Skin testing in farmers' lung disease

Intradermal skin tests with a culture filtrate antigen of Micropolyspora faeni grown on a synthetic medium were performed on patients with farmers' lung disease (FLD) and well farmers with and without antibodies to a panel of FLD antigens. Seventy-five percent of the FLD patients, 79% of the well farmers with M. faeni antibody, and 5% of well farmers without M. faeni antibody had a 2+ or greater intradermal immediate skin-test reaction. Prausnitz-Küstner (P-K) reactions were positive using serum of M. faeni immediate skin test-positive FLD patients. IgG-rich fractions from a staphylococcal protein A-Sepharose column of such serum contained the sensitizing factor whereas IgG-depleted fractions did not. M. faeni—specific IgE could not be detected in serum by a polystyrene radioimmunoassay. Positive late-onset (6-hr) skin tests occurred only in FLD patients and farmers with precipitating antibody. Biopsy specimens of the 6-hr reactions revealed a generalized dermal and perivascular polymorphonuclear infiltrate with deposits of immunoglobulin and complement about blood vessels. The skin-sensitizing factor noted in FLD patients and well farmers with antibody is not disease specific. This factor appears to be associated with the IgG-rich fraction of serum, and its role in the pathogenesis of FLD is unclear.     

Ontogenesis of the secretory immune system and innate defence factors in human parotid glands

Immunoglobulin-producing cells and epithelial expression of secretory component (SC), amylase, lysozyme (Ly) and lactoferrin (Lf) were studied by immunohistochemistry to obtain information about the development of mucosal immunity. Tissue specimens were obtained from 20 fetal and 40 postnatal parotid glands. (1) Fetal specimens. Occasional IgM- and IgA- but no IgD-, IgG- or IgE- producing cells were seen (ratios, IgM:IgA:IgD:IgG:IgE approximately 4:1:0:0:0). The IgAl subclass dominated (median 90%, range 50-95%) and these cells were mostly J-chain-positive (median 97%, range 94-98%). Only few IgA2-producing cells were seen (median 10%, range 5-50%) and they were also mostly J-chain-positive (median 99%, range 98-100%). Amylase, Ly and Lf were most prominent in early fetal life, while only small amounts of SC were present. (2) Postnatal specimens. Secretory component increased markedly along with a growing number of IgA- and IgD-producing cells (IgA:IgM:IgD:IgG:IgE approximately 4:2:1:1:0). The IgAl subclass remained predominant (median 65%, range 50-90%) although the proportion of IgA2-positive cells tended to be raised (median 35%, range 10-50%). Most IgAl (median 97%, range 67-100%) and IgA2 (median 94%, range 75-100%) cells were J-chain-positive. These features probably reflected local activation of the immune system in response to environmental factors. The amount of amylase, Ly and Lf decreased shortly after delivery, perhaps because the cellular stores were emptied by postnatal increase in secretory activity.     

偏瘫宁治疗缺血性脑血管病前后脑电地形图研究

目的:探讨脑电地形图在缺血性脑血管病疗效判断上的应用价值。方法:通过对300例缺血性脑血管病治疗前后脑电地形图改变的对比评价。结果:脑电地形图在治疗前后有明显改变。结论:脑电地形图可以做为缺血性脑血管病疗效观察的一个有效指标。     

The use of detergents and immunoperoxidase reagents for the ultrastructural demonstration of internal immunoglobulin in lymph cells.

Lymph-borne immunoblasts were fixed in dilute glutaraldehyde and then treated with saponin. This treatment made most parts of the cells permeable to ferritin, so that anti-immunoglobulin (Ig) antibodies which had been conjugated to horse radish peroxidase (HRP) had no difficulty in gaining access to Ig which thus could be demonstrated at an ultrastructural level. Best results were obtained by fixing the cells in 0.1% glutaraldehyde for 7 min and then treating them with a 1% solution of saponin for 100 min at 55 degrees C before exposing them to the Ig-HRP conjugate. The method yielded reproducible results and although it causes a small amount of ultrastructural damage, it may be of value in detecting a variety of intracellular antigens.     

Prognostic factors determining response to antidepressant drugs in psychiatric out-patients and general practice

The outcome of antidepressant drug treatment was measured in 200 patients, 145 seen in psychiatric out-patient clinics and 55 in general practice, after 4 weeks of therapy. The results of the 200 patients taken together suggested that prognosis was largely determined by factors dependent on the natural history of the disorder and that clinical symptoms were unimportant, but when the results for patients in each drug group were analysed separately symptoms were more important than natural history factors. We conclude that clinical symptoms are only important predictors of response to antidepressant drugs when the patients studied are homogeneous with regard to natural history factors, particularly duration of illness.     

Karyotyping chromosomes by electron microscopy. Condensation-inhibition of G bands in human and Chinese hamster chromosomes by a BrdU-Hoechst 33258 treatment

A BrdU-Hoechst 33258 treatment of living cells, which selectively induced condensation-inhibition of G-band chromatin in human and Chinese hamster chromosomes, is presented. As a consequence mitotic chromosomes showed high resolution R-banding patterns when examined by light and electron microscopy. Besides each whole chromosome identification, this procedure also permitted the electron microscopic study of specific structures, such as satellites, secondary constrictions, telomeres, centromeres, as well as G and R bands, some of them not visible by light microscopy. We have also observed that the chromatin of G and R bands behave as blocks of chromatin condensation and that G-band chromatin develops condensation along G₂. Under the BrdU-Hoechst 33258 treatment, chromatin fibers seem to invert their spontaneous pattern of condensation within the chromosomes.     

Mechanism of disturbances of energy formation in acute ischemia of the liver

Respiration of rat liver mitochondria after the addition of ischemic toxin to the incubation medium was compared with respiration of mitochondria isolated from ischemic rat liver. The changes in respiration in both cases could be prevented by preliminary addition of dithiothreitol and reduced by subsequent addition of cytochrome c or dithiothreitol to the incubation medium. The similarity between the mechanisms of disturbance of energy formation is postulated.Laboratory of Transplantation of Organs and Tissues, Academy of Medical Sciences of the USSR, Moscow. Institute of Clinical and Experimental Medicine, Academy of Medical Sciences of the USSR, Siberian Branch, Novosibirsk. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Kovanov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 9, pp. 301–303, September, 1977.     

Regional cerebral blood flow after occlusion of the middle cerebral artery

Occlusions of the middle cerebral artery (MCA) are mostly of embolic origin (appr. 80%) and give rise to about one third of all ischemic strokes, most of these being major strokes. MCA occlusions lasting for less than 1/2 h are tolerated without occurrence of permanent tissue damage. Occlusions lasting between 1/2 h to 4-8 h lead to permanent tissue damage and neurological deficits that are proportional to the duration of occlusion. Maximal tissue damage is obtained after 4-8 h occlusion. A cerebral blood flow of 8-23 ml/100 gr/min is sufficient for cellular viability but insufficient for normal tissue function ("ischemic penumbra"). Cellular function is completely abolished in the interval 8-16 ml/100 gr/min and flow at that level is tolerated only for 1-3 h before neuronal death ensues. In the interval 18-23 ml/100 gr/min there is some functional activity although it is reduced. Experimental and clinical evidence suggests that flow in this interval may be tolerated for several days, months or even longer ("chronic ischemic penumbra"). After MCA occlusion the blood flow falls below 8 ml/100 gr/min in most cases and permanent MCA occlusion always leads to relatively large areas of frank infarction. The ischemic infarcts may be surrounded by collaterally perfused areas where the blood flow is pressure-dependent (impaired autoregulation) and quite commonly insufficient for normal neuronal function (below 23 ml/100 gr/min). Such collaterally perfused areas may include a "chronic ischemic penumbra". Emboli causing MCA occlusions commonly disintegrate and/or migrate more peripherally within the first few weeks post stroke. This leads to reperfusion and changes of ischemic infarcts into hyperemic infarcts where flow is severely increased. The vascular reactivity is completely abolished in hyperemic infarcts and the hyperemic state lasts for about two weeks. Probably, anemic infarcts are equivalent to ischemic infarcts while the hemorrhagic variety is equivalent to hyperemic infarcts. The "partial infarct" with selective neuronal necrosis occurs in experimental animals after MCA occlusions of less than four h but not after permanent MCA occlusion. The significance of partial infarction in human stroke is not clarified. The extent of irreversible tissue damage can be reduced only if therapy sets in within 4-8 h after the occlusion. If a "chronic penumbra" exists the extension of reversible tissue damage can be reduced if therapy aimed at increasing the blood flow in the penumbra sets in within weeks or even months after the stroke.(ABSTRACT TRUNCATED AT 400 WORDS)     

Creaming and plasma clearance rate of intravenous fat emulsion in critically ill patients

Intravenous fat emulsion incubated with serum or plasma in vitro may result in the aggregation of fat (creaming). Twenty critically ill patients were tested for in vitro creaming of the fat emulsion Intralipid. An intravenous fat tolerance test was used to determine the plasma clearance rate of Intralipid in each patient. Eleven patients (55%) were found to be creamers. These patients had a higher mean plasma clearance rate of Intralipid than non-creamers (5.73 +/- 0.56 vs. 2.77 +/- 0.37% per min; p < 0.001); however, the rates of both groups were within the range reported in normal healthy subjects. Mean C-reactive protein concentration was significantly higher (p < 0.01), and albumin levels were lower (p < 0.01) in creamers compared to non-creamers. Ionized calcium levels did not differ between the two groups. The results of this study indicate that in vitro creaming is common in acutely ill patients. The clinical significance of creaming is probably minimal since creamers tolerated 50 to 100 g/day of intravenous fat emulsion while receiving total parenteral nutrition. Creaming was uncommon when the fat was mixed with blood in vitro.     

An Overview of the Treatment Options Used for the Management of COVID-19 in Pakistan: Retrospective Observational Study

BackgroundSince the first reports of COVID-19 infection, the foremost requirement has been to identify a treatment regimen that not only fights the causative agent but also controls the associated complications of the infection. Due to the time-consuming process of drug discovery, physicians have used readily available drugs and therapies for treatment of infections to minimize the death toll.ObjectiveThe aim of this study is to provide a snapshot analysis of the major drugs used in a cohort of 1562 Pakistani patients during the period from May to July 2020, when the first wave of COVID-19 peaked in Pakistan.MethodsA retrospective observational study was performed to provide an overview of the major drugs used in a cohort of 1562 patients with COVID-19 admitted to the four major tertiary-care hospitals in the Rawalpindi-Islamabad region of Pakistan during the peak of the first wave of COVID-19 in the country (May-July 2020).ResultsAntibiotics were the most common choice out of all the therapies employed, and they were used as first line of treatment for COVID-19. Azithromycin was the most prescribed drug for treatment. No monthly trend was observed in the choice of antibiotics, and these drugs appeared to be a random but favored choice throughout the months of the study. It was also noted that even antibiotics used for multidrug resistant infections were prescribed irrespective of the severity or progression of the infection. The results of the analysis are alarming, as this approach may lead to antibiotic resistance and complications in immunocompromised patients with COVID-19. A total of 1562 patients (1064 male, 68.1%, and 498 female, 31.9%) with a mean age of 47.35 years (SD 17.03) were included in the study. The highest frequency of patient hospitalizations occurred in June (846/1562, 54.2%).ConclusionsGuidelines for a targeted treatment regime are needed to control related complications and to limit the misuse of antibiotics in the management of COVID-19.