Wearable Ring-Shaped Biomedical Device for Physiological Monitoring through Finger-Based Acquisition of Electrocardiographic, Photoplethysmographic, and Galvanic Skin Response Signals: Design and Preliminary Measurements.

Wearable health devices (WHDs) are rapidly gaining ground in the biomedical field due to their ability to monitor the individual physiological state in everyday life scenarios, while providing a comfortable wear experience. This study introduces a novel wearable biomedical device capable of synchronously acquiring electrocardiographic (ECG), photoplethysmographic (PPG), galvanic skin response (GSR) and motion signals. The device has been specifically designed to be worn on a finger, enabling the acquisition of all biosignals directly on the fingertips, offering the significant advantage of being very comfortable and easy to be employed by the users. The simultaneous acquisition of different biosignals allows the extraction of important physiological indices, such as heart rate (HR) and its variability (HRV), pulse arrival time (PAT), GSR level, blood oxygenation level (SpO2), and respiratory rate, as well as motion detection, enabling the assessment of physiological states, together with the detection of potential physical and mental stress conditions. Preliminary measurements have been conducted on healthy subjects using a measurement protocol consisting of resting states (i.e., SUPINE and SIT) alternated with physiological stress conditions (i.e., STAND and WALK). Statistical analyses have been carried out among the distributions of the physiological indices extracted in time, frequency, and information domains, evaluated under different physiological conditions. The results of our analyses demonstrate the capability of the device to detect changes between rest and stress conditions, thereby encouraging its use for assessing individuals' physiological state. Furthermore, the possibility of performing synchronous acquisitions of PPG and ECG signals has allowed us to compare HRV and pulse rate variability (PRV) indices, so as to corroborate the reliability of PRV analysis under stationary physical conditions. Finally, the study confirms the already known limitations of wearable devices during physical activities, suggesting the use of algorithms for motion artifact correction.

Wearable Multisensor Ring-Shaped Probe for Assessing Stress and Blood Oxygenation: Design and Preliminary Measurements.

The increasing interest in innovative solutions for health and physiological monitoring has recently fostered the development of smaller biomedical devices. These devices are capable of recording an increasingly large number of biosignals simultaneously, while maximizing the user's comfort. In this study, we have designed and realized a novel wearable multisensor ring-shaped probe that enables synchronous, real-time acquisition of photoplethysmographic (PPG) and galvanic skin response (GSR) signals. The device integrates both the PPG and GSR sensors onto a single probe that can be easily placed on the finger, thereby minimizing the device footprint and overall size. The system enables the extraction of various physiological indices, including heart rate (HR) and its variability, oxygen saturation (SpO2), and GSR levels, as well as their dynamic changes over time, to facilitate the detection of different physiological states, e.g., rest and stress. After a preliminary SpO2 calibration procedure, measurements have been carried out in laboratory on healthy subjects to demonstrate the feasibility of using our system to detect rapid changes in HR, skin conductance, and SpO2 across various physiological conditions (i.e., rest, sudden stress-like situation and breath holding). The early findings encourage the use of the device in daily-life conditions for real-time monitoring of different physiological states.

Adaptive scheduling of acceleration and gyroscope for motion artifact cancelation in photoplethysmography.

BACKGROUND AND OBJECTIVE: Recently, various algorithms have been introduced using wrist-worn photoplethysmography (PPG) to provide high accuracy of instantaneous heart rate (HR) estimation, including during high-intensity exercise. Most studies focus on using acceleration and/or gyroscope signals for the motion artifact (MA) reference, which attenuates or cancels out noise from the MA-corrupted PPG signals. We aim to open and pave the path to find an appropriate MA reference selection for MA cancelation in PPG. METHODS: We investigated how the acceleration and gyroscope reference signals correlate with the MAs of the distorted PPG signals and derived both mathematically and experimentally an adaptive MA reference selection approach. We applied our algorithm to five state-of-the-art (SOTA) methods for the performance evaluation. In addition, we compared the four MA reference selection approaches, i.e. with acceleration signal only, with gyroscope signal only, with both signals, and using our proposed adaptive selection. RESULTS: When applied to 47 PPG recordings acquired during intensive physical exercise from two different datasets, our proposed adaptive MA reference selection method provided higher accuracy than the other MA selection approaches for all five SOTA methods. CONCLUSION: Our proposed adaptive MA reference selection approach can be used in other MA cancelation methods and reduces the HR estimation error. SIGNIFICANCE: We believe that this study helps researchers to address acceleration and gyroscope signals as accurate MA references, which eventually improves the overall performance for estimating HRs through the various algorithms developed by research groups.

Eosinophil-Specific Granules in Tumor Cell Cytoplasm: Unusual Ultrastructural Findings in a Case of Diffuse-Type Gastric Carcinoma.

A case of desmoplastic variant of diffuse-type gastric carcinoma in a 72-year-old woman is reported. Microscopic findings included poorly cohesive tumor cells, resembling mononuclear inflammatory cells, prominent diffuse desmoplasia, and tumor-associated tissue eosinophilia. Electron microscopy confirmed the undifferentiated phenotype of tumor cells and disclosed activated eosinophils in the tumor stroma. Eosinophil-specific granules were found either free in the tumor stroma or within the cytoplasm of some tumor cells. Electron microscopy provided also circumstantial evidence of phagocytosis of apoptotic eosinophils by tumor cells. Extracellular, membrane-bound, eosinophil-specific granules have been long recognized in tissues associated with eosinophilia, including allergic diseases, inflammatory responses to helminths, and in stroma of some neoplasms. Our ultrastructural study now extends these findings and provides additional morphological evidence of eosinophil-specific granules within the cytoplasm of gastric carcinoma cells.

Neutrophil-rich gastric carcinoma in the integrated cancer registry of eastern Sicily, Italy.

BACKGROUND/AIM: Neutrophil-rich carcinoma is a variant of gastric carcinoma that has not been well-studied or characterized. The purpose of the present study was to reveal the incidence and clinicopathological findings compared to ordinary gastric carcinoma. PATIENTS AND METHODS: A population-based series of 430 gastric cancers, identified between 2003 and 2006 from the province of Messina (insular Italy; population, 662,450), was used. The number of tumor-infiltrating neutrophils was assessed in a semi-quantitative manner using the mean value of 20 non-overlapping high-power fields (magnification, 400; 0.08 mm(2)). Tumors with >10 neutrophils per 20 high-power fields were arbitrarily considered as neutrophil-rich gastric carcinomas. Moreover, MUC1 immunohistochemical expression was investigated to show possible correlation with neutrophil infiltration in gastric carcinomas. RESULTS: Among 193 gastric cancers resected for curative purposes, 30 (15.54%) were represented by neutrophil-rich gastric carcinomas. These tumors occurred more frequently in patients aged more than 72 years (p<0.05), showing an inverse correlation with mucinous subtype according to the WHO classification (p<0.001) and expressed MUC1. However, intensity and distribution of MUC1 was heterogeneous, and independent of neutrophil infiltration within the tumor stroma. CONCLUSION: Neutrophil-rich carcinoma seems to represent a distinctive morphological variant of gastric carcinoma, although the true mechanism for the infiltration of neutrophils is still unclear.

Histologic coagulative tumour necrosis as a prognostic indicator of aggressiveness in renal, lung, thyroid and colorectal carcinomas: A brief review.

Tumour growth involves two essential deviations from the normal state including the induction of proliferative stimuli, and simultaneous suppression of potentially compensatory cell death. It has been suggested that the development of invasive cancer involves a progressive switch from predominantly apoptotic to necrotic tumour cell death. The presence of tumour necrosis in pathologic specimens may not only reflect tumour biology, but also provide additional beneficial prognostic information. This review emphasises the role of tumour necrosis as an additional prognostic factor for patients with certain types of epithelial neoplasms.

Chronic allergic-like inflammation in the tumor stroma of human gastric carcinomas: an ultrastructural study.

Inflammatory cell infiltration around the sites of carcinoma invasion is believed to play important roles in tumor biological behavior. The status of inflammatory cell infiltration at the sites of frank invasion in 92 cases of gastric carcinomas was examined, with special emphasis on tumor-associated tissue eosinophilia (TATE). TATE was found in 7 out of 92 (7.6%) gastric carcinomas (6 of intestinal-type and 1 of diffuse-type). Electron microscopy, selectively performed in the 7 cases of gastric carcinomas with TATE, showed that eosinophils participated in the stromal reaction by interacting with tumor cells, mast cells, and each other. Most of the tumor-infiltrating mast cells exhibited anaphylactic or piecemeal degranulation, indicating that the mast cells had been activated in situ. Some mast cells were noted in close contact to viable tumor cells, suggesting the existence of direct cell-to-cell interactions. There was also extracellular deposition of free eosinophil granules and Charcot-Leyden crystals. These morphologic findings are similar to that described in late/chronic-phase allergic reaction in both human and experimental animals, where angiogenesis and fibrosis/tissue repair are also present. In conclusion, TATE may indicate a chronic allergic-like Th2 host-tumor reaction, and understanding these pathways should create tools to enhance defence and contrast neoplastic disease.

Intraepithelial infiltration by mast cells in human Helicobacter pylori active gastritis.

Recent observations suggest an involvement of mast cells in Helicobacter pylori gastritis, but the mechanism of intraepithelial mast cell activation in H. pylori-infected patients remains to be clarified. Intraepithelial mast cells, identified by immunohistochemistry for CD117, were quantified in antral biopsies from 6 patients with H. pylori "active" chronic gastritis, 7 patients with H. pylori "nonactive" gastritis, and 9 controls. Antral biopsies from patients with H. pylori "active" gastritis showed higher intraepithelial mast cell counts than those from patients with H. pylori "nonactive" gastritis and from controls. Electron microscopy, selectively performed in 6 cases of H. pylori "active" gastritis, confirmed the presence of intraepithelial mast cells and allowed their subdivision into mature cells with intact electron-dense granules or degranulated cells. Other mast cells appeared to migrate through defects in the basement membrane into the epithelial layer. Mast cells in these areas often showed piecemeal degranulation or were characterized by large canaliculi, expanded Golgi areas, and a few granules, a process similar to the phase of recovery from anaphylactic degranulation of isolated human mast cells. The possible significance of these unusual ultrastructural findings is discussed.

Ultrastructural descriptions of heterotypic aggregation between eosinophils and tumor cells in human gastric carcinomas.

A histological variant of gastric adenocarcinoma, characterized by an intense tumor-associated tissue eosinophilia (TATE), has been occasionally reported in the literature. The purpose of this ultrastructural study was to determine the interactions between frequently occurring eosinophils and tumor cells in gastric carcinoma characterized by TATE. Fresh tumor tissue of 92 gastric carcinomas was processed for both light and electron microscopic examination. Intense TATE was found in 7 out of 92 (7.6%) gastric carcinomas (6 of intestinal-type and 1 of diffuse-type). Electron microscopy, selectively performed in 7 cases with intense TATE, revealed eosinophils, singly or in groups, in contact with damaged or necrotic tumor cells. Activated eosinophils showing piecemeal degranulation were also found in intimate contact with viable tumor cells, characterized by plasma membrane caveolar invaginations. The authors regard this close morphological relationship as in vivo evidence for possible cross-talk between eosinophil and viable tumor cell, a conclusion that has already been drawn from experimental studies, but until now inadequately supported by ultrastructural observations in a human tumor.

Mitotic catastrophe in malignant epithelial tumors: the pathologist's viewpoint.

Mitotic catastrophe is a common phenomenon occurring in tumor cells with impaired p53 function exposed to various cytotoxic and genotoxic agents. The defective p53 checkpoint causes improper segregation of chromosomes, resulting in aberrant mitosis, multiple micronuclei, multinucleate giant cells, and eventual necrosis-like death and centrosome aberration. Although various descriptions explaining mitotic catastrophe exist, there is still no generally accepted definition of this phenomenon. However, the syndrome of mitotic catastrophe may be a unifying morphological concept of particular interest to cancer research, as it integrally links cell death to checkpoints of the cell cycle. Morphological findings compatible with mitotic catastrophe may be found in pleomorphic, giant cell carcinomas--neoplasms characterized by a poor prognosis. The inclusion of mitotic catastrophe as part of the microscopic evaluation of tumors will add further insight to the pathobiology of tumor progression and in novel therapeutic designs. Finally, the possibility of assimilating mitotic catastrophe into a prognostic score is discussed.

Abnormal nuclear structures (micronuclei, nuclear blebs, strings, and pockets) in a case of anaplastic giant cell carcinoma of the thyroid: an immunohistochemical and ultrastructural study.

The authors report a case of a 70-year-old woman with an anaplastic giant cell thyroid carcinoma, along with immunohistochemical and electron microscopic findings. Histologically, the tumor is characterized by mononucleated and multinucleated giant cells, lack of architectural cohesion, atypical mitoses, and extensive areas of coagulative necrosis. Tumor cells showed AE1/AE3 positivity as well as nuclear overexpression of p53 and ki-67. Semithin sections revealed multiple nuclei with heterogeneous size ranging from micronuclei to large-size (giant) nuclei. Micronuclei were confirmed by electron microscopy that disclosed also the presence of nuclear blebs, strings, and pockets. Morphological findings of these abnormal nuclear structures in conjunction with p53 and Ki-67 nuclear overexpression suggested a faulty mitotic checkpoint/mitotic catastrophe in the progression of anaplastic giant cell thyroid carcinoma.

Mitochondrion-rich differentiated adenocarcinomas of the stomach: clinicopathological, immunohistochemical and electron microscopy study of nine cases.

Pathologic and prognostic data of nine patients with mitochondrion-rich carcinomas (MRC) were compared retrospectively to data of 101 patients with conventional gastric adenocarcinomas. MRC was defined as a tumour composed predominantly, or entirely, of columnar adenocarcinoma cells with eosinophilic cytoplasm and a strong supranuclear immunoreactivity for antimitochondrial antibody. Electron microscopy confirmed supranuclear distribution of mitochondria in MRC while immunostaining pattern was irregular or absent in the remaining 101 cases. MRC exhibited a tubulopapillary or cribriform growth pattern with focal infiltration of neutrophils in the tumour stroma. Prominent necrosis was present including segmental and intraluminal "dirty necrosis", while mitotic and ki-67 proliferative rates were low. MRC showed immunohistochemical findings compatible with gastric differentiation (CK7+/CK20-/CDX-) When MRC were compared with non-MRC carcinomas, tumour size (< 4 cm vs >4 cm, P < 0.01) , frequency of lymph node metastases (11% vs. 80%, P < 0.01), low stage (I, II) at diagnosis (100% vs. 56%, P < 0.01), Goseki's group I (100% vs. 6%, P < 0.01), and better survival (0% vs. 70%, P < 0.01) differed significantly. Our results suggest that MRC of the stomach may be considered a low-grade malignancy with an excellent prognosis.

Integrated Optic Surface Plasmon Resonance Measurements in a Borosilicate Glass Substrate.

The surface plasmon resonance (SPR) technique is a well-known optical method that can be used to measure the refractive index of organic nano-layers adsorbed on a thin metal film. Although there are many configurations for measuring biomolecular interactions, SPR-based techniques play a central role in many current biosensing experiments, since they are the most suited for sensitive and quantitative kinetic measurements. Here we give some results from the analysis and numerical elaboration of SPR data from integrated optics experiments in a particular borosilicate glass, chosen for its composition offering the rather low refractive index of 1.4701 at 633 nm wavelength. These data regard the flow over the sensing region (metal window) of different solutions with refractive indexes in the range of interest (1.3÷1.5) for the detection of contaminants in aqueous solutions. After a discussion of the principles of SPR, of the metal window design optimization by means of optical interaction numerical modeling, and of waveguide fabrication techniques, we give a description of system setup and experimental results. Optimum gold film window thickness and width in this guided-wave configuration has been for the first time derived and implemented on an integrated optic prototype device. Its characterization is given by means of the real time waveguide output intensity measurements, which correspond to the interaction between the sensing gold thin film window and the flowing analyte. The SPR curve was subsequently inferred. Finally, a modified version of the device is reported, with channel waveguides arranged in a Y-junction optical circuit, so that laser source stability requirements are lowered by a factor of 85 dB, making possible the use of low cost sources in practical applications.

Nonstoichiometric silica mask for fabricating reverse proton-exchanged waveguides in lithium niobate crystals.

Producing channel waveguides requires a photolithographic mask, but the standard technique of using thermally evaporated metal films for proton exchange has proved to be unsuitable for withstanding the rather aggressive process of reverse proton exchange. We report the fabrication of a nonstoichiometric silica mask by ion-plating plasma-assisted deposition. This mask is strong enough to resist both direct and reverse proton exchange and is also compatible with anisotropic dry etching for patterning the mask and with electric field poling. Our technique is a practical alternative to the use of SiO2 sputtered masks.

A case of gastric adenocarcinoma associated with giant-cell phlebitis.

A 60-year-old male patient with advanced gastric adenocarcinoma was treated by subtotal gastrectomy with dissection of the regional lymph nodes. Microscopic examination of the tumour revealed tubular adenocarcinoma which invaded the muscularis propria. There was no evidence of metastatic carcinoma in the dissected lymph nodes (pT2N0Mx). Granulomatous reaction comprising epithelioid cells and giant cells involved subserosal muscular veins, adjacent to the carcinoma tissue. Fibrinoid necrosis, with or without infiltration of eosinophils, was noted within the lumen of some veins. The acid-fast and fungal stains were negative. Remnants of parasites were not identified in serial sections of the paraffin blocks. No pulmonary disease was evident on radiographic or pulmonary examination. The presence of granulomatous destruction of muscular veins with sparing of arteries suggested the diagnosis of giant-cell phlebitis. To our knowledge, there have been no previous reports regarding an association between giant-cell phlebitis and advanced gastric adenocarcinoma.

[Voluntary or accidental ingestion of foreign bodies: clinical considerations in 142 cases]. / L'ingestione volontaria o accidentale di corpi estranei: considerazioni cliniche su 142 casi.

The authors report on a series of 142 patients who had swallowed foreign bodies over the period 1981-1999. After outlining the various ways in which the foreign bodies were swallowed and the fact that they were eliminated spontaneously by natural routes in 80-90% of cases, the authors deal at some length with the serious complications that occurred in some of these cases, which, as a result of their characteristics and mode of ingestion, may require emergency surgery for their resolution. In particular, the authors describe 6 cases of foreign bodies that were urgently removed by endoscopy and also describe 3 cases in detail (1 perforation and 2 bowel obstructions) in which a laparotomy was required not only to correct the complication but also to definitively clarify the diagnosis.

[Role of ultrasonographic imaging in the surgical management of acute diverticulitis of the colon]. / Ruolo dell'imaging ultrasonografico nell'approccio chirurgico alla diverticolite acuta del colon.

Diverticulosis of the colon is a very frequent pathology in the western word and is characterised by a high percentage of dangerous complications (10-25%). The most accurate method of staging diverticular disease is by CT scan. The aim of our study was to evaluate the sensitivity of ultrasonography in the evaluation and management of diverticular disease of the colon. We studied 51 patients: the parameters used to assess complicated diverticulosis of the colon were: 1) wall thickness; 2) presence of fluid collections and pericolic abscesses; 3) free liquid collections in the peritoneal cavity; 4) subdiaphragmatic free air; 5) presence of fistula tracts. Ultrasonography showed 66% sensitivity in the assessment of wall thickness and in detecting the presence of diverticula. The sensitivity rate was 100% in the detection of abscess complications, pericolic collections, free air and fistula tracts. False-negatives (5 patients) were all recorded in Hinchey stage I. The overall sensitivity amounted to 91%. In our experience the method is a first level examination in the approach to patients suffering from diverticular disease of the colon and presents high sensitivity and diagnostic accuracy. The method, in expert hands, is suggested as a first step in the clinical-diagnostic approach to patients suffering from acute abdomen due to diverticulitis of the colon.