PubMed Health⌕ Search

Biomedical subjects

J Mathews

Publications and source records attributed to J Mathews.

At least 73 records · Page 4Linked to original sources

Liver function tests. A study in patients with imaging-demonstrated metastases.

Thirty-eight consecutive patients with liver scan evidence of hepatic metastases (and confirmation by other modalities) had blood levels of lactate dehydrogenase and alkaline phosphatase performed within two weeks. In 38% of the patients with small liver metastases, both alkaline phosphatase and lactate dehydrogenase were in the normal range. Even with large metastases present (one or more lesions over 2.5 cm in diameter), 19% of the patients had both enzyme tests within the normal range. Despite the lower cost of these enzyme assays, they failed to detect hepatic metastases in an appreciable portion of our patients.

Alkaline Phosphatase↗

Rapid response of intrasplenic lesions to steroids in non-Hodgkin's lymphoma.

A 70 year old woman had a [99mTc]sulfur colloid liver/spleen scan that showed splenomegaly and multiple intrasplenic defects. The lesions failed to concentrate radiogallium. Thirteen days later, after being on steroid therapy, the spleen had decreased in size and the lesions were only barely apparent. The intrasplenic process, due to non-Hodgkin's lymphoma, was thus markedly sensitive to steroids. It is uncertain if such rapid regression can be employed as a prognostic indicator in non-Hodgkin's lymphoma and suggests the need for further monitoring. The differential diagnosis of the rapid response of intrasplenic lesions to steroids is a limited one, and likely includes sarcoidosis.

Aged↗

Pulmonary ventilation/perfusion and reverse mismatches in an infant.

A male infant, with bronchopulmonary dysplasia and ventilator dependence, had lung ventilation (Xe-133 gas) and perfusion (Tc-99m MAA) imaging performed. The examination revealed a region that was ventilated but not perfused (mismatch) and a separate area that was perfused but not ventilated (reverse mismatch). The basis of both abnormalities is suspected to be related to bronchopulmonary dysplasia, atelectasis and/or mechanical ventilation. Ventilation/perfusion mismatches and reverse mismatches can occur in the same patient.

Bronchopulmonary Dysplasia↗

Infrabladder "cup defect" following prostatectomy: recognition on bone scintigram.

Seventeen bone scintigrams, made after prostatectomy for proven or suspected carcinoma, showed a "cup defect" below the bladder. This defect was likely related to the volume of tissue removed at the time of transurethral prostatectomy. In two cases, the defect was not present on images made before prostatectomy but was clearly seen after the operation. The time of persistence of the "cup defect" is discussed, as well as the differential diagnosis of the finding.

Bone and Bones↗

Prospective evaluation of syncope.

One hundred seventy patients with syncope presenting to an emergency department were studied prospectively. A checklist was used to supplement the physician's history and physical to ensure adequate recording of potentially useful data. Follow-up data were available in 89% of patients with a mean follow-up period of 6.2 months. Patients were categorized by presumed etiology using specific criteria. Typical vasovagal syncope occurred in 37.1% of patients. Other etiologies included first seizure (8.8%), orthostasis (7.6%), cardiac (4.1%), micturition (2.4%), hypoglycemia (1.8%), and psychogenic (0.6%). Syncope of unknown etiology accounted for 37.6% of the patients. The estimated duration of warning period was significantly shorter in patients with cardiac syncope compared to patients with vasovagal syncope. The yield of laboratory tests was low with the exception of the serum bicarbonate, which was decreased in 70% of our seizure patients. Recommendations regarding initial evaluation and admission are discussed.

Adolescent↗

Drugs that may exacerbate myasthenia gravis.

Myasthenia gravis is an uncommon disease. The emergency physician should be cautious when prescribing medications to myasthenics for problems not related to myasthenia gravis. We have discussed some of those agents (Figure 3) that are recognized to cause exacerbation of MG or that may have the potential to exacerbate MG. We recommend that management of any medical or surgical problem of the myasthenic be done in consultation with a managing neurologist, and that either early follow-up or admission is necessary when these agents are used in the patient with myasthenia gravis.

Anti-Bacterial Agents↗

Antibiotic-induced modification of Bacteroides fragilis and its susceptibility to phagocytosis by human polymorphonuclear leukocytes.

Bacteroides fragilis grown in the presence of sub-inhibitory concentrations of clindamycin was shown to be altered its degree of encapsulation and susceptibility to phagocytosis by human polymorphonuclear leukocytes. Little polysaccharide capsule could be demonstrated either by light or transmission electron microscopy when the bacteria were grown anaerobically for four hours in the presence of 1/2 MIC of clindamycin. Such clindamycin-grown cells could be opsonized by normal human serum, and although less complement was consumed in the process, were more effectively taken up by the leukocytes than bacteria grown in the absence of the drug (45% versus 24%). It was also shown that drug treatment caused significant cellular leakage in the presence of serum, the 3H-label appearing extracellularly. In addition there was greater loss of viability of the bacterial cells grown in the presence of the drug and subsequently exposed to the leukocytes for 60 min.

Bacteroides fragilis↗

Potentiation of opsonization and phagocytosis of Streptococcus pyogenes following growth in the presence of clindamycin.

Streptococcus pyogenes, bearing M-protein on its surface, resists opsonization by normal human serum and subsequent phagocytosis by human polymorphonuclear leukocytes. Previous studies have shown that M-protein positive organisms are poorly opsonized by the alternate pathway of complement. In an attempt to define further the role of the surface components of S. pyogenes in this process, we examined the ability of clindamycin, an antibiotic that inhibits protein biosynthesis, to alter bacterial opsonization. An M-protein positive strain of S. pyogenes was grown in varying concentrations of clindamycin at levels lower than those which inhibited growth, i.e., at levels less than the minimal inhibitory concentration. These bacteria were incubated with purified human polymorphonuclear leukocytes and peripheral blood monocytes. Significant enhancement of bacterial opsonization, phagocytosis, and killing resulted. Measurement of complement consumption and binding of the third component of complement (C3) onto the bacterial surface demonstrated that organisms grown in the presence of clindamycin activated complement more readily and fixed more C3 on their surface. Electron microscopy revealed the probable basis for these findings. Streptococci exposed to clindamycin during growth were largely denuded of surface "fuzz," the hairlike structures bearing M-protein. We conclude that the incorporation of clindamycin at concentrations that fail to inhibit growth of S. pyogenes nevertheless causes significant changes in the capacity of these bacteria to resist opsonization by serum complement. These findings support the hypothesis that M-protein inhibits bacterial opsonization by interfering with effective complement activation on the bacterial surface.

Antigens, Bacterial↗

Effect of 1-(2,4-dichlorobenzyl)-indazole-3-carboxylic acid on sperm tails in rhesus monkeys.

Large numbers of spermatozoa with bent or coiled tails were found in the ejaculates of rhesus monkeys treated with 1-(2,4-dichlorobenzyl-indazole-3-carboxylic acid (DICA) (50 or 500 mg/kg for various periods). The defect appeared only in spermatozoa in the cauda epididymidis and consisted of axoneme disarrangement and loss of the fibre doublets. The coil was completely enclosed in a membrane.

Animals↗

Pathogenesis of herpes simplex virus types 1 and 2 in mice after various routes of inoculation.

The pathogenesis of herpes simplex virus (HSV) types 1 and 2 was compared after inoculation of mice by different routes. Intravaginal inoculation of HSV-1 and HSV-2 produced a local infection, with virus recovery from the vagina through 5 days. Virus was recovered from the spinal cords 4 to 5 days after inoculation but not from liver, kidney, lung, spleen, or blood. Intravenous or intraperitoneal inoculation of HSV-2 produced a focal necrotic hepatitis similar to that described previously (S. C. Mogenson, B. Teisner, and H.K. Andersen, 1974). The viral etiology of the liver lesions was confirmed by virus isolation (through 4 days) and electron microscopy. No evidence of infection of the kidney, lung, blood, or spleen was observed, although virus was isolated from spinal cord homogenates 7 days after inoculation. HSV-1 inoculation by the intraperitoneal or intravenous route resulted in virus isolation from the kidney during the 7-day harvest period, without producing overt pathological changes. Virus was isolated from spinal cord homogenates 2 to 3 days after HSV-1 inoculation but not from homogenates prepared from spleen, lung, or blood. Increases in serum transaminase activity were observed after systemic (intravenous) inoculation of HSV-2 but not after HSV-1 inoculation.

Alanine Transaminase↗