while thiophenol, the only species studied containing a S-H bond, reacted with both surfaces. Approximately 25% of surface bound thiophenol decomposed over the vacuum-annealed surface. On the bombarded surface, thiophenol both decomposed into surface-bound C(x)H(y)/S fragments, and reacted to form benzene, which desorbed from the surface at 400 K. We propose that phenylthiolate formation on the bombarded surface leads to the observed production of benzene. These results highlight the importance of defects in the reactivity of titania, and lay the foundation for the study of larger, refractory sulfur compounds present in fuel.

Altered PET functional brain responses in cognitively intact elderly persons at risk for Alzheimer disease (carriers of the epsilon4 allele).

OBJECTIVE: Few previous studies have investigated the association between APOE genotype and brain activation during performance of cognitive tasks in healthy middle-aged and elderly subjects, and the results have been mixed. The authors investigated APOE-mediated differential brain activation in a group of healthy elderly subjects. METHODS: Using H215O positron emission tomography (PET), they imaged 32 healthy subjects (26 non-epsilon4 carriers and 6 epsilon4 carriers) performing a serial shape-recognition memory task under two conditions: Simple Demand (SD), in which one shape was presented in each study trial, and Titrated Demand (TD), in which study list length was adjusted so that each subject recognized words at approximately 75% accuracy. Multiple-regression analyses were performed, with the "activation" difference (TD-SD PET counts) as the dependent variable and the APOE genotype (presence versus absence of the epsilon4 allele) as the independent variable. RESULTS: Compared with non-carriers, epsilon4 carriers exhibited significantly decreased TD-SD activation differences in the left superior temporal, right superior frontal, left postcental, left precuneus, and posterior cingulate gyrus because epsilon4 carriers (versus non-carriers) showed increased activation during the SD and decreased activation during the TD condition. CONCLUSION: Patterns of brain activation during a nonverbal memory task differed as a function of APOE genotype and, therefore, of genetic risk for Alzheimer disease (AD). Differences in activation were not a reflection of task difficulty, but indicate memory-related altered cognitive processing. Brain regions with decreased activation in the epsilon4 subjects may result from subclinical incipient AD pathology and/or APOE-related neurophysiologic heterogeneity.

Covariance PET patterns in early Alzheimer's disease and subjects with cognitive impairment but no dementia: utility in group discrimination and correlations with functional performance.

Although multivariate analytic techniques might identify diagnostic patterns that are not captured by univariate methods, they have rarely been used to study the neural correlates of Alzheimer's disease (AD) or cognitive impairment. Nonquantitative H2(15)O PET scans were acquired during rest in 17 probable AD subjects selected for mild severity [mean-modified Mini Mental Status Examination (mMMS) 46/57; SD 5.1], 16 control subjects (mMMS 54; SD 2.5) and 23 subjects with minimal to mild cognitive impairment but no dementia (mMMS 53; SD 2.8). Expert clinical reading had low success in discriminating AD and controls. There were no significant mean flow differences among groups in traditional univariate SPM Noxel-wise analyses or region of interest (ROI) analyses. A covariance pattern was identified whose mean expression was significantly higher in the AD as compared to controls (P = 0.03; sensitivity 76-94%; specificity 63-81%). Sites of increased concomitant flow included insula, cuneus, pulvinar, lingual, fusiform, superior occipital and parahippocampal gyri, whereas decreased concomitant flow was found in cingulate, inferior parietal lobule, middle and inferior frontal, supramarginal and precentral gyri. The covariance analysis-derived pattern was then prospectively applied to the cognitively impaired subjects: as compared to subjects with Clinical Dementia Rating (CDR) = 0, subjects with CDR = 0.5 had significantly higher mean covariance pattern expression (P = 0.009). Expression of this pattern correlated inversely with Selective Reminding Test total recall (r = -0.401, P = 0.002), delayed recall (r = -0.351, P = 0.008) and mMMS scores (r = -0.401, P = 0.002) in all three groups combined. We conclude that patients with AD may differentially express resting cerebral blood flow covariance patterns even at very early disease stages. Significant alterations in expression of resting flow covariance patterns occur even for subjects with cognitive impairment. Expression of covariance patterns correlates with cognitive and functional performance measures, holding promise for meaningful associations with underlying biopathological processes.

Cognitive reserve-mediated modulation of positron emission tomographic activations during memory tasks in Alzheimer disease.

BACKGROUND: Cognitive reserve (CR) is the ability of an individual to cope with advancing brain pathological abnormalities so that he or she remains free of symptoms. Epidemiological data and evidence from positron emission tomography suggest that it may be mediated through education or IQ. OBJECTIVE: To investigate CR-mediated differential brain activation in Alzheimer disease (AD) subjects compared with healthy elderly persons. PARTICIPANTS: Using radioactive water positron emission tomography, we scanned 12 AD patients and 17 healthy elderly persons while performing a serial recognition memory task for nonverbalizable shapes under 2 conditions: low demand, in which one shape was presented in each study trial, and titrated demand, in which the study list length was adjusted so that each subject recognized shapes at approximately 75% accuracy. Positron emission tomographic scan acquisition included the encoding and recognition phases. A CR factor score that summarized years of education, National Adult Reading Test estimated IQ, and Wechsler Adult Intelligence Scale-Revised vocabulary subtest score (explaining 71% of the total variance) was used as an index of CR. Voxel-wise, multiple regression analyses were performed with the "activation" difference (titrated demand-low demand) as the dependent variables and the CR factor score as the independent one. Brain regions where regression slopes differed between the 2 groups were identified. RESULTS: The slopes were significantly more positive for the AD patients in the left precentral gyrus and in the left hippocampus and significantly more negative in the right fusiform, right middle occipital, left superior occipital, and left middle temporal gyri. CONCLUSION: Brain regions where systematic relationships (slopes) between subjects' education-IQ and brain activation differ as a function of disease status may mediate the differential ability to cope with (ie, delay or modify) clinical manifestations of AD.