Claudin-10 Decrease in the Submandibular Gland Contributes to Xerostomia.

Tight junction proteins play a crucial role in paracellular transport in salivary gland epithelia. It is clear that severe xerostomia in patients with HELIX syndrome is caused by mutations in the claudin-10 gene. However, little is known about the expression pattern and role of claudin-10 in saliva secretion in physical and disease conditions. In the present study, we found that only claudin-10b transcript was expressed in human and mouse submandibular gland (SMG) tissues, and claudin-10 protein was dominantly distributed at the apicolateral membranes of acini in human, rat, and mouse SMGs. Overexpression of claudin-10 significantly reduced transepithelial electrical resistance and increased paracellular transport of dextran and Na+ in SMG-C6 cells. In C57BL/6 mice, pilocarpine stimulation promoted secretion and cation concentration in saliva in a dose-dependent increase. Assembly of claudin-10 to the most apicolateral portions in acini of SMGs was observed in the lower pilocarpine (1 mg/kg)-treated group, and this phenomenon was much obvious in the higher pilocarpine (10 mg/kg)-treated group. Furthermore, 7-, 14-, and 21-wk-old nonobese diabetic (NOD) and BALB/c mice were used to mimic the progression of hyposalivation in Sjögren syndrome. Intensity of claudin-10 protein was obviously lower in SMGs of 14- and 21-wk-old NOD mice compared with that of age-matched BALB/c mice. In the cultured mouse SMG tissues, interferon-γ (IFN-γ) downregulated claudin-10 expression. In claudin-10-overexpressed SMG-C6 cells, paracellular permeability was decreased. Furthermore, IFN-γ stimulation increased p-STAT1 level, whereas pretreatment with JAK/STAT1 antagonist significantly alleviated the IFN-γ-induced claudin-10 downregulation. These results indicate that claudin-10 functions as a pore-forming component in acinar epithelia of SMGs, assembly of claudin-10 is required for saliva secretion, and downregulation of claudin-10 induces hyposecretion. These findings may provide new clues to novel therapeutic targets on hyposalivation.

Utility of navigation system-guided submandibular gland core needle biopsy in the diagnosis of immunoglobulin G4-related sialadenitis.

Pathological diagnosis is important for the definite diagnosis of immunoglobulin G4-related sialadenitis (IgG4-RS). Core needle biopsy (CNB) is a scarless technique; however the pathological heterogeneity of IgG4-RS (a particular feature of this disease) could be the potential cause of the inferior diagnostic capability of submandibular gland CNB (SMG-CNB) for IgG4-RS. The aim of this study was to explore technical improvements in SMG-CNB and improve its diagnostic power in IgG4-RS diagnosis. Eighteen patients clinically suspected for IgG4-RS were enrolled and underwent both SMG-CNB and SMG surgical biopsy. A navigation system (Brainlab) was employed during SMG-CNB to obtain representative samples and avoid blood vessel injury. Histopathological and immunopathological findings for the SMG-CNB samples were in good concordance with SMG surgical biopsy. There was no statistically significant difference between SMG-CNB and SMG surgical biopsy in IgG-positive cell count (132.4 ± 59.3 vs 132.2 ± 47.5, P = 0.99), IgG4-positive cell count (102.2 ± 39.7 vs 97.2 ± 27.6, P = 0.67), or IgG4-positive/IgG-positive cell count ratio (78.6% ± 0.1% vs 75.2% ± 0.1%, P = 0.29). A moderate or strong significant correlation was found between SMG-CNB and SMG surgical biopsy for these cell counts and ratio (all P < 0.01). The diagnostic consistency of SMG-CNB and SMG surgical biopsy was 100%. The Brainlab navigation system may assist in collecting representative SMG-CNB samples from typical pathological lesions. Tissues obtained from SMG-CNB are sufficient for the pathological diagnosis of IgG4-RS. Standardized SMG-CNB is expected to replace SMG surgical biopsy for IgG4-RS diagnosis.

[Establishment and application of new techniques for submandibular gland preservation].

The saliva secreted from submandibular gland (SMG) accounts for 60%-65%. It plays an important role in maintaining the human function of swallow, digestion, testing, speech, protection of oral mucosa, and prevention from dental carries. The SMG is frequently resected during the treatment for various kinds of oral and maxillofacial diseases, resulting in xerostomia and decreased quality of life. During the past 15 years, Research Center of Salivary Gland Diseases in Peking University School and Hospital of Stomatology conducted a series of studies on new techniques for preservation of SMG and achieved remarkable results. The clinicopathologic and imaging characteristics of IgG4-related sialadenitis (IgG4-RS) were clarified based on systematic studies. The results of studies on the pathogenesis of IgG4-RS showed that unbalance of inflammatory factors mediated the abnormality of secretion of SMG. IL-4 participates in occurring and development of glandular fibrosis of SMG. Regulation of tumor necrosis factor α (TNF-α) and cleaning of senescent cells might be taken as the targets for treatment of IgG4-RS. The combination of glucocorticoid and steroid-sparing agents showed effective results for treating IgG4-RS, clinical remission was achieved in all the patients, serum IgG4 levels decreased, and salivary gland secretion significantly increased. Sialoendoscopy-assisted sialolithectomy was applied in the treatment of about 1 000 cases with submandibular hilar calculi with a success rate of more than 90%. Transfer of SMG was used for prevention from radiation-induced xerostomia in the patients with head and neck carcinoma. SMG was transferred to the submental region before radiotherapy and was kept away from the ra-diation field. The results of prospective clinical controlled study showed this technique could effectively preserve the function of SMG and prevent from xerostomia. Based on the micro-anatomical study on the blood vessels and ducts of SMG, partial sialoadenectomy was applied for treatment of benign tumors in the SMG. A clinical controlled study confirmed its safety for control of the tumors and its advantage of preservation of SMG function. The studies on the involvement of SMG in oral squamous cell carcinoma (OSCC) provided the anatomical and histopathological basis for preservation of SMG during neck dissection for early cases with OSCC. A innovated surgical modality "four preservations including SMG" was used during the neck dissection for the early cases with OSCC. A prospective randomized clinical controlled study confirmed its safety, feasibility, effectiveness for control of the carcinoma, and advantages of preservation of SMG function.

[Studies on newly recognized chronic sialadenitis].

Some kinds of chronic sialadenitis were recognized during the recent years. They have specific pathogenesis, clinical and histopathologic appearances, and require specific treatment. IgG4-related sialadenitis (IgG4-RS) is one of the immune-mediated diseases, characterized by tumefactive lesions. The incidence of IgG4-RS obviously increased during the past 30 years. The study on the potential relationship between occupational exposure to chemical substances and the incidence of IgG4-RS showed that subjects with occupational exposure to agents known to cause IgG4-RD had an increased risk for IgG4-RS. Surgical excision of involved SMG could not control the disease progression, which is not recommended for treatment of IgG4-RS. The combination of glucocorticoid and steroid-sparing agents is effective for treating IgG4-RS, and restores salivary gland function. Radioiodine induced sialadenitis (RAIS) is one of the common complications of postoperative adjuvant treatment of differentiated thyroid cancer by 131I. The incidence of the disease is related to radiation dosage. Clinically, the patients suffered from swelling and tenderness in the buccal or submandibular regions, especially during the mealtime. Imaging appearances are similar to those of chronic obstructive sialadenitis. Conservative managements, such as gland massage, sialagogues, are the mainstream methods in the treatment of RAIS. Sialendoscopy is feasible for RAIS, but not as effective as conventional obstructive sialadenitis (COS). Therefore the prevention of RAIS is crucial. Eosinophilic sialodochitis (ES) is a new type of chronic inflammatory disease of the salivary gland related to allergy. It has characteristics of swelling of multiple major salivary glands, strip-like gelatinous plugs discharged from the duct orifice of the gland, elevated level of serum IgE and eosinophils in peripheral blood, infiltration of eosinophils and IgE positive plasma cells in the tissues, allergic history, increased expression of allergy-related cytokines, such as IL-4, IL-5, IL-13, and eotaxin, which suggest allergic reactions as a potential pathogenesis of the disease. The clinical, laboratory, histological, and immunohistochemical characteristics of ES are significantly different from conventional obstructive sialadenitis (COS). Therefore, it is suitable to separate ES from COS. Conservative managements, such as self-maintenance therapy and anti- allergic modality are the choices of treatment for ES. Based on the results of our comprehensive studies a new classification of chronic sialadenitis is suggested.

[Effects of acid stimulation on saliva flow rate and compositions of human parotid and submandibular glands].

OBJECTIVE: To investigate the effect of acid stimulation on salivary flow rate and compositions of human parotid and submandibular glands, so as to provide basis for comprehensive evaluation of salivary gland function in both health and disease status. METHODS: In the study, 210 healthy participants' whole saliva samples were collected under passive drooling, and their parotid gland and submandibular gland secretions were collected by negative pressure suction. 2% citric acid was dropped on the tip of tongue every 1 min for acid stimulation for a total of 5 times to collect stimulated whole saliva, parotid and submandibular gland saliva. The collected saliva was weighed and saliva flow rate was calculated. The K+, Na+, Cl-, Ca2+, total protein, total phosphorus and α-amylase in saliva samples were detected by biochemical analyzer, and the changing features of flow rate and compositions of different kinds of saliva were compared and analyzed. RESULTS: After acid stimulation, saliva flow rate significantly increased. The increase proportion of parotid gland saliva (10.7 folds) was much higher than that of submandibular gland saliva (2.9 folds). The concentrations of Na+, Cl-, Ca2+, total protein and α-amylase in parotid gland saliva increased significantly (P < 0.05), but there was no significant difference in total phosphorus and K+ (P=0.89, P=0.34). The concentration of Na+ and Ca2+ in saliva of submandibular gland increased significantly(P < 0.05), the concentration of total phosphorus decreased significantly(P < 0.05), and the concentration of Cl- increased, but the difference was not significant(P=0.068). There was no significant difference in total protein, K+ and α-amylase (P=0.85, P=0.07, P=0.95). The compound secretion rate of total phosphorus in saliva of submandibular gland remained unchanged(P=0.066), while the secretion rate of K+, Na+, Cl-, Ca2+, total protein and α-amylase significantly increased(P < 0.01). The compound secretion rate of K+, Na+, Cl-, Ca2+, total protein and total phosphorus and α-amylase in parotid gland saliva increased(P < 0.01). The concentrations of Na+, Cl-, K+, total phosphorus, total protein and α-amylase in parotid were higher than those in submandibular gland (P < 0.01), and the concentration of Ca2+ in submandibular gland saliva was significantly higher than that in parotid (P < 0.001). CONCLUSION: The response of parotid to acid stimulation is stronger, and the secretion of submandibular gland is more stable. Acid stimulation significantly influences the concentrations of electrolytes in saliva, and the composited secretion rate is an evaluation index to reflect both flow rate and composition concentration of saliva. The parotid gland plays an important role in the secretion of total protein, total phosphorus and α-amylase in saliva, and the submandibular gland is the main source of Ca2+ in saliva.

Differences between radioactive iodine-induced sialadenitis and chronic obstructive parotitis.

The purpose of this study was to clarify the differences in the diagnosis and treatment outcomes between radioactive iodine-induced sialadenitis (RAIS) and chronic obstructive parotitis (COP). The study cohort comprised 47 consecutive patients diagnosed with RAIS and 50 patients with COP. All patients were treated by interventional endoscopy. Clinical, sialography, and endoscopy characteristics and treatment outcomes were compared between the two groups. Compared with the COP group, the RAIS group included more females (male:female ratio 1:8.4 vs 1:2.1; P = 0.011) and had a younger onset age (42 vs 50 years; P = 0.001) and shorter disease duration prior to hospital visit (5.4 vs 34.8 months; P < 0.001). In the RAIS group, sialography revealed obliteration of the main duct (20.4% vs 0%; P < 0.001), non-visualization of the main gland (23.7% vs 0%; P < 0.001), and incomplete contrast filling of the main gland (19.4% vs 6.4%; P = 0.008), which were scarcely observed in the COP group. Endoscopy revealed a higher percentage of duct atresia in RAIS compared to COP (20.4% vs 0%; P < 0.001). During follow-up, a higher percentage of RAIS patients had duct atresia and gland atrophy (49.5% vs 1.1%, P < 0.001). Compared with COP, RAIS more commonly involves younger females and has a shorter disease duration. Atresia of the main duct and atrophy of the gland parenchyma occur more often despite the use of interventional endoscopy.

[Inflammation grading and sialoendoscopic treatment of 131I radioiodine-induced sialadenitis].

OBJECTIVE: To investigate the inflammation grading of 131I radioiodine-induced sialadenitis based upon sialoendoscopic and sialographic appearances, and to evaluate the results of sialoendoscopic intervention. METHODS: The patients diagnosed with 131I radioiodine-induced sialadenitis and underwent sialoendoscopic exploration and intervention procedures in Peking University Hospital of Stomatology from Nov. 2012 to Oct. 2018 were included in this study. The appearances of sialogaphy and sialoendoscopy were analyzed and classified. The treatment options included irrigation with saline and dexamethasone and mechanical dilatation by sialoendoscope. The patients were followed up after treatment. RESULTS: Forty-two patients with 131I radioiodine-induced sialadenitis were included. There were 5 males and 37 females, with a male-to-female ratio of 1 ∶7.4. Symptoms included recurrent swelling and pain in the parotid glands, and dry mouth. Sialography showed stenosis in the main duct,and in some cases nonvisua-lization of the branches. Sialoendoscopy showed narrowing of the main duct, and the branch duct atresia was seen. The appearances of sialogaphy and sialoendoscopy were analyzed and classified into 3 groups: (1) Mild inflammation: stenosis and ectasia occurred in the main duct, whereas the 0.9 mm sialoendoscope could pass through easily. (2) Moderate inflammation: one point of severe stricture could be seen in the main duct where 0.9 mm sialoendoscope could not be passed through. (3) Severe inflammation: two points or more of severe strictures or diffused strictures occurred in the main duct. Thirty-three patients with 65 affected glands were examined by both sialography and sialoendoscopy. Eight glands were classified as mild inflammation, 23 glands moderate inflammation, and 34 glands severe inflammation. The duration of follow-up ranged from 3-72 months. The clinical results were evaluated as good in 22 glands, fair in 22 glands, and poor in 19 glands, with an overall effective rate of 69.8% (44/63). CONCLUSION: The clinical, sialographic and sialoendoscopic appearances of 131I radioiodine-induced sialadenitis showed their characteristics. We proposed an inflammation grading standard for the 131I radioiodine-induced sialadenitis based on the appearances of sialography and sialoendoscopy. Sialoendoscopy can significantly alleviate the clinical symptoms, which is an effective therapy, and better for early lesions.

Clinicopathological study of involvement of the submandibular gland in oral squamous cell carcinoma.

Our purpose was to provide a pathological basis for preservation of the submandibular glands during neck dissection for oral squamous cell carcinoma (SCC) by investigating whether intraglandular lymph nodes exist in submandibular glands, and the modes of involvement of submandibular glands in oral SCC. We studied the records of 95 patients with oral SCC (other than that in the floor of the mouth) treated at our hospital from January 2017 to June 2018. The specimens of submandibular glands discarded after neck dissection were analysed, and serially sectioned. Sections 5µm thick were obtained at 0.5mm intervals and stained with haematoxylin and eosin for examination under light microscopy. A total of 116 specimens were obtained from the 95 patients, and about 5000 slides were evaluated. No intraglandular lymph nodes were detected in the submandibular glands. In the subgroup of patients whose primary tumours had extended into the floor of the mouth, four submandibular glands were involved by direct spread of the primary tumour. In the subgroup with metastases to level Ib lymph nodes, four submandibular glands were involved by extranodal extension from the metastatic nodes. No intraglandular lymph nodes or micrometastases were detected. We conclude that no intraglandular lymph nodes are present in submandibular glands, which may be involved by direct extension of the primary carcinoma or metastatic cervical lymph nodes with extranodal extension. Preservation of the submandibular glands during neck dissection seems to be feasible and safe in selected patients with oral SCC.

Involvement of the submandibular gland in oral squamous cell carcinoma patients with positive lymph nodes.

BACKGROUND: No consensus exists about submandibular glands (SMGs) involvement in oral squamous cell carcinoma (OSCC) patients with cervical lymph node metastasis. We aimed to investigate the prevalence of SMG involvement in OSCC patients with positive lymph nodes. METHODS: Retrospective analysis of data of 302 study subjects with positive lymph nodes in OSCC operated between January 2002 and December 2012. RESULTS: Only 1/302 (0.3%) study subject had SMG involvement. The mode of spread was by direct extension of the primary carcinoma. Extracapsular spread of level IB lymph nodes was seen in 12/302 (4%) patients. Only one of these patients had involvement of the fibrous tissue around the SMG. CONCLUSION: SMG involvement is very rare in OSCC patients with cervical lymph node metastasis. Preservation of the ipsilateral SMG during neck dissection might be oncologically safe when involvement by direct spread is unlikely.

[Clinicopathological characteristics and diagnosis of IgG4related sialadenitis].

Immunoglobulin G4-related sialadenitis (IgG4-RS) is a newly recognized immune-mediated disease and one of immunoglobulin G4-related diseases (IgG4-RD). Our multidisciplinary research group investigated the clinicopathological characteristics and diagnosis of IgG4-RS during the past 10 years. Clinically, it showed multiple bilateral enlargement of major salivary glands (including sublingual and accessory parotid glands) and lacrimal glands. The comorbid diseases of head and neck region including rhinosinusitis, allergic rhinitis, and lymphadenopathy were commonly seen, which could occur more early than enlargement of major salivary glands. Internal organ involvements, such as autoimmune pancreatitis, sclerosing cholangitis, and interstitial pneumonia could also be seen. Thirty-five (38.5%) patients had the symptom of xerostomia. Saliva flow at rest was lower than normal. Secretory function was reduced more severely in the submandibular glands than in the parotid glands. Serum levels of IgG4 were elevated in almost all the cases and the majority of the patients had increased IgE levels. CT, ultrasonography, and sialography showed their imaging characteristics. Histologically it showed marked lymphoplasmacytic inflammation, large irregular lymphoid follicles with expanded germinal centers, prominent cellular interlobular fibrosis, eosinophil infiltration, and obliterative phlebitis. Their immunohistological examination showed marked IgG-positive and IgG4-positive plasma cell infiltration and high IgG4/IgG ratio. The disease could be divided into three stages according to severity of glandular fibrosis. The serum IgG4 level was higher and the saliva secretion lower as glandular fibrosis increased. IgG4-RS should be differentiated from other diseases with enlargement of major salivary gland and lacrimal gland, such as primary Sjögren syndrome, chronic obstructive submandibular sialadenitis, and eosinophilic hyperplastic lymphogranuloma.

Factors influencing the long-term results of autologous microvascular submandibular gland transplantation for severe dry eye disease.

We assessed long-term outcomes of autologous microvascular submandibular gland (SMG) transplantation for severe dry eye disease and investigated factors influencing long-term results. From August 1999 to January 2015, 185 patients (200 eyes) with severe dry eye received SMG transplantation. Subjective assessments and ophthalmologic evaluations were performed before and after transplantation. Follow-up results showed successful transplantation in 180 of 200 eyes (success rate: 90%), resulting in marked symptomatic relief of xerophthalmia. Surgery failed due to vascular thrombosis (15 glands) and duct obstruction (5 glands). Follow-up data were available for 163 eyes. Epiphora occurred in 98 (60.1%) eyes and was effectively managed by surgical reduction of graft, topical atropine gel and botulinum toxin injection. Wharton's duct obstruction occurred in 16 (10.6%) eyes and was treated by duct reconstruction. Subjective satisfaction was achieved in 143 (87.7%) eyes. Mean score of fluorescent staining reduced from 11.25±1.42 to 7.25±3.37. Postoperative best-corrected visual acuity improved in 85 (56.3%) eyes. Our clinical experience proved that SMG transplantation is effective and grants long-term improvement in severe dry eye. Secretory function of transplanted SMGs remains active and stable. Blood vessel thrombosis, Wharton's duct obstruction, and epiphora are primary factors influencing results.

[Sorting role of p16(INK4a)/Ki-67 double immunostaining in the cervical cytology specimens of ASCUS and LSIL cases].

Objective: To investigate the sorting effect of p16(INK4a)/Ki-67 double immunostaining method in patients with atypical squamous cells of undetermined significance (ASCUS) or low-grade squamous intraepithelial lesion (LSIL) cytology results. Methods: Four-hundred and twenty cases collected during April 2014 to February 2015 of cervical cytology of ASCUS (n=318) and LSIL (n=102) were selected, and residual liquid-based cytology specimens were used for p16(INK4a)/Ki-67 double immunostaining. The sensitivity and specificity of the detection of cervical precancerous lesions and cervical cancer were calculated, and the results were compared with high risk HPV. Taking histological follow-up as the gold standard, the test was considered positive when at least one cell exhibited p16(INK4a)/Ki-67 co-staining, without requirement of adjunct morphologic interpretation of positive cells. Results: Further screening CIN2+ in cytology ASCUS and LSIL group , the sensitivity of p16(INK4a)/Ki-67 double immunostaining was slightly lower than high risk HPV (84.2% vs. 94.7%), while the specificity was higher (84.0% vs. 53.9%). For ASCUS patients, the sensitivity of p16(INK4a)/Ki-67 double immunostaining and high risk HPV was 82.6% and 91.3%, and the specificity was 88.8% and 63.7%, respectively. For LSIL patients, the sensitivity of p16(INK4a)/Ki-67 double immunostaining and high risk HPV was 86.7% and 100.0%, and the specificity was 67.8% and 20.7%, respectively. For patients younger and older than 30 years, specificity of p16(INK4a)/Ki-67 double immunostaining was both higher than that of high risk HPV (80.8% vs. 42.3%; 84.6% vs. 56.9%). Conclusions: p16(INK4a)/Ki-67 double immunostaining can effectively identify the high risk population in ASCUS or LSIL, with higher specificity than high risk HPV test. p16(INK4a)/Ki-67 double immunostaining may benefit patients younger than 30 years of age as a preliminary or potential cytology-combining screening tool.

Differential diagnosis of IgG4-related sialadenitis, primary Sjögren syndrome, and chronic obstructive submandibular sialadenitis.

Our aim was to differentiate IgG4-related sialadenitis, primary Sjögren syndrome, and chronic obstructive submandibular sialadenitis by analysing clinical, radiographic, and pathological features. Fifty-five patients, 50, and 50 were enrolled, respectively and their baseline characteristics and serological, sialographic, and pathological findings compared. The male:female ratio for IgG4-related sialadenitis was 1:1.2 for primary Sjögren syndrome 1:15.7, and for chronic obstructive submandibular sialadenitis1:0.92. Numbers with enlarged salivary glands were 55, 16, and 50; with xerostomia 26, 48, and 0; with a history of allergy 26, 4, and 6, and with coexisting systemic disease 12, 19, and 0 (p=0.14). Mean (SD) serum IgG4 concentrations were 109.1 (97.9), 4.9. (1.9) g/L, and 5.3 (1.6) g/L, p<0.001 in all cases. Sialography showed enlargement of the gland, dilatation of the duct, and slightly decreased secretory function in IgG4-related disease; obvious sialectasia and decreased secretory function in Sjögren syndrome; and dilatation of Wharton's duct and filling defects in obstructive sialadenitis. Histopathological examination showed lymphoplasmacytic infiltration with storiform fibrosis, lymphoplasmacytic inflammation and lymphoepithelial lesions, and dilatation of the duct with epithelial metaplasia in the three groups, respectively. The number of IgG4-positive plasma cells was 123 (45)/HPF, 8 (3)/HPF, and 5 (4)/HPF, while the IgG4-/IgG-positive cell ratio was 71.7 (13.9)%, 4.6 (2.5)%, 18.9 (19.7)%, respectively (p<0.001). The three conditions have different clinical, radiographic, and pathological features that provide important clues to the differential diagnosis. Serological and histological tests are important, and comprehensive consideration is necessary.

Carbachol improves the secretion of transplanted submandibular glands during the latent period after microvascular autologous transplantation for severe keratoconjunctivitis sicca.

Poor secretion of transplanted submandibular glands (SMGs) during the latent period may cause duct obstruction and affects the surgical outcome. The objective of this study was to investigate the efficacy and systemic side effects of carbachol on transplanted SMG secretion. Twenty-seven patients who underwent SMG transplantation for severe keratoconjunctivitis sicca were treated with subcutaneous injections of 0.2mg/2ml carbachol at 10 days, 1 month, and/or 3 months after surgery. The effect on secretion was evaluated by Schirmer test and technetium 99m ((99m)Tc) scintigraphy. Systemic side effects were evaluated subjectively using a questionnaire. The results showed that the time to onset varied from 4 to 9min and the duration of action from 50 to 110min after carbachol administration. The secretion at each time point after drug administration was significantly higher than the pre-administration value (all P<0.01). (99m)Tc scintigraphy showed a decline in the dynamic time-activity curve in 26 patients, demonstrating a stimulatory effect on the secretion of carbachol. No serious systemic side effects were experienced. In conclusion, the intermittent administration of carbachol could be an effective and safe strategy to promote secretion from transplanted SMGs in the latent period to prevent duct obstruction.

The timing of acid-induced increase in saliva secretion in transplanted submandibular glands.

The purpose of this study was to determine the timing of acid-induced increase in saliva secretion and to investigate the possibility of parasympathetic reinnervation of transplanted submandibular glands (SMGs). Citric acid stimulation-induced changes in secretion of transplanted SMGs were evaluated in 27 patients who underwent SMG transplantation for keratoconjunctivitis sicca (KCS); (99m)Tc scintigraphy and Schirmer tests were done at 1, 3, 6, and 9 months after transplantation. Acetylcholinesterase staining was conducted to confirm the presence of parasympathetic reinnervation in three SMGs at 6 and 9 months after transplantation. Schirmer tests showed significantly increased secretion of the transplanted SMGs after acid stimulation at 6 and 9 months, but not at 1 and 3 months. On (99m)Tc scintigraphy, no decline was detected on the dynamic time-activity curve after acid stimulation at 1 and 3 months, but a decline was detected in nine glands at 6 months and in 19 glands at 9 months. No decline was observed in the remaining eight glands at 9 months after transplantation. The histology findings were consistent with scintigraphy results. In conclusion, acid-induced increase in saliva secretion occurs at ≥6 months after SMG transplantation, and parasympathetic reinnervation of the transplanted SMG might occur.

Effects of the L- and N-type calcium channel blocker cilnidipine on growth of vascular smooth muscle cells from spontaneously hypertensive rats.

Cultured vascular smooth muscle cells (VSMC) from spontaneously hypertensive rats (SHR) show exaggerated growth compared with cells from Wistar-Kyoto (WKY) rats. Calcium antagonists have recently been reported to have an in vivo antiproliferative effect on hypertensive cardiovascular organs. We investigated the effects of the calcium antagonist cilnidipine that blocks both L- and N-type calcium channels on the growth of VSMC from SHR. Cilnidipine (1 and 10 microM) significantly inhibited basal DNA synthesis in VSMC from both rat strains; the inhibition was significantly larger in VSMC from SHR than in cells from WKY rats, and was significantly greater than effects of nifedipine. Cilnidipine (1 microM) significantly inhibited serum-stimulated DNA synthesis in VSMC from both rat strains. The inhibition was more marked in VSMC from SHR than in cells from WKY rats. Angiotensin II, platelet-derived growth factor (PDGF)-AA, and phorbol-12-myristate-13-acetate dose-dependently increased DNA synthesis in VSMC from SHR but not in cells from WKY rats. Cilnidipine (1 microM) significantly suppressed this increase in DNA synthesis in VSMC from SHR. Expression of basic fibroblast growth factor (bFGF), transforming growth factor-beta1, and PDGF A-chain mRNAs was markedly greater in VSMC from SHR than in cells from WKY rats. Cilnidipine (1 microM) significantly inhibited the expression of TGF-beta1 mRNA in VSMC from SHR but not in cells from WKY rats. These findings suggest that cilnidipine exerts its antiproliferative effects through the inhibition of DNA synthesis induced by growth-promoting factors and by inhibiting the expression of TGF-beta1 mRNA in VSMC from SHR.

Quantum-dot-tagged microbeads for multiplexed optical coding of biomolecules.

Multicolor optical coding for biological assays has been achieved by embedding different-sized quantum dots (zinc sulfide-capped cadmium selenide nanocrystals) into polymeric microbeads at precisely controlled ratios. Their novel optical properties (e.g., size-tunable emission and simultaneous excitation) render these highly luminescent quantum dots (QDs) ideal fluorophores for wavelength-and-intensity multiplexing. The use of 10 intensity levels and 6 colors could theoretically code one million nucleic acid or protein sequences. Imaging and spectroscopic measurements indicate that the QD-tagged beads are highly uniform and reproducible, yielding bead identification accuracies as high as 99.99% under favorable conditions. DNA hybridization studies demonstrate that the coding and target signals can be simultaneously read at the single-bead level. This spectral coding technology is expected to open new opportunities in gene expression studies, high-throughput screening, and medical diagnostics.