Factors affecting the detection of enteroviruses in cerebrospinal fluid with coxsackievirus B3 and poliovirus 1 cDNA probes.

Enteroviruses are common pathogens of meningitis and encephalitis, and infections are often difficult to distinguish clinically from bacterial and herpetic infections of the central nervous system. An array of enteroviruses added to cerebrospinal fluid in reconstruction experiments were detected by a dot hybridization assay. Optimal handling and processing conditions for infected cerebrospinal fluid were established, and the effect on the hybridization reaction of humoral and cellular components of the inflammatory response was determined. Six hybridization probes, derived from poliovirus 1 and coxsackievirus B3, were then tested, singly and in combinations, to optimize the sensitivity and spectrum of the assay. Implications for enteroviral taxonomy based on these experiments are discussed.     

Enterotoxin and cytotoxin production by enteroinvasive Escherichia coli.

It has long been suspected that besides their ability to invade enterocytes, enteroinvasive Escherichia coli (EIEC) strains have the ability to elaborate an enterotoxin. We tested 35 EIEC strains for cytotoxins and 9 (1 per serogroup) for enterotoxins. All 35 strains exhibited low levels of Vero cell cytotoxins that are immunologically and genetically distinct from Shiga-like toxin I or II of enterohemorrhagic E. coli. Sterile supernatants and cell lysates of two EIEC strains were tested in rabbit ileal loops, and both stimulated moderate fluid accumulation (circa 0.5 ml/cm) without tissue damage; secretory activity was confirmed in Ussing chambers, where these two strains and the seven others tested significantly increased short circuit current without altering tissue conductance. Curing the 140-MDa invasiveness plasmid from an EIEC strain did not diminish enterotoxin production. Culture in minimal Fe2+ medium is necessary to detect expression of the enterotoxin which is circa 68 to 80 kDa in size and is distinct from the EIEC cytotoxin.     

Osteogenesis imperfecta lethal in infancy: Case report and scanning electron microscopic studies of the deciduous teeth

Radiologic evaluation of the skeleton and scanning electron microscopic studies of the teeth were performed on an infant boy with a lethal osteogenesis imperfecta (OI) syndrome who died at 10 mo of pneumonia. The skeletal findings included ribs that were focally expanded by fracture calluses, flat vertebral bodies, and wide limb bones. On fractured tooth surfaces, the enamel and dentin were normal as was the dentin calcification front. Although microscopic abnormalities have been noted in teeth from previously reported infants with lethal OI, a few studies also report infants with normal teeth. These differences in dental findings may indicate heterogeneity in OI lethal in infancy. Results of our study indicate that, until the primary biochemical defects in the OI syndromes are elucidated, examination of teeth from other infants with lethal OI and detailed evaluation of other clinical and skeletal features will aid in delineating heterogeneity and variation in expression in lethal OI.     

COVID-19 prevalence and mortality in longer-term care facilities

European Journal of Epidemiology - This essay considers the factors that have contributed to very high COVID-19 mortality in longer-term care facilities (LTCFs). We compare the demographic...     

Bioethics for clinicians: 23. Disclosure of medical error

ADVERSE EVENTS AND MEDICAL ERRORS ARE NOT UNCOMMON. In this article we review the literature on such events and discuss the ethical, legal and practical aspects of whether and how they should be disclosed to patients. Ethics, professional policy and the law, as well as the relevant empirical literature, suggest that timely and candid disclosure should be standard practice. Candour about error may lessen, rather than increase, the medicolegal liability of the health care professionals and may help to alleviate the patient's concerns. Guidelines for disclosure to patients, and their families if necessary, are proposed.     

Hypertrophic mononeuritis clinically presenting with painful legs and moving toes

A 40-year-old woman presented with progressive lower leg pain and spontaneous toe movement. The EMG showed a posterior tibial nerve mononeuropathy and continuous myokymic discharges in posterior tibial-innervated muscles. The MRI revealed a markedly enlarged posterior tibial nerve. Toe movements and myokymia were unaffected by the proximal transection of the lesion but ceased abruptly when the distal end of the fusiform "tumor" was resected, suggesting that spontaneous electrical foci may have been located along the nerve lesion. The markedly enlarged nerve segment contained edematous, swollen fascicles with marked Schwann cell onion-bulb lesions and angiocentric, lymphocytic, and lymphofollicular infiltration. This nerve lesion is an example of a newly recognized entity called hypertrophic mononeuritis.     

Mechanisms of optic neuropathy

Retinal ganglion cell death is the final common pathway of all human optic neuropathies. An understanding of how these cells die, either at the cell body or after axonal injury, may allow development of strategies for rescuing these cells and therefore ameliorating optic nerve disease.