COVID-19-Associated Bifacial Weakness with Paresthesia Subtype of Guillain-Barré Syndrome.

We report a case of bifacial weakness with paresthesia, a recognized Guillain-Barré syndrome subtype characterized by rapidly progressive facial weakness and paresthesia without ataxia or other cranial neuropathies, which was temporally associated with antecedent coronavirus 2019 (COVID-19). This case highlights a potentially novel but critically important neurologic association of the COVID-19 disease process. Herein, we detail the clinicoradiologic work-up and diagnosis, clinical course, and multidisciplinary medical management of this patient with COVID-19. This case is illustrative of the increasingly recognized but potentially underreported neurologic manifestations of COVID-19, which must be considered and further investigated in this pandemic disease.

Development of the Logical Observation Identifier Names and Codes (LOINC) vocabulary.

The LOINC (Logical Observation Identifier Names and Codes) vocabulary is a set of more than 10,000 names and codes developed for use as observation identifiers in standardized messages exchanged between clinical computer systems. The goal of the study was to create universal names and codes for clinical observations that could be used by all clinical information systems. The LOINC names are structured to facilitate rapid matching, either automated or manual, between local vocabularies and the universal LOINC codes. If LOINC codes are used in clinical messages, each system participating in data exchange needs to match its local vocabulary to the standard vocabulary only once. This will reduce both the time and cost of implementing standardized interfaces. The history of the development of the LOINC vocabulary and the methodology used in its creation are described.

Assessment and predictability of renal function in spinal cord injury patients.

Creatinine clearance values were determined by duplicate urine collections in 18 patients with spinal cord injury, cerebrovascular accident, or multiple sclerosis. Measured creatinine clearance values were compared with estimates predicted by a urine-free mathematical method for estimation of renal function. Measured creatinine clearance values were considerably lower than would be ordinarily expected on the basis of patient body size, age, sex, and serum creatinine. In addition, creatinine clearances calculated using the urine-free method were considerably higher than measured values, suggesting that techniques for the prediction of creatinine clearance may not be routinely applicable in patients with these conditions.

Localization of microglia in the human fetal cervical spinal cord.

Differential morphologic subtypes of microglia have been identified in the human fetal frontal cerebrum using a lectin, Ricinus communis agglutinin 1 (RCA-1), and a monoclonal antibody, EBM-11. In this report, microglia were characterized in the human fetal cervical spinal cord. RCA-1-positive microglia were ramified in the developing gray matter while in the developing white matter they had a less differentiated (ameboid) appearance. EBM-11, a monoclonal antibody that recognizes CD68 on human macrophages, and microglia labeled only ameboid-type microglia in the developing white matter. This suggests that distinct subpopulations of microglia exist, which may represent different stages in microglial development, and that CD68 may be a differentiation marker for less mature forms. Therefore, cytologically less differentiated forms of microglia appear to be associated with myelination.

Localization of morphologically distinct microglial populations in the developing human fetal brain: implications for ontogeny.

Although 70 years have elapsed since del Rio Hortega's initial description of microglia, the ontogeny of these cells remains enigmatic. In addition to the general scientific importance of clarifying this issue, a more complete characterization of microglia is dictated by their apparent pivotal role in the pathophysiology of central nervous system (CNS) disease associated with the acquired immunodeficiency syndrome (AIDS) in adults and, especially, in children. To accomplish this goal, fetal central nervous system tissue was collected at the time of elective pregnancy terminations. Coronal vibratome sections of Bouin's-fixed cerebrum were either stained with Ricinus communis agglutinin-1 (RCA-1) or analyzed by immunohistochemistry using monoclonal antibodies that recognize human tissue macrophages and microglia. By at least 13 weeks of gestation, microglia were detected in fetal brain. In the 13-18 week gestational age cerebrum, there was variability in the morphology of microglia within the developing white matter and cortex. However, there was less variability within these areas in the 19-24 week gestational age group. At all ages the greatest number of labeled cells per field was in the germinal matrix with decreasing numbers in the developing white matter and cortex. Cells in the germinal matrix were round with short processes ('ameboid microglia') while cortical cells were more ramified ('resting microglia'). These results suggest that microglia may originate in the germinal matrix rather than in the pial mesenchyme as originally hypothesized by del Rio Hortega.(ABSTRACT TRUNCATED AT 250 WORDS)

Gypsum mixtures for compensator construction.

The characteristics and properties of a new material used for the fabrication of compensators are presented. This material is a special, refined gypsum. It requires a factor of 3 less water to prepare than ordinary gypsums and as a result the attenuation properties are stable over time. The material may be used by itself or mixed with fine metal particles to increase the attenuation per unit thickness. Gypsum, gypsum + steel, and gypsum + iron were investigated. The results of attenuation measurements in narrow- and broad-beam geometries appropriate to design of clinical dose modifying compensators are presented. Practical and technical details associated with the use of these materials are given. These compounds are found to be easy to use, versatile, reliable, environmentally safe, and inexpensive. In addition, an example of their use for dose compensation is given.

Neurotransmitter distribution in the second trimester fetal human corpus striatum.

One experimental strategy that may offer hope in the neurodegenerative disorder Huntington's disease (HD) has been neural transplantation. In HD, most of the pathological changes occur in the corpus striatum. Fetal human striatal implants will most likely be the first transplant strategy attempted in clinical trials to replace lost neurons and/or prevent the degeneration of neurons destined to die. The temporal expression of neurotransmitters in the developing human corpus striatum is a key factor in determining the optimum age of transplantable tissue. To this end, an immunocytochemical analysis of various neurotransmitters was performed on second trimester human brains. Antibodies against acetylcholine, gamma-aminobutyric acid, enkephalin, neuropeptide-Y and substance P were used in ten human fetal brains ranging from 13 to 21 weeks gestation. The presence and pattern of distribution for these neurotransmitters varied in the different parts of the corpus striatum (globus pallidus, putamen, caudate nucleus). These results are compared to the already existing data for the adult human corpus striatum.

Neck needle foreign bodies: an added risk for autopsy pathologists.

The risk to pathologists of contracting diseases due to cuts or needles punctures while performing autopsies is well known. An additional risk is an accidental needle puncture due to retained needle fragments within the subcutaneous tissues or internal organs of intravenous drug addicts. We report 4 cases of drug addicted patients infected with human immunodeficiency virus who came to autopsy and had retained needle fragments within their cervical-clavicular soft tissues. The presence of retained needle fragments increases the risk to the autopsy pathologist of accidental needle puncture and exposure to disease. Because of this phenomenon, the pathologist should take precautions in addition to those currently prescribed when performing autopsies on possible drug abusers.

Sudden unexpected death in a patient with splenic sequestration and sickle cell-beta+-thalassemia syndrome.

Acute splenic sequestration crisis is a rare disorder that usually occurs in children, with sickle cell anemia, who are under the age of five years. A few cases have been described in adults with heterozygous sickle cell syndromes. Though this entity can be fatal there have been no reported cases associated with sudden death. We describe a case of sudden, unexpected death, associated with splenic sequestration, in a 29-year-old African-American man with undiagnosed sickle cell-beta-thalassemia syndrome.

Heroin body packing: three fatal cases of intestinal perforation.

Death from heroin body packing has been well described in the forensic literature. Most fatalities are due to drug leakage and consequent acute heroin toxicity. Recently, drug traffickers have become more sophisticated in their packaging, and the risk of rupture of drug packets is more remote. Though intestinal obstruction is a recognized risk of body packing, rarely has this resulted in death. We describe four cases of heroin body packing presenting to the Regional Medical Examiner Office in New Jersey. Death in three of these cases was due to intestinal obstruction, with resultant intestinal rupture and peritonitis. Toxicologic evaluation in these three cases was negative for opiates or other drugs of abuse. In one case, death was due to acute heroin toxicity, validated by toxicologic analysis. We briefly discuss the differing drug packaging found in these four cases and the ramifications of packaging as it relates to intestinal obstruction.

Upregulation of activating transcription factor 3 (ATF3) by intrinsic CNS neurons regenerating axons into peripheral nerve grafts.

The expression of the transcription factor ATF3 in the brain was examined by immunohistochemistry during axonal regeneration induced by the implantation of pieces of peripheral nerve into the thalamus of adult rats. After 3 days, ATF3 immunoreactivity was present in many cells within approximately 500 mum of the graft. In addition, ATF3-positive cell nuclei were found in the thalamic reticular nucleus (TRN) and medial geniculate nuclear complex (MGN), from which most regenerating axons originate. CNS cells with ATF3-positive nuclei were predominantly neurons and did not show signs of apoptosis. The number of ATF3-positive cells had declined by 7 days and further by 1 month after grafting when most ATF3-positive cells were found in the TRN and MGN. 14 days or more after grafting, some ATF3-positive nuclei were distorted and may have been apoptotic. In some experiments of 1 month duration, neurons which had regenerated axons to the distal ends of grafts were retrogradely labeled with DiAsp. ATF3-positive neurons in these animals were located in regions of the TRN and MGN containing retrogradely labeled neurons and the great majority were also labeled with DiAsp. SCG10 and c-Jun were found in neurons in the same regions as retrogradely labeled and ATF3-positive cells. Thus, ATF3 is transiently upregulated by injured CNS neurons, but prolonged expression is part of the pattern of gene expression associated with axonal regeneration. The co-expression of ATF3 with c-jun suggests that interactions between these transcription factors may be important for controlling the program of gene expression necessary for regeneration.

Cell wall receptor for yeast killer toxin: involvement of (1 leads to 6)-beta-D-glucan.

The linear (1 --> 6)-beta-d-glucans pustulan and luteose were effective competitive inhibitors of killer toxin action. Affinity chromatography of killer toxin on a pustulan-Sepharose column showed that toxin bound directly to a (1 --> 6)-beta-linked polysaccharide. Other polysaccharides found in yeast cell walls, including (1 --> 3)-beta-d-glucan, mannan, chitin, and glycogen, were not effective as inhibitors of toxin. Fractionation of yeast cell walls was attempted to identify the toxin receptor in sensitive Saccharomyces cerevisiae. The receptor activity was retained among the insoluble glucans in alkali-washed cells; yeast mannan and alkali-soluble glucan had little receptor activity. A minor fraction of receptor activity was removed from alkali-washed cells by hot acetic acid extraction, a procedure which solubilized some (1 --> 6)-beta-d-glucan and glycogen. The major fraction (>70%) of receptor activity remained with the acid-insoluble (1 --> 6)-beta-and (1 --> 3)-beta-glucans. Zymolyase, an endo-(1 --> 3)-beta-d-glucanase, solubilized a substantial fraction of the receptor activity in the acid-insoluble glucans. The receptor activity in yeast cell walls was periodate and (1 --> 6)-beta-d-glucanase sensitive, but was resistant to (1 --> 3)-beta-d-glucanase and alpha-amylase. The acid-soluble glucan fractions of a sensitive strain and a krel-l receptor-defective toxin-resistant mutant were examined. The krel-l strain had a reduced amount (ca. 50%) of (1 --> 6)-beta-d-glucan compared with the sensitive parent strain. A sensitive revertant of the krel-l strain regained the parental level of glucan. These results implicate (1 --> 6)-beta-d-glucan as a component of the yeast cell wall receptor for killer toxin.

Seizures caused by ingestion of composition C-4.

Composition C-4 (C-4) is a plastic explosive widely used in both military and civilian settings. Ingestion of the active ingredient, RDX (cyclonite), can cause generalized seizures. Accidental and intentional C-4 (RDX) intoxications have occurred during manufacture or in wartime. In the literature the intentional ingestion of C-4 has been reported but not verified. We present a case of intentional C-4 abuse.

Corticospinal projections from the medial wall of the hemisphere.

We injected wheat germ agglutinin conjugated to horseradish peroxidase into different segments of the spinal cord in order to examine the topographic organization of corticospinal projections from the medial wall of the hemisphere. We observed that substantial projections to the spinal cord originate not only from the supplementary motor area (SMA) in area 6, but also from 2 regions within the cingulate sulcus. The distribution of labeled neurons following tracer injections into different spinal cord segments indicates that corticospinal projections from the SMA and from the 2 cingulate regions are somatotopically organized. These findings together with other recent anatomical observations suggest that the corticospinal projections from the medial wall of the hemisphere provide the basal ganglia and limbic system with a somatotopically organized access to spinal cord mechanisms.

Binding of yeast killer toxin to a cell wall receptor on sensitive Saccharomyces cerevisiae.

35S-labeled killer toxin protein bound to cells of sensitive Saccharomyces cerevisiae S14a. Strains that were resistant to toxin through mutation in the nuclear genes kre1 kre2 bound toxin only weakly. Non-radioactive toxin competed effectively with 35S-labeled toxin for binding to S14a, but did not compete significantly in the binding to mutant kre1-1. This implied that binding to kre1-1 was nonspecific. A Scatchard analysis of the specific binding to S14a gave a linear plot, with an association constant of 2.9 x 10(6) M-1 and a receptor number of 1.1 x 10(7) per cell. Killer toxin receptors were solubilized from the cell wall by zymolyase digestion. Soluble, non-dialyzable cell wall digest from S14a competed with sensitive yeast cells for 35S-labeled toxin binding and reduced toxin-dependent killing of a sensitive strain. Wall digest from kre1-1 competed only weakly for toxin binding with sensitive cells and caused little reduction of toxin-dependent killing. Although the abundant (1.1 x 10(7) per cell) receptor appeared necessary for toxin action, as few as 2.8 x 10(4) toxin molecules were necessary to kill a sensitive cell of S14a. The kinetics killing of S14a suggested that some component was saturated with toxin at a concentration 50-fold lower than that needed to saturate the wall receptor.