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Asymptomatic blood donors with persistent HBs antigenaemia have a variety of histological lesions in the liver, and serial biopsies indicate that, in some, these lesions may progress. The immunoperoxidase technique was found to be a sensitive method for the histological demonstration of HBsAg and HBcAg. Livers showing minor histological changes contained more HBsAg than those with active lesions and there appears to be an inverse relationship between the amount of HBsAg in the liver and the severity of the histological damage. In the carriers who had more than one biopsy, the presence of stainable HBsAg, irrespective of the initial histological diagnosis, was associated with a greater likelihood of progression of the histological lesion. HBcAg was found only in the hepatocyte nuclei of carriers with chronic aggressive and chronic persistent hepatitis. [ABSTRACT FROM PUBLISHER]

The degree of inflammation in the trachea, bronchi, and lungs of 139 cot deaths has been analysed and each case allocated to one of four groups. In group I the changes were considered to be serious enough to have caused death, while group II cases showed similar abnormalities but of a less severe nature, and in this group there was some doubt as to whether they were a significant cause of death. Group III lesions were very minor in type and were not considered to be serious enough to have resulted in the death of the child. There was a good correlation between the degree of inflammation in the respiratory tract, and whether or not bacteria of any type were grown. The great majority of the bacterial pathogens were isolated from the first two groups. Respiratory viruses were isolated from three of the four cases of acute bronchiolitis included in group I, and also from a group II case which showed considerable bronchiolar inflammation. One-third of the cases with minor inflammation in the lung parenchyma (group III) showed some evidence of recent virus infection. [ABSTRACT FROM PUBLISHER]

Presents letters to the 'British Medical Journal.' Misdiagnosis of amoebiasis; Sexual pressures in children; Health Service plans on medical education.

Presents a global correspondence on medicine. Laparoscopic complications; Distinction between good and bad medical advice by television viewers; Consistency of the alterations in serum immunoglobulin levels in herpes virus infections.

Initial liver biopsies from asymptomatic HBs antigen positive blood donors showed a range of histological abnormalities ranging from minor parenchymal lesions to cirrhosis. Twenty of these have now been followed up for periods of up to four years and during that time have had at least two liver biopsies. Throughout the period of study all the donors have remained carriers of HBs Ag, and there was no significant variation in the titers of antigen or the electron microscopic appearances of the serum in individual donors. The histological appearances of subsequent liver biopsies were not always the same as those seen initially, and while there appeared to be some improvement in three cases, there were nine in which the histological appearances were worse. [ABSTRACT FROM PUBLISHER]

The sera of 36 blood donors who are established HBsAg carriers were examined with the electron microscope. The findings were correlated with the histological and electronoptic appearances of the liver and the titre and subtype of the antigen. Antigen-antibody complexes could not be detected. Dane particles constituted 2 percent or more of the total particle count in five of the 36 sera, including three sera from five carriers with chronic aggressive hepatitis and two sera from 11 carriers with chronic persistent hepatitis. In sera from carriers with normal histology or the minimal histological lesion of focal parenchymal necrosis they were detected very infrequently or not at all. Three biopsies revealed intranuclear inclusions when examined electronoptically and the corresponding sera all contained greater than 2 percent Dane particles. Where greater than 2 percent Dane particles were seen the antigen titre tended to be high. The predominant subtype was ad. There was no correlation between the number of Dane particles and the antigen subtype nor between subtype and histology. [ABSTRACT FROM PUBLISHER]

Aim: This work describes the validation of an in-house extraction free real-time polymerase chain reaction (PCR) for the detection of Group A Streptococcus (GAS) in throat swabs collected in gel amies., Method: Throat swabs received by the laboratory were prospectively tested by routine bacterial culture and an in-house PCR assay targeting the GAS SpeB gene with a multiplexed RNaseP internal control. Samples with discrepant culture/PCR results had additional testing using the commercial Xpert Group A Strep PCR assay (Cepheid). Post introduction of the in-house GAS PCR the comparative laboratory turn-around time between PCR and historic culture results was determined., Results: Of the 1,093 throat swabs included in the final analysis, GAS was detected by culture and GAS PCR in 262 (24.0%) and 319 (29.2%) respectively. The overall, positive and negative agreement of the GAS PCR with culture was 94.2%, 98.9% and 92.8% respectively. Of the 63 discordant samples, one (33.3%) of three culture positive/in-house PCR negative samples and 56 (93.3%) of 60 culture negative/in-house PCR positive samples were GAS positive on the Xpert Group A Strep assay. Median turn-around time from laboratory receipt to result decreased from 44 to 16 hours with the introduction of the GAS PCR into routine practice. Forty-five percent of samples came from European patients and 25% from persons aged over 30 years, suggesting over-testing in persons at low risk of GAS pharyngitis complications., Conclusion: The in-house GAS PCR provided greater and faster detection of GAS from throat swabs compared to culture. However, throat swabbing for GAS needs to be better targeted to those populations at high risk of post-GAS pharyngitis complications., Competing Interests: Nil., (© PMA.)

Communication between cells is largely orchestrated by proteins on the cell surface, which allow information transfer across the cell membrane. Super-resolution and single-molecule visualization of these proteins can be achieved by genetically grafting HTP (HaloTag Protein) into the protein of interest followed by brief incubation of cells with a dye-HTL (dye-linked HaloTag Ligand). This approach allows for use of cutting-edge fluorophores optimized for specific optical techniques or a cell-impermeable dye-HTL to selectively label surface proteins without labeling intracellular copies. However, these two goals often conflict, as many high-performing dyes exhibit membrane permeability. Traditional methods to eliminate cell permeability face synthetic bottlenecks and risk altering photophysical properties. Here we report that dye-HTL reagents can be made cell-impermeable by inserting a charged sulfonate directly into the HTL, leaving the dye moiety unperturbed. This simple, one-step method requires no purification and is compatible with both the original HTL and second-generation HTL.2, the latter offering accelerated labeling. We validate such compounds, termed dye-SHTL ('dye shuttle') conjugates, in live cells via widefield microscopy, demonstrating exclusive membrane staining of extracellular HTP fusion proteins. In transduced primary hippocampal neurons, we label mGluR2, a neuromodulatory G protein-coupled receptor (GPCR), with dyes optimized for stimulated emission by depletion (STED) super-resolution microscopy, allowing unprecedented accuracy in distinguishing surface and receptors from those in internal compartments of the presynaptic terminal, important in neural communication. This approach offers broad utility for surface-specific protein labelling., Competing Interests: COMPETING INTERESTS NL is a member of the scientific advisory board of Trace Neuroscience. MRT and BCS are on patent applications describing HTL.2. All other authors declare no competing interests.

Cerebrospinal fluid (CSF) contains a tightly regulated immune system. However, knowledge is lacking about how CSF immunity is altered with aging or neurodegenerative disease. Here, we performed single-cell RNA sequencing on CSF from 45 cognitively normal subjects ranging from 54 to 82 years old. We uncovered an upregulation of lipid transport genes in monocytes with age. We then compared this cohort with 14 cognitively impaired subjects. In cognitively impaired subjects, downregulation of lipid transport genes in monocytes occurred concomitantly with altered cytokine signaling to CD8 T cells. Clonal CD8 T effector memory cells upregulated C-X-C motif chemokine receptor 6 (CXCR6) in cognitively impaired subjects. The CXCR6 ligand, C-X-C motif chemokine ligand 16 (CXCL16), was elevated in the CSF of cognitively impaired subjects, suggesting CXCL16-CXCR6 signaling as a mechanism for antigen-specific T cell entry into the brain. Cumulatively, these results reveal cerebrospinal fluid immune dysregulation during healthy brain aging and cognitive impairment., Competing Interests: Declaration of interests T.W.-C. and D.G. are co-inventors on a patent related to this work. Patent US-2022-0170908-A1 is for compositions and methods for measuring T cell markers associated with AD., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Lysosome dysfunction is a shared feature of rare lysosomal storage diseases and common age-related neurodegenerative diseases. Microglia, the brain-resident macrophages, are particularly vulnerable to lysosome dysfunction because of the phagocytic stress of clearing dying neurons, myelin, and debris. CD22 is a negative regulator of microglial homeostasis in the aging mouse brain, and soluble CD22 (sCD22) is increased in the cerebrospinal fluid of patients with Niemann-Pick type C disease (NPC). However, the role of CD22 in the human brain remains unknown. In contrast to previous findings in mice, here, we show that CD22 is expressed by oligodendrocytes in the human brain and binds to sialic acid–dependent ligands on microglia. Using unbiased genetic and proteomic screens, we identify insulin-like growth factor 2 receptor (IGF2R) as the binding partner of sCD22 on human myeloid cells. Targeted truncation of IGF2R revealed that sCD22 docks near critical mannose 6-phosphate–binding domains, where it disrupts lysosomal protein trafficking. Interfering with the sCD22-IGF2R interaction using CD22 blocking antibodies ameliorated lysosome dysfunction in human NPC1 mutant induced pluripotent stem cell–derived microglia-like cells without harming oligodendrocytes in vitro. These findings reinforce the differences between mouse and human microglia and provide a candidate microglia-directed immunotherapeutic to treat NPC.

Recent studies indicate that the adaptive immune system plays a role in Lewy body dementia (LBD). However, the mechanism regulating T cell brain homing in LBD is unknown. Here, we observed T cells adjacent to Lewy bodies and dopaminergic neurons in postmortem LBD brains. Single-cell RNA sequencing of cerebrospinal fluid (CSF) identified up-regulated expression of C-X-C motif chemokine receptor 4 ( CXCR4 ) in CD4 + T cells in LBD. CSF protein levels of the CXCR4 ligand, C-X-C motif chemokine ligand 12 (CXCL12), were associated with neuroaxonal damage in LBD. Furthermore, we observed clonal expansion and up-regulated interleukin 17A expression by CD4 + T cells stimulated with a phosphorylated α-synuclein epitope. Thus, CXCR4-CXCL12 signaling may represent a mechanistic target for inhibiting pathological interleukin-17–producing T cell trafficking in LBD.

AB Granville was a pioneer obstetrician and gynaecologic surgeon who performed the world's first myomectomy and the first ovariotomy in England. He also performed the first scientific autopsy of an Egyptian mummy, discovering the oldest known ovarian tumour. He thought it was malignant and caused her death from 'ovarian dropsy'. This study reveals the tumour to be a benign cystadenoma. Further analysis indicates she died from terminal pneumonia from tuberculosis., (© The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.)

This study was conducted to develop tests for evaluation of uri ne concentratingability, urine acidification ability, an dglomerular filtration rate in cynomolgus macaques. In female cynomolgus macaques, baseline urine specific gravity ranged from 1.005 to 1.031, and urine osmolality ranged from 182 to 1081 mOsm/kg. A dose of 0.4 microg/kg desmopressin acetate resulted in a urine specific gravity that ranged from 1.019 to 1.043 and an osmolality that ranged from 432 to 1298 mOsm/kg. Desmopressin acetate administration increased urine specific gravity and osmolality in each animal evaluated. Baseline urine pH in these animals ranged from 6.4 to 8.2. A dose of orally administered ammonium chloride (0.1 g/kg) resulted in a urine pH that ranges from 4.1 to 7.1. Ammonium chloride administration decreased urine pH in each animal tested. Evaluation of glomerular filtration rate was accomplished through urine collection and timed blood and urine samples after oral hydration with 0.45% sodium chloride. Blood samples were analyzed for creatinine, osmolality, sodium, potassium, and chloride. Urine samples were analyzed for volume, creatinine, osmolality, sodium, potassium, and chloride. Creatinine clearance, osmolality clearance, and electrolyte fractional clearance were calculated from the values. Osmolality clearance ranged from 0.03 to 0.07 ml/kg/min, creatinine clearance ranged from 1.84 to 2.53 ml/kg/min, fractional excretion of sodium ranged from 0.17% to 0.77%, fractional excretion of potassium ranged from 4.46% to 19.87%, and fractional excretion of chloride ranged from 0.25% to 1.08%. The response to desmopressin acetate and ammonium chloride and the osmolality, creatinine concentration, and fractional electrolyte excretion were consistent in individual animals with repeat testing. No adverse events were associated with the tests. The results of these tests are consistent with repeat testing in individual animals. These tests likely can be used for clinical assessment of renal function in cynomolgus macaques or for collection of experimental data.

Phospholipase D (PLD) activity in human embryonic kidney (HEK) cells is stimulated by phorbol-ester-activated protein kinase C (PKC) and by membrane receptors, the latter apparently acting via the GTP-binding proteins, ADP-ribosylation factor (ARF) and Rho. In the present study, performed in cell-free preparations, we have characterized and compared the regulation of HEK cell PLD activity by the stable GTP analogue, guanosine 5'-O-[gamma-thio]triphosphate (GTP[S]), and the phorbol ester, phorbol 12-myristate 13-acetate (PMA). In digitonin-permeabilized HEK cells, prelabeled with [3H]oleic acid, GTP[S] and PMA caused an approximately threefold concentration-dependent increase in the formation of [3H]phosphatidylethanol, measured in the presence of ethanol. Neomycin, which is known to complex with the PLD cofactor, phosphatidylinositol 4,5-bisphosphate, decreased basal and GTP[S]- or PMA-stimulated PLD activities with similar sensitivity. GDP and its analogue, guanosine 5'-O-[beta-thio]diphosphate, inhibited the stimulatory effect of GTP[S], whereas the PMA response was prevented by the nonselective PKC inhibitor, staurosporine, but not vice versa. PLD stimulation by GTP[S], but not by PMA, was markedly reduced upon cytosol depletion and reconstituted by purified recombinant ARF1. In HEK cell membranes, addition of purified recombinant ARNO, a guanine-nucleotide-exchange factor for ARF1. potentiated the GTP[S]-stimulated PLD activity. PLD stimulation by PMA in HEK cell membranes required MgATP and was largely prevented by the selective PKC inhibitors Goe 6976 and bisindolylmaleimide I. Immunoblot analysis demonstrated that both conventional PKC (alpha, beta, gamma) and atypical PKC isozymes (zeta, tau) were present in HEK cell membranes. The results indicate that phorbol ester stimulation of PLD activity in HEK cells apparently occurs by a phosphorylation-dependent mechanism involving membrane-associated PKC isozymes but not ARF proteins, the major targets of GTP[S]' action.

The action of the radioprotector WR 10 65 on regional function of the left ventricular muscle in ischemic injured and reperfused rat heart was investigated employing a new fiber optic based method for determination of segment shortening. In anesthetized rats exposed to regional myocardial ischemia by ligation of the left anterior descending coronary artery for 60 minutes followed by 60 minutes of reperfusion WR 10 65 applicated in a dosage of 1 mM/kg body weight intraperitoneally 30 minutes prior to ischemia induced an improvement of post ischemic recovery of segment shortening from 31% of pre-ischemic values in untreated animals to 64.6%. Because only moderate alterations in global functional parameters compared to control group were found in WR 10 65 treated animals, it is presumed that the observed influence on regional myocardial function is less due to changes in cardiac load than to the radical scavenger activity of the tested agent. A possible contribution of hypoxic and hypocalcemic activity of the substance remains to elucidate.