Limiting factors for cytopathological diagnosis of high-grade squamous intraepithelial lesions: a cytohistological correlation between findings in cervical smears and loop electrical excision procedure.

The present study sought possible factors leading to the cytological diagnosis of atypical squamous cells of uncertain significance (ASCUS) in cases of high-grade squamous intraepithelial lesions (HSIL). Based on retrospective histopathological analysis of loop electrical excision procedure (LEEP) products that diagnosed HSIL, two study groups were randomly selected. The first was consisted of cases with two consecutive Papanicolaou (Pap) smears with the diagnosis of ASCUS. The second (control) group was represented by cases diagnosed as HSIL by cytology. From the Pap smears diagnosed as ASCUS, the sampling limitations was different from control group (P < 0.05). The median size of the largest lesion in each case with ASCUS was 2.66 mm (+/- 1.71 mm). In the control group, the median size of the largest lesion was 5.15 mm (+/-2.58 mm) (P < 0.05). The size of the lesion and sample limitations led patients with cervical intraepithelial neoplasms to be diagnosed as ASCUS for two consecutive times, after a 6-mo period.     

Purification and characterisation of toxin B from a strain of Clostridium difficile that does not produce toxin A

Most toxigenic strains of Clostridium difficile produce both toxin A and toxin B. The toxin produced by C. difficile strain 8864 was characterised and compared with those produced by C. difficile strain 10463. Toxin A was not detected by immunoassay in cultures from strain 8864 and all the cytotoxic activity produced by this strain was neutralised by antiserum to toxin B. Toxin B from strain 8864 was purified and compared with toxin B from strain 10463. The size of the purified subunits of toxin B from strain 8864 differed slightly from those of strain 10463 and there were small immunological differences. The effect on fibroblast cells was more like that of C. sordellii cytotoxin than of toxin B from strain 10463. These results suggest that C. difficile strain 8864 produces a modified toxin B and does not produce toxin A.     

Distal colon motility and clinical parameters in depression

Eighty-six patients suffering from nonpsychotic unipolar major depressive disorder, according to Research Diagnostic Criteria, were rated on a modified Hamilton Rating Scale for Depression (HRS). All completed the self-rating Beck Depression Inventory (BDI). Distal colon motility (dcm) studies, performed in all the patients, differentiated two types: low intestinal tone (low-IT) = 40 subjects, and high intestinal tone (high-IT) = 46 subjects. Low-IT depressed patients showed a statistically significant preponderance in the HRS items 'retardation', 'somatization', 'fatigability', 'hypochondriasis' and 'obsessional symptoms'. The high-IT depressed patients, on the other hand, showed preponderance in the items 'guilt', 'suicide', 'insomnia', 'agitation', 'anxiety psychic', 'loss of insight', 'depersonalization' and 'paranoid symptoms'. A positive correlation (r) was found between HRS- and BDI-mean total scores. In addition, a positive correlation (r) was found between HRS scores and distal colon tone in high-IT patients, although the same was not true for low-IT patients. Our results suggest the existence of two subtypes of depressive syndromes, distinguishable on the basis of distal colon motility profiles.     

Nanoarchitectures for efficient IgE cross-linking on effector cells to study amoxicillin allergy

Background

Amoxicillin (AX) is nowadays the β-lactam that more frequently induces immediate allergic reactions. Nevertheless, diagnosis of AX allergy is occasionally challenging due to risky in vivo tests and non-optimal sensitivity of in vitro tests. AX requires protein haptenation to form multivalent conjugates with increased size to be immunogenic. Knowing adduct structural features for promoting effector cell activation would help to improve in vitro tests. We aimed to identify the optimal structural requirement in specific cellular degranulation to AX using well-precised nanoarchitectures of different lengths.

Method

We constructed eight Bidendron Antigens (BiAns) based on polyethylene glycol (PEG) linkers of different lengths (600–12,000 Da), end-coupled with polyamidoamine dendrons that were terminally multi-functionalized with amoxicilloyl (AXO). In vitro IgE recognition was studied by competitive radioallergosorbent test (RAST) and antibody–nanoarchitecture complexes by transmission electron microscopy (TEM). Their allergenic activity was evaluated using bone marrow-derived mast cells (MCs) passively sensitized with mouse monoclonal IgE against AX and humanized RBL-2H3 cells sensitized with polyclonal antibodies from sera of AX-allergic patients.

Results

All BiAns were recognized by AX-sIgE. Dose-dependent activation responses were observed in both cellular assays, only with longer structures, containing spacers in the range of PEG 6000–12,000 Da. Consistently, greater proportion of immunocomplexes and number of antibodies per complex for longer BiAns were visualized by TEM.

Conclusions

BiAns are valuable platforms to study the mechanism of effector cell activation. These nanomolecular tools have demonstrated the importance of the adduct size to promote effector cell activation in AX allergy, which will impact for improving in vitro diagnostics.

     

Endogenous IL-4 and IFN-gamma are essential for expression of Th2, but not Th1 cytokine message during the early differentiation of human CD4+ T helper cells

CD4+ T cells can be divided into several distinct effector subpopulations, including Th1 and Th2. Human Th1 cells are essential for the establishment of cellular immune responses, whereas Th2 cells for immunoglobulin E synthesize by B cells and immunoregulation. This study determines the involvement of exogenously and endogenously produced T cell-derived cytokines during early differentiation of naive CD4+ T cells into Th1 and Th2 cells. Cytokine gene expression of purified experienced and naive CD4+T cells in the presence or absence of Th-directing cytokines and neutralizing anti-cytokine antibodies, was determined at early (20 and 40 h) time points, after in vitro activation. These studies demonstrated that: (1) endogenously produced, T cell-derived cytokines (interferon [IFN]-gamma and interleukin [IL]-4), play an important role in the regulation of early gene expression of Th2, but not Th1 type cytokines; (2) Th1-related cytokines, IFN-gamma, and IL-2, are preferentially expressed in cultures directed toward Th1, as compared with Th2; and (3) IL-4 and IFN-gamma showed early message expression in both differentiating populations, indicating a mixed profile of Th1 and Th2 cytokine production in early human Th cell development. These findings point to the critical role for endogenously produced cytokines in the early differentiation of human Th1 or Th2 cells.     

Humoral immunity to immunodominant epitopes of Hepatitis C virus in individuals infected with genotypes 1a or 1b

Cellular immunity against multiple Hepatitis C virus (HCV) proteins is observed in patients acutely infected with HCV most of whom later resolve infection. We wished to assess humoral immunity in patients infected with HCV 1a or 1b genotypes in relation to viral load using plasma samples from HCV-infected individuals and a panel of peptides representing immunodominant epitopes of HCV structural and nonstructural proteins. Plasma from HCV 1a- and 1b-infected patients, respectively, were divided into two groups: patients with low viral load (<==100,000 RNA copies/ml) and patients with high viral load (>/=10,000,000 RNA copies/ml). The antigens were peptides representing epitopes from immunodominant regions of HCV core, E2, NS3, and NS4 proteins, as well as the hypervariable (HVR) epitopes in E2 from genotypes 1a and 1b. Individuals infected with HCV 1a evoked a stronger immune response to many immunodominant epitopes of HCV relative to individuals infected with HCV 1b. Moreover, among individuals infected with HCV 1a, those with low viral loads mounted significantly greater responses against these epitopes than did individuals with high viral loads. Our observations demonstrate that quantitatively different antibody responses are elicited against HCV depending on the genotype of infecting virus, and suggest that humoral immunity directed against multiple immunodominant epitopes in HCV 1a-infected individuals may help lower viral load in vivo.     

Transition to virtual clinic: Experience in a multidisciplinary clinic for Down syndrome

The COVID‐19 pandemic necessitated a rapid transition from in‐person office visits to virtual visits in the Down syndrome specialty program at Massachusetts General Hospital (MGH DSP). We describe the clinic transition to virtual visits in April 2020 and reflect on our six‐month experience in virtual visits. Clinic metrics were tracked. Electronic survey responses were collected from caregivers attending virtual visits. Input from the MGH DSP team was collected. From April to September 2020, we maintained patient volume (45 visits per month) and overall satisfaction score (6.7 out of 7) following a sudden, unanticipated transition to virtual visits. Survey of 17 caregivers attending virtual visits found that most were equipped with technology, had access to a private location, and most were able to access visit without any limitations. Caregivers appreciated the convenience of virtual visits but sometimes missed the personal connection of an in‐person visit. Overall, though, virtual visits were frequently viewed as no different than office visits. Team members identified benefits and challenges of virtual visits, as well as lessons learned from this transition. We were able to maintain multidisciplinary, specialty care with optimal caregiver feedback and sustained number of patient visits.     

Clinical neurophysiology of dementia

The role of EEG in the study of the dementias is to help in the differential diagnosis of the multiple causes of this syndrome. EEG is useful in differentiating early on between treatable and as of now untreatable forms of dementia. Space-occupying lesions that give rise to dementia are reliably detected by EEG. Infectious, toxic, and metabolic processes are associated with early and severe electroencephalographic abnormalities. The "slow virus" infections show characteristic electrical patterns that reliably distinguish them from the cortical or subcortical dementias. Finally, the EEG may contribute to distinguishing between Alzheimer's disease and MID, two commonly occurring forms of dementia. The paucity of substantial early EEG abnormalities in Alzheimer's disease, although helping to differentiate it from other dementias, leaves us without a currently available physiologic test that provides positive evidence for this condition. Recent studies of EPs, however, suggest that some intermediate latency VEP components may be delayed in patients with Alzheimer's disease when compared with normal subjects. This is encouraging, as latencies in VEPs are more reliable and less variable than amplitude that has previously been reported as "abnormal" in some early Alzheimer patients. Long latency ERPs and CNV also show early abnormalities in Alzheimer's disease. Tests of eye movements such as ERPs are psychophysiologic tests requiring some degree of patient cooperation. Performance on tests of ocular smooth pursuit correlate highly with severity of the dementia syndrome in Alzheimer's disease. In contrast, smooth pursuit testing is usually normal in elderly patients with pseudodementia of depression, suggesting this test may be of some value in differentiating these two clinical disorders. Some evidence exists that smooth pursuit eye movements are also normal, at least in the early and middle stages, in Pick's disease, again suggesting that eye movement testing may prove to have some utility in differentiating this form of dementia from Alzheimer's disease. Ocular scanpaths are abnormal in dementia. They typically are poorly organized and at times perseveratory. In addition, the average durations of eye fixations during directed visual search are altered in dementia as compared with normals. The average eye fixation durations are longer with Alzheimer's disease and briefer in patients with frontal lobe tumors as compared with elderly normal controls. These group differences suggest differing scanning strategies for these two forms of dementia.(ABSTRACT TRUNCATED AT 400 WORDS)     

Gastric Sensory and Motor Functions and Energy Intake in Health and Obesity—Therapeutic Implications

Sensory and motor functions of the stomach, including gastric emptying and accommodation, have significant effects on energy consumption and appetite. Obesity is characterized by energy imbalance; altered gastric functions, such as rapid gastric emptying and large fasting gastric volume in obesity, may result in increased food intake prior to reaching usual fullness and increased appetite. Thus, many different interventions for obesity, including different diets, anti-obesity medications, bariatric endoscopy, and surgery, alter gastric functions and gastrointestinal motility. In this review, we focus on the role of the gastric and intestinal functions in food intake, pathophysiology of obesity, and obesity management.