Motion artifact seen on slot-scanning direct digital mammography

OBJECTIVE: Our goal was to determine the appearance of motion artifact when imaging an anthropomorphic breast phantom using a digital slot-scanning system compared with a screen-film system. MATERIALS AND METHODS: Digital and screen-film images were obtained during both brief and continuous manually induced motion of an anthropomorphic phantom in four directions. Continuous motion was further characterized using a syringe pump to induce motion artifact. RESULTS: On screen-film images, brief motion caused degradation of the entire image, simulating a double exposure. Conversely, on digital images using a slot-scanning system, brief motion caused degradation of only a small portion of the image. Continuous motion resulted in smearing of phantom details with both systems, although the smearing was more strongly influenced by the direction of motion when the slot-scanning system was used. With the slot-scanning system, motion in the direction of the detector sweep resulted in elongated distortion, whereas motion in the opposite direction resulted in foreshortening; diagonal smearing was seen with perpendicular phantom motion. The magnitude of distortion for continuous motion at a set velocity was substantially less with the slot-scanning system. CONCLUSION: Motion artifact with a slot-scanning direct digital mammography unit differs significantly from that seen with a conventional screen-film unit and, despite a relatively long overall exposure, may prove to be less of a problem than with conventional units because any given part of an object is exposed only briefly.     

Medical therapy and new approaches to management of urolithiasis

A simple, step-by-step approach to diagnosis and medical treatment of stone disease is described. It uses urinary stone risk profile obtained before and after dietary modification, history, and minimum diagnostic tests. For each abnormal stone risk factor, potential causes are discussed and treatment options are presented. The article concludes with diagnosis and treatment of combined disturbances.     

Immune responses against SARS-coronavirus nucleocapsid protein induced by DNA vaccine

The nucleocapsid （N） protein of SARS-coronavirus （SARS-CoV） is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DHSalpha and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobutins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity （DTH） and CD^8＋ CTL responses to N protein.     

Antiopisthorchotic Action of <Emphasis Type="Italic">Saussurea salsa</Emphasis> Extract

The antiparasitic properties of the Saussurea salsa (Pall.) Spreng. extract and its cynaropicrin fraction have been studied on a model of opisthorchosis in golden hamsters. The tested substances produced a dose-dependent therapeutic effect comparable with that of the reference antihelminthic drug biltricide (praziquantel). __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 8, pp. 30 – 32, August, 2005.     

Polycystic ovary syndrome in asian women

There is substantial heterogeneity of symptoms and signs among women with polycystic ovary syndrome (PCOS). In addition to different diagnostic criteria used, the ethnic background of women with PCOS may affect the clinical, hormonal, and metabolic characteristics of this condition. We present here studies related to the clinical, hormonal, and metabolic characteristics and response to the treatment of PCOS in Asia, which may be different from those in Western countries. It is important to take into consideration the ethnic background of patients in future studies related to PCOS.     

Pap smear screening history of women with squamous cell carcinoma and adenocarcinoma of the cervix

BACKGROUND: Since the introduction of the Pap smear screening, the incidence of squamous cell carcinoma (SCC) has decreased significantly, but the incidence of adenocarcinoma (AC) relative to SCC has increased. AIM: To compare the Pap smear history of patients with AC and SCC of the cervix. METHODS: Patients for the study were identified from the database of Queensland Centre for Gynaecological Cancer. Patients with AC and SCC were matched for age at diagnosis and International Federation of Gynecology and Obstetrics stage. The final population included 188 matched pairs, being 376 patients in total. Data were collected upon the histological type of cancer, result of the most recent Pap smear, date and result of the Pap smear prior to the most recent Pap smear and symptoms. Chi-squared tests and Fisher's exact test were used to compare the two patient groups for several variables. RESULTS: Patients with AC had significantly more false-negative results on their most recent Pap smear (P<0.0001) than patients with SCC. The incidence of symptoms such as bleeding and/or vaginal discharge was comparable in patients with AC and SCC. The time between the most recent Pap smear and the diagnosis of cervical cancer was significantly shorter for patients with AC (P=0.01). CONCLUSIONS: Patients with AC had Pap smears more regularly than those with SCC, and their most recent Pap smear was significantly more likely to be normal. Thus, Pap smear prior to a diagnosis of AC is more likely than SCC false-negative and therefore not indicative of cervical cancer.     

Modification by food of the calcium absorbability and physicochemical effects of calcium citrate.

The food-calcium (Ca) interaction was examined in 12 healthy women (mean age 38 years) maintained on a constant metabolic diet. They underwent three phases of study, comprised of control (no Ca), Ca citrate (1 g Ca/day) during meals, and Ca citrate separately from meals. Each phase was 7 days in length and two 24-hour urine samples were collected on days 6 and 7. The rise from the control phase in urinary Ca was slightly more prominent when Ca citrate was given with meals than without (68 and 62%, respectively). The fall in urinary phosphorus was equivalent at about 25% between Ca citrate phases. The rise in urinary citrate and pH and the decline in urinary ammonium were more prominent when Ca citrate was given with meals; however, the changes were small or nonsignificant. The urinary saturation of Ca oxalate, brushite or monosodium urate did not differ between the two Ca citrate phases. There was a nonsignificant rise in serum iron during Ca citrate phases. The results suggest that: 1) dissolution and absorption of Ca citrate might be slightly greater when given with food than without; 2) that the ability of Ca citrate to attenuate crystallization of stone-forming Ca salts in urine is not modified by food; and 3) that Ca citrate may not impair iron absorption from food.     

Microtubule reassembly in surface-activated platelets

It is generally accepted that a circumferential microtubule supports the discoid shape of resting platelets. The fate of the many-coiled polymer following platelet activation, however, has been a subject of considerable debate. Morphological investigations have suggested that the circumferential coils are constricted into tight rings around centrally concentrated organelles during platelet shape change. Biochemical studies employing colchicine-binding assays, on the other hand, have indicated that the bundle of microtubules dissolves almost completely within seconds after activation and reassembles in a new location one to four minutes later. The present study has accepted the latter hypothesis in order to examine the second part of the disassembly-reassembly theory proposed in biochemical studies. Platelets exposed to low temperatures sufficient to remove all microtubules were placed on glass slides and microscope grids to cause surface activation during rewarming. The combined stimuli of rewarming and surface activation might have been expected to cause more rapid assembly than warming alone or activation alone. This was not the case. Reassembly of microtubules during rewarming and simultaneous surface activation was not accelerated. In contrast to the constriction of microtubule rings observed during activation in control platelets, the diameters of coils that developed in chilled platelets one to two hours after rewarming and surface activation were twice those of control cells.