Frailty Reduces Vaccine Effectiveness Against SARS-CoV-2 Infection: A Test-Negative Case Control Study Using National VA Data.

OBJECTIVES: To assess the variation of vaccine effectiveness against SARS-CoV-2 infection during the Delta wave according to frailty status among U.S. veterans. DESIGN: Test-negative case-control study of SARS-CoV-2 mRNA vaccine effectiveness. SETTING: Veterans Health Administration (VHA) medical centers. PARTICIPANTS: Veterans 19 years and older who had at least one COVID-19/Flu like symptoms and received a SARS-CoV-2 PCR or antigen test at VHA medical centers between July 25 to September 30, 2021. INTERVENTION: mRNA vaccination. MEASUREMENTS: New SARS-CoV-2 infection. Vaccine effectiveness was defined as 1-odds of vaccination in cases/odds of vaccination in controls, where cases were patients who had a COVID-19 test and tested positive for SARS-CoV-2, and controls were those who tested negative. Frailty was measured using the VA frailty index, categorized as robust (0-<0.1), pre-frail (≥0.1-<0.21) and frail (≥0.21). RESULTS: A total of 58,604 patients (age:58.9±17.0, median:61, IQR:45-72; 87.5%men; 68.1%white; 1.3%African American, 8.3%Hispanic) were included in the study. Of these, 27,733 (47.3%) were robust, 16,276 (27.8%) were prefrail, and 14,595 (24.9%) were frail. mRNA vaccine effectiveness against the Delta variant symptomatic infection was lower in patients with frailty, 62.8 %(95%CI:59.8-65.7), versus prefrail 73.9%(95%CI:72.0-75.7), and robust, 77.0 %(95%CI:75.7-78.3). CONCLUSIONS: This test-negative case control study showed that mRNA vaccine effectiveness against infection declined in veterans with frailty. Frailty status is a factor to consider when designing, developing, and evaluating COVID-19 vaccines.

Differences in the volume distributions of human lung mast cell granules and lipid bodies: evidence that the size of these organelles is regulated by distinct mechanisms.

We analyzed transmission electron micrographs of human lung mast cells by digitized planimetry and point counting to determine the cross-sectional areas of two distinct cytoplasmic organelles: specific granules and lipid bodies. Specific granules have a limiting membrane and often contain one or more cylindrical scroll-like inclusions. By contrast, lipid bodies are on average much larger than granules and lack both limiting membranes and inclusions. The measured cross-sectional areas of lipid bodies and scroll-containing granules were converted to equivalent volumes, and the noise in the frequency distribution of these volumes was smoothed using a moving bin technique. This analysis revealed (a) a periodic, multimodal distribution of granule equivalent volumes in which the modes fell at volumes that were integral multiples of the volume defined by the first mode (the "unit volume"), and (b) a modal granule equivalent volume frequency that occurred at a magnitude equal to four "unit volumes." Thus, specific granules appear to be composed of units of a narrowly fixed volume. Furthermore, the mean volume of intragranule inclusions was 0.0061 mu3, a value very similar to that calculated for the "unit volume" (0.0071 mu3). This result suggests that each "unit volume" comprising the individual scroll-type granules contains (or is capable of generating or accommodating) a single scroll-like inclusion. In contrast to the specific granules, mast cell lipid bodies lack a periodic, multimodal volume distribution. Taken together, these findings suggest that the volumes of human lung mast cell granules and lipid bodies are regulated by distinct mechanisms.

Differences in the behavior of cytoplasmic granules and lipid bodies during human lung mast cell degranulation.

We used a morphometric and autoradiographic approach to analyze changes in specific cytoplasmic granules and cytoplasmic lipid bodies associated with human lung mast cell degranulation. Mast cells were dissociated from lung tissue by enzymatic digestion and were then enriched to purities of up to 99% by countercurrent centrifugation elutriation and recovery from columns containing specific antigen bound to Sepharose 6 MB. Degranulation was induced by goat anti-IgE. At various intervals after stimulation, parallel aliquots of cells were recovered for determination of histamine release or were fixed for transmission electron microscopy. We found that lipid bodies, electron-dense structures that lack unit membranes, were present in both control and stimulated mast cells. Autoradiographic analysis showed that lipid bodies represented the major repository of 3H-label derived from [3H]arachidonic acid taken up from the external milieu. By contrast, the specific cytoplasmic granules contained no detectable 3H-label. In addition, lipid bodies occurred in intimate association with degranulation channels during mast cell activation, but the total volume of lipid bodies did not change during the 20 min after stimulation with anti-IgE. This result stands in striking contrast to the behavior of specific cytoplasmic granules, the great majority of which (77% according to aggregate volume) exhibited ultrastructural alterations during the first 20 min of mast cell activation. These observations establish that mast cell cytoplasmic granules and cytoplasmic lipid bodies are distinct organelles that differ in ultrastructure, biochemistry, and behavior during mast cell activation.

Unequivocal delayed hypersensitivity in mast cell-deficient and beige mice.

It has been suggested that reserpine blocks expression of delayed hypersensitivity in mice because it depletes stores of the vasoactive amine serotonin in mast cells. To determine whether mast cell serotonin or other mast cell-derived mediators are essential for delayed hypersensitivity, responses to contact sensitizers in mast cell-deficient W/Wv or Sl/Sld mice were studied. Because blood platelets represent another potential source of serotonin in delayed hypersensitivity responses, beige mice, whose platelets contain less than 1 percent of the normal levels of serotonin, were also examined. By the criteria of tissue swelling, infiltration of iodinated leukocytes, or histology, mast cell-deficient or beige mice expressed delayed hypersensitivity reactions whose intensity generally equaled or exceeded that of reactions in littermate controls. In addition, reserpine blocked delayed hypersensitivity in W/Wv and beige mice, suggesting that effects on mast cell or platelet serotonin cannot explain this drug's action in delayed hypersensitivity.

Osteopenia, hematopoiesis, and bone remodelling in iliac crest and femoral biopsies: a prospective study of 102 cases of femoral neck fractures.

Cancellous microanatomy, bone remodelling, and hematopoietic tissue were studied in iliac crest and femoral neck biopsies taken intraoperatively in 102 consecutive patients with displaced intracapsular fractures. About half of the femoral biopsies had osteopenia, and most showed replacement of hematopoietic tissue by fat cells, with absence of osteoblasts and osteoclasts. In contrast, most of the iliac crest biopsies showed relatively less decrease in cancellous bone, while hematopoietic tissue and bone remodelling cells were present in approximately 75%. These results indicate that the iliac crest biopsy does not necessarily reflect cancellous microanatomy, hematopoietic tissue, and bone remodelling at other skeletal sites in any given patient.

Progression of errors in morphometry. Estimation of particle number density.

We have developed procedures whereby the progression of errors in various methods of morphometric data extrapolation may be evaluated. The analysis is straightforward and simple. We suggest that before collecting data, one should estimate the accepted fluctuations of the various parameters. Then, by calculation of propagation of errors, the most suitable method may be chosen, so that the data extracted will have an acceptable coefficient of variation. Higher precision carries a cost of time and/or money, and may not be necessary.

Morphometric analysis of gold particles in low-label cell compartments.

Quantitative estimation of the binding of gold-conjugated ligands to various cell organelles has become a commonly used method to quantify the amount of ligand-binding sites associated with those organelles. However, often a small percentage of organelles is labeled or the density of gold labeling is low. We have defined the "gold-labeled region" as a zone that has a boundary defined by the localization of the outermost gold particles. Such a phenomenon was recently observed in a study of the internalization of gold-labeled native surfactant into lamellar bodies of cultured pulmonary type II cells. We estimated the size and density of gold-labeled regions in lamelar bodies using a simple stereological approach and demonstrated that the low percentage of gold-labeled organelles can be explained as a result of the probability of random selecting through the labeled areas. Our method, which permits use of transmission electron microscopy to calculate the true parameters of gold-labeled regions, can significantly facilitate analyses of ligand binding to various cell compartments.

Changes in the distribution of anionic constituents in secretory granules of mouse pancreatic acinar cells after pilocarpine-induced degranulation.

We used cationized colloidal gold (CCG) to investigate the distribution of anionic sites in different secretory granules of mouse pancreatic acinar cell regranulation. Localization of anionic sites with CCG was carried out on ultrathin sections of a mouse pancreas, fixed in Karnovsky's fixative and OsO4 and embedded in Araldite. After pilocarpine-stimulated degranulation, there was a marked diminution in the anionic charge density of immature and mature granules of the 4-hr group (approximately 43.0 gold particles/microm2) compared to the 8-hr mature granules group (approximately 64.6 gold particles/microm2). Scattergram analysis to investigate the correlation between section profile size and cationized gold labeling density revealed a reverse correlation, the small granule profiles demonstrated a higher density compared to the larger profiles of the same group. On the basis of these observations, it appears that a post-translational processing of secretory content influences the granule anionic charge and thus may affect the intragranular buffer capacity.

Evaluation of atrial natriuretic peptide and brain natriuretic peptide in atrial granules of rats with experimental congestive heart failure.

The natriuretic peptides are believed to play an important role in the pathophysiology of congestive heart failure (CHF). We utilized a quantitative cytomorphometric method, using double immunocytochemical labeling, to assess the characteristics of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) in atrial granules in an experimental model of rats with CHF induced by aortocaval fistula. Rats with CHF were further divided into decompensated (sodium-retaining) and compensated (sodium-excreting) subgroups and compared with a sham-operated control group. A total of 947 granules in myocytes in the right atrium were analyzed, using electron microscopy and a computerized analysis system. Decompensated CHF was associated with alterations in the modal nature of granule content packing, as depicted by moving bin analysis, and in the granule density of both peptides. In control rats, the mean density of gold particles attached to both peptides was 347.0 +/- 103.6 and 306.3 +/- 89.9 gold particles/microm2 for ANP and BNP, respectively. Similar mean density was revealed in the compensated rats (390.6 +/- 81.0 and 351.3 +/- 62.1 gold particles/microm2 for ANP and BNP, respectively). However, in rats with decompensated CHF, a significant decrease in the mean density of gold particles was observed (141.6 +/- 67.3 and 158.0 +/- 71.2 gold particles/microm2 for ANP and BNP, respectively; p<0.05 compared with compensated rats, for both ANP and BNP). The ANP:BNP ratio did not differ between groups. These findings indicate that the development of decompensated CHF in rats with aortocaval fistula is associated with a marked decrease in the density of both peptides in atrial granules, as well as in alterations in the quantal nature of granule formation. The data further suggest that both peptides, ANP and BNP, may be regulated in the atrium by a common secretory mechanism in CHF.

Morphological evidence for chronic mast cell activation after prolonged exposure with supernatants from chronic graft-versus-host splenocytes.

Chronic graft-vs.-host disease (cGVHD) includes a syndrome of inflammatory and fibrotic changes in some respects resembling scleroderma. In the present study we have quantitated the number of peritoneal mast cells (MC) in mice with cGVHD induced across minor histocompatibility barriers. MC were evaluated by staining with toluidine blue. The number of MC decreased significantly (by 25%) at the onset of the cGVHD fibrosis (day 12). Around day 35, MC were virtually undetectable, and started to reappear on day 130. Upon clinical recovery (day 200) a dramatic increase in MC numbers was found (about 8-fold). In addition, we evaluated by electron microscopy the morphology of peritoneal MC, obtained from normal mice and rats, that had been co-cultured on 3T3 fibroblast monolayer in the presence of splenocyte supernatants from mice with cGVHD or from control mice. After 6-8 days of continuous incubation with the cGVHD splenocyte supernatant, MC appeared to be activated, since they displayed an array of heterogenous granules. Few of the granules were dense; many were swollen and pale. Rare granule extrusion was evident. This would indicate that MC underwent a slow activation process due to a factor(s) present in the cGVHD supernatant, different from the classical acute anaphylactic activation.

Lipid pigment (lipofuscin) accumulation in rat tongue muscle with aging.

Lipid pigment (lipofuscin) was examined in perioral and tongue muscles of aging rats. While in perioral striated muscle the pigmented granules could not be found, a considerable accumulation with aging could be noted in the tongue muscle. Unlike the human tongue muscle, in which the pigmented granules were stored in clusters of different sizes at the nuclear poles of the muscle fibers, in rats, they were scattered randomly through the cytoplasm. The results of this study suggest that lipofuscin can be used as a marker for aging of the tongue muscle in the rat.

Histochemical study of the blue autofluorescence of collagen in oral irritation fibroma: effects of age of patients and of the duration of lesions.

The intensity of the autofluorescence of collagen was measured in 27 irritation fibromata of the buccal mucosa and 13 of the lip. The intensity of fluorescence correlated positively with the duration of the lesion. The fluorescence intensity also increased with the patients' age. The present observations show that in irritation fibromata of buccal and lip mucosae, the intensity of blue autofluorescence of the collagen increases with duration of the lesions and with the age of patients.

Decelerated rate of dendrite outgrowth from dopaminergic neurons in primary cultures from brains of hypoxanthine phosphoribosyltransferase-deficient knockout mice.

Lesch-Nyhan syndrome (LNS), caused by the complete deficiency of hypoxanthine phosphoribosyltransferase (HPRT), is characterized by a neurological deficit, the etiology of which is still unclear. Evidence has accumulated indicating that it reflects dopamine deficiency associated with defective arborization of dopaminergic dendrites. We monitored the differentiation in vitro of dopaminergic neurons, cultured from HPRT-deficient knockout mice. The HPRT-deficient dopaminergic neurons exhibited a decelerated rate of outgrowth of dendrites in comparison to that of control neurons resulting, after 8 days in culture, in 32% smaller average total length of dendrites per neuron (P<0.025). The results suggest that the abnormal dendrite outgrowth in LNS reflects a defective developmental process.

Effect of photoperiod variation on testes and accessory sex organs in the male blind mole rat Spalax ehrenbergi.

The blind mole rat is a seasonally breeding fossorial rodent that is perceptionally blind. This study examines the effect of photoperiod on the morphology and histology of the male mole rat reproductive system, three groups of male mole rats were maintained in the laboratory under short day (SD) conditions (9L: 15D); long day (LD) conditions (15L:9D); and constant darkness (CD), and compared to animals trapped in the field (FL). It was found that the field animals revealed higher testes and prostate gland weights, higher prostate tubuli volume (v*) and lower testes tubuli volume (v*) compared to the other three groups. Distribution of the tubuli in the testes (Vv) was low in the FL group compared to the SD and LD groups but still higher than in the CD group. Distribution of lumen in the testes (Vv) was higher in the CD group in comparison to the other three groups. Distribution of interstitial tissue in the testes (Vv) was higher in the FL group than in the other three groups. Electrolytes and elements secreted from the prostate gland did not differ among the four groups. In the FL group distribution of the tubuli (Vv) in the prostate gland was low and lumen ratio (Vv) was high compared to the other three groups. Distribution of connective tissue in the prostate gland did not differ among all four groups. Testosterone levels and total sperm count was highest in the FL group. Sperm production was noted in all groups; however spermatid and spermatozoa cell production was higher in the FL group. This study shows that photoperiod could be important in initiating timing in the breeding season but that certain other conditions which are absent in the laboratory appear to be responsible for successful breeding in the field.

Histopathology of the inferior turbinate with compensatory hypertrophy in patients with deviated nasal septum.

OBJECTIVE: To measure the dimensions, composition, and possible structural and/or histopathological changes of the compensatory hypertrophic inferior turbinate in patients with deviated nasal septum. STUDY DESIGN: A prospective, nonrandomized, and morphometric study. METHODS: Nineteen patients with deviated nasal septum and compensatory hypertrophy of the inferior turbinate in the contralateral nasal cavity underwent surgery for correction of nasal obstruction. Patients' specimens were compared with those of a control group consisting of 10 inferior turbinates removed at autopsy. Quantitative measurements of the inferior turbinate histological sections were carried out and included the width of the layers and morphometric calculations of the relative proportions of the soft tissue constituents. Also, qualitative study was performed to detect pathological changes. RESULTS: Of all layers, the inferior turbinate bone underwent a twofold increase in thickness and manifested the most significant expansion (P < or =.001), whereas the contribution of the mucosal layers to the inferior turbinate hypertrophy was modest. The morphometric analysis revealed a larger proportion of venous sinusoids in hypertrophic turbinates, but the difference was small and statistically insignificant. Qualitative assessment disclosed normal mucosal architecture in all inferior turbinates with compensatory hypertrophy. Eleven remained intact, while eight disclosed mild to moderate pathological changes. CONCLUSIONS: The data gathered in the present study are of importance to the decision-making process regarding turbinate surgery. The significant bone expansion and the relative minor role played by the mucosal hypertrophy would support the decision to excise the inferior turbinate bone at the time of septoplasty.

Age-related basement membrane thickening of the vocal cords in sudden infant death syndrome (SIDS).

Sudden infant death syndrome (SIDS) remains the leading cause of death in the Western world among infants between the ages of 1 month to 1 year. The diagnosis can only be established at autopsy, at which time no obvious or recognizable pathology is evident. A correlation between thickening of the basement membrane of the true vocal cords and the victim's age was observed in all 51 larynges examined, whereas no such finding was detected in 82 larynges of infants who died of other causes. Thus, the data support the authors' previous morphological results suggesting the use of basement membrane thickening as a marker of positive diagnosis of SIDS at autopsy. The possibility that an immune process may be associated with this syndrome merits further investigation and could prove to be of great importance.

Characteristics of palatal wound healing in desalivated rats.

The healing of excisional wounds in the palate of desalivated rats was evaluated. Experimental rats became desalivated after extirpation of the submandibular and sublingual glands and ligation of the parotid ducts. Small or large circular wounds, 3 or 5 mm in diameter, were produced in the palate. The wound area, area of inflammation, area of connective tissue formation and the number of myofibroblasts were determined at 0, 3, 7, 14, 21 and 28 days after surgery. The area of the small wound (3 mm) was similar in experimental and control groups; however, the area of the large wound (5 mm) was greater in the experimental group (p < 0.05-0.01). The area of inflammation was greater in the experimental group with small or large wounds (p < 0.05-0.01). Connective tissue formation was less (p < 0.01) in desalivated rats with a small wound at day 14 and with a large wound at days 21 and 28. There were fewer myofibroblasts in the large wound of desalivated rats (p < 0.01) than in controls between days 3 and 14. The results indicate that palatal wound healing is delayed in desalivated rats and that larger wounds are more sensitive to desalivation than smaller wounds.

Unusual renal deposit in mixed connective tissue disease.

We describe a patient with clinical signs of mixed connective tissue disease who developed nephrotic syndrome. The kidney biopsy revealed glomerular and vascular deposits that stained positive with Congo red and showed a green birefringence. The Congo red positivity became negative in sections treated with potassium permanganate. Peroxidase-antiperoxidase staining with anti-AA antibodies was strongly positive. Ultrastructurally, although the deposits were similar to amyloid, they were about twice the size of amyloid fibrils. To our knowledge, the deposition of an amyloidlike material that shows the histochemical and immunohistochemical features of amyloid AA but is lacking the distinctive ultrastructural characteristics of amyloid fibrils has not been described.

Histochemical characterization of collagen fibers in fibrous overgrowth (irritation fibroma) of the oral mucosa: effect of age and duration of lesion.

In a study of 43 specimens of oral mucosa irritation fibroma, polarization colours of collagen thin (0.8 microm) and thick (1.6-2.4 microm) fibers were recorded in formalin-fixed and paraffin-embedded sections stained with Picrosirius red. Examination of polarization colours of both the 'thin' and 'thick' collagen fibers revealed an increase of yellowish-orange and orange fibers as a function of age in patients over 30 years old (P < 0.05 only in thick fibers). When the polarization colours of thin and thick collagen fibers were recorded as a function of duration of the lesion, there was an increase in the number of yellowish-orange and orange fibers and a decrease in blue-green and green fibers in both thin (P < 0.1) and thick (P < 0.05) populations as the lesion matured. These findings show that increments in both the patient's age and the duration of the lesions increase the amount of collagen fibers which exhibit yellowish-orange and orange polarization colours indicating tighter packing and better alignment of the microfibrils, similar to normal mature collagen. These differences may have an effect on the timing of the surgical excision.