Tibial tunnel enlargement after anatomic anterior cruciate ligament reconstruction with a bone–patellar tendon–bone graft. Part 1: Morphological change in the tibial tunnel

BackgroundThree-dimensional (3D) computed tomography (CT) is reliable and accurate imaging modality for evaluating tunnel enlargement after anterior cruciate ligament (ACL) reconstruction. The purpose of this study was to evaluate the tibial tunnel enlargement including the morphological change after anatomic ACL reconstruction with a bone–patellar tendon–bone (BTB) graft using 3D CT models.MethodsEighteen patients with unilateral ACL rupture were included. The anatomic rectangular-tunnel (ART) ACL reconstruction with a BTB autograft was performed. 3D CT models of the tibia, the tibial tunnel, and the bone plug at 3 weeks and 1 year after surgery were reconstructed and superimposed using a surface registration technique. The cross-sectional area (CSA) of the tibial tunnel perpendicular to the tunnel axis was evaluated at the aperture and 5, 10, and 15-mm distal from the aperture. The CSA was measured at 3 weeks and 1 year after surgery and compared between the two time points. The locations of the center and the anterior, posterior, medial, and lateral edges of the tunnel footprint were also evaluated based on the coordinate system for the tibial plateau and compared between the two time points.ResultsAt the aperture, the CSA of the tibial tunnel at 1 year after surgery was significantly larger by 21.9% than that at 3 weeks (P < 0.001). In contrast, the CSA at 1 year was significantly smaller than that at 3 weeks at 10 and 15-mm distal from the aperture (P = 0.041 and < 0.001, respectively). The center of the tunnel footprint significantly shifted postero-laterally with significant posterior shift of the anterior/posterior edges and lateral shift of the lateral edge (P < 0.001).ConclusionThe tibial tunnel enlarged at the aperture by 22% 1-year after anatomic ACL reconstruction with a BTB graft, and the tunnel morphology changed in a postero-lateral direction at the aperture and into conical shape inside the tunnel.     

Impact of sonography on surgery for primary hyperparathyroidism

The impact of preoperative sonographic localization of enlarged parathyroid glands was evaluated from the standpoint of operative time and complication rates. There was a reduction in the average time from 135 minutes when findings were false-negative to 111 minutes when findings were positive. The rate of complication was not changed by accurate preoperative localization. When the operative goal is to find all parathyroid glands in every patient, the value of preoperative localization of parathyroid tumors by any current method is slight. Should operative policy favor a search for only one enlarged and one normal gland, or should methods improve to the point that even normal parathyroid glands can be located reliably, noninvasive localization should prove to be useful, safe, and cost-effective, even when it is carried out before initial operation.     

LAPAROSCOPIC SPLENECTOMY

The innovations in laparoscopic technology have expanded the variety of general surgical procedures amenable to laparoscopic approach. An initial experience with eight cases of laparoscopic splenectomy is presented. The indications for splenectomy were immune thrombocytopenic purpura (ITP, n= 6). hereditary spherocytosis (n = 1) and enlarged spleen with filling defects (n = 1). There were six females and two males, aged 27 to 46 years. Seven patients had the spleen removed laparoscopically and one had laparoscopically assisted splenectomy. The operations took from 2 h 15 min to 3 h 30 min (mean 2 h 45 min). The spleens removed varied from 70 to 563 g (mean = 250). Blood loss ranged from insignificant to 1400 ml. Significant bleeding was encountered in three patients with moderate splenomegaly (240, 350, 563 g). Two patients received autologous blood transfusion. The average narcotic required was three doses. The patients were discharged after a mean postoperative stay of 3 days (range 2–4). One patient developed a below knee deep venous thrombosis. Laparoscopic splenectomy is possible and promises to provide the advantages associated with other laparoscopic procedures. Patients with an enlarged spleen can present a technical challenge, and there is a potential for significant blood loss. The current technology and laparoscopic expertise means that this procedure should probably be limited to patients whose spleens are not palpable clinically.     

Apical microleakage of root-end cavities prepared by Er, Cr: YSGG laser

The aim of this study is to assess the apical microleakage of the composite filled root-end cavities prepared by an Erbium, Chromium: Yttrium-Scandium-Gallium-Garnet laser. Fifty-five maxillary incisor teeth were enlarged and filled. Following the apical resection, root-end cavities were prepared using conventional methods: either using a bur (n?=?30) or an ultrasonic retrotip (n?=?15). Root-end cavities of the 15 teeth in the bur group were finished with the laser at 3.5 W. All root-end cavities were filled using two-step self-etching primer and composite resin. After 4 months of storage, apical microleakage was measured by a fluid filtration method. Microleakage of composite filled root-end cavities that were prepared by Er, Cr: YSGG was significantly larger than those made by conventional methods (p?<?0.05). In conclusion, using the Er, Cr: YSGG laser has no advantages over conventional root-end cavity preparation methods when a composite filling material is used to seal root-end cavities.     

Electron microscopy of Crotalaria pulmonary hypertension

The lungs of 11 rats fed on Crotalaria spectabilis seeds for periods ranging from 12 to 61 days were examined by both light and electron microscopy. The findings were compared with those obtained from nine control rats given a normal diet. Eight of the 11 test rats showed morphological evidence of pulmonary arterial hypertension in the form of right ventricular hypertrophy; the exceptions were rats killed after receiving the Crotalaria diet for 12, 22, and 29 days respectively. On light microscopy, all the test rats showed exudative lesions in the lungs consisting of eosinophilic alveolar coagulum, intra-alveolar haemorrhage, interstitial fibrosis, and a proliferation of mast cells. Enlarged and proliferated cells were seen to line the alveolar walls or lie free within the alveolar spaces. Electron microscopy showed these cells to be enlarged granular pneumocytes containing enlarged, electron-dense, lamellar secretory inclusions. Scanty macrophages were also seen in the alveolar spaces, in which excessive numbers of myelin figures and lattices were seen: these structures resembled phospholipid membranes and were probably related to pulmonary surfactant. We think that proliferation of granular pneumocytes is a non-specific reaction of the alveolar walls to injury. The alveolar-capillary wall showed interstitial oedema with the formation of intraluminal endothelial vesicles, probably representing the early ultrastructural phase of pulmonary oedema, and more likely to be an effect of the pulmonary hypertension than its cause.     

An association of multiple endocrine neoplasia 2B, a RET mutation; constipation; and low substance P-nerve fiber density in colonic circular muscle

Background

Multiple endocrine neoplasia (MEN) 2B is a rare hereditary syndrome that results from an activating mutation of the RET proto-oncogene. The RET gene is involved in the development of the enteric nervous system. Patients with MEN 2B have enlarged enteric ganglia and may be affected by gastrointestinal dysmotility. A deficiency of the neurotransmitter substance P (SP) has been identified in both pediatric and adult patients with chronic constipation.

Methods

Three patients, in whom constipation was the presenting symptom and MEN 2B had been provisionally diagnosed, underwent genetic analysis. Seromuscular colonic biopsies were taken for immunofluorescence imaging in all 3 patients. A retrospective review of the patient notes was undertaken.

Results

All 3 patients had constipation refractory to conservative treatment. Genetic analyses in the 3 patients confirmed an identical RET mutation (Met918Thr). Immunofluorescence imaging in all 3 patients identified grossly enlarged myenteric plexus ganglia but surprisingly a low density of SP-labeled nerve fibers in the colonic circular muscle. Nitric oxide synthase and vasoactive intestinal peptide labeling were not reduced.

Conclusion

The results show an association between MEN 2B and its most common RET mutation, colonic dysmotility, and low density of SP in the colonic circular muscle. Larger numbers of patients need to be studied to investigate whether low SP is primarily associated with the constipation or RET mutation and if it is a common feature of MEN 2B.     

Splenectomy, suppressor cell activity, and survival in tumor bearing rats

Young female rats of the Fischer strain were subjected to splenectomy at 10 weeks of age. Three weeks later, these animals and a comparable group of intact animals were inoculated subcutaneously with 3 × 10⁶ cells of the syngeneic Ward colon carcinoma. Tumor growth was recorded by serial measurement. Lymph node cells from control, intact tumor-bearing, and asplenic tumor-bearing animals were tested for reactivity in mixed lymphocyte culture (MLC) and for ability to suppress the allogeneic mixed lymphocyte reaction. At 3 weeks after tumor inoculation, lymphocyte reactivity in MLC was somewhat depressed in asplenic tumor-bearing hosts but severely depressed in intact hosts (P < 0.001); suppressor activity was demonstrable in intact hosts but not in asplenic hosts (P < 0.001). At 5 weeks, lymphocyte reactivity in MLC was severely depressed in both groups; suppressor cell activity was present in both groups and differences were no longer significant. Median survival of intact tumor-bearing animals was 97 days after inoculation (P < 0.0001 by the log-rank test), and 120 days in asplenic animals (P < 0.001). We conclude that both depression of lymphocyte reactivity and onset of suppressor activity are delayed in asplenic tumor-bearing animals. Host survival was significantly prolonged.     

Canine left ventricular volume and mass during thoracotomy by two-dimensional echocardiography: Increased ventricular mass after ischemia and reperfusion

Left ventricular end-diastolic volume (V_c) and mass (M_c) were studied in 10 dogs by two-dimensional echocardiography after thoracotomy and construction of a pericardial well filled with sound-conducting gel. Five selected LV sections were obtained in vivo by two-dimensional ultrasound. After X-ray angiography and thermal dilution cardiac outputs, 9 of the 10 hearts were fixed by glutaraldehyde coronary perfusion while filling pressures were maintained equal to LVEDP and RVEDP in vivo. Silastic casts of the left ventricle were used to measure cavity volume (V_c) by displacement, and LV mass was determined by weighing (V_pm). Study of postmortem casts with a Simpson's rule algorithm revealed that volume calculations with two of six possible pairs of orthogonal sections were congruent with the line of identity vs cast displacement volume. Optimum results in vivo were obtained from averaged data based on these section pairs (from three echo sections) as V_c = 0.94V_c + 0.2 (r = 0.88). LV mass was given by M_c = 0.95M_pm + 6.6 (r = 0.90). Systolic volume, stroke volume, and ejection fraction were less satisfactory, reflecting difficulties with long axis sections during systole in the open chest. To examine the suitability of these methods for physiologic studies, LV mass was measured before and after 30 min of normothermic ischemic arrest and reperfusion in six dogs. LV mass increased from 109 ± 7 (SE) g before ischemia to 153 ± 13 g after ischemia (P < 0.01). Two-dimensional echocardiography thus demonstrates unique potential for experimental cardiovascular physiology.     

A novel SOX9 mutation, 972delC, causes 46,XY sex-reversed campomelic dysplasia with nephrocalcinosis, urolithiasis, and dysgerminoma

An 8-year-old phenotypic female with campomelic dysplasia (CD) and 46,XY sex-reversal presented with renal colic. Medullary nephrocalcinosis, urolithiasis, and renal malrotation were diagnosed by computed tomographic scanning. Pelvic sonogram identified an enlarged left gonad. Genetic testing revealed a novel SOX9 heterozygous deletion of a cytosine at nucleotide 972 (972delC), causing a frameshift at codon 200, introducing a stop codon 18 codons further downstream (P200fsX218). At laparoscopic gonadectomy, a left dysgerminoma was removed. This first reported case of dysgerminoma in a sex-reversed patient with CD who also had urolithiasis stresses the importance of prophylactic gonadectomy and urologic evaluations in this susceptible population.     

Dehydration and factors affecting pulmonary antibacterial defenses

Since impaired intrapulmonary bacterial inactivation of Staphylococcus aureus has been described in rats which were dehydrated for 38 hr, the effect of dehydration on several factors known to influence host responses to bacteria in the lung were studied.After 38 hr of dehydration, arterial pH, pCO₂, and pO₂ were unchanged, but plasma osmolality was increased. Surfactant, measured by the bubble stability ratio, was impaired by dehydration. When macrophages were recovered from the lung by bronchial lavage, their number, viability, oxygen consumption, and enzyme (acid phosphatase, β glucuronidase, leucine aminopeptidase) contents were similar to controls. Since normal oxidative metabolism is needed for phagocytosis and normal enzyme content is needed for lytic activity, the alveolar macrophage appears capable of bactericidal activity. A cofactor, perhaps within the alveolar lining fluid, may be necessary for normal activity of the macrophage and was adversely affected by dehydration. Since in vitro studies have demonstrated the need for normal surfactant fraction for maximal bactericidal activity of the alveolar macrophage, the abnormal surface lining material with dehydration may have contributed to the impaired in vivo host defenses.     

Allograft Mucormycosis Due to Rhizopus microsporus in a Kidney Transplant Recipient

Mucormycosis is an uncommon infectious complication with fatal outcome after kidney transplantation. We describe a rare form of mucormycosis in allograft kidney. The patient was a 54-year-old man who underwent deceased-donor transplantation. The patient experienced delayed graft function and new-onset diabetes within 1 week after transplantation. Four weeks after transplantation, he was readmitted because of allograft dysfunction without fever or pain. Ultrasonography showed enlarged allograft with normal blood flow. He was received broad antibiotics for 6 days, but allograft function was not recovered. Seven days after admission, allograft biopsy was performed, and in microscopic examination, extensive necrotic areas with disseminated fungal invasion were seen, and it was identified as Rhizopus microsporus by culture and DNA analysis. With allograft nephrectomy, he was treated with amphotericin B. Despite intensive antifungal drugs after graft nephrectomy, the patient died of disseminated fungal infection.     

超声对移植肝肝门部淋巴结反应性增生的诊断和随访价值

目的探讨超声对移植肝肝门部淋巴结反应性增生的诊断和随访价值。 方法回顾性分析2006年2月至2016年2月在浙江大学医学院附属第一医院肝移植中心行肝移植术并接受超声常规随访1年以上1 019例受者的超声资料,分析和总结87例符合移植后肝门部淋巴结反应性增生受者的临床资料和超声影像特征。 结果肝移植术后1年,肝门部淋巴结反应性增生发生率为8.54% (87/1 019),超声发现淋巴结肿大时间中位数为移植术后55 d (7～270 d);肝门部淋巴结增大单发57例,多发30例;淋巴结平均长径(24.6±6.2) mm,横径(17.4±2.9) mm;内部回声均匀,彩色血流信号不丰富。伴发门静脉受压2例,轻、中度狭窄;包绕肝门血管生长并伴有肝内胆管轻度扩张3例。肝门部肿大淋巴结平均消失或缩小时间为(82±57) d。 结论对肝门部淋巴结反应性增生超声特征的认识可以减少一部分移植肝穿刺活检。超声可以作为肝移植术后辅助诊断和监测肝门部淋巴结反应性增生的有效影像手段。     

Multiple parathyroid adenomas: report of thirty-three cases

An increasing number of patients with primary hyperparathyroidism are found to have two or three enlarged parathyroid glands. Of 865 patients successfully operated on by one surgeon (J.N.A.), multiple enlarged parathyroid glands (adenomas) were found and resected in 33 cases (3.8%), with resulting normocalcemia lasting from 1 to 22 years (mean 5.8). Twenty-nine patients had two adenomas and four had three adenomas. In 28 patients the multiple adenomas were synchronous. Twenty-five patients underwent removal of all of the enlarged parathyroid glands in one operation; in three patients one adenoma was removed, reoperation for persistent hypercalcemia was performed, and a second adenoma was resected with cure. In five patients one adenoma was removed, normocalcemia ensued for 3 to 18 years, and a second (metachronous) adenoma occurred and was resected successfully. Although 10 of 70 enlarged parathyroid glands removed were labeled hyperplasia, cure in all but one of our patients by selective resection of only enlarged parathyroid glands emphasizes the unreliability of histologic criteria in differentiating between parathyroid adenoma and hyperplasia. Based on this study, we support the existence of multiple adenomas and advocate removal of only macroscopically enlarged parathyroid glands in patients with primary hyperparathyroidism.     

Influence of pouch and stoma size on weight loss after gastric bypass

BackgroundEnlargement of the gastric pouch and/or gastrojejunostomy after Roux-en-Y gastric bypass (RYGB) is postulated to be the antecedent to suboptimal weight loss or weight regain. The present study evaluated the gastric pouch and stoma dimensions in RYGB patients and correlated them with the weight loss outcomes.MethodsPatients who underwent upper endoscopy for investigation of gastrointestinal symptoms or weight regain after RYGB were identified. The stoma was considered enlarged if >2 cm in diameter and the pouch was considered enlarged if >6 cm long or >5 cm wide. Successful weight loss was defined as excess weight loss >50% or a body mass index decrease to ≤30 kg/m².ResultsA total of 380 patients had nondiagnostic upper endoscopy findings at a mean post-RYGB interval of 5.9 ± 4.0 years. Among these were 175 patients (group A; 87% women) who had successful weight loss and 205 patients (group B; 86% women) who were referred for investigation of weight regain. The pouch and stoma size were normal in most of the patients in group A (63.4%) compared with 28.8% of the patients in group B (P <.001). The most common abnormality was an enlarged stoma. The pouch length, pouch volume, and stoma diameter correlated inversely with excess weight loss. Multivariate analysis identified that the stoma diameter was independently associated with weight regain after RYGB.ConclusionThe current definition of a “normal” size pouch/stoma is associated with optimal weight loss after RYGB, although this might need to be reviewed. Patients who regain weight are likely to have abnormal anatomy, in particular, stoma enlargement. The surgical RYGB technique and methods of evaluating the gastric anatomy in RYGB patients need to be standardized, intraoperatively and postoperatively.     

Suppression of cellular immunity by anesthesia and operation

The effect on in vivo cellular immunity of anesthesia and operation was evaluated in 250 cancer patients who received sensitizing doses of dinitrochlorobenzene (DNCB). The primary immune response to DNCB of 218 patients who completed the 2-week sensitization period prior to operation was compared with that of 32 patients who had interruption of the sensitization period by general anesthesia or operation. The extent and histologic types of malignances were similar in the two groups; however, 53% of patients who had interruption of sensitization by anesthesia or operation were anergic to DNCB, while only 9% of patients with an uninterrupted sensitization period were anergic (P < 0.001). Similarly, in patients who responded to DNCB, there was an increased incidence of impaired responses in the group who had interruption of the sensitization period. These findings extend previous demonstrations of an immunosuppressive effect of anesthesia and operation as assayed by in vitro correlates of cellular immunity and in vivo response to recall antigens.The results indicate that correlations between primary immune responses to DNCB of tumor-bearing patients and prognosis after treatment may be invalid if the sensitization period is interrupted by anesthesia or operation. Because of the possible facilitation of the dissemination, implantation, and propagation of tumor cells during a period of suppressed cellular immunity related to anesthesia and operation, these results suggest the need for investigating the desirability and means of maintaining and even augmenting cellular immune competence in cancer patients during anesthesia and operation.     

Alterations in thyrotropin (TSH) binding in iodine-deficient rats

Thyrotropin (TSH) is thought to stimulate thyroid activity and growth by binding to TSH receptors on thyroid plasma membranes. Iodine depletion has been shown to increase the sensitivity of the thyroid to the goitrogenic effects of TSH. The present investigation was performed to determine if chronic iodine depletion altered either the number or the affinity of TSH receptor sites in the thyroid. Six paired experiments were performed comparing the binding of ¹²⁵I-labeled bovine TSH to a particulate fraction of thyroid from male Sprague-Dawley rats that had received regular (C) or low iodine diet (LID) for 3 to 7 months. The number of TSH receptors and the association constants of these receptors were calculated from Scatchard plots and binding was compared with glandular concentrations of DNA, RNA, protein, plasma membrane markers (5′-nucleotidase, Mg²⁺ ATPase, Na⁺, K⁺ ATPase), and per thyroid gland. (1) The weights of all animals were initially similar but after 3 to 7 months the LID group (638 ± 139 g (mean ± 1 SD)) was heavier than the C group (544 ± 45 g (P < .01)). (2) Serum TSH concentrations in the LID group (5231 ± 547 ng/ml) were higher than those in the C group (850 ± 221 ng/ml) (P < .005). (3) Thyroid weight, thyroid weight per animal weight, DNA, RNA, total protein, Mg²⁺ ATPase, Na⁺, K⁺ ATPase, and 5′-nucleotidase were all increased in the LID group (P < .005). Histological examination demonstrated that the thyroid enlargement was primarily due to an increase in number of follicle cells, or hyperplasia. (4) The concentration of TSH receptors (maximum binding capacity) per DNA content was similar in the C and LID groups. (5) The concentration of TSH receptors per plasma membrane marker decreased in the LID group (P < .01) primarily because of the large increase in amount of plasma membrane. (6) The total number of TSH receptors per thyroid gland or TSH receptor content increased from 0.52 ± 0.16 × 10¹⁴ in the C group to 2.27 ± 0.79 × 10¹⁴ in the iodine-deficient animals (P < .001), and the association constant in these animals (1.28 ± .27 × 10⁸M^?1) was also higher than that in the C group (0.68 ± 0.16 × 10⁸M^?1) (P < .001). Thus, chronically iodine-deficient rats developed increased serum TSH concentrations and enlarged hyperplastic thyroid glands. Although the number of TSH receptors per DNA or cell did not change in the respective groups, the TSH receptor content and the association constant of these receptors for TSH in the thyroid gland of the iodine-deficient animals increased. It therefore appears that increased serum TSH concentrations in iodine-deficient rats exerts a positive regulatory effect on its own receptors and that alterations in serum TSH level modulate the TSH receptor. Whether this effect is due to a direct effect of TSH on the TSH receptor or an indirect effect secondary to thyroid growth is unknown.     

Accuracy of Computed Tomography–Guided Joint Aspiration and Computed Tomography Findings for Prediction of Infected Hip Prosthesis

BackgroundInfection after total hip arthroplasty remains a diagnostic challenge. We assessed the accuracy of computed tomography (CT)-guided joint aspiration combined with CT findings for prediction of septic hip prosthesis before revision surgery.MethodsA total of 96 patients (64.6% men; mean age, 68 years) scheduled for elective revision surgery due to suspicion of infection after total hip arthroplasty underwent CT-guided joint aspiration. Volume and microbiological cultures of aspirated fluid and salient findings on CT scans, including periprosthetic soft-tissue mass, malpositioning of the prosthesis, periprosthetic osteolysis, reactive enlarged lymph nodes, and heterotopic ossification, were assessed by a blinded radiologist.ResultsSeptic hip prosthesis was shown on revision surgery in 35 patients (36.4%), with Staphylococcus epidermidis isolated in 54.3% of cases. Culture of the aspirated fluid yielded the same microorganism in 24 patients (68.6%). The accuracy of preoperative CT-guided joint aspiration was 86.5%. High volume (>1 mL) of aspirated fluid was recorded in 32 patients (33.3%). In the multivariate analysis, high volume on CT aspiration, accumulation of soft tissue exceeding the joint margin, osteolysis without bone insufflation, and enlarged iliac lymph nodes were significant predictors of infected hip prosthesis. Similar results were obtained after adjustment of the model by the presence of aggressive granulomatosis.ConclusionPreoperative CT-guided joint aspiration is accurate to diagnose septic hip prosthesis based on CT imaging findings and volume and bacterial culture of the aspirated fluid. Enlarged iliac lymph nodes emerged as a strong predictor of infection.     

Surgical treatment for enlarged prostatic utricle and vagina masculina in patients with hypospadias

Fourteen patients with hypospadias were treated surgically for either an enlarged prostatic utricle (6) or vagina masculina (8). Six vaginae masculinae were removed by an extravesical abdominal approach. One enlarged prostatic utricle was removed by the perineal approach. Three enlarged utricles were removed by an abdominoperineal approach. The transtrigonal approach was recently used for three enlarged utricles and one vagina masculina in four patients. Surgical results in these 14 patients were satisfactory. One post-operative complication of transient mild bilateral vesicoureteric reflux was seen after a transtrigonal removal of an enlarged utricle. Potency was not affected in any approaches in four patients who were older than 12 years. The transtrigonal approach was found to be the best for good exposure of the lesion.     

Reimmunization and splenic autotransplantation: A long-term study of immunologic response and survival following pneumococcal challenge

Splenic autografts have phagocytic function and increase survival after experimental sepsis. The long-term effect of transplant viability, phagocytic capacity, and immunologic responsiveness were evaluated. Rats were divided into experimental groups: control, splenectomized, and splenic autotransplant rats. Approximately one-half of the rats were immunized against pneumococcus. Twelve months later, the rats were reimmunized, and the pneumococcal antibody titers were measured. The effect of operation and immunization was determined by challenging rats with intravenously administered pneumococci. Bacterial clearance from the bloodstream was measured and mortality recorded. Spleens were weighed and examined histologically. In unimmunized rats, pneumococcus was cleared from the bloodstream of control rats, whereas splenectomized and splenic autotransplant rats demonstrated a progressive increase of pneumococci in the bloodstream. However, splenic autotransplant rats grew fewer bacteria after challenge (P < 0.05). All control rats survived. Thirty-three percent of splenic autotransplant rats were alive, but significantly fewer splenectomized rats (6%) survived (P < 0.05). After reimmunization, highest antibody titers were noted in control rats (P < 0.05). Splenic autotransplant rats had higher antibody titers than did splenectomized rats (P < 0.05). Reimmunized splenic autotransplant rats had greater survivorship (71%) when compared with reimmunized splenectomized rats (26%) (P < 0.003). At 1 year, transplants were smaller than control spleens (P < 0.001), although histologic integrity was maintained. Splenic autotransplantation results in better phagocytic function, improved response to reimmunization, and increased survival after pneumococcal challenge and may be an important measure in preventing postsplenectomy sepsis.     

The relationship of transmural myocardial blood flow to midwall function

The relationship of transmural myocardial blood flow to midwall function was evaluated in seven adult mongrel dogs anesthetized with morphine SO₄ (3 mg/kg) and a-chloralose (80 mg/kg) and instrumented with catheters for measuring aortic and left ventricular end-diastolic pressures and dp/dt. Three pairs of miniature ultrasonic transducers (3 mm diameter) were positioned at midwall level of the left ventricle along the minor axis within each of the three regions: anterior, lateral, and posterior segments. Transmural blood flow in the epicardium and endocardium was measured utilizing 8- to 10-μm tracer microspheres before and after a 60-sec circumflex occlusion. Functional data for extent (ΔL) and rate (dl/dt) of systolic shortening were determined and systolic excursion was normalized to an initial end-diastolic length of 10 mm. Total circumflex occlusion for 1 min was associated with a severe flow imbalance to the posterior endocardium (endocardium/epicardium 0.2 ± 0.1) resulting in marked functional impairment (ΔL = -0.5 ± 0.2 mm, dl/dt = -1.6 ± 1.1 mm/sec) and holosystolic bulging. Flow within the lateral region was not as severely impaired (endocardium/epicardium 0.5 ± 0.1, P < 0.05), and was associated with less dysfunction (P < 0.01) without regional bulging. Function and flow in the anterior region were augmented. These data suggest that midwall regional function is dependent on flow, especially endocardium. Holosystolic bulging represents marked flow reduction (97%) while flow may be decreased by 79% without holosystolic bulging.