Digital dual test syphilis/HIV detection based on Fourier Descriptors of Cyclic Voltammetry curves.

BACKGROUND: Effective and timely detection is vital for mitigating the severe impacts of Sexually Transmitted Infections (STI), including syphilis and HIV. Cyclic Voltammetry (CV) sensors have shown promise as diagnostic tools for these STI, offering a pathway towards cost-effective solutions in primary health care settings. OBJECTIVE: This study aims to pioneer the use of Fourier Descriptors (FDs) in analyzing CV curves as 2D closed contours, targeting the simultaneous detection of syphilis and HIV. METHODS: Raw CV signals are filtered, resampled, and transformed into 2D closed contours for FD extraction. Essential shape characteristics are captured through selected coefficients. A complementary geometrical analysis further extracts features like curve areas and principal axes lengths from CV curves. A Mahalanobis Distance Classifier is employed for differentiation between patient and control groups. RESULTS: The evaluation of the proposed method revealed promising results with classification performance metrics such as Accuracy and F1-Score consistently achieving values rounded to 0.95 for syphilis and 0.90 for HIV. These results underscore the potential efficacy of the proposed approach in differentiating between patient and control samples for STI detection. CONCLUSION: By integrating principles from biosensors, signal processing, image processing, machine learning, and medical diagnostics, this study presents a comprehensive approach to enhance the detection of both syphilis and HIV. This setts the stage for advanced and accessible STI diagnostic solutions.

Osteoporosis screening using machine learning and electromagnetic waves.

Osteoporosis is a disease characterized by impairment of bone microarchitecture that causes high socioeconomic impacts in the world because of fractures and hospitalizations. Although dual-energy X-ray absorptiometry (DXA) is the gold standard for diagnosing the disease, access to DXA in developing countries is still limited due to its high cost, being present only in specialized hospitals. In this paper, we analyze the performance of Osseus, a low-cost portable device based on electromagnetic waves that measures the attenuation of the signal that crosses the medial phalanx of a patient's middle finger and was developed for osteoporosis screening. The analysis is carried out by predicting changes in bone mineral density using Osseus measurements and additional common risk factors used as input features to a set of supervised classification models, while the results from DXA are taken as target (real) values during the training of the machine learning algorithms. The dataset consisted of 505 patients who underwent osteoporosis screening with both devices (DXA and Osseus), of whom 21.8% were healthy and 78.2% had low bone mineral density or osteoporosis. A cross-validation with k-fold = 5 was considered in model training, while 20% of the whole dataset was used for testing. The obtained performance of the best model (Random Forest) presented a sensitivity of 0.853, a specificity of 0.879, and an F1 of 0.859. Since the Random Forest (RF) algorithm allows some interpretability of its results (through the impurity check), we were able to identify the most important variables in the classification of osteoporosis. The results showed that the most important variables were age, body mass index, and the signal attenuation provided by Osseus. The RF model, when used together with Osseus measurements, is effective in screening patients and facilitates the early diagnosis of osteoporosis. The main advantages of such early screening are the reduction of costs associated with exams, surgeries, treatments, and hospitalizations, as well as improved quality of life for patients.

Development of a Cyclic Voltammetry-Based Method for the Detection of Antigens and Antibodies as a Novel Strategy for Syphilis Diagnosis.

The improvement of laboratory diagnosis is a critical step for the reduction of syphilis cases around the world. In this paper, we present the development of an impedance-based method for detecting T. pallidum antigens and antibodies as an auxiliary tool for syphilis laboratory diagnosis. We evaluate the voltammetric signal obtained after incubation in carbon or gold nanoparticle-modified carbon electrodes in the presence or absence of Poly-L-Lysine. Our results indicate that the signal obtained from the electrodes was sufficient to distinguish between infected and non-infected samples immediately (T0') or 15 min (T15') after incubation, indicating its potential use as a point-of-care method as a screening strategy.

Enteral feeding in duct-dependent congenital heart disease.

BACKGROUND: Infants with duct-dependent congenital heart lesions are treated with a prostaglandin E1 infusion. We aimed to describe the feeding strategies used at our institution in such infants, and to describe the incidence of necrotising enterocolitis (NEC) in this patient group, investigating whether enteral feeding is associated with a higher risk. METHODS: Patients diagnosed with hypoplastic left heart syndrome, coarctation of the aorta, pulmonary atresia, or transposition of the great arteries born over a defined period were identified. Premature infants, those with pre-existing gastrointestinal disease, and those who never received prostaglandin were excluded. Data were compared using univariable and multivariable logistic regression models. RESULTS: A total of 177 patients were identified, of them 18 received a diagnosis of suspected or confirmed NEC. There was no association between the diagnosis of NEC and enteral feeding (P = 0.9). CONCLUSIONS: Based on these data, there does not appear to be an association between enteral feeding and NEC in infants receiving prostaglandin.

[Bacterial meningitis in adults: a retrospective multicentric study in Tuscany (Italy)]. / Le meningiti batteriche dell'adulto: studio retrospettivo multicentrico della Toscana.

The Infectious Diseases Unit of Lucca Hospital conducted a multicentric retrospective study to evaluate the epidemiological and clinical features of adult patients affected by bacterial meningitis attending all the Infectious Diseases Units of Tuscany (Italy) from July 1999 to June 2004. A specific questionnaire was sent to all the units to collect information about each case of bacterial meningitis occurring in patients older than sixteen. Patients with meningitis by Mycobacterium tuberculosis were excluded from the analysis. Nine out of 12 Infectious Diseases Units of Tuscany took part in the study and 197 cases were identified. Most cases of meningitis occurred during 2002 with a slight reduction in cases in subsequent years. Streptococcus pneumoniae and Neisseria meningitidis were the most frequently isolated pathogens with an increase in diagnosis from 1999 to 2004; in 23.8% of patients no pathogens were isolated, with a reduction in meningitis from unknown aetiology from 1999 to 2004. Most patients were treated with a combination of two antibiotics, and corticosteroid drugs were added to the therapy; in the group of patients treated with corticosteroid drugs invalidating complications occurred in 23% of cases and 5% of patients died. In all, 27 out of 197 subjects (13.7%) developed invalidating complications and 20 out of 197 patients (10.2%) died.

Evaluation of moxifloxacin activity in vitro against Mycobacterium tuberculosis, including resistant and multidrug-resistant strains.

The new quinolone moxifloxacin was tested against 86 strains of Mycobacterium tuberculosis including 13 resistant and 4 multiresistant strains. The antimicrobial susceptibility was tested, in parallel, using two different liquid media, the radiometric Bactec 12B and the Mycobacteria Growth Indicator Tube (Becton Dickinson, USA). All strains but two were susceptible at 0.5 microg/ml of moxifloxacin; for the remaining two strains, both multidrugresistant, the minimal inhibitory concentrations (MIC) were =2 and >4 microg/ml respectively. Our data confirm the high antitubercular in vitro activity of moxifloxacin.

Mycoplasma pneumoniae non-pulmonary infection presenting with pharyngitis, polyarthritis and localized exanthem.

We report a case of pharyngitis, polyarthritis and localized exanthem in acute Mycoplasma pneumoniae infection not involving the lower respiratory tract. Diagnosis was made by means of a particle agglutination test and IgM/IgG indirect immunofluorescence assay. This case describes a clinical complex never reported before and suggests the need for a high index of suspicion in cases of atypical presentation of M. pneumoniae infection.

Extent of human immunodeficiency virus type 1 drug resistance as a predictor of virological failure after genotype-guided treatment switch.

Little is known about factors involved in virological response to treatment changes guided by genotyping in patients whose highly active antiretroviral therapy (HAART) fails. A 12-month observational study was conducted of 45 patients infected with human immunodeficiency virus (HIV)-1, who underwent a new genotype-guided HAART regimen following virological treatment failure. Logistic regression models were used to define factors predictive of virological response to genotype-assisted treatment switches. Virological response was defined as achievement of a level of plasma HIV-1 RNA <1000 copies/mL at the end of the follow-up. Drug-resistance mutations were detected at baseline in 30 patients (66.7%). A sustained virological response to new treatment occurred in 13 (43.3%) of these, as opposed to 11 (73.3%) of the 15 patients harboring drug-susceptible virus at baseline (P=.07). In multivariate logistic regression analysis, the number of drug classes where there was resistance at baseline was the only independent predictor of virological failure (P=.0313). Lack of virological response to genotype-guided treatment changes is primarily due to complex baseline resistance patterns. Benefits of antiretroviral resistance testing may be seriously limited by the lack of subsequent treatment options for heavily pretreated patients.

Differentiation of deception using pupillary responses as an index of cognitive processing.

The deception literature has predominantly focused on detection of guilty individuals using electrodermal measures. Little research has examined other psychophysiological measures or the mechanisms underlying deception. Therefore, the present study examined pupillary responses in a differentiation-of-deception paradigm. Twenty-four undergraduate participants answered the same questions twice, once truthfully and once deceptively, while pupillary responses were recorded. Questions were based on recently learned (episodic) information from scenarios or on general (semantic) knowledge from long-term memory. Task-evoked pupil dilation was significantly greater when participants confabulated responses than when they told the truth for both episodic and semantic memory questions. Previous research has demonstrated that pupil size increases with increased cognitive processing load. The present study suggested that generating deceptive recall was associated with increased pupil size and required greater cognitive processing than truthful recall.

Pupillary responses and processing resources on the visual backward masking task.

Task-evoked pupillary responses were recorded during a visual backward masking task as an index of resource allocation. Increased pupillary dilation indicates increased allocation of processing resources to the task. Consistent with numerous studies, detection accuracy increased with longer interstimulus intervals and approximated no-mask accuracy in the 300-ms condition. Pupillary dilation responses were significantly greater during task performance (cognitive load) than during a passive stimulus viewing condition (no-load) and were significantly greater in the 300-ms condition than the no-mask condition. Consistent with models of early visual information processing, the results suggest that the mask demanded extra processing resources when it followed the target by more than 100 ms. Pupillography methods may be useful in evaluating the contribution and timing of resource-demanding processes during early visual information processing.

Encephalitis without meningitis due to sandfly fever virus serotype toscana.

The role of Toscana (TOS) virus in producing encephalitis without meningitis is uncertain. We studied 2 cases of TOS virus encephalitis without meningitis by means of nested polymerase chain reaction assay and DNA sequencing. Findings confirm that TOS virus may directly cause encephalitis and suggest the usefulness of DNA sequencing in investigating relationships between TOS virus molecular patterns and the spectrum of neurological involvement.

Strongyloides stercoralis: ultrastructural study of newly hatched larvae within human duodenal mucosa.

AIM: To investigate the ultrastructural features of the newly hatched larvae of Strongyloides stercoralis in human duodenal mucosa. METHODS: Duodenal biopsies from an AIDS patient were studied by transmission electron microscopy to investigate morphology, location, and host-worm relations of newly hatched larvae. RESULTS: Newly hatched larvae were found in the Lieberkuhn crypts within the tunnels formed by migration of parthenogenic females. Delimiting enterocytes were compressed. Release of larvae into the gut lumen was also documented. It was shown that both a thin and a thick membrane surrounded the eggs and larvae, as a tegument derived respectively from parasite and host. Segmentary spike-like waves, caused by contractures of worm body musculature, were observed on the surface of newly hatched larvae, and their intestinal lumen was closed and empty, with no budding microvilli. Immaturity of the cuticle and some degree immaturity of amphidial neurones were found, but there was no evidence of either immaturity or signs of damage to other structures. CONCLUSIONS: Newly hatched larvae of S stercoralis appear to be a non-feeding immature stage capable of active movement through the epithelium, causing mechanical damage. The tegument resulting from the thin and the thick membrane may protect the parasite and reduce any disadvantage caused by immaturity.

Encephalitis caused directly by Mycoplasma pneumoniae.

A case of non-fatal encephalitis in a 21-y-old immunocompetent woman is described. High titre serum antibodies against Mycoplasma pneumoniae were found. In addition, Mycoplasma pneumoniae DNA was detected in the cerebrospinal fluid by polymerase chain reaction. Neuroimaging findings by magnetic resonance and computed tomographic scanning of the brain, and laboratory investigations, including a search for serum antibodies to gangliosides, did not support an immune-mediated mechanism. No other pathogens were found. These results strongly suggest that the encephalitis was caused directly by Mycoplasma pneumoniae invasion of the central nervous system. They also indicate that such pathogenetic mechanism may sometimes be sufficient to explain neurological manifestations occurring during the course of Mycoplasma pneumoniae infection. The consequences for therapy are discussed.

Positive and negative schizotypal symptoms relate to different aspects of crossover reaction time task performance.

Although the expressions of both positive and negative symptoms in schizophrenia spectrum illnesses can each occur with varying degrees of severity, researchers have often dichotomized patients as generally positive or negative subtypes. Studies of schizophrenia and schizotypal personality disorder (SPD) have not typically controlled for the severity of the other symptom types when examining the relationship between positive and negative symptom subtypes and cognitive impairment. The present study investigated the relationship between the severity of both symptom types and reaction time crossover task performance in SPD in groups made equivalent on the severity of the other type of symptom. Fifty-eight out of 458 undergraduates were screened into one of four groups (high negative-high positive, low negative-low positive, high negative-low positive or low negative-high positive) by the Schizotypal Personality Questionnaire and assessed with the reaction time crossover task. The results indicated that negative schizotypal symptoms were associated with the early crossover pattern, while positive schizotypal symptoms related to longer overall reaction time. Therefore, different cognitive mechanisms involved in crossover task performance appeared to be associated with different symptom subtypes.

Mycobacterium genavense in AIDS patients, report of 24 cases in Italy and review of the literature.

Mycobacterium genavense is a frequently missed agent of disseminated disease in AIDS patients. The increasing frequency with which such organism is being isolated in Italy suggested a comparison of local survey with data reported in literature. Isolates presumed to belong to the species M. genavense were centralized and identified by means of genomic sequencing and/or HPLC analysis of cell wall mycolic acids; clinical data were obtained from relevant patients' record and collected using a proper questionnaire. In 24 cases in which this organism has been isolated in Italy M. genavense was grown, prevalently from blood, in liquid medium after an average of six weeks of incubation. In overwhelming majority, patients were males, presented other opportunistic diseases and were characterized by very low CD4+ counts (average 23/microl); most frequent symptoms were fever, anemia and weight loss. All but two patients, who died before the mycobacterial infection was diagnosed, were treated with at least three drugs; the mean survival was close to one year. A review of literature reports revealed a wide overlapping of clinical and microbiological features.

Chronic cryptosporidiosis in patients with AIDS: stable remission and possible eradication after long-term, low dose azithromycin.

AIMS: To investigate the effectiveness of long term, low dose azithromycin treatment for chronic cryptosporidiosis in patients with AIDS. METHODS: Azithromycin was administered as initial daily treatment to 13 patients with AIDS: 6 patients received 500 mg for 30 to 40 days (mean 35); 3 patients received 1000 mg for 21 to 50 days (mean 37); and 4 patients received 1500 mg for 20 days. Nine of the 13 patients were also given low dose maintenance treatment with different schedules of azithromycin for 30 to 360 days (mean 129). Patients were monitored, during and after treatment, for parasite shedding in stool and for daily stool frequency and body weight. All but one patient had severe immunodeficiency. RESULTS: Long term, low dose maintenance treatment was associated with major clinical and parasitological benefits: there was probable eradication of infection in 2 patients, and 7 patients showed a complete response with persistent high decrease (5 patients) or clearance (2 patients) of parasite in stool. The drug was well tolerated, and there was no relapse either during treatment or during follow up (up to 21 months). These results were more impressive than those observed after the short term initial course of azithromycin, which was unable at any tested dose to achieve parasite clearance in stool (except in the patient with less advanced immunodeficiency) or to prevent relapse in 3 patients who discontinued treatment. Reversible side effects occurred with the 1500 mg daily dose. CONCLUSIONS: Long term, low dose azithromycin is well tolerated and may induce stable remission of chronic cryptosporidiosis in patients with AIDS. It may lead to probable eradication of the infection in some patients, even those with severe immunodeficiency.