Video-assisted orotracheal intubation in mice

Orotracheal intubation in mice is a complicated technique because of the peculiar oropharyngeal anatomy and the difficulty in visualizing the laryngis aditus. Here we report a new and simple method for rapid endotracheal intubation by using a small bore, straight fibre-optic arthroscope. Under endoscope-assisted visualization of the laryngis aditus, a polyethylene cannula, inserted on a guide-wire in order to facilitate the introduction of the tip across the vocal cords, was advanced in the trachea. The success rate of intubation was 100%. We were also able to re-intubate the mice 4 and 8 weeks later without any major complications. We conclude that this method can be easily and safely used for studies where controlled pulmonary ventilation is necessary.     

Postoperative management after thymectomy.

This paper reports a retrospective study of the preoperative and postoperative management of 28 patients who underwent thymectomy between 1956 and 1973. Patients who received postoperative artificial ventilation were compared with the group who did not with respect to sex, age, severity of disease, preoperative vital capacity, and thymic histology. Evidence is presented that postoperative artificial ventilation is required when the preoperative vital capacity with the patient on optimum anticholinesterase treatment is less than 2 litres. Additional features associated with a probable need for artificial ventilation were the presence of a thymoma, bulbar symptoms, especially dysphagia, and age over 50 years. These should be taken into account in any patient whose vital capacity is close to the critical level of 2 litres. When postoperative ventilation was required it was usually necessary for 12 days or more, and tracheostomy should therefore be done at or before thymectomy. Most patients in this series received the same dose of anticholinesterases after operation as before it and no evidence was found of a sudden decrease in requirements for anticholinesterase therapy. Two patients did not, and in them a myasthenic crisis was precipitated. We propose that the preoperative drug regimen can be continued in the immediate postthymectomy period, allowing selection of patients for tracheostomy and artificial ventilation primarily on the basis of the preoperative vital capacity.     

A technique for transcervical intrauterine insemination of ewes

In commercial artificial insemination (AI) of sheep, fresh extended semen is deposited into the vagina or cervical os, or fresh extended or frozen semen is placed laparoscopically into the uterus. Transcervical intrauterine insemination of the ewe is not used commercially. In this study, methods of restraint and instrumentation for AI were evaluated and modified to produce a transcervical intrauterine technique suitable for commercial application. Four methods of restraint, four vaginal specula, three forceps and four instruments suitable for transcervical passage were compared. From these comparisons a technique was developed in which the ewes were positioned in dorsal recumbency with their hindquarters elevated. The vagina was dilated using a duck-billed speculum, the cervix was grasped and retracted using forceps, and an inseminating instrument was introduced into the cervical opening and manipulated through the cervical canal. The technique was repeated on 89 mature, multiparous ewes: the difficulty in locating the cervical opening, the force required to retract the cervix and the time required to penetrate into the uterus were recorded. Uterine penetration was achieved in 82% of the ewes. This technique has the potential to be applied in commercial artificial insemination programs of sheep.     

A method of thymectomy in macaques

The aim of this study was to develop an operation for total thymectomy suitable for nonhuman primates. The thymus was removed from 24 macaque monkeys from fetal to adult life by a cervicothoracotomy and blunt gauze dissection. Mean wet weight of the thymus rose from 150 mg (range 50-250 mg) in fetal animals to 2.5 gm (range 0.3-4.2 gm) in prepubertal monkeys. Nonhuman primate thymic weight fell steadily and uniformly with age by over 300% when plotted as a function of body weight. This surgical technique appears to be a valid method of total thymectomy in macaque monkeys.     

Technique for transcervical intrauterine inoculation of the mouse.

Suspensions of india ink or gonococci were inoculated into the murine uterus through the cervix with a simple plastic vaginal speculum and a 23 gauge blunted needle. The inoculated suspensions were distributed throughout both uterine horns, cervix, and vagina, but did not flow into the peritoneal cavity. This method avoided surgical stress as well as being simple, fast, and reproducible.     

A method for transcervical embryo collection in the pig

Five cyclic primiparous sows were used to test a surgical procedure for in vivo transcervical collection of pig embryos. The procedure consisted of shortening the uterine horns. After surgery, all sows returned to estrus and embryos were recovered following artificial insemination. Transcervical uterine flushing was carried out in four sows. On average 3.6 +/- 1.5 (mean +/- SD) embryos were recovered from the five sows. The results indicate that it is possible to recover embryos transcervically from sows with a resectioned uterus.     

The effect of thymectomy on lupus-prone mice

The effect of neonatal thymectomy on the induction and/or modification of murine SLE disease was examined in several representative groups of mice with early-life SLE (MRL/Mp-lpr/lpr females, BXSB males, (NZB X W)F1 females, (NZW X BXSB)F1 males and females), late-life SLE (MRL/Mp-+/+ and BXSB females), and normal strains (BALB/c and C57BL/6 females). Our results indicated that thymectomy prevented disease only in the MRL/Mp-lpr/lpr SLE mice, and that this effect diminished as thymectomy was delayed beyond 3 wk post-natally. In the other SLE mice studied, neonatal thymectomy did not modify disease symptoms to any significant degree. Moreover, depletion of mature T cells from donor BXSB male bone marrow did not affect the expression of early-life SLE in thymectomized BXSB female recipients. Neonatal thymectomy did not induce SLE in normal mice. Of note, neonatal thymectomy did not completely deplete the Thy-1.2+ cell population, i.e., 10 to 15% remained in the spleens of the thymectomized mice. This incomplete T cell depletion, together with the previously demonstrated dependence on and hyperresponsiveness of BXSB and (NZB X W)F1 B cells to T helper cell-derived accessory signals, cast doubts on earlier conclusions that B cells from some SLE mice can autonomously proliferate and differentiate to autoantibody-secreting cells. It seems more appropriate to conclude that B cells from the various SLE mice vary in their degree of response to, and production of, T cell-derived helper signals, and thus in their expression of B cell hyperactivity and disease.     

Kinetics of T cell turnover following thymectomy

We develop a mathematical formula that provides the number of cells in an isolated population that have divided k times in n days (O< or =k< or =n). This differential cell division formula is applied to the kinetics of peripheral T cells in the diabetes-prone BB rat following thymectomy. These rats received daily intraperitoneal injections of the DNA precursor, bromodeoxyuridine (BrdUrd), over a period of 12-13 days. As the cells divided, they incorporated BrdUrd progressively into their DNA molecules, and the differential formula provides a close prediction of the fraction of BrdUrd-positive T cells present each day during this 'pulse' phase. No further BrdUrd was administered after 13 days, and the diminishing fraction of BrdUrd-positive cells was recorded for several more weeks. The differential cell division formula was capable of describing the rather complex form of the retention curve as BrdUrd-tagged DNA molecules passed to progeny cells during this 'chase' phase. We believe that this simple formula may be found generally useful in describing cell kinetic data in mitotically active cells.     

An instrument for transcervical recovery of embryos from heifers

A non-surgical system of embryo recovery is described. It consists of a rigid probe of small diameter (4 mm) for recovering the embryos from young heifers (10 to 12 days after estrus). An average of 6.35 eggs were recovered per donor from 64 heifers 15 to 22 month-old having more than two palpable corpora lutea after superovulation. Forty donors were slaughtered after recovery to determine the number of ovulations, the state of the uterus and to do a post-mortem perfusion. The average recovery rate of embryos was 56.4 % ; an additional 9 % were recovered after slaughter. We compared two recovery methods differing in mode of liquid return ; no significant differences were found. Twenty-four animals not slaughtered after recovery returned to heat a mean 23.8 days after induced estrus (control cycle).     

电视胸腔镜在闭合性胸外伤诊治中的应用

目的:探讨电视胸腔镜手术(video-assisted thoracoscopic surgery,VATS)在闭合性胸外伤中诊断、治疗中的价值。方法:2004年6月～2011年6月选择68例闭合性胸外伤患者,应用VATS进行探查、诊断,同时进行肺修补、肺楔形切除、肋间血管止血、肋骨骨折固定等操作以及小切口辅助手术。结果:68例经VATS探查损伤情况:肺裂伤30例,凝固性血胸15例,肋间血管损伤10例,肋骨骨折需手术复位、固定12例,肺内血肿形成5例,膈疝3例,胸廓内血管损伤2例。VATS行肺修补术25例,肺楔形切除术7例,血管止血术12例,肋骨骨折复位、固定术12例,VATS辅助胸壁小切口肺叶切除术3例,膈疝修补术3例。VATS手术时间25～125 min,平均71.7 min。术后1～7 d胸腔少量积液、积气9例,少量咯血8例。68例随访2～17个月,平均9.2个月,复查胸片显示患肺复张良好,胸腔无积液、积气。结论:闭合性胸外伤患者应用VTAS诊治,可使诊断及时、准确,患者创伤小、恢复快,疗效满意。     

Non-invasive early prenatal molecular diagnosis using retrieved transcervical trophoblast cells

Fetal DNA was recovered from 17 of 39 (44%) transcervical cell (TCC) samples obtained between 7 and 9 weeks of gestation by endocervical canal flushing. Trophoblast retrieval was adequate for polymerase chain reaction (PCR) amplification of Y chromosome-specific DNA sequences and detection of paternal-specific microsatellite alleles. The fetal sex predicted by PCR in TCCs was confirmed in all cases by karyotype analysis of chorionic villi at 10 weeks of gestation. The absence of the disease-associated paternal alleles in TCC samples from two pregnancies at risk for spinal muscular atrophy and myotonic dystrophy predicted unaffected fetuses in agreement with subsequent results on chorionic villi and newborns' leukocytes. A trisomy 21 fetus was diagnosed in TCCs using fluorescent in situ hybridization (FISH) and semiquantitative PCR analysis of superoxide dismutase-I (SOD 1). Present experience indicates that TCC sampling is a promising technique for early prenatal monitoring of Mendelian disorders and chromosome aneuploidy.