Selective parathyroid auto‐transplantation during thyroidectomy

Aim: Permanent hypoparathyroidism is a debilitating morbidity following thyroidectomy and parathyroid auto‐transplantation has been shown to be effective in preventing permanent hypoparathyroidism. Controversy exists regarding the benefit of routine versus selective auto‐transplantation. We evaluate the outcome of selective parathyroid auto‐transplantation in our hospital. Methods: A retrospective study was conducted to assess the incidence of postoperative hypocalcaemia. Indication for parathyroid auto‐transplant was doubtful viability of parathyroid gland during thyroidectomy. From 1 July 2000 to 30 June 2005, all patients who underwent total, subtotal and completion thyroidectomy were included. Other outcome measures including recurrent laryngeal nerve injury and operative time were also analyzed. Results: A total of 170 bilateral or completion thyroidectomies were performed within this period. Total, subtotal, and completion total thyroidectomies were performed in 103 (60.6%), 62 (36.5%), and five (2.9%) patients, respectively. Median age was 45 years (range 19–82). One hundred and twenty‐four patients (73%) had benign thyroid disease, and 46 patients (27%) had thyroid carcinoma. Parathyroid auto‐transplant was performed in 35 patients (20.6%). Mean operation time was 204 min (range 95–510 min). There was no difference in the operation time between the patients with parathyroid auto‐transplant and those without auto‐transplant (217 vs 200 min, P = 0.229). Transient hypocalcaemia occurred in 31 patients (18.2%) whereas two patients had permanent hypocalcaemia (1.2%). Permanent recurrent laryngeal nerve injury occurred in one patient (0.6%). Conclusions: The adoption of selective parathyroid auto‐transplant during thyroidectomy achieves an extremely low incidence of permanent hypoparathyroidism without excessive transient hypoparathyroidism.     

Postmastectomy reconstruction with extended latissimus dorsi myocutaneous flap for Hong Kong Chinese

Objective: Because of the smaller breast size of Chinese women, postmastectomy reconstruction without prosthesis by extended latissimus dorsi (LD) flap is potentially more applicable in the Chinese population. Methods: Patients who had undergone immediate postmastectomy breast reconstruction by extended latissimus dorsi flap without prosthesis were retrospectively studied. Surgical complications, aesthetic result and patient satisfaction were evaluated. Results: Ten Asian patients (nine Chinese and one Filipino) underwent extended LD flap for breast reconstruction after mastectomy. There was no total or partial flap failure. Operative complications included seroma in one patient and minor wound edge slough at back wounds in two patients. Simultaneous seroma and minor donor wound slough occurred in another patient. Aesthetic outcome was excellent (n = 5), good (n = 4) and poor (n = 1). Patient satisfaction with the procedure was very satisfied in four, satisfied in four and dissatisfied in two, respectively. All but two patients would recommend the same procedure to their friends or relatives. Conclusion: Extended LD flap can reliably achieve pleasing results with low morbidity. It has more potential to become a competitive alternative to transverse abdominis myocutaneous flap in most Chinese women for postmastectomy reconstruction.     

Melatonin and prostate cancer cell proliferation: interplay with castration,epidermal growth factor,and androgen sensitivity

BACKGROUND: Potential modulatory effects of melatonin on the proliferation of androgen-sensitive LNCaP and androgen-insensitive PC-3 and DU 145 prostate cancer cells were reported recently. In this study, we investigated the effects of combined melatonin and castration on LNCaP tumor growth in vivo, the interactions between melatonin and epidermal growth factor (EGF) on LNCaP cell proliferation, and melatonin actions on the proliferation of PC-3 and DU 145 cells. METHODS: Tumor development and growth in castrated nude mice inoculated with LNCaP cells or in intact animals inoculated with DU 145 cells, with or without daily melatonin treatment, were monitored by observation and caliper measurement. MT(1) receptor expression in native or transfected prostate cancer cell lines was examined by immunocytochemistry or 2-[(125)I]iodomelatonin binding. Cyclin D1 expression in LNCaP cells was assessed by Western blotting, and cell proliferation was measured by thymidine incorporation and/or cell count. RESULTS: Melatonin treatment was associated with further decreases in LNCaP tumor incidence and growth rate in castrated nude mice. Melatonin and 2-iodomelatonin (a melatonin receptor agonist) attenuated EGF-stimulated increases in LNCaP cell proliferation and cyclin D1 levels. Melatonin had no effect on the proliferation or growth of MT(1) receptor-expressing DU 145 cells, and of PC-3 cells in which MT(1) receptor protein was undetectable. The proliferation of transfected PC-3 cells expressing MT(1) receptor was unaffected by 2-iodomelatonin. CONCLUSION: Together with previous data, the present results indicate synergistic action of melatonin and castration in inhibiting the growth of androgen-sensitive LNCaP tumor. Androgen-sensitive prostate cancer cell proliferation may be modulated by opposite changes in cyclin D1 levels induced by activated MT(1) and EGF receptors. In androgen-insensitive prostate cancer cells, MT(1) receptor-mediated signal transduction may become defective not only through changes in membrane receptor protein expression and/or functions, but also by means of alterations in downstream postreceptor signaling events.     

Konno aortoventriculoplasty in children and adolescents: from prosthetic valves to the Ross operation

BACKGROUND: In children with complex multilevel left ventricular outflow tract obstruction (LVOTO), the Konno aortoventriculoplasty is used to enlarge the aortic root and increase the size of the aortic valve implanted. We present our experience with the evolution of this surgical approach from prosthetic valves to the Ross operation. METHODS: Between March 1982 and July 2000, 60 patients (36 males and 24 females) had 72 Konno aortoventriculoplasties (prosthetic valve and Konno group [57 patients; redo, 12] and Ross-Konno group [15 patients]). The patients' ages ranged from 5 days to 18 years (mean, 8.2 years). The underlying anatomic diagnoses were congenital aortic stenosis and LVOTO in 51 patients, coarctation of the aorta with bicuspid aortic valve in 13, severe aortic insufficiency associated with a ventricular septal defect in 8, interrupted aortic arch in 6, mitral stenosis in 6, atrioventricular septal defect in 5, and endocarditis in 3. There was no statistical difference in age or diagnosis between the two groups. The prosthetic valve group included 42 mechanical valves, 9 homografts, and 6 xenografts. RESULTS: Follow-up ranged from 10 months to 18.5 years (mean, 9.7 years) in the prosthetic valve and Konno group compared with 5 months to 3.7 years (mean, 2.1 years) in the Ross-Konno group (p < 0.05). There were 10 early deaths and four late deaths in the prosthetic valve and Konno group as compared with one early death and two late deaths in the Ross-Konno group (p = not significant). Reoperations for LVOTO and aortic valve replacement were significantly higher in the prosthetic valve and Konno group as opposed to the Ross-Konno group (16 vs 0, p < 0.05) mainly because of the biological valve and Konno subgroup. There were no statistical differences in reexploration for bleeding, pacemaker insertion, and reoperations for indications other than LVOTO and aortic valve replacement between the two groups. CONCLUSIONS: The Konno aortoventriculoplasty is a good surgical option for complex LVOTO. Patients with a prosthetic valve and Konno carry a high rate of reoperation. Early operative results with the Ross-Konno operation seem promising.     

Mechanical Testing of Seven Fixation Methods for Generation of Compression Across a Midtarsal Osteotomy: A Comparison of Internal and External Fixation Devices

The purpose of this study was to assess 7 methods of fixation for a midtarsal osteotomy. Polyurethane foam models (N = 6) and cadaver specimens (N = 4-7) were used to examine the force generated by the different constructs of fixation. A midtarsal osteotomy was performed on each specimen in the test groups. The osteotomies were fixated either with 2 parallel 0.062-in Kirschner wires and 40-mm-long, 4-mm partially threaded, cancellous, cannulated titanium screws, an external ring fixator (frame), a frame with wires tensioned (tension), a frame with wires tensioned and compressed toward the osteotomy (tension and compression), a frame with tension, compression, and parallel Kirschner wires, or a frame with tension, compression, and two 4.0 cannulated parallel screws, respectively. Each model was fixated, and the force generated by the construct across the osteotomy was recorded via the use of pressure-sensitive film. Statistical analysis of the data in the polyurethane foam group determined that the use of frame with tension, compression, and two 4.0 parallel cannulated screws was statistically superior to 1) frame, 2) frame with tension, 3) 2 parallel Kirschner wires, 4) two 4.0 cannulated parallel screws, and 5) frame with tension and compression. A cadaver study determined that the frame with tension, compression, and 2 parallel Kirschner wires was statistically superior to 1) frame and 2) two parallel Kirschner wires. These findings suggest that there is a difference in the force generated by the type of fixation construct across a midtarsal osteotomy.     

Initial experience in children using conventional laparoscopic instruments in single-incision laparoscopic surgery

Background

Single-incision laparoscopic surgery (SILS) has been successfully performed in children using 5-mm reticulating instruments. There are, however, few reports investigating the use of conventional instruments in SILS in the pediatric population.

Methods

We conducted a retrospective review of all consecutive children who underwent SILS from October 2009 to January 2010, with the procedure being solely performed by conventional 3- and 5-mm instruments through a standard access technique.

Results

A total of 19 SILS procedures were successfully performed in children aged 3 to 15 years. They included appendectomy (n = 10), nephrectomy (n = 1), combined cholecystectomy and splenectomy (n = 2), cholecystectomy (n = 1), high ligation for varicocele (n = 2), excision of Meckel diverticulum (n = 1), and staged orchidopexy and exploration for impalpable testis (n = 2). There was one conversion to conventional laparoscopic surgery, and that occurred in our first case of splenectomy. All the patients had smooth recovery from surgery without complications.

Conclusions

Using conventional instruments in SILS is technically feasible in children from simple to complex procedures and may have the potential to popularize this approach by eliminating the mandatory demand for specially designed instruments.     

Systemic fungemia and hepatic localizations of Fusarium solani in a liver transplanted patient: an emerging fungal agent.

The incidence of invasive fungal infection is increasing especially in the field of transplantation, affecting as many as 50% of bone marrow transplant (BMT) patients with neutropenia and 5-20% of solid-organ transplant (SOT) recipients. Fusarium species are soil saprophytes and plant pathogens. They may cause superficial mycoses or important opportunistic infections in patients with bone marrow suppression and neutropenia, they have been rarely described in solid organ recipients, and up to now there have been no reports of such infection in isolated liver transplanted patients. We describe a case of disseminated Fusarium solani infection with hepatic localization in a liver transplanted patient that resolved with the administration of amphotericin B. Our observation confirms that Fusarium spp. are emerging pathogens that may most frequently affect not only BMT patients and patients with hematological malignancies, but also SOT patients. They may cause both localized and disseminated infection. In conclusion, Fusarium spp. etiology should be considered in the context of infectious diseases following liver transplantation.     

Regulatory T cells in transplantation: does extracellular adenosine triphosphate metabolism through CD39 play a crucial role?

Despite tremendous improvements in short-term renal allograft survival, many patients still have chronic rejection or side effects of nonspecific immunosuppression. The discovery of Foxp3⁺ regulatory T cells (Tregs) has revolutionized the concepts in immunoregulation and offers perspectives for overcoming rejection. Recently, a subset of Foxp3⁺CD39⁺ effector/memory-like Tregs (T_REM) was identified. The role of CD39⁺ Tregs in immunoregulation is supported by the occurrence of alopecia areata and experimental autoimmune encephalomyelitis in CD39-deficient mice and by the failure of CD39^? Tregs to suppress contact hypersensitivity. In humans, CD39 polymorphisms have been associated with diabetes and nephropathy, and multiple sclerosis patients have reduced numbers of blood CD39⁺ Tregs. Preliminary experiments in a murine transplantation model showed that CD39⁺ Tregs can determine allograft outcome. CD39 degrades the extracellular adenosine triphosphate (ATP) released during tissue injury, which otherwise would trigger inflammation. Currently, our groups are assessing the role of CD39⁺ Tregs and extracellular ATP metabolism in clinical transplantation and whether tolerogenic Treg profiles possess immunopredictive value, envisioning the development of clinical trials using CD39⁺ Treg-based vaccination for autoimmunity or transplantation. This is a comprehensive review on the fundamentals of Treg biology, the potential role of ATP metabolism in immunoregulation, and the potential use of Treg-based immunotherapy in transplantation.     

Saphenous vein homograft: a superior conduit for the systemic arterial shunt in the Norwood operation

BACKGROUND: Excessive pulmonary blood flow increases ventricular volume work in the face of inadequate systemic cardiac output, low diastolic blood pressure, and inadequate coronary perfusion. Using the smallest available 3-mm polytetrafluoroethylene shunts have been successful, although catastrophic shunt thrombosis has occasionally been observed. To avoid thrombosis with a smaller conduit, saphenous vein homografts (SVG) were used to construct the modified Blalock-Taussig (BT) shunts. METHODS: From January 1998 to April 1999, 25 patients weighing 3.1 kg (3.0 kg or less, n = 9), at a mean age of 8.9 days, underwent stage I Norwood using an SVG BT shunt. Common heart defects were aortic atresia (n = 8), mitral atresia and double-outlet right ventricle (n = 5), and unbalanced AVC (n = 5). Mean BT shunt size was 3.2 mm, with 12 patients having shunts that were 3 mm or smaller. RESULTS: Thirty-day hospital mortality was 8% (2 of 25). No shunt thrombosis was seen, despite banding the BT shunt in 3 patients. One patient had BT revision because of an anatomic issue not directly related to the shunt material. CONCLUSIONS: Excellent results may be achieved using SVG BT shunts in the Norwood operation. This conduit seems less likely to thrombose, both acutely and chronically, allowing the use of appropriately smaller-sized shunts in small neonates.