Häufigkeit pathologischer Veränderungen des oberen Gastrointestinaltraktes bei Patienten vor Herzoperationen

Resümee Schwerwiegende gastroduodenale Erkrankungen sind bei fast der Hälfte aller Patienten, die sich einer Operation am offenen Herzen unterziehen müssen, auch bei Fehlen von Symptomen nachweisbar. Das erhebliche Überwiegen von Magenläsionen spricht dafür, daß die arteriosklerotisch bedingte Perfusionsminderung der Schleimhaut die entscheidende Ursache hierfür ist. Routinemäßige präoperative Ösophago-Gastro-Duodenoskopien können die nicht unerhebliche durch gastrointestinale Komplikationen bedingte postoperative Mortalität senken helfen.

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Pathological changes in the upper gastrointestinal tract in patients awaiting open heart surgery

Summary While waiting for open heart surgery, in 153 patients (104 male, 49 female, 22–76 years of age) without gastrointestinal symptoms and/or history esophago-gastro-duodenoscopy was performed. 124 patients suffered from coronary heart disease, 29 from valvular defect, aneurysm of the sinus of Valsalva or tumor of the heart.In 47.1% endoscopy revealed serious abnormal findings: in 16.3% gastric ulcer, in 20.9% erosive gastritis, duodenal ulcer and erosive duodenitis in 5.2%, respectively, 1 case of gastric carcinoma, 2 of large polyps and 3 of reflux esophagitis of higher degree (totally 3.9%).In patients with coronary artery disease, the relation of erosive and ulcerous gastric lesions as compared with those of duodenal origin was 41, in patients with other cardiac diseases it was 21, respectively (p<0,001).Compared with a normal population, the incidence of pathological gastric findings was 54-fold higher in our patients, and 1.7-fold concerning duodenal lesions, respectively (p<0.001).51 patients on acethylsalicylic acid (160 mg/ die) showed pathologic findings in 41.2%, and 96 patients without ulcer-inducing therapy in 51%. Thus, low-dose Aspirin does not seem to have serious gastric side effects.The results of the study stress the necessity of routinely performed endoscopy of the upper gastrointestinal tract in patients awaiting open heart surgery. This will lead to a lower incidence of serious gastrointestinal complications postoperatively, which are known to have a high mortality.

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Abkürzungen ASS Azetylsalizylsäure - J. Jahre - GI-Trakt Gastrointestinaltrakt     

小鼠角膜的发生与细胞凋亡

目的 通过观察小鼠角膜的发生过程,探讨角膜细胞的增殖与凋亡对角膜结构修复与塑形的作用。方法 各日龄共计120只小鼠,用HE染色或4’,6-二脒基-2-苯基吲哚（DAPI）染色对小鼠角膜的一般结构进行观察;用5′-溴脱氧尿嘧啶核苷（BrdU）技术标记角膜增殖细胞和免疫荧光法标记干细胞和凋亡细胞。结果 胚胎发育及出生后早期,角膜以实质层的发育为主。出生14d（P14）左右,角膜上皮细胞层开始增殖分化为两层细胞,同时内皮细胞也开始分化。至P30时,我们可以辨别出角膜的6层结构。BrdU阳性细胞主要存在实质层中的成纤维细胞,出生以后也可见于角膜上皮细胞层和内皮细胞层。随着角膜发育,P10左右,其他层的BrdU阳性细胞都消失,仅存在于角膜上皮细胞层。增殖细胞核抗原（PCNA）阳性细胞在发育早期散在分布于角膜的各层,P14以后PCNA阳性细胞均匀的分布于角膜上皮细胞的基底层,并维持在稳定状态。在角膜发育早期,在各层可见许多细胞凋亡。结论 角膜的发育与其感光功能形成的过程相一致,角膜干细胞的增殖与其修复有关;有大量的凋亡细胞参与角膜结构的塑形。     

Sagittal laxity in vivo after total knee arthroplasty

Introduction A stress arthrometry study of 77 knees undergoing total knee arthroplasty was performed to determine the difference in anteroposterior (AP) laxity between posterior cruciate ligament (PCL)-retaining (PCLR) and PCL-substituting (PCLS) prostheses using the Genesis I TKA.Materials and methods Fifty-three knees had PCLR and 24 had PCLS prostheses. The selected patients had successful arthroplasties after a minimum follow-up of 5 years. AP laxity was measured with a KT-2000 arthrometer (Medmetric, San Diego, CA, USA) using standard protocols.Results At 30° of flexion, there was no statistical difference in anterior (PCLR: 4.7 mm, PCLS: 4.5 mm), posterior (PCLR: 1.1 mm, PCLS: 0.7 mm), or total (PCLR: 5.8 mm, PCLS: 5.3 mm) displacement. At 75°, significant differences were seen in both anterior (PCLR: 3.3 mm, PCLS: 2.3 mm) and total (PCLR: 4.8 mm, PCLS: 3.4 mm) displacement (p=0.001 and p=0.009, respectively), although there was no statistical difference in posterior displacement (PCLR: 1.5 mm, PCLS: 1.1 mm).Conclusion The above values are considered the suitable degree of AP laxity in total knee arthroplasty for a satisfactory clinical outcome 5–9 years after surgery. The PCL in a PCLR prosthesis and the central tibial spine and femoral cam in a PCLS prosthesis might play comparable roles in determining the laxity in the posterior direction in these prostheses.     

Spontaneous late dislocation of the high flexion tibial insert after Genesis II total knee arthroplasty. A case report

We present the first case of late spontaneous dislocation of a high flexion polyethylene insert after Genesis II total knee arthroplasty. Dislocation of the fixed insert occurred at 14 months post surgery while walking down a steep aircraft staircase. The total knee arthroplasty had been uneventful till that moment. The clinical presentation, possible causes and management are discussed. A surgical error, failure to remove a posterior femoral osteophyte, seems the most probable cause for the late insert dislocation in our case.     

De novo and salvage pathways of DNA synthesis in primary cultured neurall stem cells

We studied the de novo and salvage pathways of DNA synthesis in sphere-forming neural stem cells obtained from mouse embryos by a neurosphere method. The former pathway needs folic acid (FA) for nucleotide biosynthesis, while the latter requires deoxyribonucleosides (dNS). We examined the proliferative activity of sphere-forming cells in E14.5 embryos by counting the number of spheres formed in media that lacked FA and/or dNS. Proliferation failure and apoptosis occurred in a deficient medium lacking of both FA and dNS. Spheres formed in the deficient medium supplemented with dNS, without FA, did not produce neuron, but rather only seem to generate astrocytes and oligodendrocytes when plated under differentiation condition in culture. On the other hand, a subpopulation of cultured cells formed spheres in the deficient medium supplemented with FA alone in an appropriate concentration, and did possess the self-renewing and multipotential characteristics of neural stem cells. Spheres formed in the media containing low dose Azathioprine and methotrexate, inhibitors of de novo DNA synthesis, were selectively prevented from producing neurons even in the presence of FA. These results suggested that activating de novo DNA synthesis was needed for neural stem cells to proliferate with multipotentiality.     

下丘脑-脑垂体-甲状腺发生发育关系的研究

以无脑儿为实验材料，并以正常胎儿作对照，观察了25例无脑儿的下丘脑、脑垂体与甲状腺发育的关系。结果表明，无脑儿有发育正常的脑垂体者，无论是否有下丘脑，甲状腺的发育近似正常。无脑垂体者或脑垂体发育不良。甲状腺则缺如或萎缩、发育不良。结果提示，脑垂体不仅对甲状腺的分泌活动进行调节，而且脑垂体与甲状腺的发育关系密切，而下丘脑-脑垂体-甲状腺可能在一定时间后才发生功能关系。     

Evaluating the “Patella-Friendly” Concept in Total Knee Arthroplasty: A Minimum 15-Year Follow-Up Outcome Study Comparing Constant Radius,Multiradius Cruciate-Retaining,and Nonanatomical Cruciate-Retaining Implants

BackgroundPatella-friendly femoral components were developed in order to reduce anterior knee pain and patellofemoral complications in total knee arthroplasty (TKA), but their effect on long-term outcome is still unclear.MethodsWe retrospectively evaluated prospectively collected data from 3 groups consisting of 100 patients (100 knees in each). In group A, the constant radius a-MP, in group B the multiradius cruciate-retaining Genesis II, and in group C the nonanatomic, multiradius, cruciate-retaining AGC TKA was implanted. Patients of all groups were matched for age, gender, side, body mass index, and length of follow-up. Preoperative and postoperative clinical outcome data in the form of Knee Society System (KSS), Short Form-12, Western Ontario and McMaster University Osteoarthritis Index, and Oxford Knee Score were available at regular intervals for groups A and B. For patients of group C, KSS score data were available at the same time intervals. In all groups, the patellofemoral compartment was assessed using the Clinical Patella Score scale. Anterior knee pain, secondary patella resurfacing, implant failure, and radiological outcome were assessed in patients of all groups.ResultsAt 10-year and 15-year follow-up, patients of group A showed statistically significant (s.s.) higher (all P = .000) KSS values as compared to those of groups B and C. At 15-year follow-up, patients of group B showed s.s. higher (P = .001) KSS values as compared to those of group C. At 10-year and 15-year follow up, patients of group A showed s.s. higher (all P = .00) Western Ontario and McMaster University Osteoarthritis Index and Oxford Knee Score values as compared to those of group B. At 15-year follow-up only, patients of group A showed s.s. higher (P = .00) Short Form-12 (physical) values as compared to those of group B. In terms of Clinical Patella Score, patients in group A had s.s. higher values (P = .05) when compared to those of groups B and C. Anterior knee pain was recorded in 4.4% of TKAs in group A, 7.5% in group B, and 17.2% in group C. One (1.1%) patient in group A, 3 (3.25%) in group B, and 7 (8%) in group C underwent secondary resurfacing.ConclusionAnatomical, patella-friendly, constant radius femoral components outperform others in reducing anterior knee pain and patella complications in TKA in which the patellae are left nonresurfaced.     

Recurrent dissociation of the tibial insert after mini-subvastus posterior-stabilized total knee arthroplasty: A case report

We report here on an unusual case of recurrent dissociation of a polyethylene tibial insert from its metal baseplate after high-flex posterior-stabilized (PS) Genesis II total knee arthroplasty with using the mini-subvastus approach. After the 1st episode of dissociation, which had happened 1 month after the primary surgery, we changed the tibial insert and found damages on the dovetails and the post of the retrieved insert. Unfortunately, the patient suffered the same dissociation 1 month after the tibial insert was changed. This case illustrates that incomplete seating of the insert due to limited surgical exposure and anterior impingement of the high-flex PS post may contribute to the risk of dissociation.     

Estimating the date of origin of an HIV-1 circulating recombinant form

HIV is capable of frequent genetic exchange through recombination. Despite the pandemic spread of HIV-1 recombinants, their times of origin are not well understood. We investigate the epidemic history of a HIV-1 circulating recombinant form (CRF) by estimating the time of the recombination event that lead to the emergence of CRF33_01B, a recently described recombinant descended from CRF01_AE and subtype B. The gag, pol and env genes were analyzed using a combined coalescent and relaxed molecular clock model, implemented in a Bayesian Markov chain Monte Carlo framework. Using linked genealogical trees we calculated the time interval between the common ancestor of CRF33_01B and the ancestors it shares with closely related parental lineages. The recombination event that generated CRF33_01B (t_rec) occurred sometime between 1991 and 1993, suggesting that recombination is common in the early evolutionary history of HIV-1. The proof-of-concept approach provides a new tool for the investigation of HIV molecular epidemiology and evolution.