The representation of the body surface in S-I of cats

In both cats and monkeys, the traditional region of the first somatosensory area of cortex, S-I, has been described as containing four strip-like architectonic fields, areas 3a, 3b, 1, and 2. In monkeys, a number of recent studies have provided evidence that each of these architectonic fields constitutes a separate representation of the body. Because of the observations in monkeys, we decided to re-examine the S-I region of cats to determine whether the evidence supported the traditional concept of a single representation, or the existence of several representations related to the described architectonic fields. Microelectrode multiunit mapping techniques were used to determine the somatotopic organization of the S-I region of 10 cats. The results indicate that a single representation of the body surface occupies most or all of the traditional S-I region including cortex defined as area "3b," area "1," and much of area "2," but excluding area "3a." Neurons throughout this single representation were activated by cutaneous stimuli, indicating that all parts of S-I receive input from cutaneous receptors. Neurons in area 3a were activated by inputs from deep receptors, as reported by others. Neurons caudal to S-I were activated by cutaneous stimuli and appeared to constitute the additional body surface representations of S-II and possibly S-III. Thus, the significance of the architectonic fields "3b," "1," and "2" is quite different in cats than in monkeys. We propose that most or all of these three fields, as described in cats, constitute the homologue of area 3b in monkeys.     

Acute neurotoxicity of the Lathyrus sativus neurotoxin, L-3-oxalylamino-2-aminopropionic acid, in the squirrel monkey.

This paper provides the first evidence that the Lathyrus sativus neurotoxin, l-3-oxalylamino-2-aminopropionic Acid (OAP), is toxic when administered intraperitoneally to a primate with a mature bloodbrain barrier. Drowsiness, vomiting, muscle tremors, twitching, convulsions, and death occurred in young male squirrel monkeys (Saimiri sciureus) following injection of 4.26 and 11.4 μmol (0.750 and 2.00 mg) OAP/g body wt. Electroencephalographic changes characteristic of each stage of intoxication were observed. Unchanged OAP was recovered from brain of intoxicated animals. These observations support a possible role for OAP in the etiology of human neurolathyrism, a paralytic disease prevalent among adults in Central India who have consumed large quantities of L. sativus seeds for several months.     

Tensile strength of spinal ligaments

Spinal ligaments from 41 fresh human male cadavers were tested. The ligaments were tested in situ by sectioning all elements except the one under study. The force deflection curves demonstrated a sigmoidal shape, and the point at which an increase in deflection was obtained with decreasing force was taken as failure. The force and deformation at failure are shown for each ligament as a function of spinal level.     

Radiation dose reduction during hysterosalpingography: an application of scanning-beam digital radiography

Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence.     

Sera from patients with heparin-induced thrombocytopenia generate platelet-derived microparticles with procoagulant activity: an explanation for the thrombotic complications of heparin-induced thrombocytopenia

Heparin-induced thrombocytopenia is characterized by moderate thrombocytopenia and thrombotic complications, whereas quinine/quinidine-induced thrombocytopenia usually presents with severe thrombocytopenia and bleeding. Using flow cytometry and assays of procoagulant activity, we investigated whether sera from patients with these immune drug reactions could stimulate normal platelets to generate platelet-derived microparticles with procoagulant activity. Sera or purified IgG from patients with heparin-induced thrombocytopenia stimulated the formation of platelet-derived microparticles in a heparin-dependent fashion. Further studies showed that heparin-induced thrombocytopenia sera also produced a marked increase in procoagulant activity. In contrast, sera from patients with quinine- or quinidine-induced thrombocytopenia did not generate platelet-derived microparticles nor generate increased procoagulant activity. However, quinine/quinidine-induced thrombocytopenia sera produced a significant increase in the binding of IgG to platelets in a drug-dependent fashion, whereas sera from patients with heparin-induced thrombocytopenia demonstrated no drug-dependent binding of IgG to platelets. We also observed increased levels of circulating microparticles in patients with acute heparin-induced thrombocytopenia compared with control patients. Our observations indicate that the generation of procoagulant platelet-derived microparticles in vivo is a plausible explanation for the thrombotic complications observed in some patients with heparin-induced thrombocytopenia.     

去甲硫氨酸全肠外营养对大鼠血清氨基酸谱的影响

目的观察去甲硫氨酸全肠外营养对大鼠血清氨基酸谱等的影响.方法 Wistar大鼠24只,随机分为含甲硫氨酸(+MetTPN,n=12)和去甲硫氨酸全肠外营养2组(-MetTPN,n=12),分别给予相应的TPN支持.治疗7d后,每组随机抽取6只大鼠处死,检测血清FAA(HPLC法)、肝肾功能和全血常规,同时作心、肺、肝、肾组织病理学检查.两组其余大鼠继续原TPN治疗,观察生存期.结果 -MetTPN组大鼠血清游离Met、Cys明显降低,Asp、Glu、Ser等显著增高;大鼠体重下降;血清总蛋白和白蛋白水平下降;血常规和肾功能未见明显异常;组织学检查见肝细胞轻度肿胀,细胞核仁增粗,心肺肾未见明显异常;平均生存18d.对照组上述检查未见异常,除一只大鼠因导管并发症于TPN第16d死亡,其余大鼠全部存活.结论 -MetTPN一周可致大鼠血清游离Met、Cys明显降低和Asp、Glu、Ser等显著增高,及轻度肝功能改变;随着-MetTPN时间延长,出现严重的代谢紊乱和器官功能障碍导致死亡.     

Assessing Antibody Strength: Comparison of MFI,C1q,and Titer Information

The presence of donor‐specific HLA antibodies before or after transplantation may have different implications based on the antibody strength. Yet, current approaches do not provide information regarding the true antibody strength as defined by antigen–antibody dissociation rate. To assess currently available methods, we compared between neat mean fluorescence intensity (MFI) values, C1q MFI values, ethylenediaminetetraacetic acid (EDTA)‐treated samples, as well as titration studies and peak MFI values of over 7000 Luminex‐based single‐antigen HLA antibody data points. Our results indicate that neat MFI values do not always accurately depict antibody strength. We further showed that EDTA treatment (6%) does not always remove all inhibitory factors compared with C1q or titration studies. In this study of patients presenting with multiple antibody specificities, a prozone effect was observed in 71% of the cohort (usually not affecting all antibody specificities within a single serum sample, though). Similar to titration studies, the C1q assay was able to address the issue of potential inhibition; however, its limitation is its low sensitivity and inability to detect the presence of weak antibodies. Titration studies are the only method among the approaches used in this study to provide information suggesting antigen–antibody dissociation rates and are, therefore, likely to provide better indication of true antibody strength.     

Axial Tension Model of Spinal Cord Injury

ABSTRACT

The purpose of this investigation was to determine the safety and efficacy of subtrigonal, periureteral injections of autogenous fat grafts for the treatment of vesicoureteral reflux.

Seven patients (12 renal units) with vesicoureteral reflux were treated with subtrigonal autogenous fat injection. Fat harvesting was obtained from abdominal and thigh subcutaneous tissue. Approximately 2 ml of fat was injected beneath each ureteral orifice with a modified 10 Fr needle through a 23.5 Fr rigid cystoscope. Two of the seven patients experienced durable (six months) resolution of reflux. In three patients, reflux resolved but recurred within three months and another developed recurrent reflux within six months. In one patient with a periureteral diverticulum, proper positioning of the needle tip for effective fat injection was not possible, resulting in persistent reflux. Two of the five patients with persistent reflux demonstrated a diminished grade of reflux on follow-up cystography. Neither complications nor ureteral obstruction have been encountered.

The subtrigonal injection technique can be used with autogenous adipose tissue to treat vesicoureteral reflux. Anatomic variation may determine those patients less likely to enjoy durable results. Clinical success and reabsorption of the fat cannot be predicted or controlled at the present time. The ideal periureteral bulking agent for the treatment of vesicoureteral reflux remains to be determined.