Mechanisms of repigmentation induced by photobiomodulation therapy in vitiligo

Photobiomodulation (PBM) therapy is based on the exposure of biological tissues to low‐level laser light (coherent light) or light‐emitting diodes (LEDs; noncoherent light), leading to the modulation of cellular functions, such as proliferation and migration, which result in tissue regeneration. PBM therapy has important clinical applications in regenerative medicine. Vitiligo is an acquired depigmentary disorder resulting from disappearance of functional melanocytes in the involved skin. Vitiligo repigmentation depends on available melanocytes derived from (a) melanocyte stem cells located in the bulge area of hair follicles and (b) the epidermis at the lesional borders, which contains a pool of functional melanocytes. Since follicular melanoblasts (MBs) are derived from the melanocyte stem cells residing at the bulge area of hair follicle, the process of vitiligo repigmentation presents a research model for studying the regenerative effect of PBM therapy. Previous reports have shown favourable response for treatment of vitiligo with a low‐energy helium‐neon (He‐Ne) laser. This review focuses on the molecular events that took place during the repigmentation process of vitiligo triggered by He‐Ne laser (632.8 nm, red light). Monochromatic radiation in the visible and infrared A (IRA) range sustains matrix metalloproteinase (MMP), improves mitochondrial function, and increases adenosine triphosphate (ATP) synthesis and O₂ consumption, which lead to cellular regenerative pathways. Cytochrome c oxidase in the mitochondria was reported to be the photoacceptor upon which He‐Ne laser exerts its effects. Mitochondrial retrograde signalling is responsible for the cellular events by red light. This review shows that He‐Ne laser initiated mitochondrial retrograde signalling via a Ca²⁺‐dependent cascade. The impact on cytochrome c oxidase within the mitochondria, an event that results in activation of CREB (cyclic‐AMP response element binding protein)‐related cascade, is responsible for the He‐Ne laser promoting functional development at different stages of MBs and boosting functional melanocytes. He‐Ne laser irradiation induced (a) melanocyte stem cell differentiation; (b) immature outer root sheath MB migration; (c) differentiated outer root sheath MB melanogenesis and migration; and (d) perilesional melanocyte migration and proliferation. These photobiomodulation effects result in perifollocular and marginal repigmentation in vitiligo.     

Computed tomography imaging features for amyloid dacryolith in the nasolacrimal excretory system: A case report

BACKGROUNDNasolacrimal duct obstruction leading to epiphora is a common ophthalmologic complaint, and it may derive from amyloidosis in rare cases. There are a few reports about localized amyloidosis, and amyloidosis with involvement and obstruction of the nasolacrimal duct is exceedingly rare. CASE SUMMARYA 54-year-old male presented with a 2-year history of a lump overlying the left lacrimal sac that had grown rapidly for nearly half a year. Physical examination touched a firm lump in the left lacrimal sac. Nasal endoscopy discovered lesions in appearance of sediments with easy bleeding at the entry of the nasolacrimal duct of the left inferior nasal meatus. Computerized tomography scan revealed speckle high density in the left lacrimal sac and the dilated nasolacrimal duct. During an endoscopic exploration and excision, a large number of dacryoliths were exposed. Pathology indicated amorphous pink material and multinucleated giant cell reaction in the fibrous tissue.CONCLUSIONThis case showed amyloidosis in localized form mimicking dacryolith with nasolacrimal duct obstruction. In clinical practice, we should be aware of the possibility of localized amyloidosis in the nasolacrimal excretory system.     

Clinical significance of quantitative studies of cell nucleus in lymphocytes of the cerebrospinal fluid in leukemia]

The nuclear content, area and perimeter of the nucleus of lymphocytes in the C.S.F. were determined quantitatively by means of image analysis technique. 26 cases of central nervous system lymphocytic leukemia (CNLL), and 8 suspected cases were studied, other 56 cases who did not have leukemic and neoplastic diseases and had normal C.S.F. lymphocytes were taken as a control. Our data showed that all the mean nuclear content (MNC), mean nuclear area (MNA), mean nuclear perimeter (MNP), and the maximum and minimum nuclear contents of the 2 groups of former patients were obviously higher than those of the contral (P less than 0.01). These results presented suggestion that the image analysis technique can be used for differentiating the leukemic lymphocyte from normal one especially in suspected cases, and thus the diagnosis of CNLL might be improved.     

Immigrants et tuberculose : données épidémiologiques récentes

Immigrants, and especially those recently arrived in host countries, are a high-risk group for tuberculosis. In 2006 in France, nearly half of the new cases of tuberculosis were reported in this group. The incidence rate among people born abroad was about seven times higher than that observed in people born in France (38.9/10⁵ vs 5.2/10⁵). The incidence was also the highest in districts with a high proportion of socioeconomically vulnerable population, such as Paris and greater Paris area. The characteristics of French born and non-French born cases differed. Patients born abroad were less likely to have pulmonary tuberculosis (68.2% vs 78.2; p < 0.001) and were more likely to live in institutions (such as migrant shelters) and to harbor multiresistant tuberculosis strains. A national tuberculosis control program was launched in France in 2007, to decrease the prevalence of tuberculosis in targeted populations.     

后腹腔镜手术切除肾上腺节细胞神经瘤疗效观察

目的 :探讨后腹腔镜微创手术治疗肾上腺节细胞神经瘤的适应证和可行性。方法 :采用后腹腔镜手术治疗肾上腺节细胞神经瘤患者 5例 ,其中左侧肾上腺节细胞神经瘤 2例 ,右侧 3例。结果 :5例后腹腔镜手术全部获得成功 ,4例肾上腺肿瘤为单发 ,1例为多发 (4个肿瘤 ) ;肿瘤最大直径 2 .5～ 8.0 (4 .2± 1.8)cm ;手术时间35～ 10 5 (5 9± 2 7)min ,估计出血量 10～ 30 (19± 7)ml,术后镇痛剂吗啡用量 0～ 2 0 (8± 8)mg ,2例未用镇痛剂 ;排气、恢复进食时间 1～ 3(1.4± 0 .5 )d ;术后住院时间 4～ 7(5 .4± 1.5 )d。无围手术期并发症发生。结论 :后腹腔镜手术切除肾上腺节细胞神经瘤是安全可行的 ,能充分体现腹腔镜手术创伤小、恢复快的优点。肾上腺节细胞神经瘤是腹腔镜手术很好的适应证。